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This paper presents an experimental study on the multidirectional cyclic lateral-load response of repaired post-tensioned self-centering (SC) controlled-rocking cross-laminated timber (CLT) shear walls (SC-CLT walls). Three SC-CLT wall specimens were investigated: an initially undamaged SC-CLT wall with unreinforced wall panels, a repaired SC-CLT wall with steel-plate reinforcement, and a repaired SC-CLT wall with steel-plate reinforcement and steel bearing plates on the foundation. An evaluation of the experimental response of SC-CLT walls (with and without steel-plate reinforcement) under multidirectional cyclic lateral loading is presented, with emphasis on changes in lateral stiffness and strength caused by damage. Steel-plate wall panel reinforcement is investigated as a repair approach to restore the lateral stiffness and strength of damaged SC-CLT walls. Steel bearing plates are used to repair (or avoid) localized damage to a concrete foundation when a steel plate–reinforced SC-CLT wall rocks on the foundation. The damage mechanisms affecting the changes in lateral stiffness and strength of each SC-CLT wall specimen are discussed. Assessment of the experimental results demonstrate that these repair methods are effective in restoring the lateral stiffness and strength of a damaged SC-CLT wall 

Natural hazards, including hurricanes and earthquakes, can escalate into catastrophic societal events due to the destruction of the built environment. To minimize the impact of such hazards on vulnerable communities, civil infrastructure must be designed with performance criteria that prioritize public safety and ensure continuous operation. The National Science Foundation funded Natural Hazards Engineering Research Infrastructure (NHERI) program focuses on advancing the development of resilient infrastructure. The NHERI Lehigh Real-time Multi-directional Simulation Experimental Facility (EF) is one of the facilities within this program. The facility serves as an open-access research hub, offering advanced technologies and engineering tools to develop innovative solutions for natural hazard mitigation. It is uniquely equipped to perform large-scale, multi-directional structural testing in real-time using a cyber-physical simulation technique known as real-time hybrid simulation. This technique enables researchers to model entire systems subjected to dynamic loads at a full scale, allowing for realistic assessments of infrastructure responses to specific hazard scenarios and the development of effective mitigation strategies. This paper explores how cyber-physical simulation has revolutionized research in natural hazards engineering and its influence on engineering practices. It highlights several ongoing projects at the NHERI Lehigh EF aimed at enhancing community resilience in hazard-prone regions. The paper also discusses the planned expansion of the EF, which aims to broaden its focus to include a wider range of natural hazards, and infrastructure systems. This expansion will incorporate both physical and computational resources to enhance the understanding of fluid interactions in combined natural hazards and climate change impacts on coastal and offshore infrastructure. The NHERI Lehigh EF represents a transformative facility that is reshaping natural hazards research and will continue to play a pivotal role in the development of risk management strategies for more resilient communities. 

This dataset contains data from E-Defense shake-table tests of a full-scale, steel moment-resisting frame (MRF) supplemented with spines. Herein, the spines were pin-based columns with sufficient stiffness and strength to distribute plastic deformation evenly over the height of the MRF. The specimen was tested under two configurations: first, with the spine rigidly connected to the MRF; and second, with the spine connected to the MRF through Force-Limiting Connections (FLCs). The two structural systems were subjected to two ground motions adjusted to two different scales. The tests highlighted the expected benefits of spines as well as their drawbacks of inducing large floor acceleration in the MRF and large shear forces in the spines themselves. The tests also highlighted how the FLCs can mitigate such drawbacks of spines. The data may be used, for example, to reproduce the observations presented by the authors, to compare the dynamic response of the specimen with building specimens tested in other shake-table test programs, to validate numerical models against the measured specimen response, or to formulate classroom exercises on system identification of linear and nonlinear systems. 

