Earthquake resistant structures

About: Earthquake resistant structures is a research topic. Over the lifetime, 1126 publications have been published within this topic receiving 27467 citations.

Design, Analysis, and Seismic Performance of a Hypothetical Seismically Isolated Bridge on Legacy Highway

Abstract: The need to maintain the functionality of critical transportation lifelines after a large seismic event motivates the strategy to design certain bridges for performance standards beyond the minimum required by bridge design codes. To design a bridge to remain operational, one may stiffen and strengthen the load carrying members to increase the capacity, or alternatively use response modification devices such as seismic isolators to shift the dynamic characteristics of the bridge, henceforth reducing the seismic demands. Seismic isolation systems are attractive because they are directly conducive to accelerated bridge construction techniques. The two strategies are compared for a typical Utah highway bridge, using a three-span, pre-stressed concrete girder bridge that crosses Legacy Highway as a case study example. The existing Legacy Bridge, which was designed as a Standard bridge for a 2500-year return period earthquake, is evaluated as an Essential bridge for a 1000-year return period earthquake. Subsequently, this bridge is redesigned and evaluated as a seismically isolated bridge. Configuration changes needed to accommodate a seismic isolation system are discussed, and reductions to column and foundation elements are proposed. Example seismic isolator designs are provided for several different types of isolation systems commonly used in the United States. Inspection and maintenance practices for seismically isolated bridges are discussed.

Bidirectional Seismic Behavior of Controlled Rocking Four-Legged Bridge Steel Truss Piers

Abstract: The behavior and design of four-legged controlled rocking bridge steel truss piers to three components of seismic excitation are presented in this paper. The controlled rocking approach for seismic protection allows a pier to uplift from its base, limiting the force demands placed on the bridge pier and deck, and can allow the structure to remain elastic during an earthquake, preventing damage toward the goal of keeping the bridge operational immediately following the earthquake. Passive energy dissipation devices [steel yielding devices (SYDs) or fluid viscous dampers (VDs)] are used at the uplifting location to control pier response. The bidirectional kinematic and hysteretic cyclic behavior of controlled rocking piers with SYDs is presented and verified with nonlinear static pushover analysis. This fundamental behavior is used to develop design equations to predict peak pier displacements, uplifting displacements, and forces (frame shear and leg axial force). Dynamic response history analyses are performed, compared with the design equations, and shown to provide reasonably accurate results for design. The use of fluid VDs in the controlled rocking system is then discussed.

Behaviour and design of coupled slab-structural wall systems

Abstract: This paper presents the results of tests on nine reinforced concrete slab-coupled structural wall subassemblages subjected to gradually applied reversing displacements simulating earthquake loading