Robert B Fleischman

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Chapters

• Fleischman, R. B. (2014).

  Seismic Design Methodology Document for Precast Concrete Diaphragms

  . In Seismic Design Methodology for Precast Concrete Floor Diaphragms. PCI/CPF. doi:10.15554/pci.rr.seis-023
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  The design procedure in PART 1 is part of a new seismic design methodology for precast concrete diaphragms. The design methodology and procedure are the product of a large multi-university research project initiated and guided by the Precast/Prestressed Concrete Institute (PCI) and co-funded by PCI, the National Science Foundation (NSF) and the Charles Pankow Foundation (CPF), termed the Diaphragm Seismic Design Methodology (DSDM) project.
• Fleischman, R. B. (2008). Development of a seismic design methodology for precast concrete floor diaphragms. In Tailor Made Concrete Structures New Solutions for our Society, 1st Edition(pp 133-139). CRC Press/Balkema.
• Park, R., Watanabe, F., Alcocer, S. M., Boen, T., Bonelli, P., Bull, D. K., Bull, D. K., Calvi, G. M., Cheok, G. S., Clark, W., Cleland, N., Davidson, B., Englekirk, R. E., Fischinger, M., Fleischman, R. B., French, C. E., Hawkins, N. M., Lngham, J., Macrae, G. A., , Maffei, J., et al. (2003). fib Bulletin 27. Seismic design of precast concrete building structures. In Seismic design of precast concrete building structures. fib. The International Federation for Structural Concrete. doi:10.35789/FIB.BULL.0027
• Fleischman, R. B., Lu, L., Viscomi, B. V., & Goodwin, K. (1995).

  Design and Implementation of ATLSS Connections

  . In National Science Foundation National Conference on Research into Practice(pp 18 pages). Washington DC: National Science Foundation. doi:10.1061/9780784400944.ch10

Journals/Publications

• Poursharifi, M., Abedi, K., Chenaghlou, M., & Fleischman, R. B. (2017). Stability Analysis of Double Layer Barrel Vaults Equipped with an Accordion Force-Limiting Device. Journal of Constructional Research.
• Scheidegger, C., Fleischman, R. B., Kuzucu, I. B., Levine, J. A., Zhao, Z., Motta, D., Berger, M., & Paiva, A. (2021). STFT-LDA: An algorithm to facilitate the visual analysis of building seismic responses. Information Visualization, 20(4), 263-282. doi:10.1177/14738716211038618
• Zhang, D., Lee, D. H., & Fleischman, R. B. (2021). Verification of diaphragm seismic design factors for precast concrete office buildings. Earthquakes and Structures, 20(1), 13-27. doi:10.12989/eas.2021.20.1.13
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  A new seismic design methodology has been developed for precast concrete diaphragms. Seismic design factors were used to be applied on top of diaphragm seismic design forces in the current code. These factors, established through extensive parametric studies, align diaphragm design strengths with different seismic performance targets. A simplified evaluation structure with a single-bay plan was used in the parametric studies. This simplified evaluation structure is reasonable and cost-effective as it can comprehensively cover structural geometries and design parameters. However, further verification and investigation are required to apply these design factors to prototype structures with realistic layouts. This paper presents diaphragm design of several precast concrete office buildings using the new design methodology. The applicability of the design factor to the office building was evaluated and verified through nonlinear time history analyses. The seismic behavior and performance of the diaphragm were investigated for the precast concrete office buildings. It was found that the design factor established for the new design methodology is applicable to the realistic precast concrete office buildings.
• Zhao, Z., Motta, D., Berger, M., Levine, J. A., Kuzucu, I. B., Fleischman, R. B., Paiva, A., & Scheidegger, C. (2021).

  STFT-LDA: An Algorithm to Facilitate the Visual Analysis of Building Seismic Responses

  . Information Visualization, 20(no. 4), 263-282. doi:10.48550/arxiv.2109.00197
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  Civil engineers use numerical simulations of a building's responses to seismic forces to understand the nature of building failures, the limitations of building codes, and how to determine the latter to prevent the former. Such simulations generate large ensembles of multivariate, multiattribute time series. Comprehensive understanding of this data requires techniques that support the multivariate nature of the time series and can compare behaviors that are both periodic and non-periodic across multiple time scales and multiple time series themselves. In this paper, we present a novel technique to extract such patterns from time series generated from simulations of seismic responses. The core of our approach is the use of topic modeling, where topics correspond to interpretable and discriminative features of the earthquakes. We transform the raw time series data into a time series of topics, and use this visual summary to compare temporal patterns in earthquakes, query earthquakes via the topics across arbitrary time scales, and enable details on demand by linking the topic visualization with the original earthquake data. We show, through a surrogate task and an expert study, that this technique allows analysts to more easily identify recurring patterns in such time series. By integrating this technique in a prototype system, we show how it enables novel forms of visual interaction.
• Poursharifi, M., Fleischman, R. B., Chenaghlou, M. R., & Abedi, K. (2020). Introducing a new all steel accordion force limiting device for space structures. Structural Engineering and Mechanics, 74(1), 69-82. doi:10.12989/sem.2020.74.1.069
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  A significant defect of space structures is the progressive collapse issue which may restrict their applicability. Force limiting devices (FLDs) have been designed to overcome this deficiency, though they do not operate efficiently in controlling the force displacement characteristics. To overcome this flaw, a new type of FLD is introduced in the present study. The "all steel accordion force limiting device" (AFLD) which consists of three main parts including cylindrical accordion solid core, tubular encasing and joint system is constructed and its behavior has been studied experimentally. To improve AFLD's behavior, Finite element analysis has been carried out by developing models in ABAQUS software. A comprehensive parametric study is done by considering the effective design parameters such as core material, accordion wave length and accordion inner diameter. From the results, it is found that AFLD can obtain a perfect control on the force-displacement characteristics as well as attaining the elastic-perfect plastic behavior. Obtaining higher levels of ultimate load carrying capacity, dissipated energy and ductility ratio can be encountered as the main privileges of this device. Ease of construction and erection are found to be further advantages of AFLD. Based on the obtained results, a procedure for predicting AFLD's behavior is offered.
• Zhang, D., Lee, D. H., & Fleischman, R. B. (2020). Effects of diaphragm flexibility on the seismic design acceleration of precast concrete diaphragms. Computers and Concrete, 25(3), 273-282. doi:10.12989/cac.2020.25.3.273
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  A new seismic design methodology for precast concrete diaphragms has been developed and incorporated into the current American seismic design code. This design methodology recognizes that diaphragm inertial forces during earthquakes are highly influenced by higher dynamic vibration modes and incorporates the higher mode effect into the diaphragm seismic design acceleration determination using a first mode reduced method, which applies the response modification coefficient only to the first mode response but keeps the higher mode response unreduced. However the first mode reduced method does not consider effects of diaphragm flexibility, which plays an important role on the diaphragm seismic response especially for the precast concrete diaphragm. Therefore this paper investigated the effect of diaphragm flexibility on the diaphragm seismic design acceleration for precast concrete shear wall structures through parametric studies. Several design parameters were considered including number of stories, diaphragm geometries and stiffness. It was found that the diaphragm flexibility can change the structural dynamic properties and amplify the diaphragm acceleration during earthquakes. Design equations for mode contribution factors considering the diaphragm flexibility were first established through modal analyses to modify the first mode reduced method in the current code. The modified first mode reduced method has then been verified through nonlinear time history analyses.
• Zhang, D., & Fleischman, R. B. (2019). Verification of diaphragm seismic design factors for precast concrete parking structures. Structural Engineering and Mechanics, 71(6), 643-656. doi:10.12989/sem.2019.71.6.643
• Zhang, D., Fleischman, R. B., Schoettler, M. J., Restrepo, J. I., & Mielke, M. (2019). Precast Diaphragm Response in Half-Scale Shake Table Test. ASCE Journal of Structural Engineering, 145(5).
• Kurama, Y. C., Sritharan, S., Fleischman, R. B., Restrepo, J. I., Henry, R. S., Cleland, N. M., Ghosh, S. K., & Bonelli, P. (2018). Seismic-Resistant Precast Concrete Structures: State of the Art. JOURNAL OF STRUCTURAL ENGINEERING, 144(4).
• Shakya, U., Fleischman, R. B., Zhang, Z., Restrepo, J. I., Guerrini, G., Nema, A., Zhang, D., Tsampras, G., & Sause, R. (2018). Shake-table test performance of an inertial force-limiting floor anchorage system. Earthquake Engineering & Structural Dynamics, 47(10), 1987-2011. doi:10.1002/eqe.3047
• Tsampras, G., Sause, R., Fleischman, R. B., & Restrepo, J. I. (2018). Experimental study of deformable connection consisting of friction device and rubber bearings to connect floor system to lateral force resisting system. EARTHQUAKE ENGINEERING & STRUCTURAL DYNAMICS, 47(4), 1032-1053.
• Zhang, Z., Fleischman, R. B., Restrepo, J. I., Guerrini, G., Nema, A., Zhang, D., Shakya, U., Tsampras, G., & Sause, R. (2018). Shake-table test performance of an inertial force-limiting floor anchorage system. EARTHQUAKE ENGINEERING & STRUCTURAL DYNAMICS, 47(10), 1987-2011.
• Fleischman, R. B., Tsampras, G., Sause, R., & Restrepo, J. I. (2017). Experimental study of deformable connection consisting of friction device and rubber bearings to connect floor system to lateral force resisting system. Earthquake Engineering & Structural Dynamics, 47(4), 1032-1053. doi:10.1002/eqe.3004
• Tsampras, G., Sause, R., Fleischman, R. B., & Restrepo, J. I. (2017). Experimental study of deformable connection consisting of buckling-restrained brace and rubber bearings to connect floor system to lateral force resisting system. EARTHQUAKE ENGINEERING & STRUCTURAL DYNAMICS, 46(8), 1287-1305.
• Fleischman, R. B., & Seeber, K. (2016).

