Thrust Area I Building Systems
The Building Systems thrust area was created in Year 7 to bring focus to the research and implementation issues that were exposed but not completed in the Van Nuys and UC Science building testbeds. In these testbed assessments of existing buildings, researchers demonstrated the capacity of the PBEE methodology to integrate data from a hazard analysis into a structural analysis, and then to use the engineering demand parameters generated to calculate damage and to assess losses in terms of repair costs, casualties, and downtime. These probabilistic assessments were then presented in a variety of formats for decision makers to engage in design and cost trade-offs.
The testbeds demonstrated the present capacity to complete each step in the process, but they also highlighted areas that need further research and development. The most important needs, which form the goals for the Building Systems thrust area for Years 810, are:
- to improve the capacity to model performance decisions (EDPs to DVs),
- to benchmark the performance of new reinforced concrete building systems, and
- to package the PEER performance-based engineering methodology in a way that makes it accessible to the engineering community. This packaging effort is part of a broader outreach effort that is a major component of the Year 10 plan.
As illustrated in the strategic planning chart of Figure 2.14, the TA I plan for Years 8 through 10 is organized around the three themes of demonstration/benchmarking, loss assessment/decision making, and packaging/outreach. To make informed "Performance Decisions," an engineer as well as an owner or facilities manager must understand the trade-offs involved in design alternatives in terms of up-front construction costs as well as probable repair costs, injuries to occupants, and time needed for recovery from damage. To improve the translation of engineering demand parameters to economic and human consequences, we have three projects focusing on modeling consequences, and estimating losses from the benchmark study (PIs: Comerio , Miranda , and Beck . On benchmarking, Deierlein  is continuing work with input from Lowes  on structural fragilities and damage models of structural components . Stewart  is continuing work on ground motions, site effects, and soil-foundation-structure interaction. His project is complemented by a collaborative effort by Hutchinson and Kutter  on shallow foundation modeling and performance. Cornell  has a related study on characterizing earthquake Intensity Measures (IM) and ground motion scaling procedures. Krawinkler  is responsible for the overall packaging of the methodology for practicing engineers, while May  will focus on the role of performance engineering in the regulatory systems and mechanisms for outreach for early adopters in the engineering community.
In addition to the ongoing projects, the Year 10 plan includes a new initiative  to collaborate with professional organizations and building department officials on a detailed application study utilizing PEER's research methodology to examine the seismic performance of high-rise residential buildings in urban regions. This project was motivated by a need voiced by local and regional building officials in California and strong interest by the engineering community to apply performance-based methods to address the problem. From PEER's perspective, the project is an ideal opportunity to accelerate the implementation and adoption of PBEE by the engineering community.
Critical Mass and Level of Effort
Overall, all TA I researchers will work across the spectrum of the performance equation, but each will contribute to the methodology as well as to specific benchmarking case studies. There is a critical mass in each area of emphasis: characterization of earthquake input motions (Cornell, Stewart), structural analysis and design (Deierlein, Lowes, Krawinkler), foundation performance (Hutchinson, Kutter), and loss assessment, performance decisions, and implementation (Comerio, Miranda, Beck, and May). While each Principal Investigator will be asked to complete specific components of the work, each is expected to coordinate and contribute to the overall thrust area effort.
Below, each Year 9 research project is briefly described.
Comerio  is working on a method to estimate time needed to re-occupy a building based on factors unrelated to the repair of physical damage. These include the importance of the space to operations, the ability to finance, and the ability to secure "surge" space for construction. The methodology is being integrated with casualty and cost estimating, with a specific focus on the translation from engineering demand parameters to loss consequences.
Miranda  has developed a sophisticated method for estimating probable loss costs based on engineering demand parameters. He has applied the model to the benchmarking study and has developed ways to simplify the analytic approach for comparing alternative design concepts. For Years 9 and 10 the objective is to develop a toolbox of procedures and models that will enable practicing structural engineers to conduct loss assessments of buildings. Specific objectives of this research are: (a) development of fragility functions for generic nonstructural components; (b) development of generic loss curves for building stories; and (c) development of tools to facilitate loss estimation calculations and delivering loss information to decision makers. There will be considerable coordination between these "performance decision" researchers and those involved in benchmarking and methodology development. The larger goal is to develop methods that translate engineering outputs into decision parametersissues that force design and performance decisions.
