Experimental Analysis Of Physical And Thermal Properties Of Shale Ceramic Grain Concrete

In recent years,the urbanization process has been accelerated,the proportion of building energy consumption has been rising,and the promotion of building energy saving work is urgent.As a new material with properties of light weight,high strength,excellent heat preservation and durability,light-weight aggregate concrete is a good solution to meet the trend.Its application direction has shifted from thermal insulation envelope structure to load-bearing structure.According to loose volume method to calculate the initial mixture ratio,on the basis of the adjustment of sand ratio,water cement ratio and dosage of fly ash,and by using single factor method analysis test results of the cube compressive strength of concrete and the influence of the coefficient of thermal conductivity.Ten groups of shale ceramic grain concrete with a density level of 1800 were studied,and the linear correlation between dry apparent density and thermal conductivity was fitted.The ANSYS FLUENT software was used to analyze the steady-state numerical simulations of the typical thermal bridges in the shale ceramic grain concrete structures and compared with ordinary reinforced concrete.It was found that the shale ceramic grain concrete can reduce the heat loss to a certain extent under the self-insulation and internal insulation forms,but the effect of heat preservation in the form of external insulation is not obvious.Through the analysis,it is found that when self insulation exterior wall is adopted,insulation layer is set at the hot bridge area,because the heat flow on both sides of insulation layer is too large,it can not effectively reduce heat transfer coefficient of the thermal bridge,and energy saving effect is not obvious.Respectively for ordinary concrete and shale ceramic grain concrete under the common thermal insulation system,the wall temperature variation law of the wall in winter and summer was analyzed by non-steady-state method,and the analysis results were compared.In the 30 mm thick flame-retardant polystyrene board external insulation shale ceramic grain concrete wall,the daily change of the surface temperature of the wall in the summer is basically maintained at 25°C,to meet the human requirements for temperature comfort;In winter,the daily temperature range of the wall surface tends to be stable and maintained at 18?.It was not affected too much by changes in the outside temperature,and basically met the requirements of winter comfort.Finally,Dest-h energy simulation software was used to analyze building energy consumption of buildings when shale ceramic grain concrete was used as exterior wall load-bearing structures.The simulation results show that shale ceramic grain concrete replaces ordinary concrete as structural concrete,building energy consumption can be reduced by up to 20% in the heating season,and the heat preservation and energy saving effect is significant.