Column shear-axial failure in existing vulnerable reinforced concrete (RC) frame buildings constructed before the mid 1970's is a major seismic risk. The challenges associated with spatial response and system load redistribution capability at the ons... [more]

Column shear-axial failure in existing vulnerable reinforced concrete (RC) frame buildings constructed before the mid 1970's is a major seismic risk. The challenges associated with spatial response and system load redistribution capability at the onset of collapse has not been resolved yet. The acceptance criteria in current seismic rehabilitation provisions are defined at the element level with no due consideration for the system robustness. Four sets of three-dimensional, geographically distributed hybrid simulations (HS) will be conducted using the George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) facility at the University of Illinois at Urbana-Champaign to obtain the response up to collapse of a representative three-dimensional structural system subjected to one-directional and tri-axial seismic ground motions. This research will investigate, characterize, model, and derive practical procedures for the consequences of column shear-axial failure on the collapse of existing vulnerable RC structures. The project will develop system-level acceptance criteria and analytical tools for near collapse seismic performance of existing non-ductile RC frame structures. Data from this project will be archived and made available to the public through the NEES Project Warehouse/data repository at http://www.nees.org. This project is a collaborative effort between researchers from Northeastern University and Western Michigan University. This project utilizes the unique HS capability provided by the NEES facility to simulate near collapse response of existing vulnerable RC buildings through the integration of large scale physical experiments and numerical models. If successful, this research project will shift the philosophy of structural assessment of vulnerable buildings from component-level to system-level evaluation. The application of system-level evaluation methods developed in this project can lead to more efficient and cost-effective rehabilitation methods for existing non-ductile RC buildings against collapse by identifying and prioritizing buildings susceptible to partial/total collapse. Thus, optimal use of limited resources can be made. A multi-level education and outreach program will provide students from K-12, college, and underrepresented groups, as well as high school physics teachers, with the opportunity to participate in project activities. This will include development of three teaching modules suitable for elementary, middle, and high school students covering the basics of earthquake engineering and topics relevant to collapse analysis. This award is part of the National Earthquake Hazards Reduction Program (NEHRP). [less]

Solid reinforced concrete structural walls that span from the foundation to the building roof are one of the most common structural systems used to resist earthquake forces in the United States and worldwide. In many buildings, these walls surround s... [more]

Solid reinforced concrete structural walls that span from the foundation to the building roof are one of the most common structural systems used to resist earthquake forces in the United States and worldwide. In many buildings, these walls surround stairs and elevators or are located at the building perimeter. Evolution in wall design and construction practices has resulted in thinner, more efficient wall geometries that are pushing the seismic performance limits of this structural system. Indeed, poor performance in some recent earthquakes and structural engineering laboratory tests demonstrate that revisions in seismic design practices now are necessary to ensure that future construction meets the high performance expectations for modern construction. This research will explore seismic design and performance limits for structural walls, considering both conventional and innovative wall construction practices. The research will investigate: (a) mechanics models to understand poor performance of conventional construction, (b) innovative yet practical new systems that can transform design practices, (c) performance-based design limits for conventional and innovative systems, and (d) international collaborative development and interpretation of shake table tests of full-scale, three-dimensional building structures. This research is a collaborative effort among researchers at the University of California at Los Angeles and University of California at Berkeley. Primary tests will be conducted at the George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) facilities at the University of California at Berkeley and University of Illinois at Urbana-Champaign. In addition, the project team will collaborate with researchers from the University of Tokyo and Japan's National Research Institute for Earth Science and Disaster Prevention, who will conduct full-scale building tests on the E-Defense shake table facility in Miki, Japan. Data from this project will be archived and made available to the public through the NEES Project Warehouse/data repository (http://www.nees.org). The research program tackles an important and challenging problem that will advance discovery and understanding of one of the most common building systems used to resist earthquake forces. The results of the research will be disseminated in multiple ways: by sharing results using NEES resources, by involving earthquake professionals, and by disseminating educational materials. The results will benefit society most directly by helping define appropriate seismic design requirements for efficient and high-performance building construction. These goals will be accomplished by the active participation of the researchers with professional organizations and by utilizing an advisory board of expert engineering professionals actively involved in earthquake engineering. Graduate and undergraduate student experiences will be enhanced by active participation in research and by collaboration among the participating universities, with Japanese researchers, and interactions with design professionals. This award is part of the National Earthquake Hazards Reduction Program (NEHRP). [less]

