Mazen R. Stressed-deformed state of multistory buildings on multi-stratified bases under seismic effects

The dissertation is devoted to creation of principles of correct modelling and calculation of multi-storey buildings in view of properties of the multilayered soil basis and its lamination in conditions of seismic influence, and also development of rational constructive decisions. The offered design procedure of multi-storey ferro-concrete buildings on influence of static and seismic loadings is based on use of a method of final elements. It enables in a complex to count system "soil - foundation - construction", considering spatial character of its work, and also the factor of influence soils with the inertial properties. Necessary parameters of the basis in seismic calculations of system "soil - foundation - construction" depending on parities of weights of elevated and underground parts and rigidity of the basis are analytically proved. The estimation of sensitivity of ferro-concrete multi-storey buildings with various constructive schemes to seismic influences is executed. Influence of lamination of the basis on the periods and forms of free fluctuations of system "soil - foundation - construction" is analysed. It is noted, that at the account of the soil basis and without this account of the form and the periods of fluctuations of buildings strongly differ.The numerical experimental researches which have confirmed an acceptability of the developed technique of an estimation of a stress-deformed state of buildings at seismic influences are lead. Check of a technique is carried out by comparison of data of the machine analysis to a real picture of the SDS of the buildings which have suffered at Spitak's earthquake of 12/7/1988. In the dissertation a number of recommendations on optimization of constructive decisions of buildings and their separate elements is offered.