May's project  is focusing on a review of the societal implications of PBEE, taking a systematic look at the benefits of performance engineering, particularly in the regulatory context. May has focused on mechanisms to transfer performance engineering methods to engineering practitioners and the regulatory community. As an example of successful societal adoption of regulatory innovations, May is focusing attention on "green buildings" and the growing movement for adoption of the green building voluntary standards. He is collecting documents and data about the factors that have led states to adopt the voluntary standards for public and other buildings. This serves as a useful case study from which lessons can be drawn for PBEE.
Deierlein  is conducting the lead project in the benchmarking effort. He is applying the PEER methodology and tools to assess the performance of RC buildings that conform to current code standards. He is (a) benchmarking the performance of building code compliant RC frames, (b) contributing to the development and "packaging" of the PBEE methodology and enabling data and technologies through their application to the benchmarking exercise, (c) conducting studies to use PBEE assessment tools to ascertain how building performance is affected by key design criteria for minimum strength, stiffness, and ductility, and (d) evaluating trade-offs, using the PBEE decision metrics, for various systems and configurations.
Beck  is using the structural performance information generated in the benchmark project  to perform loss estimation. In support of this goal he is focusing on the following objectives: (1) coordinate further development of his loss estimation toolbox with Miranda  so that a single packaging of PEER's EDP to DV methodology results, (2) in coordination with Comerio  further develop the PEER methodology for estimation of indirect losses arising from downtime, (3) further develop the PEER methodology for estimating deaths and injuries, and (4) in coordination with May begin developing a decision analysis framework that uses the "3Ds" (dollars, downtime, and deaths) as DVs but also allows the decision maker to account for his/her risk attitude.
Lowes  is developing comprehensive information to support modeling of reinforced concrete beam-column joints (Year 9) and walls (Year 10) for performance-based earthquake engineering. The project scope includes (1) development and posting to a website of information and data from experimental testing of beam-column joint and walls, (2) documentation of response-prediction models developed as part of the PEER research effort, (3) documentation of performance-prediction models developed as part of the PEER research effort, and (4) examples demonstrating the application of response and performance-prediction models.
Stewart's emphasis is the integration of geotechnical/seismological uncertainties into a unified analysis of system performance . The uncertainties that are being considered include epistemic uncertainty in the site hazard, aleatory uncertainty in the variation of ground motion from the free-field to the foundation (i.e., the so-called "kinematic interaction" effect), and aleatory uncertainty in the soil flexibility/damping associated with inertial soil-structure interaction. Stewart [1412005c] also is involved in coordinating and complementing the work done by Hutchinson and Kutter on shallow foundation modeling.
Hutchinson [1412005a] and Kutter [1412005b] are focusing on establishing engineering criteria and guidelines for design and performance assessment of the interface between the superstructure and the supporting soil for shallow foundations. The goal of this joint project is to develop the necessary tools to predict rotations and translations at the soil shallow foundation interface and to allow engineers to assess, through quantitative analysis, the trade off between the benefits (energy dissipation and isolation) and the detriments (e.g., permanent and cyclic settlement and/or tilt) associated with foundation nonlinearity.
Cornell  is in the process of bringing closure to the all-important issues of intensity measure (IM) selection and ground motion scaling. Included are both scalar and vector schemes for IMs. Cornell's objective is to produce comprehensive IM and record selection recommendations for loss estimation and collapse evaluation. This includes (1) completion and packaging of the use of inelastic displacement as an IM, (2) quantification of near-fault effects and of characteristics of near-fault ground motions, and (3) development of selection and scaling procedures to deal with the evaluation of bi-directional effects, i.e., orthogonal directions with very different first-mode periods.
Krawinkler  is taking the lead in facilitating the use of the PEER PBEE methodology in engineering practice. His project is a major step of the building systems packaging/outreach program, whose objective it is to communicate the PEER methodology to the users. He is completing a design decision support system that facilitates the selection of effective structural systems by simultaneously evaluating economic loss and collapse safety considerations. He is developing a set of guidelines for carrying out a performance assessment, summarizing processes and data for simplified approaches for performance assessment, and refining and summarizing data and criteria that can form the basis for performance-based design.
Research Advances and Deliverables
The Building Thrust Area combines researchers from four of the five Years 27 thrust areas Loss Modeling and Decision Making, Geotechnical Performance, Assessment and Design Methodology, and Structural and Nonstructural Performance. The advances made in each thrust area and in the proof-of-concept testbeds shaped the decision to create the Building Thrust Area, which is now in its second year of existence.