This award is an outcome of the NSF 08-519 program solicitation, "George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research (NEESR)" competition and includes the University of Washington (lead institution), University of Minn... [more]

This award is an outcome of the NSF 08-519 program solicitation, "George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research (NEESR)" competition and includes the University of Washington (lead institution), University of Minnesota (subaward), and University at Buffalo, SUNY (subaward). This project will utilize the NEES equipment sites at the University of Minnesota and University at Buffalo and has strong international collaboration with large-scale experiments to be performed at the National Center for Research in Earthquake Engineering (NCREE) in Taiwan. The goal of this project is to develop a smart and resilient steel plate shear wall (SR-SPSW) system with the potential to transform seismic design in areas of moderate and high seismicity. The system strategically combines the benefits of self-centering and steel plate shear wall technologies to create a robust, ductile, and easily repairable system that will reduce life-cycle costs for buildings. Most traditional seismic load resisting systems will suffer structural damage during seismic events; the cost and downtime associated with repair of that damage has led to staggering economic losses. The proposed SR-SPSW system could drastically reduce those losses. SPSWs are excellent candidates for the application of self-centering technology; they have high strength and elastic stiffness and require low re-centering forces. The buckling and yielding behavior of the web plate will also be leveraged to develop self-sensing concepts such that post-event decisions regarding web plate replacement can be made with minimal disruption. SPSW behavior under earthquake loading is highly nonlinear, and complex component interactions exist; of particular complexity are the interactions between the web plate tension field action and the forces in the re-centering mechanisms of the proposed SR-SPSWs. Large-scale testing using advanced experimental techniques and instrumentation will generate data to be used to develop numerical models anchored in physical behavior. Application of those tools in parametric analyses of SPSW systems will provide a new level of understanding of the system response and help to eliminate overly conservative design processes. To ensure that the new SR-SPSW system will be implemented, and to increase the use of conventional SPSW systems, this research will also seek to fill critical knowledge gaps in SPSW system behavior including the understanding of coupled SPSW behavior and the expected distribution of yielding in multistory SPSW. The project also includes a series of activities that will advance the NEES education, outreach, and training goals. Through collaboration with Seattle-MESA, the project will engage high school students from underrepresented minorities in structural engineering and laboratory experimentation, ultimately helping to promote diversity in engineering and science. The project team also includes faculty and undergraduates from Seattle University, a predominantly undergraduate institution, who will contribute to the research endeavor. The project will excite K-5 students about science and engineering through the development of the Wicked Walls program; a hands on learning activity showing students the benefits of walls for seismic resistance. Finally, outreach to practicing structural engineers will occur through the Seismic Provisions committee, conference presentations, and seminars with the cooperation of AISC. The research team experience in developing national and international codes ensures that research outcomes will have an immediate impact on design practice. Data from this project will be made available through the NEES data repository (http://www.nees.org). [less]

This award is an outcome of the NSF 09-524 program solicitation "George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research (NEESR)" competition and includes the University of Illinois at Urbana-Champaign (lead institution) an... [more]