  New Construction for Resilient Cities: The Argument for Sustainable Low Damage Precast/Prestressed Concrete Building Structures in the 21st Century

  . Scientia Iranica, Special Issue on Resilient Cities(REF # 30.809.151227,). doi:10.24200/sci.2016.2230
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  Thoughtfully-chosen, properly-designed new construction can significantly improve both the resilience to natural and man-induced disasters and the long-term sustainability of modern urban environments in the 21st century. In particular, precast/prestressed concrete construction has the ability to provide low-damage buildings at similar costs to traditional construction while also providing a more sustainable construction form, in terms of higher energy efficiency and lower embodied energy. In this paper, low-damage sustainable precast concrete seismic systems are described. Prestressing leads to less material required and hence less embodied energy; piece erection leads to cleaner, quieter construction sites; and insulation and architectural finish can be integrated directly into the precast unit, increasing energy efficiency and consolidating construction operations. With respect to resilience, earthquake damage is avoided by taking advantage of the inherent jointed nature of precast concrete construction, thereby promoting opening of gaps between precast units rather than cracking of the concrete itself, and using unbonded post-tensioning concepts to restore the structure to its original position. The potential use of precast concrete in developing countries where no precast industry exists is considered in the context of global sustainability. The performance of precast concrete in recent earthquakes is presented as an example of a resilient construction.
• Fleischman, R. B., & Seeber, K. (2016). The Argument for Sustainable Low Damage Precast/Prestressed Concrete Building Structures in the 21st Century. Scientia Iranica, Special Issue on Resilient Cities(REF # 30.809.151227).
• Fleischman, R. B., Tsampras, G., Sause, R., & Restrepo, J. I. (2016). Experimental study of deformable connection consisting of buckling-restrained brace and rubber bearings to connect floor system to lateral force resisting system. Earthquake Engineering & Structural Dynamics, 46(8), 1287-1305. doi:10.1002/eqe.2856
• Fleischman, R. B., Zhang, Z., Zhang, D., Zhang, Z., Mielke, M., & Fleischman, R. B. (2016). Initial Evaluation Of Diaphragm Seismic Demand In A Half-scale Shake Table Test. WIT Transactions on the Built Environment, 160, 71-81. doi:10.2495/susi160081
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  This paper presents an initial evaluation of the seismic demand for diaphragms during a shake table test of a three-story precast concrete structure. Each level of the test structure contained a different precast concrete floor construction technique: topped double tees on the lower level; topped hollow core on the middle floor; and pretopped double tees on the top floor. The diaphragms were designed and detailed according to a new design methodology developed as part of parallel research. The structure was subjected to a series of 16 strong ground motions with increasing intensity including design-basis and maximum considered earthquakes for which the diaphragms were designed. In the paper, the major diaphragm global and local response is quantified. Conclusions are drawn regarding the observed diaphragm behavior.
• Saunders, J. K., Goldberg, D. E., Haase, J. S., Bock, Y., Offield, D. G., Melgar, D., Restrepo, J., Fleischman, R. B., Nema, A., Geng, J., Walls, C., Mann, D., & Mattioli, G. S. (2016). Seismogeodesy Using GPS and Low-Cost MEMS Accelerometers: Perspectives for Earthquake Early Warning and Rapid Response. BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA, 106(6), 2469-2489.
• Scodeggio, A., Quaranta, G., Monti, G., Marano, G. C., & Fleischman, R. B. (2016). Optimization of force-limiting seismic devices connecting structural subsystems. Computers & Structures, 162, 16-27. doi:10.1016/j.compstruc.2015.09.008
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  A seismic protection strategy that uncouples structural subsystems is considered.The force-limiting floor anchorage system is modeled using elasto-plastic springs.The optimal properties and positions of the connectors are determined numerically.Results for a 12-storey prototype reinforced concrete building are discussed. This paper is focused on the optimum design of an original force-limiting floor anchorage system for the seismic protection of reinforced concrete (RC) dual wall-frame buildings. This protection strategy is based on the interposition of elasto-plastic links between two structural subsystems, namely the lateral force resisting system (LFRS) and the gravity load resisting system (GLRS). The most efficient configuration accounting for the optimal position and mechanical characteristics of the nonlinear devices is obtained numerically by means of a modified constrained differential evolution algorithm. A 12-storey prototype RC dual wall-frame building is considered to demonstrate the effectiveness of the seismic protection strategy.
• Tsampras, G., Sause, R., Zhang, D., Fleischman, R. B., Restrepo, J. I., Mar, D., & Maffei, J. (2016). Development of deformable connection for earthquake-resistant buildings to reduce floor accelerations and force responses. EARTHQUAKE ENGINEERING & STRUCTURAL DYNAMICS, 45(9), 1473-1494.
• Zhang, D., & Fleischman, R. B. (2016). Establishment of performance-based seismic design factors for precast concrete floor diaphragms. EARTHQUAKE ENGINEERING & STRUCTURAL DYNAMICS, 45(5), 675-698.
• Zhang, D., Fleischman, R. B., & Zhang, Z. (2016). Analytical Investigation of Seismic Behavior of Building Structures with an Inertial Force-Limiting Floor Anchorage System. International Journal of Engineering and Technology, 8(4), 234-240. doi:10.7763/IJET.2016.V8.891
• Zhang, D., Fleischman, R., & Shon, C. (2016). Preliminary analytical study on seismic ductility demand of wood diaphragms. ADVANCES IN STRUCTURAL ENGINEERING, 19(1), 104-115.
• Zhang, D., Fleischman, R., Naito, C. J., & Zhang, Z. (2016). Development of diaphragm connector elements for three-dimensional nonlinear dynamic analysis of precast concrete structures. ADVANCES IN STRUCTURAL ENGINEERING, 19(2), 187-202.
• Zhang, Z., Fleischman, R., Zhang, D., & Naito, C. J. (2016). Development of diaphragm connector elements for three-dimensional nonlinear dynamic analysis of precast concrete structures. Advances in Structural Engineering, 19(2), 187-202. doi:10.1177/1369433215624319
• Fleischman, R. B., & Zhang, D. (2015). Establishment of performance‐based seismic design factors for precast concrete floor diaphragms. Earthquake Engineering & Structural Dynamics, 45(5), 675-698. doi:10.1002/eqe.2679
• Scodeggio, A., Quaranta, G., Marano, G. C., Monti, G., & Fleischman, R. B. (2015). Optimization of force-limiting seismic devices connecting structural subsystems. COMPUTERS & STRUCTURES, 162, 16-27.
• Wan, G. e., Zhang, D., Fleischman, R. B., & Naito, C. J. (2015). A coupled connector element for nonlinear static pushover analysis of precast concrete diaphragms. ENGINEERING STRUCTURES, 86, 58-71.
• Belleri, A., Schoettler, M. J., Restrepo, J. I., & Fleischman, R. B. (2014). Dynamic Behavior of Rocking and Hybrid Cantilever Walls in a Precast Concrete Building. ACI STRUCTURAL JOURNAL, 111(3), 661-671.
• Fleischman, R. B., Restrepo, J. I., Pampanin, S., Maffei, J. R., Seeber, K., & Zahn, F. A. (2014). Damage Evaluations of Precast Concrete Structures in the 2010-2011 Canterbury Earthquake Sequence. EARTHQUAKE SPECTRA, 30(1), 277-306.
• Fleischman, R. B., Restrepo, J. I., Naito, C. J., Sause, R., Zhang, D., & Schoettler, M. (2013). Integrated analytical and experimental research to develop a new seismic design methodology for precast concrete diaphragms. Journal of Structural Engineering (United States), 139(7), 1192-1204.
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  Abstract: A new seismic diaphragm design methodology has been developed for precast concrete floor diaphragms. The knowledge required to create the design methodology was obtained through an integrated analytical and experimental research project using two Network for Earthquake Engineering Simulation (NEES) equipment sites. The activities of the project involved a sequence of integrated research tasks that systematically developed knowledge about diaphragm behavior from the reinforcement detail level to the structural system level. These tasks included the use of state-of-the-art experimental techniques made possible through the NEES facilities including hybrid simulation and large-scale shake table tests. Such techniques were crucial to the research as the complex behavior of precast diaphragms is not well described by simple analytical models or idealized experiments. Valuable industry oversight in the planning, execution, and technology transfer stages of the project guided the research activities, including a design framework established at the outset of the project. This paper describes the research project approach, activities, and outcomes. © 2013 American Society of Civil Engineers.
• Zhang, D., Fleischman, R. B., Restrepo, J. I., Naito, C. J., Sause, R., & Schoettler, M. (2013). Integrated Analytical and Experimental Research to Develop a New Seismic Design Methodology for Precast Concrete Diaphragms. Journal of Structural Engineering, 139(7), 1192-1204. doi:10.1061/(asce)st.1943-541x.0000734
• Federico, G., Fleischman, R. B., & Ward, K. M. (2012). Buckling control of cast modular ductile bracing system for seismic-resistant steel frames. Journal of Constructional Steel Research, 71, 74-82.
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  Abstract: The buckling behavior of a new ductile bracing concept for steel structures is examined. The system makes use of cast components introduced at the ends and the center of the brace to produce a special bracing detail with reliable strength, stiffness and deformation capacity. The system takes advantage of the versatility in geometry offered by the casting process to create configurations that eliminate non-ductile failure modes in favor of stable inelastic deformation capacity. This paper presents analytical research performed to determine the buckling strength and buckling direction of the bracing element based on the geometries of the cast components. Limiting geometries are determined for the cast components to control the buckling direction. Design formulas for buckling strength are proposed. © 2011 Elsevier Ltd. All rights reserved.
• Fleischman, R. B., Restrepo, J. I., Maffei, J. R., & Seeber, K. (2012). Preview of PCI's New Zealand earthquake reconnalssanoe team report. PCI Journal, 57(1), 42-46.
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  Abstract: Moment-resisting frames have been the most common seismic-force-resisting system for tall buildings in New Zealand. A beam sidesway mechanism, in which plastic hinges form in the beams due to strong columns and weak beams, is the preferred nonlinear mechanism. Structural precast concrete walls have also been used to provide seismic resistance in medium-rise buildings in New Zealand. In some cases precast concrete walls and frames are combined to form dual systems. These walls are designed to develop a plastic hinge at the base. New Zealand lies on the Pacific Rim and has a history of strong earthquakes. However, Christchurch is about 240 km from the nearest known major fault, and thus was not expected to experience a large earthquake. The exterior moment-resisting frame of the PricewaterhouseCoopers building performed as intended, forming the desired flexural plastic hinges at the ends of the beams.
• Wan, G. C., Fleischman, R. B., & Zhang, D. (2012).

