VULNERABILITY ESTIMATION OF HIGH-RISE STRUCTURES IN CASE OF NON-REGULAR DYNAMIC ACTIONS BY METHODS OF STATISTICAL SIMULATION

Development of methods of safety assessment of structures relative to nonregular natural, technogenic and terrorist influences of high intensity presents one of urgent scientific-technical problems. The dynamic reaction of structures under the action of extreme loads is highly nonlinear. The numerical statistical simulation appears to be the only way of vulnerability estimation. To reduce the computer modeling time an efficient Monte-Carlo simulation technique is applied for the estimation of failure probabilities. The method is based on splitting of samples at the stage of advance of sequential levels of viability on number of independently simulated samples. That makes possible to increase the number of failures for samples of relatively small volume and essentially reduce the time of statistical simulation. The models of high-rise structures, taking into account damage accumulation, development of inelastic deformations, large displacements, total or partial collapse, mutual pounding of closely-spaced structures are developed. Introduction into structural models of the most important non-linear factors allowed to take into account various mechanisms of structural collapse. The method for estimating the risk functions, based on the use of the developed models of high-rise structures together with algorithms of statistical simulation is suggested.