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.

Direct Displacement-Based Seismic Design of unbonded Post-Tensioned Masonry Walls

Abstract: Post-tensioned masonry walls exhibit desirable seismic performance characteristics due to increased in-plane strength and the absence of residual lateral displacement at the conclusion of seismic loading. The direct displacement-based design (DDBD) approach aims to provide a method whereby a structure may be designed to achieve a predefined level of lateral deformation under a predefined level of earthquake intensity. This paper details the development of a DDBD procedure to assist in the design of unbonded post-tensioned masonry structural walls. The level of initial tendon prestress is shown to have a significant effect on wall response and guidance is provided for making this design choice. An acceptable correlation is demonstrated when the results from the method are compared with actual data obtained from previous shake table testing of three full-scale concrete masonry walls. The paper concludes by presenting a design example that highlights the steps involved in applying this approach to an actual wall structure and demonstrates the simplicity of the method.

Emergence of the semi-empirical technique of strong ground motion simulation: A review

Abstract: High frequency ground motion simulation techniques are powerful tools for designing earthquake resistant structures in seismically active regimes. Simulation techniques also provide the synthetic strong ground motion in the regions where actual records are not available (Kumar et al. 2015).These techniques require several parameters of earthquake and other seismic information proceeding to the simulation. Practically estimation of parameters is a tough task, particularly in a region with limited information. This demands a simulation technique based on the easily estimated parameters for a new site. The purposes of this paper are to briefly review existing simulation techniques and to discuss in detail the new, simple and effective semi-empirical technique (Midorikawa 1993) of strong motion simulation.

An Introduction to the Methodology of Earthquake Resistant Structures of Uniform Response

Abstract: Structures of Uniform Response are special earthquake resistant frames in which members of similar groups such as beams, columns and braces of similar nature share the same demand-capacity ratios regardless of their location within the group. The fundamental idea behind this presentation is that seismic structural response is largely a function of design and construction, rather than analysis. Both strength and stiffness are induced rather than investigated. Failure mechanisms and stability conditions are enforced rather than tested. Structures of Uniform Response are expected to sustain relatively large inelastic displacements during major earthquakes. A simple technique has been proposed to control and address the gradual softening of such structures due to local/partial instabilities and formation of plastic hinges. In structures of uniform response, the magnitude and shape of distribution of lateral forces affects the distribution of story stiffness in proportion with story moments, therefore affecting the dynamic behavior of the system as a whole. Simple closed form formulae describing the nonlinear behavior of moment frames of uniform response have been proposed. While the scope of this contribution is limited to moment frames, the proposed method can successfully be extended to all types of recognized earthquake resisting systems.

Observed Response of Actively Controlled Structures

Abstract: Several active control systems have been developed, fabricated, and installed in full-scale structures and they have been subjected to actual wind forces and ground motions. The focus of this paper is on the observed response of one of these systems, an active bracing system, which was subjected to several recent earthquake episodes. It is shown that the active system performs, by and large, as expected, and its performance can be adequately predicted through simplified analytical and simulation procedures. The observed performance of the active bracing system is also compared with that of another system, an active mass damper, which was installed in the same structure.