This paper presents an experimental study on the multidirectional cyclic lateral-load response of post-tensioned self-centering (SC) cross-laminated timber (CLT) shear walls. SC-CLT shear wall damage states are introduced and qualitatively defined in terms of the repairs needed to restore the lateral-load response of the SC-CLT wall. A comparison between SC-CLT wall damage states under unidirectional (in-plane) and multidirectional (in-plane and out-of-plane) lateral loading is presented. The experimental results show that the initiation of SC-CLT wall damage occurs at smaller story drifts under multidirectional loading compared to unidirectional loading. Engineering demand parameters (EDPs) are used to quantify the SC-CLT wall damage states. Uncertainty in the EDP value when a damage state occurs is considered and quantified. Using the experimental results, component (i.e., a CLT wall panel corner) and system (i.e., an entire SC-CLT wall) fragility functions are developed and presented. 

Mid-rise moment resisting frames (MRF) which utilize supplemental pinned-base spines (spine) to prevent the formation of story mechanisms experience higher mode accelerations at near elastic spectral values. Force Limiting Connections (FLC) can be introduced to reduce the floor accelerations from the higher mode responses while having small impact on first-mode response and maintaining the story mechanism prevention from the spine. Results from nonlinear response history analysis (NRHA) of a 4-story MRF-Spine system show how floor accelerations for higher modes are reduced with the addition of FLC placed between the MRF and spine. Peak effective pseudo accelerations are utilized to show how pseudo spectral accelerations are reduced by the introduction of FLC. Full-scale testing of the 4-storyMRF-Spine structure supports the numerical results of theMRF-Spine andMRF-Spine-FLC numerical analyses. These results show the potential benefits of adding FLC to MRF-Spine systems. 

Driven by demand for sustainable buildings and a reduction in construction time, mass timber buildings, specifically cross-laminated timber (CLT), is being more widely used in mid-rise buildings in the US. Low damage post-tensioned self-centering (SC) CLT shear walls (SC-CLT walls) provide an opportunity to develop seismically resilient CLT buildings. Previous research focused primarily on the lateral-load response under unidirectional loading of isolated self-centering timber walls, without considering the interaction with the adjacent building structural components, i.e., the floor diaphragms, collector beams, and gravity load system. Buildings response under seismic loading is multidirectional and there are concerns that multidirectional loading may be more damaging to SC-CLT wall panels and the adjacent building structural components than unidirectional loading, which affects the potential seismic resilience of buildings with SC-CLT walls. A series of lateral-load tests of a 0.625-scale timber sub-assembly was conducted at the NHERI Lehigh Large-Scale Multi-Directional Hybrid Simulation Experimental Facility to investigate the the lateral-load response and damage of SC-CLT walls and the capability of the adjacent building structural components i.e., the floor diaphragms, collector beams, and gravity load system to accommodate the building response and the controlled-rocking of the SC-CLT walls under multidirectional lateral loading. 

ABSTRACT This data paper presents data obtained from E‐Defense shake‐table tests of a full‐scale, steel moment‐resisting frame (MRF) supplemented with Spines. Herein, the Spines were pin‐based columns with sufficient stiffness and strength to distribute plastic deformation evenly over the height of the MRF. The specimen was tested under two configurations: first, with the Spine rigidly connected to the MRF; second, with the Spine connected to the MRF through force‐limiting connections (FLCs). Each specimen configuration underwent earthquake simulations using ground motions with two scale factors. The tests demonstrated the expected benefits of Spines as well as the disadvantage of inducing large floor accelerations in the structure and large shear forces in the Spines. The tests also demonstrated how the FLCs can mitigate these disadvantages. This data paper reports an overview of the tests, data archive structure, and potential use of the data. The data can be used, for example, to reproduce the observations presented by the authors, to compare the dynamic response of the specimen with building specimens tested in other shake‐table test programs, to validate numerical models against the measured specimen response, or to formulate classroom exercises on system identification of linear and nonlinear systems. 