This award is an outcome of the NSF 09-524 program solicitation "George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research (NEESR)" competition and includes the University of Illinois at Urbana-Champaign (lead institution) and the University of Hawaii at Manoa (subaward) and Ryan-Biggs Associates of Troy, New York (subaward). This project will utilize the NEES equipment site at the University of Illinois at Urbana-Champaign. The research will enable a new technology for earthquake resistant design of buildings, known as hybrid masonry. This innovative concept for improved seismic performance of low to mid-rise buildings located in all earthquake prone areas, including California, relies on the structural action of special reinforced concrete masonry panels that are attached to a conventional steel frame. Interactions with the surrounding steel frame, and novel steel link connectors that can be designed to act as fuses in dissipating seismic energy, make this a promising engineered system for enhancing seismic performance at a reduced cost and impact on the environment. Research will combine large-scale testing with state of the art computational simulation to identify and discover the seismic performance of this new system. Large-scale, two-story hybrid masonry frames will be constructed and tested at the NEES equipment site at Illinois. A complementary set of steel link connector tests will be done at the University of Hawaii. Practitioner interaction is embedded into the research plan through a partnership with Ryan-Biggs Associates, who are currently designing buildings with this new technology and leading seminars to teach other engineers about this innovative system. A well defined technology transfer program with industry partnership will transform research results to earthquake engineering practice so that building owners may benefit from this research. The intellectual merit of the research will include advancements in discovery and understanding of how buildings constructed with hybrid masonry respond to earthquake motions of varying intensities as well as other lateral loadings such as strong winds or blast. The research will advance the art in structural testing since the scale and complexity of the proposed tests will set a new norm for structural masonry research. In addition, the simulation study will set a new mark in modeling mechanics of masonry and its contact with a frame under seismic loadings. With respect to broader impacts, this research will provide building developers and contractors with an economical alternative for building construction applicable to all seismic zones. It will enhance the national economy since building construction will be less expensive, and following earthquakes of the future, less damage, loss of life or business interruptions will occur. The research will also have an impact internationally as this novel new technology is transferred across borders. Moreover, this research will promote teaching of future generations of structural engineers to become more adept at engineering of such structural systems, and broaden participation of underrepresented groups in engineering by engaging them in this research field. Data from this project will be archived and made available to the public through the NEES data repository. [less]

The proposed research seeks to advance the understanding of, and simulation tools for, the seismic performance of slender walls through experimental and analytical investigations of wall systems with 1) configurations used in modern design, 2) load d... [more]

The proposed research seeks to advance the understanding of, and simulation tools for, the seismic performance of slender walls through experimental and analytical investigations of wall systems with 1) configurations used in modern design, 2) load distributions that are representative of earthquake loading, 3) and consideration of soil-structure-interaction effects. The advanced experimental capabilities of the UIUC MUST-SIM NEES facility will be used to enable realistic simulation of these complex conditions. Instrumentation developed as part of the MUST-SIM facility makes possible high-resolution monitoring of test specimen displacement fields and such data are necessary to enable the proposed model development effort. These data will be used to advance the state-of-the-art for simulation of reinforced concrete structures through the development of fiber-shell elements that can be used to simulate the inelastic response, including localized damage mechanisms, of three-dimensional walls. Results of the proposed experimental investigation and parametric studies using the high-resolution numerical models will be used to advance the state-of-the-practice for design of wall systems including the development of elastic and simplified inelastic modeling techniques that are appropriate for use with commercial software. Additionally, experimental and simulation data will be used to develop performance-based design tools that account for modeling uncertainty and link engineering demand parameters and damage states. [less]

This award is an outcome of the NSF 09-524 program solicitation "George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research (NEESR)" competition and includes the University of Illinois at Urbana-Champaign (lead institution) an... [more]

This award is an outcome of the NSF 09-524 program solicitation "George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research (NEESR)" competition and includes the University of Illinois at Urbana-Champaign (lead institution) and the University of Hawaii at Manoa (subaward) and Ryan-Biggs Associates of Troy, New York (subaward). This project will utilize the NEES equipment site at the University of Illinois at Urbana-Champaign. The research will enable a new technology for earthquake resistant design of buildings, known as hybrid masonry. This innovative concept for improved seismic performance of low to mid-rise buildings located in all earthquake prone areas, including California, relies on the structural action of special reinforced concrete masonry panels that are attached to a conventional steel frame. Interactions with the surrounding steel frame, and novel steel link connectors that can be designed to act as fuses in dissipating seismic energy, make this a promising engineered system for enhancing seismic performance at a reduced cost and impact on the environment. Research will combine large-scale testing with state of the art computational simulation to identify and discover the seismic performance of this new system. Large-scale, two-story hybrid masonry frames will be constructed and tested at the NEES equipment site at Illinois. A complementary set of steel link connector tests will be done at the University of Hawaii. Practitioner interaction is embedded into the research plan through a partnership with Ryan-Biggs Associates, who are currently designing buildings with this new technology and leading seminars to teach other engineers about this innovative system. A well defined technology transfer program with industry partnership will transform research results to earthquake engineering practice so that building owners may benefit from this research. The intellectual merit of the research will include advancements in discovery and understanding of how buildings constructed with hybrid masonry respond to earthquake motions of varying intensities as well as other lateral loadings such as strong winds or blast. The research will advance the art in structural testing since the scale and complexity of the proposed tests will set a new norm for structural masonry research. In addition, the simulation study will set a new mark in modeling mechanics of masonry and its contact with a frame under seismic loadings. With respect to broader impacts, this research will provide building developers and contractors with an economical alternative for building construction applicable to all seismic zones. It will enhance the national economy since building construction will be less expensive, and following earthquakes of the future, less damage, loss of life or business interruptions will occur. The research will also have an impact internationally as this novel new technology is transferred across borders. Moreover, this research will promote teaching of future generations of structural engineers to become more adept at engineering of such structural systems, and broaden participation of underrepresented groups in engineering by engaging them in this research field. Data from this project will be archived and made available to the public through the NEES data repository. [less]