  Effect of Spandrel Beam to Double Tee Connection Characteristic on Flexure-Controlled Precast Diaphragms

  . Journal of Structural Engineering, 138(2), 247-257. doi:10.1061/(asce)st.1943-541x.0000426
• Wan, G., Fleischman, R. B., & Zhang, D. (2012). Effect of spandrel beam to double tee connection characteristic on flexure-controlled precast diaphragms. Journal of Structural Engineering, 138(2), 247-257.
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  Abstract: Precast spandrel beams are often used on the perimeter of precast buildings to support the precast floor units. These elements are typically not considered part of the lateral force resisting system. However, the presence of the spandrel beams in the floor system may modify the strength, stiffness, and deformation capacity of the precast floor diaphragm. The nature of this response is highly dependent on the characteristics of the details connecting the spandrel to the precast floor system. These details are often welded connections used primarily for erection stability and designed without diaphragm action in mind. With emerging design methodologies for precast diaphragms requiring better-defined performance, the impact of the spandrel beams must be accounted for. Accordingly, analytical research is presented here that examines the effect of spandrel-beam-connecting details on the global characteristics and local demands of a flexure-controlled precast floor diaphragm. Design recommendations are provided. © 2012 American Society of Civil Engineers.
• Ward, K. M., Fleischman, R. B., & Federico, G. (2012). A cast modular bracing system for steel special concentrically braced frames. Engineering Structures, 45, 104-116.
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  Abstract: A Cast Modular Ductile Bracing System (CMDB) is under development as an alternative to special concentrically braced frames. The CMDB system introduces cast components at the ends and center of the brace in an attempt to produce a system with reliable strength, stiffness, and deformation capacity. A cruciform cross-section has been chosen for the cast component geometry, which is specially detailed to enhance energy dissipation and increase low cycle fatigue life thereby reducing the likelihood of fracture. In this paper, capacity design parameters are established that describe the axial strength and flexural strength of the cast components relative to the main hollow structural section member. These parameters are varied in 2D finite element models to understand the nature of the system and identify the best performing designs. 3D FE models of the CMDB system and a typical special concentrically braced frame, in combination with fracture indices, are used to compare the expected low cycle fatigue life of the two systems. © 2012 Elsevier Ltd.
• Zhang, D., Fleischman, R. B., Naito, C. J., & Ren, R. (2011). Experimental evaluation of pretopped precast diaphragm critical flexure joint under seismic demands. Journal of Structural Engineering, 137(10), 1063-1074.
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  Abstract: Precast concrete diaphragm seismic response is examined in experimental research integrating model-based simulation with physical testing. The experimental substructure is the diaphragm critical flexural region of a prototype precast parking structure. This region is expected to undergo significant inelastic flexural deformation, while potentially nonductile regions remain elastic on the basis of capacity design rules from an emerging design methodology. The physical test is conducted at half-scale. The test specimen is detailed using diaphragm reinforcement intended to meet deformability requirements. Predetermined displacement histories are applied to the test specimen on the basis of nonlinear transient dynamic analyses of the prototype structure. The loading history is applied by a test fixture capable of simultaneously providing shear, axial, and moment to the joint. Moment strength, stiffness, rotational deformation capacity, and progressive damage are examined under a sequence of increasing intensity earthquakes. Design recommendations are provided. © 2011 American Society of Civil Engineers.
• Zhang, D., Fleischman, R. B., Naito, C., & Ren, R. (2011).

  Experimental Evaluation of Pretopped Precast Diaphragm Critical Flexure Joint under Seismic Demands

  . Journal of Structural Engineering, 137(10), 1063-1074. doi:10.1061/(asce)st.1943-541x.0000352
• Schoettler, M. J., Belleri, A., Dichuan, Z., Restrepo, J. I., & Fleischman, R. B. (2009). Preliminary results of the shake-table testing for the development of a diaphragm seismic design methodology. PCI Journal, 54(1), 100-124.
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  Abstract: This paper reports the design, construction, and preliminary results of a three-story precast concrete building built at half scale and tested under input ground motions on the George B. Brown Jr. Network of Earthquake Engineering Simulation's Large High-Performance Outdoor Shake Table at the University of California, San Diego. This building was tested in support of the development of a diaphragm seismic design methodology project funded by the Precast/Prestressed Concrete Institute, the National Science Foundation, and the Charles Pankow Foundation and developed jointly by the University of Arizona; University of California, San Diego; Lehigh University; and the precast, prestressed concrete industry. The test structure had a rectangular plan and incorporated a pretopped double-tee diaphragm with welded chords, a noncomposite-topped diaphragm on hollow-core units, and a composite-topped diaphragm on double-tee floor units. The unique research opportunity of testing a complete structural system at large scale was exploited to the fullest extent by subjecting the building to 16 significant-input ground motions while 640 sensors dynamically recorded the development of a number of damage-limit states in various elements and connections in the structure.
• Fleischman, R. B., & Wan, G. (2007). Appropriate Overstrength of Shear Reinforcement in Precast Concrete Diaphragms. Journal of Structural Engineering, 133(11), 1616-1626. doi:10.1061/(asce)0733-9445(2007)133:11(1616)
• Fleischman, R. B., & Wan, G. (2007). Appropriate overstrength of shear reinforcement in precast concrete diaphragms. Journal of Structural Engineering, 133(11), 1616-1626.
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  Abstract: Current precast concrete diaphragm design may not necessarily protect the diaphragm from a nonductile shear failure in an overload situation. As evidence exists that diaphragms can attract large inertial loads during strong ground motion, emerging design methodologies are aiming to develop the diaphragm flexural strength. However, the performance target desirable or achievable in design may depend on a number of other factors. An analytical study examines the performance of precast diaphragms with different shear strength relative to design (flexural) strength, termed here "shear reinforcement overstrength." The objective of the study is to determine the required shear reinforcement overstrength in the precast diaphragm to produce certain performance targets. Appropriate shear reinforcement overstrength design factors are proposed in terms of a number of key parameters related to diaphragm geometry and the properties of the diaphragm reinforcing details. © 2007 ASCE.
• Fleischman, R. B., Naito, C. J., Restrepo, J., Sause, R., Ghosh, S. K., GeWan, ., Schoettler, M., & Cao, L. (2007). Charles C. Zollman Award - Robert B. Fleischman, Clay J. Naito, Jose Restrepo, Richard Sause, S. K. Ghosh, GeWan, Matt Schoettler, Liling Cao. PCI JOURNAL, 52(1), 61-62.
• Fleischman, R. B., Palmer, N. J., Wan, G. C., & Li, X. (2007).

