Seismic waves are filtered as they pass through soil layers, from bedrock to surface. Frequencies and amplitudes of the response wave are affected due to this filtration effect and this will result in different ground motion characteristics. Therefore, it is important to consider the impact of the soil properties on the evaluation of earthquake ground motions for the design of structures. Soil ...

In this study, the effect of earthquake frequency content and noise effects on damage detection has been investigated. For this purpose, the damage was defined as nonlinear behavior of beams and columns, and several ground motion records were scaled so that some elements yield under the applied excitation. Then the acceleration response data of each floor obtained using the nonlinear dynamic an...

This paper presents a practical methodology for optimization of concentrically braced steel frames subjected to forward directivity near-fault ground motions, based on the concept of uniform deformation theory. This is performed by gradually shifting inefficient material from strong parts of the structure to the weak areas until a state of uniform deformation is achieved. In this regard, to ove...

This paper presents investigation carried out, including experimental and numerical studies, on low-rise shear-dominated brick masonry structures for the calculation of force reduction factor R. Basic experimental tests were conducted on masonry constituent materials for mechancial characterization. In-plane quasi-static cyclic tests were conducted on twelve full scale brick masonry walls, to u...

Following the 1994 Northridge and 1995 Kobe earthquakes, most of modern structures damaged seriously or devastated totally despite the seismic codes of these countries that had been expected to bear advanced criteria for seismic design of structures. After extensive research, the most probable reason of those destructions was attributed to special specifications of near-field earthquakes. In th...

The double impulse is introduced as a substitute of the fling-step near-fault ground motion. A closed-form solution of the elastic–plastic response of a structure on compliant (flexible) ground by the “critical double impulse” is derived for the first time based on the solution for the corresponding structure with fixed base. As in the case of fixed-base model, only the free vibration appears u...

Recent investigations have shown that the influences of Soil-Structure Interaction (SSI) may be detrimental to the seismic response of structure, and hence neglecting this phenomenon in analysis and design may lead to an un-conservative design. The objective of this paper is to quantify the effects of nonlinear soil-structure interaction on the seismic response of a low-rise special moment fram...

A method is proposed for exchanging information that allows a ground system to estimate the aircraft intent response to a ground instruction. This method approximates the intent response as a linear function of ground instruction parameters. The approach is described and applied to the case of an aircraft in climb subject to a controlled time-of-arrival. When subject to either lateral maneuvers...

Long-span bridges, as vital structures, play a very important role in economic development. Furthermore, the results of several earthquake-damaged bridges showed that their seismic behavior was different from that predicted under uniform excitation and in some cases the responses were more than predicted results. Therefore, the damaged bridges under non-uniform excitations were re-analyzed and ...