In the previous Thrust Area 1, Loss Modeling and Decision Making, the majority of the research focused on three areas: (1) Identification of decision making factors, (2) Gaging losses and costs, and (3) Loss Modeling. Work by several researchers identified what we called the "3Ds"death, dollars, and downtimeas the key decision factors. Metrics were developed for measuring structural, nonstructural, economic, human and institutional losses by Beck, Chang, Comerio, Ince, Maszaros, Miranda, Porter, and Shoaf. The various approaches were applied in the Van Nuys and UC Science Testbeds. These have been published in numerous scholarly articles and documented in the PEER testbed reports. In Years 67 we developed a clear understanding of the economic framework needed for decision making, and basic approaches to estimating casualties and downtime. This work serves as the basis for the goals articulated for Years 810: to refine and simplify the methodology for understanding losses and making performance decisions. In Years 8 and 9 much progress was made in downtime modeling, and the various approaches for loss modeling were unified so that the two basic approaches proposed by Miranda and Beck follow a consistent pattern that varies in details but not in concepts.
In a parallel effort, May focused on the larger policy issues of adoption and implementation. His work up to Year 7 looked at performance standards in a societal context, including the barriers to adoption of performance standards as well as the implications of performance standards on regulatory systems. He has published several articles comparing performance standards in a variety of regulatory models. In Years 810 he is focusing on broader societal benefits derived from performance engineering and mechanisms for outreach to "early adopters." He is using green building as a case study for collecting data about the factors that have led states to adopt the voluntary standards for public and other buildings.
Similarly, in the previous Thrust Areas 2, 3, and 5, geotechnical and structural engineers developed and tested performance models for building systems. Much progress has been made in quantifying structural component response (Moehle, Lehman, Wallace, Robertson), nonstructural components and contents (Miranda, Restrepo, Makris, Hutchinson), soil- foundation-structure interaction effects (Stewart), geotechnical uncertainties and their effects on engineering demand parameters (Kramer), and behavior of shallow foundations (Kutter and Hutchinson). The work on shallow foundation modeling has matured to the degree that two different but complementary models are being implemented in the OpenSees platform. Stewart has developed models to enable site-specific data to be utilized in PSHA, and those models are implemented in OpenSHA.
At the end of Year 6 most basic concepts of a comprehensive performance assessment framework had been put in place. Different methods for uncertainty propagation had been explored and evaluated, ranging from simple first-order second-moment approaches to full Monte Carlo simulation (Beck, Porter, Cornell). Work was performed on quantifying sensitivities and identifying those uncertainties that significantly affect the decision variables on which performance assessment is based (Der Kiureghian, Conte, Krawinkler). In Years 7 and 8, more emphasis began to be placed on performance-based design (Krawinkler) and benchmarking (Deierlein). At the same time, work on insufficiently resolved issues of performance assessment, such as collapse prediction (Krawinkler) and EDP-DM-DV relationships (Beck/Porter, Lowes), was integrated through the Van Nuys testbed study and the ongoing benchmark study (Deierlein, Stewart). The effort on simplified performance assessment and performance-based design (Krawinkler) has led to a semi-graphical design decision support system that facilitates selection of an effective structural system based on quantitative loss and collapse mitigation strategies.
Testing of the performance assessment methodology forms a crucial part of the development effort. During Years 57, the two building testbeds (the UC Sciences Building and the Van Nuys Building) were the center of focused studies in which the PBEE assessment methodology was tested, additional research needs identified, simplified approaches developed, and the socio- economic impact of different performance objective formulations demonstrated. The second "testing" effort took shape in Year 8 and is expected to continue until Year 10. It is concerned with benchmarking and packaging the PEER PBEE methodology for buildings. This effort ties in with the needs of the community (e.g., ATC 58, ATC 63, ASCE 7) to carry out an assessment of the performance of buildings designed according to present code requirements. In this work the PBEE methodology is applied to selected subsets of reinforced concrete frame and wall buildings in order to assess current code design procedures and find out how the methodology has to be packaged in order to be useful to the engineering profession.
In Year 10, the Building Systems Thrust Area will bring to a closure the work started in Years 8 and 9. This will include (1) a clear presentation of the PEER performance methodology through the benchmarking studies, (2) completion of the methodology for performance decisions in the translation of engineering demand parameters to decision variables, (3) simplified design decision tools for practitioners, (4) continued investigations of policy and implementation hurdles, and (5) outreach strategies to enhance the adoption of performance-based engineering. The primary emphasis in Year 10 will be on refinement, implementation, and packaging of the PEER PBEE methodology and on communicating the methodology to the users and stakeholders. From a more global perspective, the emphasis will be on outreach activities to professional groups and on illustrations of the methodology.