  Cast Modular Panel Zone Node for Steel Special Moment Frames. II: Experimental Verification and System Evaluation

  . Journal of Structural Engineering., Vol. 133(No. 10), pp. 1393-1403. doi:10.1061/(asce)0733-9445(2007)133:10(1404)
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  A panel zone dissipator modular node (PZ-MN) has been developed for use in seismic-resistant steel moment frames. The PZ-MN is configured directly for optimal seismic performance through a casting process. The PZ-MN dissipates energy through stable yielding of the panel zone. This objective is accomplished by mitigating the effects of panel zone distortion on surrounding members and connections. Field welds are removed from critical cross sections and demands are redirected in noncritical paths. A cast piece easily accommodates the geometries and features to meet this objective. The PZ-MN was developed through a comprehensive analytical research program and verified through full-scale experimentation. This paper describes the analytical development stage. Investigation of trial configurations, key parameters, and enhancements resulted in a prototype design for the PZ-MN. The PZ-MN prototype shows the potential for excellent seismic performance, including under the combined effects of lateral and gravity load. This performance is experimentally verified in a companion paper.
• Fleischman, R. B., Palmer, N. J., Wan, G., & Xuejun, L. i. (2007). Cast modular panel zone node for steel special moment frames. II: Experimental verification and system evaluation. Journal of Structural Engineering, 133(10), 1404-1414.
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  Abstract: A companion paper has described the analytical development of a panel zone dissipator modular node (PZ-MN) prototype for use in seismic-resistant steel moment frames. The PZ-MN dissipates energy through stable yielding of its panel zone, an objective accomplished by mitigating the effects of panel zone distortion on the surrounding members. The PZ-MN is configured directly for this purpose through a casting process. This paper presents experimental verification of the PZ-MN prototype. This process relied heavily on interaction with industry partners to create a castable and constructible shape. The PZ-MN prototype was cast at full scale, fabricated and subjected to FEMA-350 qualification testing with and without gravity load. The PZ-MN prototype exhibited remarkable performance, greatly exceeding qualifying drift angles and possessing exceptional hysteretic characteristics. Using models based on these characteristics, frame performance is evaluated. Design guidelines are given on the basis of the analytical and experimental results. © 2007 ASCE.
• Fleischman, R. B., Sumer, A., & Li, X. (2007).

  Development of Modular Connections for Steel Special Moment Frames

  . Journal of Structural Engineering, Vol. 133(No. 10), pp. 1393-1403; pp. 1404-1414. doi:10.1061/40700(2004)88
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  Modular connections have been developed for use in seismic-resistant steel moment frames. The connections are configured specifically for optimal seismic response through the use of a steel casting process. The impetus for developing these connections is the recently discovered susceptibility of steel special moment frames during earthquakes. Major features of the modular connections are the minimization of stress/strain and the removal of the field weld from the critical cross-section. To date, two prototypes had been fully developed: (1) a panel zone dissipator modular node (PZ-MN); and (2) a bolted modular connector (MC). The PZ-MN dissipates energy through stable panel zone yielding without column kinking and weld distress; the MC dissipates energy in a variable-arm connector that minimizes plastic strain demand and eliminates prying forces. The prototypes were developed through a comprehensive analytical program using nonlinear finite element (FE) analysis. Full-scale prototypes were cast and tested under the FEMA-350 protocol. These connections exhibited stable energy dissipation and remarkable ductility.
• Fleischman, R. B., Xuejun, L. i., Pan, Y., & Sumer, A. (2007). Cast modular panel zone node for steel special moment frames. I: Analytical development. Journal of Structural Engineering, 133(10), 1393-1403.
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  Abstract: A panel zone dissipator modular node (PZ-MN) has been developed for use in seismic-resistant steel moment frames. The PZ-MN is configured directly for optimal seismic performance through a casting process. The PZ-MN dissipates energy through stable yielding of the panel zone. This objective is accomplished by mitigating the effects of panel zone distortion on surrounding members and connections. Field welds are removed from critical cross sections and demands are redirected in noncritical paths. A cast piece easily accommodates the geometries and features to meet this objective. The PZ-MN was developed through a comprehensive analytical research program and verified through full-scale experimentation. This paper describes the analytical development stage. Investigation of trial configurations, key parameters, and enhancements resulted in a prototype design for the PZ-MN. The PZ-MN prototype shows the potential for excellent seismic performance, including under the combined effects of lateral and gravity load. This performance is experimentally verified in a companion paper. © 2007 ASCE.
• Sumer, A., Fleischman, R. B., & Hoskisson, B. E. (2007). Development of a cast modular connector for seismic-resistant steel moment frames part 1: Prototype development. Engineering Journal, 44(3), 195-211.
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  Abstract: An analytical development of a working prototype of the modular connector (MC) for seismic-resistant steel moment frames is described in the various stages of development process including interdisciplinary industry meetings at the conceptual stages, extensive analytical research, castability, and constructability studies. MC design for a reliable connection plastic rotation capacity is provided by choosing a limit of useful connection rotation at 0.05 radian. The alpha prototype of MC exhibit the desired behavior as plastic zone causing lower plastic strain in the MC and the stiffness of the base creates significantly lower plastic strain in the bolt threads and no plastic behavior in the bolt shank. Compression pad is provided to transmit the steel beam flange compressive loads directly to the column as the MC cycles between tension and compression loading during seismic response.
• Sumer, A., Fleischman, R. B., & Palmer, N. J. (2007). Development of a cast modular connector for seismic-resistant steel moment frames part 2: Experimental verification. Engineering Journal, 44(3), 213-231.
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  Abstract: The prototyping and experimental verification of the modular connector (MC) Beta prototype model, including an examination of the connector's cyclic performance, was described. The Beta prototype was provided by iterating between structural and thermodynamical/fluid flow finite element analysis through the electronic exchange of three-dimensional solid geometry CAD files. The MC Beta prototype is evaluated at full-scale in full beam-to-column connections under the AISC prototype and referenced to a joint in a prototype structure. The experimental results of the scaled MC Beta prototype after casting detailed that transmits beam flange compressive forces directly to the column during cyclic response. The results also show that the MC Beta achieves a high monotonic ductility and suffer no distress in a certain inch of diameter ASTM A325 bolts.
• Fleischman, R. B., & Sumer, A. (2006). Optimum Arm Geometry for Ductile Modular Connectors. Journal of Structural Engineering, 132(5), 705-716. doi:10.1061/(asce)0733-9445(2006)132:5(705)
• Fleischman, R. B., & Sumer, A. (2006). Optimum arm geometry for ductile modular connectors. Journal of Structural Engineering, 132(5), 705-716.
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  Abstract: A cast modular connector (MC) has been developed for use as an energy dissipating detail in seismic-resistant bolted steel moment frames. The MC relies on a series of variable section elements (arms) to minimize plastic strain demand and a stiff end region joined by a base to virtually eliminate bolt prying forces and provide a hysteresis characteristic absent of degradation. The MC was developed through a comprehensive program that included heavy industry partner involvement, analytical research, and experimental verification. This paper describes the portion of the analytical research focused on establishing the optimum geometry for the energy-dissipating arm elements. Key parameters were evaluated through parametric studies using nonlinear (material and geometry) finite element analysis and supported by basic theoretical models. The outcome was a set of optimum geometric ratios covering width reduction, length to thickness, aspect ratio, and fillet radius. A MC prototype was cast on the basis of these recommendations. These prototypes were tested under monotonic and cyclic loading and exhibited remarkable ductility, far exceeding qualifying rotational capacities. © ASCE.
• Fleischman, R. B., Naito, C. J., Restrepo, J., Sause, R., Ghosh, S. K., Wan, G., Schoettler, M., & Cao, L. (2005). Seismic design methodology for precast concrete diaphragms part 2: Research program. PCI Journal, 50(6), 14-31.
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  Abstract: The Precast/Prestressed Concrete Institute (PCI) is conducting a large "area of emphasis" project to develop an industry-endorsed comprehensive seismic design methodology for precast concrete floor diaphragms. A multi-university research team from the University of Arizona (UA), Lehigh University (LU), and the University of California San Diego (UCSD) has been selected to perform this collaborative research. An active industry task group is overseeing the planning and execution phases of the research. These groups comprise the DSDM (Diaphragm Seismic Design Methodology) Consortium. The DSDM Consortium research closely integrates finite element analyses of the diaphragm at UA with full-scale reinforcing detail experiments at LU and shaking table system tests at UCSD. The purpose of this and a companion paper, published in the September-October 2005 issue of the PCI JOURNAL, is to outline the foundation for this research and provide context for the technical papers to follow as well as the eventual design methodology. The earlier companion paper described the underlying design philosophy and the resulting design framework that will serve as a basis for the emerging design methodology. This paper focuses on the research program itself, including the integrated research approach, the project's physical scope, and the specific analytical and experimental research activities.
• Fleischman, R. B., Naito, C., Restrepo, J. I., Sause, R., & Ghosh, S. (2005).