The proposed research seeks to advance the understanding of, and simulation tools for, the seismic performance of slender walls through experimental and analytical investigations of wall systems with 1) configurations used in modern design, 2) load d... [more]

The proposed research seeks to advance the understanding of, and simulation tools for, the seismic performance of slender walls through experimental and analytical investigations of wall systems with 1) configurations used in modern design, 2) load distributions that are representative of earthquake loading, 3) and consideration of soil-structure-interaction effects. The advanced experimental capabilities of the UIUC MUST-SIM NEES facility will be used to enable realistic simulation of these complex conditions. Instrumentation developed as part of the MUST-SIM facility makes possible high-resolution monitoring of test specimen displacement fields and such data are necessary to enable the proposed model development effort. These data will be used to advance the state-of-the-art for simulation of reinforced concrete structures through the development of fiber-shell elements that can be used to simulate the inelastic response, including localized damage mechanisms, of three-dimensional walls. Results of the proposed experimental investigation and parametric studies using the high-resolution numerical models will be used to advance the state-of-the-practice for design of wall systems including the development of elastic and simplified inelastic modeling techniques that are appropriate for use with commercial software. Additionally, experimental and simulation data will be used to develop performance-based design tools that account for modeling uncertainty and link engineering demand parameters and damage states. [less]

Headed anchors/studs are commonly used in structures to connect steel members (e.g., columns, girders, or braces) and concrete elements (e.g., foundations, walls, or columns, respectively). The concrete elements may experience substantial damage (e.g... [more]

Headed anchors/studs are commonly used in structures to connect steel members (e.g., columns, girders, or braces) and concrete elements (e.g., foundations, walls, or columns, respectively). The concrete elements may experience substantial damage (e.g., large cracking) during an earthquake. Understanding the behavior of anchors in cracked concrete is a prerequisite to ensuring satisfactory seismic performance and safety of structures. Current seismic design guidelines, represented by Appendix D of the American Concrete Institute 318-05 document, are not adequate for the design of headed anchors/studs in significantly cracked concrete. The design provisions tacitly rely on reserved capacity of anchors and perceived ductile failure modes due to steel fracture. Both of these rationales are questionable because of the limited data for anchor behavior under seismic loading. In addition, the interaction equations for anchors under combined cyclic tension-shear have not been verified experimentally. As a result, many anchor connections, including those taking advantage of additional reinforcement around the anchors, are often implemented in practice without supporting experimental data. The knowledge gap is due partly to the limited experimental equipment available for such testing before the NEES facilities became operational in 2004. This project will investigate the fundamental behavior of headed anchors/studs under simulated seismic loading and verify and improve the anchor connection details commonly seen in practice. The project will develop connection interface models to improve model-based simulations and to assist in the development of performance-based engineering methodologies. Particularly, this research clarifies the current capacity design philosophy, redefines the definition of ductile failure modes, and evaluates the interaction equation for anchors under cyclic tension-shear. The research also explores extending the existing design equations to anchors embedded in concrete members that may experience significant damage. With the fundamental knowledge on single anchor behavior under seismic load, two typical anchor connections, which have been used in practice without justification, will be evaluated experimentally, and connection details with improved performance characteristics will be developed and verified. Recommendations for effective use of supplemental reinforcement for improving the capacity and ductility of anchor connections will be made, and design guidelines, along with examples, will be generated for engineers [less]