The only newly proposed project for Year 10 is one to involve researchers and practicing engineers in an application study to apply PBEE to help establish appropriate design criteria and procedures for high-rise residential buildings. This project will respond to an important practical need among engineers and building officials in regions of high seismicity. At the same time, we envision that it will further inform the ongoing research efforts and facilitate the implementation and adoption of PBEE methods in engineering practice. Detailed planning for the project, including negotiations for external matching funds to support ground motion modeling, workshops, and design guidelines, is presently under way.
- Altoontash, A., Cordova, P., Deierlein, G. G. 2006. Implementation and validation of cumulative damage models for structural performance assessment. Proc. 8th National Conference on Earthquake Engineering, Paper ID 1540. 10 pgs. EERI.
- Baker J.W. and Cornell C. A. 2005. A vector-valued ground motion intensity measure consisting of spectral acceleration and epsilon. Earthq. Engrg. & Structural Dyn. 34(10): 11931217.
- Baker J.W. and Cornell C.A., 2006. Correlation of response spectral values for multi-component ground motions, Bull. Seism. Society Am. 96(1): 215257.
- Baker J.W. and Cornell C.A., 2004. Choice of a vector of ground motion intensity measures for seismic demand hazard analysis. Proc. 13th World Conference on Earthquake Engineering, Vancouver, Canada, 15 pp.
- Baker J. W., Cornell C. A., and Tothong P. 2005. Disaggregation of seismic drift hazard. 9th Intl. Conference on Struct. Safety and Reliability (ICOSSAR05), Rome, Italy, 7 pp.
- Beck, J.,Goulet, C., Haselton, C., Mitrani-Reiser, J., Stewart, J., Taciroglu, E., Deierlein, G. April 2006. Evaluation of the seismic performance of a code-conforming reinforced-concrete frame building - Part I: Ground motion selection and structural collapse simulation, Proc. 8th National Conference on Earthquake Engineering, San Francisco, CA. Paper No. 1576 EERI.
- Beck, J., Mitrani-Reiser, J., Haselton, C., Goulet, C., Porter, K., Deierlein, G. April 2006. Evaluation of the seismic performance of a code-conforming reinforced-concrete frame building Part II: loss estimation. Proc. 8th National Conference on Earthquake Engineering, San Francisco, CA. / Paper No. 969. EERI.
- Choi, Y., Stewart, J. P., and Graves, R.W. 2005. Empirical model for basin effects that accounts for basin depth and source location. Bull. Seism. Soc. Am., 95(4): 141227.
- Choi, Y., and Stewart, J. P. 2005. Nonlinear site amplification as function of 30 m shear wave velocity. Earthq. Spectra 21(1): 130.
- Comerio, M. Estimating downtime in loss modeling. 2006. Earthq. Spectra 22(2) (May).
- Comerio, M. Downtime modeling for risk management. June 2005. Safety and Reliability of Engineering Systems and Structures, G. Augusti, G.I. Schueller, M. Ciampoli (eds.) ICOSSAR. Rome.
- Deierlein, G. G., Haselton, C. 2005. Developing consensus on provisions to evaluate collapse of reinforced concrete buildings. Proc. First NEES/E-Defense Workshop on Collapse Simulation of Reinforced Concrete Building Structure. PEER Report 2005/10, pp. 319.
- Deierlein, G. G., Haselton, C. 2005. Benchmarking seismic performance of reinforced concrete frame buildings. Proceedings of 2005 ASCE-SEI Structures Congress. 12 pgs. ASCE. Harden, C. W. 2003. Numerical modeling of the nonlinear rocking response of shallow foundations. M.S. Thesis, University of California, Irvine.
- Haselton, C., Goulet, C., Mitrani-Reiser, J., Stewart, J. P., Taciroglu, E., Deierlein, G. G. 2006. Evaluation of the seismic performance of a code-conforming reinforced-concrete frame building Part 1: Ground motion selection and structural collapse simulation. Proc. 8th National Conference on Earthquake Engineering. Paper ID 1576. 10 pgs. EERI.
- Haselton, C., Baker, J. 2006. Ground motion intensity measures for collapse capacity prediction: choice of optimal spectral period and effect of spectral shape. Proc. 8th National Conference on Earthquake Engineering. Paper ID 461. 10 pgs. EERI.
- Haselton, C. B., Deierlein, G. G. 2006. Toward the codification of modeling provisions for simulating structural collapse. Proc. 8th National Conference on Earthquake Engineering. Paper ID 1348. 10 pgs. EERI.
- Haselton C., and Baker J. W. 2006. Ground motion intensity measures for collapse capacity prediction: Choice of optimal spectral period and effect of spectral shape. Proc. 8th National Conference on Earthquake Engineering, San Francisco, California, 10 pp.
