Experimental Study On Seismic Performance Of Recycled Concrete Brick Composite Wall Under Freeze-thaw Environment

With the advantage of simple material, convenient construction, flexible layout,good mechanical performance and economic cost, Masonry structure has been one ofthe most important types of building structures and been widely used in the worldwide.With the increasing of building age, The seismic performance of masonry structureswould degrade to some extent, seen from the earthquake in recent times, Shear failureand even whole collapses in masonry structure caused great casualties and economiclosses, So the durability degeneration of masonry structures had great influence onseismic performance and could not be ignored.Four recycled concrete brick combination wall were designed and produced in thepaper and the seismic performance, including destruction process and characteristics,stiffness degradation, seismic capacity attenuation, energy dissipation, ductility and soon, under cycle loading was studied in different freeze-thaw cycles. Test results showedthat Specimens ultimate bearing capacity and energy dissipation capacity decreased;Strength and stiffness deterioration also decreased obviously with the increasing offreeze-thaw cycles. The research results can not only provide reference for theevaluation of seismic reliability of existing masonry structures, but also providetheoretical support for the improvement of the relevant code in the future.Furthermore, Based on the advantages and disadvantages of current restoring forcemodel, A renewable three linear restoring force model considered freeze-thaw cycleswas proposed and the feature points, the formula of loading and unloading stiffness and circulation degradation rules for the model was given, which could provide theoreticalsupport for seismic response analysis of the masonry structures considered freeze-thawcycles in the future.With the application of finite element software ABAQUS, appropriate material andmeshed model, the constitutive model was created and the seismic performance ofcombination walls under different freeze-thaw cycles was analyzed through thecomparison between the experimental results and FEM results. The results can providetheoretical support for masonry structure seismic response analysis in differentdegradation, different design parameters and different loading systems consideredfreeze-thaw cycles.