  Seismic Design Methodology for Precast Concrete Diaphragms Part 1: Design Framework

  . Precast/Prestressed Concrete Journal, Vol. 50(n5). doi:10.15554/pcij.09012005.68.83
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  The Precast/Prestressed Concrete Institute is conducting an area of emphasis: research project on precast concrete diaphragms. The project has been called Diaphragm Seismic Design Methodology (DSDM). The purpose of this paper is to outline the foundation for the research by presenting the underlying design philosophy and resulting design framework that will serve as the basis for the technical papers to follow and the eventual design methodology at the projected conclusion. The objective of the DSDM project is to develop an industry endorsed design methodology for precast/prestressed concrete diaphragms including: the forces, displacements, and deformations for which the diaphragm should be designed; the diaphragm reinforcing details that can provide this performance; and the required stiffness of the diaphragm relative to the primary lateral force resisting system elements.
• Fleischman, R. B., Restrepo, J., Ghosh, S. K., Naito, C. J., & Sause, R. (2005). Seismic design methodology for precast concrete diaphragms part 1: Design framework. PCI Journal, 50(5), 68-83.
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  Abstract: The DSDM (Diaphragm Seismic Design Methodology) Consortium is conducting a research project on precast concrete diaphragms. The project aims at developing an industry-endorsed comprehensive seismic design methodology for precast/prestressed concrete floor diaphragms. The methodology will aim to satisfy design requirements at three levels within the structure: the diaphragm level, the joint level, and the detail level. A desirable inelastic mechanism is achieved when the seismic input level exceeds the DBE level by using capacity design concepts to produce a hierarchy of design strengths at the joint and detail level.
• Farrow, K. T., & Fleischman, R. B. (2003). Effect of Dimension and Detail on the Capacity of Precast Concrete Parking Structure Diaphragms. PCI Journal, 48(5), 46-61.
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  Abstract: Floor systems in precast concrete parking structures are intended to provide diaphragm action between elements of the lateral loadresisting system during seismic response. Investigations stemming from recent poor seismic performance of some of these structures have raised significant design issues related to the diaphragm. These issues include the possibility of larger-than-expected lateral forces, questionable strength and ductility in joints at critical locations, and the potential for large drift demand on the gravity system due to excessive diaphragm flexibility. A PCI Daniel P. Jenny Research Fellowship has examined the behavior of precast concrete parking structure diaphragms. In this paper, the results of nonlinear static analyses of topped and pretopped diaphragms are presented. These results reveal the effect of structural dimension and construction details on the diaphragm service level stiffness and ultimate capacity. A companion paper ("Seismic Design Recommendations for Precast Concrete Diaphragms in Long Floor Span Construction," to appear in the next issue of the PCI JOURNAL) will provide seismic design guidelines for long span precast diaphragms. In that paper, the results presented here will be interpreted with respect to expected seismic demands, as established for flexible diaphragm structures in parallel research.
• Fleischman, R. B., & Farrow, K. T. (2003).

  Effect of Structural Configuration and Diaphragm Detail on the Seismic Response of Precast Parking Structures

  . PCI Journal, Vol. 48(No. 5). doi:10.15554/pci.rr.seis-014
• Fleischman, R. B., & Farrow, K. T. (2003).

  Seismic Design Recommendations for Precast Concrete Diaphragms in Long Floor Span Construction

  . PCI Journal, Vol. 48(No. 6). doi:10.15554/pcij.11012003.46.62
• Fleischman, R. B., & Farrow, K. T. (2003). EFFECT OF DIMENSION AND DETAIL ON THE CAPACITY OF PRECAST CONCRETE PARKING STRUCTURE DIAPHRAGMS. PCI Journal, 48(5), 46-61. doi:10.15554/pcij.09012003.46.61
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  The paper presents a study that focuses on diaphragms in precast parking structures. The analytical study presented represents an examination of precast concrete diaphragm capacity. In this stage, the global stiffness, strength, and ductility capacity of the diaphragm are examined with respect to structural dimensions and diaphragm reinforcing details. Many of the findings can equally be appplied to long-span precast concrete diaphgrams in general. The paper presents conclusions that pertain to internal load paths, service level behavior, and ultimate capacity of precast parking structure diaphgrams. The conclusions are qualitative in nature; the quantitative realizations of these conclusions are presented in a companion paper recommendations.
• Fleischman, R. B., & Farrow, K. T. (2003). Seismic design recommendations for precast concrete diaphragms in long floor span construction. PCI Journal, 48(6), 46-62.
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  Abstract: The paper "Effect of Dimension and Detail on the Capacity 0f Precast Concrete Parking Structure Diaphragms," published in the September-October 2003 PCI JOURNAL, presented the effect of structural dimension and construction detail on the capacity of precast concrete floor diaphragms, using parking structures as the prototype structure. Parallel research by the authors has established seismic demands for flexible diaphragm structures. In this paper, the findings of these two research steps are interpreted to propose design recommendations for precast concrete diaphragms in long floor span construction. These recommendations include provisions for diaphragm design strength, allowable flexibility, and ductility capacity based on seismic performance requirements. The provisions are incorporated into a design procedure employing performance-based design concepts. Application of the procedure is shown in a design example (Appendix B) for precast parking structure diaphragms. Research on this subject will continue over the next several years, with funding provided by both governmental and industry organizations.
• Sumer, A., & Fleischman, R. B. (2003). DEVELOPMENT OF MODULAR CAST STEEL CONNECTIONS FOR SEISMIC-RESISTANT BUILDING FRAMES. Astm Standardization News, 31(1), 40-43.
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  Modular cast steel connections that exploit the ductility of steel are being developed for use in seismic-resistant building frames. An effective earthquake-resistant connection design should be based on a combination of weld fracture mitigation measures and the reduction/redirection of stress flow. The modular connection concept attempts to address these needs through the creation of new connection forms specifically configured for seismic performance to ensure the connections possess the required strength, ductility and material isotropy. A modular node and a modular connector have been developed through solid modeling and nonlinear finite element analysis, and prototypes have been cast. The connections have exhibited superior ductility, reliability and energy dissipation characteristics in both analytical simulations and full-scale testing.
• Fleischman, R. B., Farrow, K. T., & Eastman, K. (2002).

  Seismic Performance of Perimeter Lateral-System Structures with Highly Flexible Diaphragms

  . Earthquake Spectra, Professional Journal of the Earthquake Engineering Research Institute (EERI), Vol. 18(No. 2), p. 251-286. doi:10.1193/1.1490547
• Fleischman, R. B., Farrow, K. T., & Eastman, K. (2002). Seismic performance of perimeter lateral-system structures with highly flexible diaphragms. Earthquake Spectra, 18(2), 251-286.
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  Abstract: Building structures are typically designed using the assumption that the floor systems serve as a rigid diaphragm between the vertical elements of the lateral force-resisting system (lateral system). However, perimeter lateral-system structures with long floor spans possess diaphragms that behave quite flexibly. Difficulty can exist in predicting diaphragm force demand in these structures. Thus, current design may provide insufficient strength to maintain elastic diaphragm response. Inelastic diaphragm response exacerbates the effects of diaphragm flexibility. Such response may lead to poor seismic performance, including nonductile diaphragm failure or structural instability due to high drift demands in the gravity system. An analytical study was performed to determine the effect of diaphragm flexibility and strength on the seismic performance of perimeter lateral-system structures with highly flexible diaphragms. Nonlinear transient analyses were performed using ground motions suites corresponding to multiple levels of hazard for high seismic zones. Design recommendations for flexible diaphragms are presented.
• Fleischman, R. B., & Farrow, K. T. (2001). Dynamic behavior of perimeter lateral-system structures with flexible diaphragms. Earthquake Engineering and Structural Dynamics, 30(5), 745-763.
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  Abstract: Building structures are typically designed using the assumption that the floor systems serve as a rigid diaphragm between the vertical elements of the lateral load-resisting system. However, long-floor span structures with perimeter lateral load-resisting systems possess diaphragms which behave quite flexibly. The dynamic behaviour of such structures is dissimilar to the behavior expected of typical structures. This difference can lead to unexpected force and drift patterns. If force levels are sufficiently under-estimated, inelastic diaphragm behaviour can occur, exacerbating the effects of diaphragm flexibility. Such response may lead to a non-ductile diaphragm failure or structural instability due to high drift demands in the gravity system. Analytical models were developed which capture the diaphragm flexibility of structures with long-floor spans and perimeter lateral-systems. Modal examination and time-history analyses were performed to determine the effect of diaphragm flexibility and diaphragm inelastic behaviour on the dynamic behaviour of these structures. Copyright © 2001 John Wiley & Sons, Ltd.
• Fleischman, R. B., Sause, R., Pessiki, S., & Rhodes, A. B. (1998).

