A Performance-Based Earthquake Engineering (PBEE) assessment methodology is being used to study the impact of long-term material degradation on seismic performance of reinforced concrete bridges. The methodology, currently under development by the Pacific Earthquake Engineering Research Center, is being applied to an overpass with typical California highway details, and preliminary results are ...

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 ...

Pseudostatic analysis is one of the simplest approaches used in earthquake engineering to analyze the seismic response of soil embankments and slopes. However, the choice of seismic coefficients used in the analysis can be arbitrary and generally lacks rationale. To investigate this, a parametric study was performed on a soil embankment of varied geometric characteristics and soil properties su...

Interaction between a structure under base excitation and heavy non-structural elements that it supports is significant in the seismic analysis and design of the structure. Heavy non-structural elements may slide/rock under base excitation, and this dynamic action affects the seismic behavior of the supporting structure. Hence, in this study, a numerical model was presented to describe the seis...

All variable capacitance accelerometers have certain basic design elements in common. They incorporate a seismic mass whose motion in response to shock or vibration lags behind that of the accelerometer housing. The capacitor consists of two plates, one attached to the outer frame and therefore stationary and the other attached to the seismic, or inertial, mass. The value of this capacitor is a...

fragility curves represent the probabilities that structural damages, under various levels of seismic excitation, will exceed the specified damage states by means of earthquake intensity damage relations. conceptual aspects related to seismic vulnerability, damage and risk evaluation are discussed first, together with a short review of the most widely used possibilities for the seismic evaluati...

zipper braced frames are an innovative bracing system for steel structures. conventional inverted-v-braced frames exhibit a design problem arising from the unbalanced vertical force generated by the lower story braces when one of them buckles. this adverse effect can be mitigated by adding zipper columns or vertical members connecting the intersection points of the braces above the first floor....