- Ibarra, L. F., Medina, R. A., and Krawinkler, H. Hysteretic models that incorporate strength and stiffness deterioration. Intl. J. Earthq. Engrg.& Struct. Dyn. 34(12): 14891511.
- Ibarra, L., and Krawinkler, H. 2005. Effect of uncertainty in system deterioration parameters on the variance of collapse capacity. Proc. ICOSSAR'05, Rome, Italy, June 2024, 2005. pp. 3583-3590 [Millpress, Rotterdam, ISBN 90 5966 040 4].
- Krawinkler, H., Zareian, F., Medina, R., Ibarra, L., 2006. Decision support for conceptual performance-based design. Earthq. Engrg. & Struct. Dyn. 35(1): 11533.
- Krawinkler, H. 2006. Importance of good nonlinear analysis. 2006. Proc. 2006 Annual Meeting of the Los Angeles Tall Buildings Structural Design Council, Los Angeles, May 5, 2006.
- Krawinkler, H. 2006. Performance assessment of an old RC building A PEER testbed study. Proc. 8th National Conference on Earthquake Engineering, San Francisco, California, April, 2006. Paper 1845. Earthquake Engineering Research Institute.
- Liel, A. B., Haselton, C. B., Deierlein, G. G. 2006. How have changes in building code provisions for reinforced concrete frame structures improved seismic safety. Proc. 8th National Conference on Earthquake Engineering. Paper ID 451. 10 pgs. EERI.
- Lowes, L. 2004. Modeling the response of RC Beam-column joints. 2004. 13th World Conference on Earthquake Engineering. 16 August 2004 Vancouver, B.C. Canada. 2004. Paper 1001.
- May, P. Prospects for performance based earthquake engineering. 2006. Paper presented at the 8th National Conference on Earthquake Engineering, San Francisco, April 1720, 2006 1. April 2006. Earthquake Engineering Research Institute.
- May, P. Regulatory regimes and accountability.2005. Paper presented at the Law and Society Association Annual Meeting, Las Vegas, June 25, 2005 2. June 2005. Law and Society Assn.
- May, P. Performance-based regulation and regulatory regimes. Paper presented at the 13th World Conference on Earthquake Engineering, Vancouver BC, August 16, 2004 3. August 2004. International Earthquake Engineering Association.
- Medina, R.A., and Krawinkler, H. Evaluation of drift demands for the seismic performance assessment of frames. J. Struct. Engrg. 131(7): 10031013. ASCE.
- Medina, R. A., and Krawinkler, H. Strength demand issues relevant for the seismic design of moment-resisting frames. Earthq. Spectra 21(2): 41540.
- Mitrani-Reiser, J., Haselton, C., Goulet, C., Porter, K., Beck, J., Deierlein, G. G. 2006. Evaluation of the seismic performance of a code-conforming reinforced-concrete frame building Part II: Loss estimation. Proc. 8th National Conference on Earthquake Engineering. EERI, Paper ID 968. 10 pgs.
- Stewart, J. P., Choi, Y., and Graves, R. W. 2005. Uncertainty of southern California basin depth parameters. Bull. Seism. Soc. Am. 95(5), 198893.
- Stewart, J. P., Goulet, C., Bazzurro, P., and Claassen, R. 2006. Implementation of 1D ground response analysis in probabilistic assessments of ground shaking potential. In GeoCongress 2006 Geotechnical Engineering in the Information Technology Age. D.J. DeGroot, J.T. DeJong, J. D. Frost, and L. G. Baise (eds.), Atlanta, GA, Feb. 26 March 1, 6 pages (electronic file).
- Tothong, P., and Cornell, C. A. 2006. Application of Nonlinear static analyses to PSDA. Proc. 8th National Conference on Earthquake Engineering, San Francisco, California, 10 pp.
- Zareian, F., and Krawinkler, H. 2006. Simplified performance-based earthquake engineering, Paper 1083, Proc. 8th National Conference on Earthquake Engineering, Earthquake Engineering Research Institute, San Francisco, California. April 2006.
- Zareian, F., Krawinkler, H., and Ibarra, L. F. 2006. Why and how to predict the probability of collapse of buildings. Proc. 8th National Conference on Earthquake Engineering, San Francisco, California. Paper 1579. April, 2006. Earthquake Engineering Research Institute.
- Zareian, F., Krawinkler, H. 2005. A Simple procedure for performance-based design. Proc. 74th SEAOC Annual Convention, San Diego, California.
For additional details, see the PEER Annual Report - Volume 2 (PDF file - 7.6 MB).