  Seismic Behavior of Precast Parking Structure Diaphragms

  . Precast/Prestressed Concrete Journal,, Vol. 43(No. I), p. 38-53. doi:10.15554/pcij.01011998.38.53
• Fleischman, R. B., Sause, R., Pessiki, S., & Rhodes, A. B. (1998). Seismic behavior of precast parking structure diaphragms. PCI Journal, 43(1), 38-53.
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  Abstract: This paper presents a study of the role of diaphragm deformations in the seismic performance of precast parking structures. A prototype parking structure typical of structures in the Los Angeles area prior to the 1994 Northridge earthquake was studied. Nonlinear static analyses of the diaphragms and shear walls were conducted. The response of the diaphragms and shear walls in these analyses provided stiffness and strength properties for a dynamic analysis model of the structure. Significant issues related to the role of diaphragm deformations in the seismic performance of precast parking structures were identified. These include large drift demands on the gravity load system due to excessive diaphragm deformations; shear wall locations that cause the diaphragms to twist in plan, amplifying these deformations; and cross sections in critical locations in the diaphragms that have insufficient strength.
• Sause, R., Rhodes, A. B., Pessiki, S., & Fleischman, R. B. (1996). Seismic Behavior of Precast Parking Structure Diaphragms. Building an International Community of Structural Engineers, 1139-1146.
• Fleischman, R. B., Chasten, C. P., Lu, L., & Driscoll, G. C. (1991). Top-and-seat-angle connections and end-plate connections: snug vs. fully pretensioned bolts. Engineering Journal, 28(1), 18-28.
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  Abstract: The effect of partially pretensioned bolts has been examined through research conducted at the ATLSS center of Lehigh University. Extended end-plate and top-and-seat-angle connections incorporating fully pretensioned and snug-tight bolts were tested. Fully pretensioned bolts were tightened to 70% of their ultimate strength (as specified by AISC), and snug bolts were tightened to between 30% and 40% of their ultimate strength.† A W27×94 beam section was connected to a W14×193 column section for the tests considered. All material was 50 ksi steel, and A325 1-in. and 1 1/8-in. diameter bolts were used for all connections. Snug-tightened end-plate connections performed essentially the same as their fully pretensioned counterparts. Snug connections were nearly as stiff as the fully pretensioned connections at moderate loads, and the ultimate strength was the same for either case. Snug-tight connections actually behaved stiffer during the course of reversal loading. Top-and-seat-angle connections were designed to resist moment by using equally large angles attached at the top and bottom beam flanges. The snug-tight connection for multiple bolt rows behaved stiffer and stronger than its fully pretensioned counterpart. Two modes of behavior are proposed for these cases. The snug-tight connection also reacted less adversely to load reversal, and its load-deformation response remained linear over a larger range of loading.

Proceedings Publications

• Blasi, G., Perrone, D., Aiello, M. A., & Fleischman, R. B. (2021, Sept). Retrofit of Masonry Infills: Local Interaction with Reinforced Concrete Frames. In 17th World Conference on Earthquake Engineering, 17WCEE.
• Bokhari, I., Browne, S., Young, H., & Fleischman, R. B. (2022, March). Experimental Evaluation of Casting Quality and Welded Interfaces for Cast Steel Nodes to Round HSS. In North American Steel Construction Conference (NASCC): The Steel Conference.
• Fleischman, R. B., Sause, R., Ricles, J., Uang, C. M., Li, C. H., Moya, J., & Duke, J. (2021, Sept). ANALYTICAL AND EXPERIMENTAL INVESTIGATION OF SEISMIC FLOOR AND ROOF COLLECTORS IN STEEL BUILDING STRUCTURES. In 17th World Conference on Earthquake Engineering, 17WCEE, 1-11.
• Fleischman, R. B., Sause, R., Ricles, J., Uang, C. M., Moya, J., Dongzhi, G., Li, C. H., & Duke, J. (2020, June). ANALYTICAL AND EXPERIMENTAL INVESTIGATION OF STEEL SEISMIC COLLECTOR CONNECTIONS. In IX Connections Workshop, AISC-ECCS Workshop on Connections in Steel Structures, 1-11.
• Li, C. H., Uang, C. M., & Fleischman, R. B. (2022, July). Shake Table Tests on Seismic Response of Collectors in Steel Buildings. In 12th National Conference on Earthquake Engineering (12NCEE).
• Li, C. H., Uang, C. M., & Fleischman, R. B. (2022, July). Strain Aging Effects on Seismic Response of Buckling Restrained Braces. In 12th National Conference on Earthquake Engineering (12NCEE).
• Moya, J., Fleischman, R. B., Maldonado, C., & Bokhari, I. (2020, December). ANALYTICAL AND EXPERIMENTAL INVESTIGATION OF CASTING QUALITY EFFECT ON DUCTILE FRACTURE PERFORMANCE. In SFSA Technical & Operations Conference, 1-9.
• Pandey, S., Fleischman, R. B., Sause, R., Ricles, J., & Uang, C. M. (2022, July). Behavior of Seismic Collectors in Steel Building Structures. In 12th National Conference on Earthquake Engineering (12NCEE).
• Park, S., Bokhari, I., Alnuaimi, H., Amjad, U., Fleischman, R. B., & Kundu, T. (2022, April). Inspection of steel tube welded joint using nonlinear ultrasonic technique. In SPIE Smart Structures + Nondestructive Evaluation, 2022, Volume 12048.
• Tsampras, G., Sause, R., Fleischman, R. B., & Restrepo, J. (2022, July). Practical force-limiting deformable connections in buildings with rocking base mechanism and limited higher-mode responses. In 12th National Conference on Earthquake Engineering (12NCEE), Reimagining Risk and Resilience.
• Park, S., Bokhari, I., Alnuaimi, H., Amjad, U., Fleischman, R. B., & Kundu, T. (2022, April).

  Inspection of steel tube welded joint using nonlinear ultrasonic technique

  . In Proceedings of the SPIE, Volume 12048,, pp. 10.1117/12.2611920.
• Tsampras, G., Sause, R., Fleischman, R. B., Restrepo, J., Maffei, J., & Mar, D. (2015, April). Experimental validation of an earthquake resistant building system to control floor accelerations . In 2015 ASCE Structures Congress.
• Agarwal, A., Lizarraga, D., Beedle, M., Li, C. H., Fleischman, R. B., Sause, R., Ricles, J. M., & Uang, C. (2018, June 25-29).

  Investigation of seismic performance of collectors in steel building structures

  . In Eleventh U.S. National Conference on Earthquake Engineering: Integrating Science, Engineering & Policy,.
• Agarwal, A., Lizarraga, D., Beedle, M., Li, C., Fleischman, R. B., Sause, R., Ricles, J., & Uang, C. (2018, June). INVESTIGATION OF SEISMIC PERFORMANCE OF COLLECTORS IN STEEL BUILDING STRUCTURES. In Eleventh U.S. National Conference on Earthquake Engineering, Integrating Science, Engineering & Policy.
• Kuzucu, ,,, I. B., Fleischman, R. B., Zhang, D., Scheidegger, C. E., & Wei, Y. (2018, June). VERTICAL DISTRIBUTION OF FORCE-CONTROLLED SEISMIC RESPONSES IN MULTI-STORY RC BUILDINGS. In Eleventh U.S. National Conference on Earthquake Engineering, Integrating Science, Engineering & Policy.
• Kuzucu, I. B., Fleischman, R. B., Zhang, D., Scheidegger, C., & Wei, Y. (2018, June 25-29).

  Vertical distribution of force-controlled seismic responses in multistory RC buildings

  . In Eleventh U.S. National Conference on Earthquake Engineering: Integrating Science, Engineering & Policy,.
• Tsampras, G., Sause, R., Fleischman, R. B., Restrepo, J., Zhang, Z., Shakya, U., Zhang, D., Maffei, J., & Mar, D. (2018, June). EXPERIMENTAL STUDY OF CONNECTION BETWEEN FLOOR SYSTEM AND LATERAL FORCE RESISTING SYSTEM. In Eleventh U.S. National Conference on Earthquake Engineering, Integrating Science, Engineering & Policy.
• Zhang, Z., Nema, A., Guerrini, G., Shakya, U., Tsampras, G., Fleischman, R. B., Restrepo, J., Sause, R., Zhang, D., Maffei, J., Mar, D., & Monti, G. (2018, June). AN INERTIAL FORCE-LIMITING FLOOR ANCHORAGE SYSTEM FOR LOW-DAMAGE BUILDING STRUCTURES. In Eleventh U.S. National Conference on Earthquake Engineering, Integrating Science, Engineering & Policy.
• Zhang, Z., Zhang, D., Tsampras, G., Shakya, U., Sause, R., Restrepo, J. I., Mar, D., Maffei, J., & Fleischman, R. B. (2018, June). Experimental study of connection between floor system and lateral force resisting system. In Eleventh U.S. National Conference on Earthquake Engineering.
• Zhang, Z., Zhang, D., Tsampras, G., Shakya, U., Sause, R., Restrepo, J. I., Nema, A., Monti, G., Mar, D., Maffei, J., Guerrini, G., & Fleischman, R. B. (2018, June). An inertial force-limiting floor anchorage system for lowdamage building structures. In 11th US National Conference on Earthquake Engineering, 11.
• Arviso, D., Fleischman, R. B., Anvar, R., & Boroski, K. (2017, April). Analytical Evaluation of Precast Concrete Structures Resistance to Disproportionate Collapse: Methodology Development. In ASCE Structures Congress.
• Fleischman, R. B., Agarwal, A., Ayyad, H. M., Sause, R., Ricles, J. M., & Uang, C. M. (2017, July 29-Aug 2).

