Experimental And Theoretical Researches On Seismic Behavior Of Raw-soil Hybrid Structure Walls

Raw-soil hybrid structure is a raw-soil structure that replaces the traditional raw-soil material with modern building material in the key position,such as steel,concrete,etc.To retain the traditional earthen construction's benefits of green building and thermal performance,the seismic behaviour and damage ductility of hybrid structure need to be improved that could be adaptable for residential safety and environment requests of new period.The experimental research and theoretical analysis on raw-soil hybrid wall and its material have been done in this article.Two types of hybrid walls were designed and conducted under low cyclic and repeated static load.Numerical models based on the finite element method were also developed.The restoring force model and shearing resistance calculation method were proposed on the experimental and numerial results.The main contents of this thesis are listed as follows:(1)Considering the existing problems of traditonal earthen walls and the requirements in new period.The new concept of raw-soil hybrid structure and building methodology of two kinds of typically raw-soil walls,such as rammed earth and adobe walls,are proposed.(2)The experimental researches on optimum moisture content and uniaxial compression of the raw-soil material with different admixture in different proportions have been done.And one of the constitutive relations and its calculation formula of stress and strain were proposed according to the experiment results.(3)The building methodology proposed was verified by the model making and pseudo-static test of hybrid structure walls.Meanwhile the seismic performance of walls was analyzed,including failure modes,ultimate shearing capacity,deformation capacity,stiffness degradation and energy dissipation.(4)To effectively remedy the disadvantage of traditional raw-soil structure in lighting and ventilation,the issue of raw-soil hybrid wall with opening was investigated by tests.The failure characteristics and seismic performance of hybrid walls with changing opening rate have been studied and some conclusions are listed.(5)The numerical simulating models were established according to the failure modes of two typically raw-soil wall,rammed and adobe.The validity of models has been proven by comparing the test results and the stress distribution of these walls were researched.(6)The restoring model and shearing capacity calculation method of raw-soil hybrid wall were proposed based on the damage characteristics in the test,numerical simulation results and the influence of opening rate,materials mechanical property,aspect ratio,etc.The results could be used in raw-soil hybrid structure application.