Bridge columns are subjected to combinations of actions and deformations, caused by spatially-complex earthquake ground motions, features of structural configurations and the interaction between input and response characteristics. Combined actions/lo... [more]

Bridge columns are subjected to combinations of actions and deformations, caused by spatially-complex earthquake ground motions, features of structural configurations and the interaction between input and response characteristics. Combined actions/loadings can have significant effects on the force and deformation capacity of reinforced concrete columns, resulting in unexpected large deformations and extensive damage that in turn influences the performance of bridges as vital components of transportation systems. These effects should be considered in earthquake analysis and design of bridges so that significant earthquake damage and severe disruption of transportation systems can be reduced. The objectives of the project are to develop a fundamental knowledge of the impact of combined actions on column performance and system response and to establish analysis and design procedures that include the impact at both the component and system levels. The objectives will be realized by integrating analytical and experimental research where physical tests are driven by analyses and simulations that examine the system response of various bridge types under different loading conditions. The analytical models are calibrated by experimental data and then extended to system response. The experimental program includes quasi-static testing of twenty-four large columns (fourteen will be funded by NEES) providing fundamental behavior including the impact of torsional moments at University of Missouri, Rolla (UMR), pseudo-dynamic testing of three large and four small scale columns with variable axial load, within a bridge system simulation, at the University of Illinois at Urbana-Champaign (UIUC), real-time dynamic testing of eight large scale columns with bidirectional, torsional and variable axial load inputs at University of Nevada, Reno (UNR), four tests provided by the University of Mexico (UNAM), plus an integrated experiment with three columns linked through simulation, conducted at UIUC by UMR. Fragility analysis will be undertaken, leading to the derivation of probabilistically-based fragility relationships for bridges subjected to combined action. Simplified analysis and design tools will be developed as well as the necessary code language to change the existing practice. Design and analysis methods will be derived that will affect the earthquake design practice in the US and internationally. Coordination of an integrated test program has already begun between the US and Japanese researchers. Analysis components will be done at UCLA, UIUC, UMR and UNR. An integrated education, training and outreach program, lead by Washington University, will span from 4th graders to practicing engineers. Modules will be developed for teachers and professors that can be inserted in their courses. Modules will be used by the research team in summer camps, visits to local elementary, middle and high schools, undergraduate and graduate courses and in continuing education courses. Specific programs are targeted towards underrepresented groups. To achieve its objectives, the project will utilize the NEESit cyber-infrastructure, state-of-the-art instrumentation and high-speed data acquisition systems, the NEES equipment sites at UNR and UIUC and the non-NEES site at UMR, which has committed to joining NEESgrid. [less]

The proposed research seeks to advance the understanding of, and simulation tools for, the seismic performance of slender walls through experimental and analytical investigations of wall systems with 1) configurations used in modern design, 2) load d... [more]

The proposed research seeks to advance the understanding of, and simulation tools for, the seismic performance of slender walls through experimental and analytical investigations of wall systems with 1) configurations used in modern design, 2) load distributions that are representative of earthquake loading, 3) and consideration of soil-structure-interaction effects. The advanced experimental capabilities of the UIUC MUST-SIM NEES facility will be used to enable realistic simulation of these complex conditions. Instrumentation developed as part of the MUST-SIM facility makes possible high-resolution monitoring of test specimen displacement fields and such data are necessary to enable the proposed model development effort. These data will be used to advance the state-of-the-art for simulation of reinforced concrete structures through the development of fiber-shell elements that can be used to simulate the inelastic response, including localized damage mechanisms, of three-dimensional walls. Results of the proposed experimental investigation and parametric studies using the high-resolution numerical models will be used to advance the state-of-the-practice for design of wall systems including the development of elastic and simplified inelastic modeling techniques that are appropriate for use with commercial software. Additionally, experimental and simulation data will be used to develop performance-based design tools that account for modeling uncertainty and link engineering demand parameters and damage states. [less]

The proposed research aims to develop a new structural system that employs rocking action and replaceable structural fuses to provide safe and cost effective resistance to earthquakes. The system combines desirable aspects of conventional steel-brac... [more]

