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A multimechanism, shear-assessment procedure has been developed by combining and modifying a shear-strength model for truss-tension failures with a softened strut-and-tie model for strut-co...

Reinforced concrete walls are a common lateral load–resisting system for buildings. Common wall configurations are solid planar or solid flanged (H, I, T, L, or C-shaped cross sections) and...

Experimental testing was conducted on four large-scale, flexure-yielding walls with rectangular cross sections to investigate the impact of imposed axial load ratio (10, 14, and 20% of axia...

Concrete walls are used commonly as part of the lateral-load resisting system for buildings in regions of high seismicity. Damage to walled buildings in recent earthquakes has highlighted t...

RC core walls are used commonly in modern building construction as the primary lateral load–resisting system. To meet architectural constraints, including elevator, stair, and doorway openings, common configurations include walls coupled together with heavily reinforced, low-aspect-ratio coupling beams. Numerous studies have focused on coupling beams and improved seismic performance and design of coupling beams. However, far fewer research programs have studied the seismic behavior of the coupled wall system. Coupled walls are typically used in mid- to high-rise construction, and understanding their seismic response requires simulation beyond the coupling beam and must include all important yielding components of the system. A research project was undertaken to investigate the response of a midrise coupled wall designed to meet current codes. The advanced testing capabilities of the University of Illinois at Urbana-Champaign George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES)...

A series of subassembly tests were conducted to investigate the behavior of the self-centering steel plate shear wall (SC-SPSW) system under cyclic loading. The SC-SPSW system utilizes thin steel web plates to provide energy dissipation and the primary strength and stiffness of the system, whereas posttensioned (PT) beam-to-column connections provide recentering capabilities. In this new system, the web plate is intended to yield under cyclic loading, whereas the boundary elements and PT connection elements remain undamaged. The web plate can then be replaced relatively easily following significant inelastic cycles. This experimental program studies the effects of various design parameters on the system and connection response and compares the response with approximate analytical formulas. The experimental results show that the SC-SPSW system has high ductility, high initial stiffness, recentering capabilities, an overall system response as anticipated, and more energy dissipation than expected.

The self-centering steel plate shear wall (SC-SPSW) is a new seismic load-resisting system that combines the strength and stiffness properties of the SPSW with the recentering capabilities of postt...

A model for use in simulating the response of reinforced concrete interior beam-column joints is developed and evaluated using an extensive experimental data set. This model builds on previous work by Lowes and Altoontash in 2003, modifying the previously proposed model to improve prediction of response and extend the range of applicability. First, a new element formulation is proposed to improve simulation of joint response mechanisms. Second, a new method for simulating the shear stress-strain response of the joint core is developed. This method assumes joint shear is transferred through a confined concrete strut and simulates strength loss due to load history and joint damage following yielding of beam longitudinal steel. Third, modifications are made to enable better simulation of anchorage zone response. Comparison of simulated and observed response histories indicates that the new model represents well stiffness and strength response parameters for joints with a wide range of design parameters.

A model is developed to represent the response of reinforced-concrete beam-column joints under reversed-cyclic loading. The proposed model provides a simple representation of the primary inelastic mechanisms that determine joint behavior: Failure of the joint core under shear loading and anchorage failure of beam and column longitudinal reinforcement embedded in the joint. The model is implemented as a four-node 12-degree-of-freedom element that is appropriate for use with typical hysteretic beam-column line elements in two-dimensional nonlinear analysis of reinforced concrete structures. Constitutive relationships are developed to define the load-deformation response of the joint model on the basis of material, geometric, and design parameters. Comparison of simulated and observed response for a series of joint subassemblages with different design details indicates that the proposed model is appropriate for use in simulating response under earthquake loading.

Steel plate shear walls (SPSW) are an efficient but largely underutilized building lateral force resisting system. The system consists of a moment frame (the boundary frame) with slender steel web plates that are welded or bolted inside the boundary frame, forming a diaphragm. The resulting structure resembles a vertical plate girder. The system resists lateral load primarily through tension field action of the postbuckled web plate. The magnitude and orientation of this tension field is governed by the relative stiffness of the web plate and boundary frame. The 2010 Seismic Provisions currently require that the tension field inclination angle be either 40° or computed using a closed-form equation derived from elastic analysis. It is demonstrated through experimentation and finite-element analyses that the tension field inclination may migrate, from an initially low angle under an elastic postbuckled state, toward 45° as the plate is loaded plastically. The resulting flexural demand on the vertica...