Despite being located 21 kilometers from the epicenter of the 1994 Northridge earthquake (magnitude 6.7), the city of Santa Monica experienced anomalously concentrated damage with Mercalli intensity IX, an intensity as large as that experienced in the vicinity of the epicenter. Seismic records from aftershocks suggest that the damage resulted from the focusing of seismic waves by several underg...

In another work, the “open safe” of the HAZUS-MH methodology was cracked to create seismic vulnerability functions that honor all HAZUS-MH methodologies and data, yet that appear in the form of tables of mean casualty rates (indoor deaths and injuries as four fractions of total occupancy) versus a structure-independent intensity measure, in particular, Sa 0.3 sec,5% or Sa 1.0 sec,5% . In this w...

This paper focuses on an overview of kernel density estimation especially for what concerns the choice of bandwidth and intensity parameters according to local conditions. A case study inherent seismic risk analysis of the old town centre of Potenza hilltop town has been discussed, with particular attention to the evaluation of the possible local amplifying factors. This first integrated applic...

This study aims at determining the critical seismic intensity at which cracks are expected to develop in a concrete arch dam. This intensity is referred to as crack initiation intensity. The crack initiation intensity measure implies that earthquakes with the intensity measure higher than this value are expected to induce cracks in the arch dam. This quantity is an indicator for seismic evaluat...

Performance-based design is an efficient strategy for assessing and reducing the risk that a construction violates some performance requirement. In this paper, a procedure for performance-based assessment of seismic risk is illustrated with reference to a composite steel-concrete frame structure. Such risk is conventionally evaluated in a simplified formulation, i.e. as the mean annual frequenc...

Although naturally occurring vibrations have proven useful to probe the subsurface, the vibrations caused by traffic have not been explored much. Such data, however, are less sensitive to weather and low visibility compared to some common out-of-road traffic sensing systems. We study traffic-generated seismic noise measured by an array of 5200 geophones that covered a 7 × 10 km area in Long Bea...

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...

Seismic design may require non-conventional concept, due to the fact that the stiffness and layout of the structure have a great effect on the overall structural behaviour, on the seismic load intensity as well as on the internal force distribution. To find an economical and optimal structural configuration the key issue is the optimal design of the lateral load resisting system. This paper foc...