The proposed research aims to develop a new structural system that employs rocking action and replaceable structural fuses to provide safe and cost effective resistance to earthquakes. The system combines desirable aspects of conventional steel-braced framing with two alternative and complementary fuse concepts ⿿ shear panel fuses and axial column fuses. The fuses utilize novel materials and components, including combinations of high-performance fiber reinforced cementitious composite shear panels fuses, low-yield steel shear panel fuses, and buckling-restrained axial column fuses. Guided by performance-based capacity design principles, the fuses are easily replaceable and can be tuned to provide optimal performance. Through a combined program of computational and experi¬mental research, the project will encompass component and complete system response and synthesis of the results through a methodology for performance-based design that directly assesses life safety and life-cycle economic factors. The proposed concept emphasizes damage prevention to foundations and other structural elements that are difficult to repair; inelastic energy dissipation in structural fuses that are easy to replace; story drift control so that nonstructural damage is reduced; and sufficient safety against collapse. The research will involve quasi-static testing of a large-scale frame subassembly at the NEES facility at the University of Illinois and dynamic testing of a large-scale frame at the E-Defense shaking table in Japan. [less]

Design: Boundary elements have a longitudinal reinforcement ratio of 3.5% and tranverse reinforcement ratios of 1.0% (38% greater than required) in the in-plane direction and 0.92% (22% greater than required) in the out-of-plane direction. Wall web r... [more]

Design: Boundary elements have a longitudinal reinforcement ratio of 3.5% and tranverse reinforcement ratios of 1.0% (38% greater than required) in the in-plane direction and 0.92% (22% greater than required) in the out-of-plane direction. Wall web reinforcement ratios are is 0.27% in both the horizontal and vertical directions. This is approximately equal to the code-requirement minimum.Loading: a moment-shear ratio based on the ASCE-7 load distribution will be applied. This results in a design base shear of 2.5Agfc^.5, which is 60% of the ACI 318-05 specified capacity (i.e., a phi-factor of 0.6 was used in design). Note that application of the ASCE-7 load distribution requires applicaiton of moment and shear at the top of the wall as well as shear loads at the second and third floors. [less]

The proposed research aims to develop a new structural system that employs rocking action and replaceable structural fuses to provide safe and cost effective resistance to earthquakes. The system combines desirable aspects of conventional steel-brac... [more]

The proposed research aims to develop a new structural system that employs rocking action and replaceable structural fuses to provide safe and cost effective resistance to earthquakes. The system combines desirable aspects of conventional steel-braced framing with two alternative and complementary fuse concepts ⿿ shear panel fuses and axial column fuses. The fuses utilize novel materials and components, including combinations of high-performance fiber reinforced cementitious composite shear panels fuses, low-yield steel shear panel fuses, and buckling-restrained axial column fuses. Guided by performance-based capacity design principles, the fuses are easily replaceable and can be tuned to provide optimal performance. Through a combined program of computational and experi¬mental research, the project will encompass component and complete system response and synthesis of the results through a methodology for performance-based design that directly assesses life safety and life-cycle economic factors. The proposed concept emphasizes damage prevention to foundations and other structural elements that are difficult to repair; inelastic energy dissipation in structural fuses that are easy to replace; story drift control so that nonstructural damage is reduced; and sufficient safety against collapse. The research will involve quasi-static testing of a large-scale frame subassembly at the NEES facility at the University of Illinois and dynamic testing of a large-scale frame at the E-Defense shaking table in Japan. [less]

Design: Boundary elements have a longitudinal reinforcement ratio of 3.5% and tranverse reinforcement ratios of 1.0% (38% greater than required) in the in-plane direction and 0.92% (22% greater than required) in the out-of-plane direction. Wall web r... [more]

Design: Boundary elements have a longitudinal reinforcement ratio of 3.5% and tranverse reinforcement ratios of 1.0% (38% greater than required) in the in-plane direction and 0.92% (22% greater than required) in the out-of-plane direction. Wall web reinforcement ratios are is 0.27% in both the horizontal and vertical directions. This is approximately equal to the code-requirement minimum.Loading: a moment-shear ratio based on the ASCE-7 load distribution will be applied. This results in a design base shear of 2.5Agfc^.5, which is 60% of the ACI 318-05 specified capacity (i.e., a phi-factor of 0.6 was used in design). Note that application of the ASCE-7 load distribution requires applicaiton of moment and shear at the top of the wall as well as shear loads at the second and third floors. [less]

