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The severe damage of conventionally designed buildings and consequent socioeconomic impacts after major seismic events have spurred the development of self‐centering systems with high seismic resilience. Post‐tensioned (PT) walls with rocking interfaces allowed to open and close and unbonded PT bars that provide most of the re‐centering ability have been developed extensively as a promising self‐centering technology. Aiming at providing essential insights into the seismic performance of self‐centering tube systems, a 1/6‐scale ten‐story self‐centering tube building was designed, constructed, and tested on a shaking table subjected to a series of unidirectional and bidirectional ground motions with increasing intensities. The test building consisted of a self‐centering tube that included four PT walls and provided the primary lateral force resistance in both directions, a perimeter rocking frame that was designed mainly to carry gravity loads, and particular connections with slots to accommodate the potential displacement incompatibility among the PT walls and surrounding components. The experimental results indicated the excellent seismic performance of the test building that had reliable structural integrity and experienced only confined damage even when subjected to extremely high intensities. The building also exhibited satisfactory re‐centering ability with minimal residual deformations at the conclusion of testing. It was demonstrated that the self‐centering tube system is a desirable low‐damage alternative to traditional tube systems in earthquake‐prone regions. The benchmark data from this test provided unique suggestions and support for further research on the design methods, numerical modeling, and experimental testing of self‐centering tube systems. [ABSTRACT FROM AUTHOR]

Summary: To support the development of low‐damage concrete structures, a system‐level shake‐table test of a two‐story concrete wall building implementing state‐of‐the‐art design concepts was conducted using the multi‐functional shake‐table array at Tongji University as part of an international collaborative project. The test building was designed with a perimeter frame and exterior post‐tensioned concrete walls in both directions. Different floor systems and wall‐to‐floor connections were incorporated in the test building to compare a number of design concepts and construction details. A range of energy dissipation devices were installed at the wall base and/or slotted‐beam joints of the test building. To simulate the test building response during the shake‐table tests, numerical models of the test building in both the longitudinal and transverse directions were established in OpenSees. Because the test building utilized flexible and isolated wall‐to‐floor connections that specifically reduced potential wall‐to‐floor interaction, planar frame numerical models were selected to represent the test building in each direction of loading. In the models, fiber hinge elements were used to simulate the unbonded post‐tensioned walls and a modified multi‐truss spring method was adopted to simulate the slotted‐beam joints with and without dampers. Inelastic time‐history analyses of the numerical models were conducted considering three earthquake intensities and comparisons of the test and simulation responses of the building are presented. The simulation results showed that the analytical model established in this study could reasonably predict both the global and local responses of the test building under different shaking intensities. [ABSTRACT FROM AUTHOR]

A shake-table test of a 2-story full-scale low-damage concrete wall building was conducted on the multifunctional shake-table array at Tongji University to validate the system-level dynamic response of this type of building. The test building implemented state-of-art low-damage structural systems, including post-tensioned (PT) precast concrete walls, precast concrete frames with slotted beam connections, and a variety of energy-dissipating devices. The building was subjected to 39 separate earthquake tests, consisting of a range of structural design configurations and ground motions including different intensity records, far-field and near-fault records, and short- and long-duration records. The test data and documentation recorded throughout the project have provided a significant high-quality data set for improving understanding both global and local response of post-tensioning concrete wall buildings. The data set has been published and is publicly available. The methodology of the test documentation and data collection for each stage of the project are described, and a road map for navigating the archived data set is provided to support its future use. [ABSTRACT FROM AUTHOR]

The increasing need to reduce damage and downtime in modern buildings has led to the development of a low‐damage design philosophy, where the earthquake loads can be resisted with damage confined to easily replaceable components. Post‐tensioned (PT) concrete walls have emerged as a popular low‐damage structural system that have been implemented in a range of buildings. In order to provide essential evidence to support the development of low‐damage concrete structures, a system‐level shake‐table test was conducted on a two‐storey low‐damage concrete wall building implementing state‐of‐art design concepts. The test building included PT rocking walls that provide the primary lateral‐load resistance in both directions, a frame that utilized slotted beam connections, and a range of alternative energy dissipation devices that were installed at wall base or/and beam‐column joints. The building was subjected to 39 tests with a range of intensity ground motions, incorporating both unidirectional and bidirectional ground motions on the structure with different combinations of wall strength and energy dissipating devices. The building performed exceptionally well during the intense series of tests, confirming the suitability of both the design methods and the connection detailing implemented. The building achieved an immediate occupancy performance objective even when subjected to maximum considered earthquake hazard shaking. The building exhibited only minor damage at the conclusion of testing, with distributed cracking in the floors and cosmetic spalling in the wall toes that did not compromise structural capacity or integrity and could be easily repaired with minimal disruption. The test has provided a rich dataset that is available for further analysis of the building response and validation of design methods and numerical models. [ABSTRACT FROM AUTHOR]