  Seismic collectors in composite steel deck diaphragms

  . In COMPOSITE CONSTRUCTION VIII.
• Fleischman, R. B., Agarwal, A., Ayyad, H., Sause, R., Uang, C., & Ricles, J. (2017, July). Seismic Collectors in Composite Steel Deck Diaphragms. In COMPOSITE CONSTRUCTION VIII.
• Tsampras, G., Sause, R., Fleischman, R. B., & Restrepo, J. I. (2017, April). Experimental Evaluation of a Deformable connection for eartquake-resistant building systems. In ASCE Structures Congress,.
• Fleischman, R. B., Agarwal, A., Walsh, A. T., & Valdez, L. F. (2016, May). CHARACTERIZATION OF LOAD PATHS IN COMPOSITE STEEL DECK DIAPHRAGMS AND COLLECTORS. In AISC Workshop, International Workshop on Connections in Steel Structures 2016, CONNECTIONS VIII.
• Shakya, U., Fleischman, R. B., & Blaisdell, M. L. (2016, April). Challenges and possible solutions for building back better in Nepal. In INTERNATIONAL CONFERENCE ON EARTHQUAKE ENGINEERING AND POST DISASTER RECONSTRUCTION PLANNING, ICEE-PDRP 2016.
• Fleischman, R. B. (2015, April). An earthquake-resistant building system to reduce floor accelerations. In 2015 NZSEE Conference, Rotorua, New Zealand.
• Fleischman, R. B. (2015, April). Inertial Force-Limiting Anchorage System for Seismic Resistant Building Structures. In 2015 ASCE Structures Congress.
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  Fleischman, R., Restrepo, J., Nema, A., Zhang, D., Shakya, U., Zhang, Z., Sause, R., Tsampras, G., and Monti, G., “Inertial Force-Limiting Anchorage System for Seismic Resistant Building Structures” (1005), 2015 Structures Congress, Portland, OR., April 23-25, 2015.
• Fleischman, R. B. (2015, November). Deformable connection for earthquake-resistant building systems November 2015. In 2015 JAEE International Symposium on Earthquake Engineering.
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  Georgios Tsampras, Richard Sause...Robert Fleischman, Dichuan Zhang Deformable connection for earthquake-resistant building systems November 2015 · 2015 JAEE International Symposium on Earthquake Engineering
• Fleischman, R., Restrepo, J., Nema, A., Zhang, D., Shakya, U., Zhang, Z., Sause, R., Tsampras, G., & Monti, G. (2015, April). Inertial Force-Limiting Anchorage System for Seismic Resistant Building Structures. In Structures Congress 2015, 1302-1313.
• Τσάμπρας, Γ., Sause, R., Fleischman, R. B., Restrepo, J. I., & Zhang, D. (2015, November 19–20).

  Deformable Connection for Earthquake-resistant Building System

  . In 2015 JAEE International Symposium on Earthquake Engineering,.
• Fleischman, R. B. (2014, July). Development of a Floor Inertial Force Limiting Anchorage System Building Seismic Response. In 10th National Conference on Earthquake Engineering.
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  D. Zhang, R. Fleischman, J. Restrepo, R. Sause, J. Maffei, D. Mar, "Development of a Floor Inertial Force Limiting Anchorage System Building Seismic Response," in 10th National Conference on Earthquake Engineering, Alaska, USA, July 2014.
• Fleischman, R. B. (2014, June). New Construction for Resilient Cities: The Argument for Low Damage and Damage Free Building Structures in the 21st Century. In U.S.-Iran Symposium on Resilient Cities.
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  Fleischman, R. B. Restrepo, J.I. Pampanin, S., Maffei, J. Seeber K., Zahn, F., (2014). “New Construction for Resilient Cities: The Argument for Low Damage and Damage Free Building Structures in the 21st Century”. U.S.-Iran Symposium on Resilient Cities. Irvine CA, June 2014
• Haase, J. S., Saunders, J. K., Geng, J., Bock, Y., Goldberg, D., Melgar, D., Restrepo, J. I., Nema, A., Fleischman, R. B., Zhang, Z., Offield, D. G., & Squibb, M. B. (2014, Dec 19-24).

  Seismogeodetic Monitoring of Structural Deformation during Shaketable Experiments

  . In American Geophysical Union (AGU) Fall Meeting, ..
• Zhang, D., Zhang, D., Fleischman, R. B., Restrepo, J. I., Restrepo, J. I., Sause, R., Maffei, J., Mar, D., Monti, G., & Zhang, D. D. (2014, July). Development of a floor inertial force limiting anchorage system building seismic response. In 10th U.S. National Conference on Earthquake Engineering: Frontiers of Earthquake Engineering, NCEE 2014, 10.
• Zhang, D., Federico, G., Telleen, K., Schellenberg, A., Fleischman, R. B., & Maffei, J. (2011, April 14-16).

  Structural Analyses to Replicate the Observed Damage to Engineered Buildings from the January 2010 Haiti Earthquake

  . In ASCE Structures Congress Proceedings.
• Zhang, D., Federico, G., Telleen, K., Schellenberg, A., Fleischman, R., & Maffei, J. (2011, January). Structural analyses to replicate the observed damage to engineered buildings from the January 2010 Haiti earthquake. In Structures Congress 2011 - Proceedings of the 2011 Structures Congress, 2285-2296.
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  Abstract: Although the majority of devastation in the January 12 2010 Haiti earthquake was from non-engineered structures, the earthquake also damaged several modern engineered buildings in the capital city of Port-au-Prince. Data gathered on the observed performance of a selection of these structures is being used for the purposes of comparison with, and calibration of, analysis-based predictions used in seismic assessment procedures. Structures were selected for investigation based on their damage state, available design information, and accessibility. These buildings are a small set of important engineered reinforced concrete structures within Port-au-Prince. The available information is being used to construct analytical models using state-of-the-art techniques for nonlinear dynamic analysis. Seismic hazard levels are being estimated by indexing to the level of demand required to bring about the observed damage. Conclusions on the efficacy of these methods are being drawn through comparisons of the predicted response to actual outcomes. The final deliverable is a report documenting the structure and design information; the post-earthquake state; the modeling techniques; analytical results/comparison and evaluation of the methods. As an interim report, this paper presents: (1) general Haiti earthquake information; (2) damage mapping of candidate structures; (3) preliminary analytical modeling. © ASCE 2011.
• Fleischman, R. B., Restrepo, J., Sause, R., Naito, C., & Ghosh, S. K. (2006, January). Development of a seismic design methodology for precast diaphragms. In 8th US National Conference on Earthquake Engineering 2006, 16, 9503-9512.
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  Abstract: The Precast/Prestressed Concrete Institute (PCI) is conducting a large "area of emphasis" project, jointly funded by National Science Foundation (NSF), with an overall objective of developing a comprehensive seismic design methodology for precast concrete floor diaphragms. A multi-university research team from the University of Arizona (UA), Lehigh University (LU) and the University of California San Diego (UCSD) is performing this collaborative research. The project's research integrates nonlinear static and dynamic finite element (FE) analyses at UA with large-scale experiments and solid modeling at LU and shaking table tests and system studies at UCSD. An active industry task group oversees the planning and execution phases of the research. The integrated research approach involves: (1) Full-scale tests of isolated details under simple load combinations to determine properties for input to FE models. (2) FE models of representative floor plans analyzed under different earthquake loading conditions. (3) Earthquake simulations of structures at different levels of seismic hazard and verified by shaking table tests. (4) Realistic loading patterns applied to full-scale precast units in a multi-component load frame, corresponding to histories at critical diaphragm locations, based on seismic demands obtained in the structural analyses, and force combinations and deformation patterns obtained in the diaphragm analyses. In the research program's first year, consensus was established on: (1) the underlying design philosophy guiding the research; (2) the physical scope of the project. The full-scale detail tests, FE analyses of diaphragms and earthquake simulations are underway. The shake table test is being planned.
• Wan, G., & Fleischman, R. B. (2006, January). Parametric study on the overstrength of shear reinforcement in untopped precast concrete diaphragms. In 8th US National Conference on Earthquake Engineering 2006, 7, 4075-4084.
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  Abstract: Current precast concrete diaphragm design may not necessarily protect the diaphragm from a non-ductile shear failure in an overload situation. As evidence exists that diaphragms can attract large inertial loads during strong ground motion, it may be advisable to develop the diaphragm flexural strength. However, the performance target desirable or achievable in design may depend on a number of other factors. An analytical study examines precast diaphragm performance for diaphragms of different shear strength relative to flexural strength over the range of several design parameters. The primary objective of the study is to determine the required shear reinforcement design overstength (relative to the flexural reinforcement) in the precast diaphragm to produce good performance. A number of key parameters are examined including diaphragm shear overstrength, diaphragm span, aspect ratio and the tension deformation capacity of reinforcing details. Copyright © (2006) by Earthquake Engineering Research Institute All rights reserved.
• Fleischman, R. B., & Hoskisson, B. (2000, January). Modular connectors for seismic resistant steel moment frames. In Structures Congress 2000: Advanced Technology in Structural Engineering, 103.
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  Abstract: Modular connectors are being developed for use in seismic-resistant steel moment frames. The connectors are engineered specifically to meet performance requirements corresponding to optimal seismic response. The versatility in design required to accomplish this task is not readily available with traditional rolled shapes. Thus, the designs rely on advancements in materials and casting technology to create connectors specifically configured for seismic performance. To date, three modular connection configurations have been developed: (1) a semi-rigid modular bolted connector for partially-restrained frames; (2) a superelastic post-tensioned connecting system; and, (3) a cast modular node for moment-resisting frames. Trial designs have been developed for each of the three configurations and an analytical program has been initiated. Alpha prototypes for two of the concepts have been designed. One prototype has been created, and experimental work is underway. Copyright 2004 ASCE.
• Fleischman, R. B., Sumer, A., & Xuejun, L. i. (2004, January). Development of modular connections for steel special moment frames. In Proceedings of the 2004 Structures Congress - Building on the Past: Securing the Future, 821-829.
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  Abstract: Modular connections have been developed for use in seismic-resistant steel moment frames. The connections are configured specifically for optimal seismic response through the use of a steel casting process. The impetus for developing these connections is the recently discovered susceptibility of steel special moment frames during earthquakes. Major features of the modular connections are the minimization of stress/strain and the removal of the field weld from the critical cross-section. To date, two prototypes had been fully developed: (1) a panel zone dissipator modular node (PZ-MN); and (2) a bolted modular connector (MC). The PZ-MN dissipates energy through stable panel zone yielding without column kinking and weld distress; the MC dissipates energy in a variable-arm connector that minimizes plastic strain demand and eliminates prying forces. The prototypes were developed through a comprehensive analytical program using nonlinear finite element (FE) analysis. Full-scale prototypes were cast and tested under the FEMA-350 protocol. These connections exhibited stable energy dissipation and remarkable ductility.
• Fleischman, R. B., & Hoskisson, B. E. (2000, May 8-10).