Design: Boundary elements have a longitudinal reinforcement ratio of 3.5% and tranverse reinforcement ratios of 1.0% (38% greater than required) in the in-plane direction and 0.92% (22% greater than required) in the out-of-plane direction. Wall web r... [more]

Design: Boundary elements have a longitudinal reinforcement ratio of 3.5% and tranverse reinforcement ratios of 1.0% (38% greater than required) in the in-plane direction and 0.92% (22% greater than required) in the out-of-plane direction. Wall web reinforcement ratios are is 0.27% in both the horizontal and vertical directions. This is approximately equal to the code-requirement minimum.Loading: a moment-shear ratio based on the ASCE-7 load distribution will be applied. This results in a design base shear of 2.5Agfc^.5, which is 60% of the ACI 318-05 specified capacity (i.e., a phi-factor of 0.6 was used in design). Note that application of the ASCE-7 load distribution requires applicaiton of moment and shear at the top of the wall as well as shear loads at the second and third floors. [less]

Design: Boundary elements have a longitudinal reinforcement ratio of 3.5% and tranverse reinforcement ratios of 1.0% (38% greater than required) in the in-plane direction and 0.92% (22% greater than required) in the out-of-plane direction. Wall web r... [more]

Design: Boundary elements have a longitudinal reinforcement ratio of 3.5% and tranverse reinforcement ratios of 1.0% (38% greater than required) in the in-plane direction and 0.92% (22% greater than required) in the out-of-plane direction. Wall web reinforcement ratios are is 0.27% in both the horizontal and vertical directions. This is approximately equal to the code-requirement minimum.Loading: a moment-shear ratio based on the ASCE-7 load distribution will be applied. This results in a design base shear of 2.5Agfc^.5, which is 60% of the ACI 318-05 specified capacity (i.e., a phi-factor of 0.6 was used in design). Note that application of the ASCE-7 load distribution requires applicaiton of moment and shear at the top of the wall as well as shear loads at the second and third floors. [less]

The performance assessment of bridge piers subjected to the complex loading combination of bending, shear, axial load and torsion has been a challenge to structural engineers. Analytical solutions that were developed for such combined loadings are no... [more]

The performance assessment of bridge piers subjected to the complex loading combination of bending, shear, axial load and torsion has been a challenge to structural engineers. Analytical solutions that were developed for such combined loadings are not sufficient and the lack of large scale experiments has deprived the community from the necessary resources to improve the models. To provide a context for this complex problem and to overcome limited laboratory capabilities, the pseudo dynamic (PSD) test method will be employed using the Multi-Axial Full-Scale Sub-Structured Testing and Simulation (MUST-SIM) facility. In addition, UI-SIMCOR, the NEES@UIUC simulation coordinator, will be utilized throughout the study. UI-SIMCOR is a robust tool for combining any number of experimental and analytical sites within an integrated simulation of a complex structure, its foundations and soil-structure interaction. The research program focuses on determining the impact of varying vertical motions on the shear-flexural-axial interaction behavior of bridge columns under combined loading. [less]

Design: Boundary elements have a longitudinal reinforcement ratio of 3.5% and tranverse reinforcement ratios of 1.0% (38% greater than required) in the in-plane direction and 0.92% (22% greater than required) in the out-of-plane direction. Wall web r... [more]

Design: Boundary elements have a longitudinal reinforcement ratio of 3.5% and tranverse reinforcement ratios of 1.0% (38% greater than required) in the in-plane direction and 0.92% (22% greater than required) in the out-of-plane direction. Wall web reinforcement ratios are is 0.27% in both the horizontal and vertical directions. This is approximately equal to the code-requirement minimum.Loading: a moment-shear ratio based on the ASCE-7 load distribution will be applied. This results in a design base shear of 2.5Agfc^.5, which is 60% of the ACI 318-05 specified capacity (i.e., a phi-factor of 0.6 was used in design). Note that application of the ASCE-7 load distribution requires applicaiton of moment and shear at the top of the wall as well as shear loads at the second and third floors. [less]

