Currently, seismic design of new European buildings follows a force-based approach, whilst the assessment of existing buildings is moving towards a displacement-based philosophy. In forcebased design, conservative estimates of the period of vibration should be produced such that the base shear force will be conservatively predicted from an acceleration spectrum, and thus the use of gross sectio...

Recent studies have highlighted the potential benefits of inelastic foundation response during seismic shaking. According to an emerging seismic design scheme, termed rocking isolation, the foundation is intentionally under-designed to promote rocking and limit the inertia transmitted to the structure. Such reversal of capacity design may improve the seismic performance, drastically increasing ...

Knee joints, the beam column connections found at the roof level of a moment resisting frame buildings, are inherently different from conventional interior and exterior beam column connections in the way that forces from adjoining members are transferred into joint and then resisted by the joint. A knee connection has two distinct load resisting mechanisms, each for closing and opening actions ...

Passive control methods can be utilized to build earthquake resistant structures, and also to strengthen the vulnerable ones. In this paper, we studied the effect of this system in increasing the ductility and energy dissipation and also modeled the behavior of this type of eccentric bracing, and compared the hysteresis diagram of the modeled samples with the laboratory samples. We studied seve...

Advanced finite element techniques are used to investigate the multi-hazard (earthquake and blast) performance of Concrete-Filled Steel Tubes (CFSTs) and Concrete Filled Double Skinned Tubes (CFDSTs) for bridge engineering applications. Specimens of both sections are analyzed using the finite element package LS-DYNA under similar seismic and blast loading. First, behavior of CFSTs recorded in s...

Introduction: In recent years, spacecraft observations of 'medium-sized' asteroids 951 Gaspra, 243 Ida, 253 Mathilde, and most importantly 433 Eros have shown the overriding dominance of impact processes with regard to the structure and appearance of these irregular bodies. In a previous work [1], I investigated the relatively unexplored area of seismic shaking as a cause for the downslope moti...

1. Project goals and objectives This project aimed at developing analytical models and methods for assessing the seismic response of electrical substation equipment connected by assemblies of rigid bus (RB) and flexible strap connectors (FSC) or slider connectors (SC). Also developed is a method to estimate the reliability of electrical substation systems subjected to stochastic earthquake load...

The current design formulas such as those provided by FEMA273/274 for building structures with supplemental viscous dampers were derived based on the shear building assumption. However, for medium-rise to high-rise buildings that deform in a combined form of shear and bending when subjected to seismic loading, the design using existing formulas may result into an actual damping ratio much lower...

Retrofitted bridge fragility curves provide a powerful tool for assessing the effect of retrofit measures on the seismic performance of different bridge types under a range of loading levels. Traditional methods for retrofit assessment typically evaluate the effectiveness of retrofit based on the performance of individual components. However, the use of fragility curves for retrofitted bridges ...

Displacement-based seismic design and assessment procedures require as key input parameter estimates of displacement capacities of the critical elements. The displacement capacities of unreinforced masonry (URM) walls are typically determined by means of quasistatic cyclic tests. This paper shows that for URM walls failing in shear the number of applied cycles in quasi-static cyclic tests influ...