  Modular Connectors for Seismic Resistant Steel Moment Frames

  . In Proceedings, Structures Congress XVII, American Society of Civil Engineers,.
• Fleischman, R. B., Chasten, C. P., Lu, L., & Driscoll, G. C. (1989, June). Top-and-Seat-Angle connections and End-Plate Connections: Snug vs. Fully Pre-Tensioned Bolts. In National Engineering Conference, American Institute of Steel Construction, 4:1-29.
• Fleischman, R. B., Sause, R., Rhodes, A. B., & Pessiki, S. (1996, January). Seismic behavior of precast parking structure diaphragms. In Structures Congress - Proceedings, 2, 1139-1146.
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  Abstract: Six parking structures collapsed during the 1994 earthquake in Northridge, California. Most of the damaged parking structures employed precast concrete systems in which the floor system is intended to serve as a stiff diaphragm between shear walls. However, large distances between shear walls and the flexibility of joints between precast elements may result in a floor system that is quite flexible. This paper presents a study of the role of the diaphragm deformations in the seismic performance of these structures. Several significant issues regarding the behavior of the parking structures were identified. These include large drift demands on columns due to excessive deformations of the diaphragms; shear wall configurations that cause the diaphragm to twist in plan amplifying these deformations; and cross-sections in critical locations that have insufficient strength to meet the earthquake demands. Possible retrofit concepts are presented.
• Perreira, N. D., Fleischman, R. B., Viscomi, B. V., & Lu, L. (1993, March).

  Automated Construction and ATLSS Connections; Development, Analysis, Experimentation, and Implementation of ATLSS Connections for Automated Construction

  . In Proceedings, AISC National Engineering Conference, pp. 16-1 to 16-20.
• Driscoll, G. C., Heaton, K. A., & Fleischman, R. B. (1991, April).

  Forces In Beam-to-column Connections

  . In Connections in Steel Structures II: Behavior, Strength, and Design, pp. 54 - 60.
• Fleischman, R. B., Viscomi, B. V., & Lu, L. (1991, May).

  ATLSS Connections -- Concept, Development and Experimental Investigation

  . In Proceedings of the Tenth National Structures Congress, pp. 426-430.
• Chasten, C. P., Fleischman, R. B., Driscoll, G. C., & Lu, L. (1989, June).

  Top and Seat Angle Connections and End Plate Connections: Behavior and Strength Under Monotonic and Cyclic Loading

  . In Proceedings, National Engineering Conference,, pp. 6-1-6-32.
• Chasten, C. P., Fleischman, R. B., Lu, L., & Driscoll, G. C. (1987).

  Semi-Rigid Steel Connections and Their Effects on Structural Steel Frames

  . In Connections in Steel StructuresII: Behavior, Strength- and Design.

Presentations

• Fleischman, R. B. (2015, December). Total Project Planning: Case Study 1: PCI Building. NHERI@UCSD Users Training Workshop. University of California - San Diego, La Jolla CA: National Science Foundation (NSF) Natural Hazards Engineering Research Infrastructure (NHERI) Program.
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  “Total Project Planning: Case Study 1: PCI Building”, NHERI@UCSD Users Training Workshop, NSF NHERI Program, UC San Diego, La Jolla CA, Dec. 14-15 2015 (invited speaker)
• Fleischman, R. B. (2014, September). Large Scale Shake Table Testing of Precast Concrete Structures. Workshop on Future Directions for the UC San Diego Large Outdoor Shake Table. La Jolla CA: University of California-San Diego.
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  “Large Scale Shake Table Testing of Precast Concrete Structures”, Workshop on Future Directions for the UC San Diego Large Outdoor Shake Table, UC San Diego, La Jolla CA, Sept. 5 2014 (invited speaker)
• Fleischman, R. B. (2014, September). Sustainable Precast Concrete Construction. 2nd Sino-U.S. Workshop on the Challenges Ahead: Sustainability Issues. Pasadena CA: National Science Foundation.
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  “Sustainable Precast Concrete Construction”, 2nd Sino-U.S. Workshop on the Challenges Ahead: Sustainability Issues, Sept 8-9, 2014, sponsored by the NSF, Pasadena CA (invited speaker)

Poster Presentations

• Fleischman, R. B. (2015, April). A Seismogeodetic Approach to Building Monitoring Using MEMS Accelerometers. SSA Annual Meeting. Pasadena CA: Seismological Society of America.
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  Jessie K. Saunders, Yehuda Bock, Robert Fleischman, Jianghui Geng, Dara E. Goldberg Jennifer S. Haase, Diego Melgar, Arpit Nema, D. Glen Offield, Jose Restrepo, Melinda Squibb , Zhi Zhang (2015). “A Seismogeodetic Approach to Building Monitoring Using MEMS Accelerometers”. Seismological Society of America (SSA) Annual Meeting. Pasadena CA. Technical Poster
• Fleischman, R. B. (2015, November). Deformable Connection For Earthquake-Resistant Building Systems. JAEE 11th Annual Conference and International Symposium on Earthquake Engineering 2015. Tokyo JAPAN: University of Tokyo, Institute of Industrial Science.
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  Georgios Tsampras, Richard Sause, Robert Fleischman, Jose I. Restrepo Dichuan Zhang, Joseph Maffei, David Mar, Deformable Connection For Earthquake-Resistant Building Systems, Poster presented at JAEE 11th Annual Conference and International Symposium on Earthquake Engineering 2015, on Thursday, November 19, 2015, at the University of Tokyo, Institute of Industrial Science.
• Fleischman, R. B. (2014, December). Seismogeodetic Monitoring of Structural Deformation during Shaketable Experiments. AGU Fall Meeting. San Francisco CA: American Geophysical Union.
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  J. Haase, J. Saunders, J. Geng, Y. Bock, D. Goldberg, D. Melgar, J. Restrepo, A. Nema, R. Fleischman, Z. Zhang, D. Offield, M. Squibb (2014). Seismogeodetic Monitoring of Structural Deformation during Shaketable Experiments,. American Geophysical Union (AGU) Fall Meeting, Dec 19-24. San Francisco CA. Technical Poster
• Fleischman, R. B. (2014, March). Shake Table Assessment of GPS and MEMS Accelerometers for Real-Time Seismogeodetic Monitoring of Structural Deformation and Earthquake Early Warning. UNAVCO Annual Meeting. Denver CO: National Science Foundation.
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  Technical Poster: “Shake Table Assessment of GPS and MEMS Accelerometers for Real-Time Seismogeodetic Monitoring of Structural Deformation and Earthquake Early Warning”–Bock Y et al., UNAVCO Annual Meeting, Denver CO March 2014
• Fleischman, R. B. (2014, Aug). REU Posters for NEESR Undergraduate Research Experience (3 posters presented). NEES Quake Summit. Reno NV: National Science Foundation (NSF) Network for Earthquake Engineering Simulation (NEES).
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  REU Poster Presentations (3), NEES Quake Summit, Reno NV Aug 2013 by UA undergrads:Austin HoukMackenzie LostraScott Kuhlman

Others

• Fleischman, R. B., & Sumer, A. (2003, January). Development of modular cast steel connections for seismic-resistant building frames. Standardization News.
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  Abstract: The development of modular cast steel connections for seismic-resistant building frames is discussed. With the freedom of design and robust properties of steel, castings contribute to improve safety and reliability in building construction. The most important quality of the of the casting is ductility, that is the reliability to undergo large plastic deformation without fracture.