The performance assessment of bridge piers subjected to the complex loading combination of bending, shear, axial load and torsion has been a challenge to structural engineers. Analytical solutions that were developed for such combined loadings are no... [more]

The performance assessment of bridge piers subjected to the complex loading combination of bending, shear, axial load and torsion has been a challenge to structural engineers. Analytical solutions that were developed for such combined loadings are not sufficient and the lack of large scale experiments has deprived the community from the necessary resources to improve the models. To provide a context for this complex problem and to overcome limited laboratory capabilities, the pseudo dynamic (PSD) test method will be employed using the Multi-Axial Full-Scale Sub-Structured Testing and Simulation (MUST-SIM) facility. In addition, UI-SIMCOR, the NEES@UIUC simulation coordinator, will be utilized throughout the study. UI-SIMCOR is a robust tool for combining any number of experimental and analytical sites within an integrated simulation of a complex structure, its foundations and soil-structure interaction. The research program focuses on determining the impact of varying vertical motions on the shear-flexural-axial interaction behavior of bridge columns under combined loading. [less]

The performance assessment of bridge piers subjected to the complex loading combination of bending, shear, axial load and torsion has been a challenge to structural engineers. Analytical solutions that were developed for such combined loadings are no... [more]

The performance assessment of bridge piers subjected to the complex loading combination of bending, shear, axial load and torsion has been a challenge to structural engineers. Analytical solutions that were developed for such combined loadings are not sufficient and the lack of large scale experiments has deprived the community from the necessary resources to improve the models. To provide a context for this complex problem and to overcome limited laboratory capabilities, the pseudo dynamic (PSD) test method will be employed using the Multi-Axial Full-Scale Sub-Structured Testing and Simulation (MUST-SIM) facility. In addition, UI-SIMCOR, the NEES@UIUC simulation coordinator, will be utilized throughout the study. UI-SIMCOR is a robust tool for combining any number of experimental and analytical sites within an integrated simulation of a complex structure, its foundations and soil-structure interaction. The research program focuses on determining the impact of varying vertical motions on the shear-flexural-axial interaction behavior of bridge columns under combined loading. [less]

Design: Boundary elements have a longitudinal reinforcement ratio of 3.5% and tranverse reinforcement ratios of 1.0% (38% greater than required) in the in-plane direction and 0.92% (22% greater than required) in the out-of-plane direction. Wall web r... [more]

Design: Boundary elements have a longitudinal reinforcement ratio of 3.5% and tranverse reinforcement ratios of 1.0% (38% greater than required) in the in-plane direction and 0.92% (22% greater than required) in the out-of-plane direction. Wall web reinforcement ratios are is 0.27% in both the horizontal and vertical directions. This is approximately equal to the code-requirement minimum.Loading: a moment-shear ratio based on the ASCE-7 load distribution will be applied. This results in a design base shear of 2.5Agfc^.5, which is 60% of the ACI 318-05 specified capacity (i.e., a phi-factor of 0.6 was used in design). Note that application of the ASCE-7 load distribution requires applicaiton of moment and shear at the top of the wall as well as shear loads at the second and third floors. [less]

The performance assessment of bridge piers subjected to the complex loading combination of bending, shear, axial load and torsion has been a challenge to structural engineers. Analytical solutions that were developed for such combined loadings are no... [more]

The performance assessment of bridge piers subjected to the complex loading combination of bending, shear, axial load and torsion has been a challenge to structural engineers. Analytical solutions that were developed for such combined loadings are not sufficient and the lack of large scale experiments has deprived the community from the necessary resources to improve the models. To provide a context for this complex problem and to overcome limited laboratory capabilities, the pseudo dynamic (PSD) test method will be employed using the Multi-Axial Full-Scale Sub-Structured Testing and Simulation (MUST-SIM) facility. In addition, UI-SIMCOR, the NEES@UIUC simulation coordinator, will be utilized throughout the study. UI-SIMCOR is a robust tool for combining any number of experimental and analytical sites within an integrated simulation of a complex structure, its foundations and soil-structure interaction. The research program focuses on determining the impact of varying vertical motions on the shear-flexural-axial interaction behavior of bridge columns under combined loading. [less]