This project will develop a new structural system that will protect buildings, their contents, and occupants during large earthquakes and will enable immediate post-earthquake occupancy. This earthquake-resilient structural system will be particularly valuable for essential facilities, such as hospitals, where damage to buildings and contents and occupant injuries must be prevented and where continuous occupancy performance is imperative. The new system will use practical structural components to economically protect a building from damaging displacements and accelerations. The project team will collaborate with Japanese researchers to study the new system with full-scale earthquake simulations using the 3D Full-Scale Earthquake Testing Facility (E-Defense) located in Miki, Japan, and operated by the National Research Institute for Earth Science and Disaster Resilience. This project will advance national health, prosperity, and welfare by preventing injuries and loss of human life and minimizing social and economic disruption of buildings due to large earthquakes. An online course on resilient seismic design will be developed and offered through the American Institute of Steel Construction night school program, which will be of interest to practicing engineers, researchers, and students across the country. This project contributes to NSF's role in the National Earthquake Hazards Reduction Program. The novel steel frame-spine lateral force-resisting system with force-limiting connections (FLC) that will be developed in this project will control multi-modal seismic response to protect a building and provide resilient structural and non-structural building performance. This frame-spine-FLC system will rely on a conventional, economical base system that resists a significant proportion of the lateral load. The system judiciously employs floor-level force-limiting deformable connections and an elastic spine to protect the base system. Integrated experiments and numerical simulations will provide comprehensive understanding of the new frame-spine-FLC system, including rich full-scale experimental data on building seismic performance with combined in-plane, out-of-plane, and torsional response under 3D excitation. The FLCs will be tested using the NHERI facility at Lehigh University. This project will be conducted in collaboration with an ongoing synergistic research program in Japan. The extensive dataset from this integrated U.S.-Japan research program will enable unique comparisons of structural and non-structural performance, including critical acceleration-sensitive hospital contents that directly affect the health and safety of patients. In addition, the dataset will enable the advancement of computational modeling for the assessment of building performance and the development of practical, accurate models for use in design that capture the complex 3D structural response that occurs during an earthquake. 

This project will develop a new structural system that will protect buildings, their contents, and occupants during large earthquakes and will enable immediate post-earthquake occupancy. This earthquake-resilient structural system will be particularly valuable for essential facilities, such as hospitals, where damage to buildings and contents and occupant injuries must be prevented and where continuous occupancy performance is imperative. The new system will use practical structural components to economically protect a building from damaging displacements and accelerations. The project team will collaborate with Japanese researchers to study the new system with full-scale earthquake simulations using the 3D Full-Scale Earthquake Testing Facility (E-Defense) located in Miki, Japan, and operated by the National Research Institute for Earth Science and Disaster Resilience. This project will advance national health, prosperity, and welfare by preventing injuries and loss of human life and minimizing social and economic disruption of buildings due to large earthquakes. An online course on resilient seismic design will be developed and offered through the American Institute of Steel Construction night school program, which will be of interest to practicing engineers, researchers, and students across the country. This project contributes to NSF's role in the National Earthquake Hazards Reduction Program. The novel steel frame-spine lateral force-resisting system with force-limiting connections (FLC) that will be developed in this project will control multi-modal seismic response to protect a building and provide resilient structural and non-structural building performance. This frame-spine-FLC system will rely on a conventional, economical base system that resists a significant proportion of the lateral load. The system judiciously employs floor-level force-limiting deformable connections and an elastic spine to protect the base system. Integrated experiments and numerical simulations will provide comprehensive understanding of the new frame-spine-FLC system, including rich full-scale experimental data on building seismic performance with combined in-plane, out-of-plane, and torsional response under 3D excitation. The FLCs will be tested using the NHERI facility at Lehigh University. This project will be conducted in collaboration with an ongoing synergistic research program in Japan. The extensive dataset from this integrated U.S.-Japan research program will enable unique comparisons of structural and non-structural performance, including critical acceleration-sensitive hospital contents that directly affect the health and safety of patients. In addition, the dataset will enable the advancement of computational modeling for the assessment of building performance and the development of practical, accurate models for use in design that capture the complex 3D structural response that occurs during an earthquake.