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SUMMARY An important component of probabilistic risk assessment methods is the development of models to quantify the direct consequences of damage to geo-structural components for a given intensity of the hazard. This paper presents a general probabilistic framework for correlated repair cost and downtime estimation of geo-structures exposed to seismic hazards. The framework uses as input the results of nonlinear time-history analysis of geo-structures for the set of earthquake records that are representative of the seismic hazard models for the region of interest. The repair cost and downtime are estimated for individual earthquakes probabilistically considering the uncertainties associated with damage states. In addition, the formulation of the repair cost and downtime accounts for the reduction in the repair requirements as the number of damaged components in the given damage state increases. An analytical linear and two bilinear regression models are proposed for conditional correlated seismic repair cost and downtime estimation of geo-structures given the intensity measure. The proposed framework is demonstrated by developing seismic repair models of a typical pile-supported wharf structure on the west coast of the United States. The presented framework is general and can be applied to other types of geo-structures and hazards and can include other decision variables such as loss of life as well. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Although the capabilities of engineering surface wave methods have improved in recent years due to several advances, a number of issues still require study to further improve the capabilities of modern surface wave methods. Near-field effects, which are one of these issues, have been studied for traditional surface wave methods with two receivers, and several criteria to mitigate the effects have been recommended. However, these criteria are not applicable to surface wave methods with multiple receivers. Moreover, the criteria are not quantitatively based and do not account for different types of soil profiles, which strongly influence near-field effects. A new study of near-field effects on surface wave methods with multiple receivers was conducted via numerical simulations, laboratory simulations, and field tests. Quantitatively based criteria for near-field effects in different soil profiles are presented using two normalized parameters developed in this study. There was excellent agreement between numerical and experimental results, and it was found that underestimation of measured Rayleigh phase velocities was the major symptom of near-field effects. [ABSTRACT FROM AUTHOR]