Performance Of Concrete In Concrete Thermal Insulation Curtain Wall Experimental Study

In recent years,with the continuous development of building energy conservation in China,external thermal insulation technology has become the mainstream.In order to overcome the shortcomings of traditional insulation technology,Researchers have developed concrete thermal insulation curtain wall(also known as separated concrete wall),which has achieved good economic benefits in the actual projects in the area.However,the properties of concrete in the wall of concrete thermal insulation curtain wall need to be studied.In order to guarantee the construction quality of concrete in separated wall,this study draws up the test plan according to the construction technology of concrete in site,The performance of concrete in concrete thermal insulation curtain wall is studied by means of orthogonal design and comparative test.The factors of orthogonal design experiment are: water-binder ratio(0.40,0.42,0.45),sand ratio(30%,33%,35%)and slag replacement ratio(10%,20%,30%).The influence of various factors on workability and strength of concrete is studied and the optimum mix ratio of concrete is determined.The test results show that the water-binder ratio is the main factor affecting the compressive strength,followed by the sand ratio,and the sand ratio has the greatest impact on workability.The optimum mixing ratio is 0.42water-binder ratio,33% sand ratio and 20% slag substitution ratio.On the basis of orthogonal design experiments,the comparative experiments were carried out to study the effects of different concrete separation rates(0,1/4,1/5,1/6)on the mechanical properties of benchmark concrete and secondary concrete.Secondly,the influence of sieve residue coarse aggregate gradation and void ratio on the performance and mechanical properties of secondary concrete is analyzed.The experimental results show that with the decrease of concrete separation rate,the28-day compressive strength of secondary concrete increases gradually,the change trend of axial compressive strength is basically consistent with that of cubic compressive strength,and the flexural strength increases first and then decreases.The content of coarse aggregate can promote the splitting tension of secondary concrete,For the gradation test of sieve residue coarse aggregate.When the gradation of coarse aggregate in sieve residue concrete is the best,When the void fraction is thesmallest,the mechanical properties of secondary mixing concrete reach the best.With the decrease of void ratio,the compressive and splitting tensile properties of secondary mixing concrete gradually increase.Under certain conditions,the interfacial bonding between aggregate and mortar matrix has less influence on the elastic modulus of concrete,and the gradation and voidage of residual coarse aggregate play a dominant role.Secondly,when the void fraction of coarse aggregate is the lowest and the apparent density is high,the performance of secondary concrete is better.Through the above tests,the working performance and mechanical properties of concrete in concrete thermal insulation curtain wall are systematically analyzed and summarized,which can provide some experimental reference for further optimizing the construction technology of concrete in concrete thermal insulation curtain wall..