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.

Seismic Vulnerability Assessment and Retrofit Recommendations for State Highway Bridges: Case Studies

Abstract: Much of Utah’s population dwells in a seismically active region, and many of the bridges connecting transportation lifelines predate the rigorous seismic design standards that have been developed in the past 10-20 years. Other states in the west have instituted seismic retrofit programs in response to damage to transportation networks in past California earthquakes. In a parallel report, seismic retrofit guidelines were developed for Utah based on the "Seismic Retrofitting Manual for Highway Structures" published by the Federal Highway Administration. In this report, representative case study bridges are evaluated in detail using the guidelines. The case study evaluations include the following for each bridge: (1) selection and presentation of analysis method, (2) development of numerical model in LARSA 4D and/or additional programs as needed, (3) evaluation of the seismic response of the unretrofitted bridge, (4) design of a possible retrofit scheme. The bridges evaluated include a four-span simply supported prestressed concrete girder bridge, a four-span continuous concrete T-beam, and an eight-span curved steel girder bridge with in-span pin and hanger joints. A variety of different evaluation methods are presented including linear response spectrum analysis for demand assessment, capacity spectrum method and pushover analysis for capacity assessment, and nonlinear response history analysis. A variety of retrofit techniques are presented including column jacketing, cable restrainers, selectively closing pin and hanger joints, and seismic isolation. The varied examples and techniques presented in this report are meant to be representative of assessment and applicable retrofit approaches for many of the bridges in the state inventory that may be seismically deficient.

Role of Energy Absorption in Reliability of Tall Columns

Abstract: Earthquake resistant design of key structures at major industrial facilities is often performed with an energy‐absorbing or strong‐motion dissipating mechanism in mind. The energy is usually dissipated through the deformation or damage of less critical components in order to prevent or decrease the potential of a more catastrophic failure of a structure. This paper presents a simplified approach for evaluating the effects of energy dissipation through deformations in foundation bolts of tall industrial columns subjected to strong earthquake ground motion. In particular, changes in the failure probability of a column in the more critical mode of skirt buckling are studied as a function of bolt yielding. The post‐yielding nonlinear response motion of the structure is considered in the failure probability evaluation. Although the procedure presented in this paper is applied to tall industrial columns, it can be used for a variety of other types of structures with only minor modifications.