Macro And Micro Test And Simulation Research On Basic Properties Of Insulation Concrete With Recycled Ceramic

The research on thermal insulation concrete with recycled ceramic coarse aggregate is beneficial to solve the problems of building energy saving and waste ceramic recycling,which conforms to the basic strategy of energy conservation,emission reduction and green development in China.Therefore,it is of great significance to strengthen the research on thermal insulation concrete with recycled ceramic coarse aggregate.In this paper,the basic mechanical properties,thermal insulation properties and micro morphology of thermal insulation concrete with recycled ceramic coarse aggregate are studied by adding Vitrified microspheres into the ceramic coarse aggregate concrete.The influence of the amount of Vitrified microspheres and the replacement rate of recycled ceramic coarse aggregate on the working properties,mechanical properties and thermal conductivity of thermal insulation concrete with recycled ceramic coarse aggregate is analyzed.The mechanical properties and thermal insulation properties of ordinary concrete with natural coarse aggregate are compared and analyzed.In order to further study the meso mechanical properties of thermal insulation concrete with recycled ceramic coarse aggregate,the polygonal random aggregate model is established by MATLAB program,and the finite element model of Thermal insulation concrete with recycled ceramic coarse aggregate is established by ANSYS.The elastic modulus and thermal conductivity of thermal insulation concrete with recycled ceramic coarse aggregate are analyzed by numerical simulation.The main research work are as follows:(1)The working performance,apparent density,mechanical performance and thermal insulation performance of thermal insulation concrete with recycled ceramic coarse aggregate are evaluated and compared with ordinary concrete materials.The working performance of recycled ceramic coarse aggregate concrete is characterized by slump;the determination of its mechanical properties includes compressive strength test,splitting tensile strength test,axial compressive strength test and elastic modulus test;the thermal conductivity of recycled ceramic coarse aggregate concrete is determined to reflect the thermal insulation performance of recycled ceramic coarse aggregate concrete.The working performance of thermal insulation concrete with recycled ceramic coarse aggregate is better than that of ordinary concrete,and the amount of vitrified beads can improve the working performance of concrete obviously.The mechanical properties of thermal insulation concrete with recycled ceramic coarse aggregate are weaker than that of ordinary concrete.The amount of vitrified beads and the substitution rate of ceramic coarse aggregate have adverse effects on the mechanical properties of thermal insulation coarse aggregate concrete.The thermal insulation performance of thermal insulation concrete with recycled ceramic coarse aggregate is better than that of ordinary concrete,which is mainly due to the incorporation of vitrified beads.(2)The microstructure of recycled ceramic thermal insulation concrete was analyzed by SEM,XRD and FTIR.There are many unhydrated cement particles in the microstructure of thermal insulation concrete with recycled ceramic coarse aggregate,and the pore system is poor,which has a negative impact on the macro mechanical properties of thermal insulation concrete with recycled ceramic coarse aggregate.There is no new phase in thermal insulation concrete with recycled ceramic coarse aggregate compared with ordinary concrete.Both the ceramic coarse aggregate and the vitrified microsphere can inhibit the production of C-S-H,which leads to the poor mechanical properties of thermal insulation concrete with recycled ceramic coarse aggregate.The vitrified beads promote the formation of tobermorite crystal in thermal insulation concrete with recycled ceramic coarse aggregate,and improve the thermal insulation performance of thermal insulation concrete with recycled ceramic coarse aggregate.Both vitrified beads and ceramic coarse aggregate lead to the increase of CH content in cement matrix,which leads to the decrease of mechanical properties of thermal insulation concrete with recycled ceramic coarse aggregate.(3)The results show that the numerical simulation of thermal insulation concrete with recycled ceramic coarse aggregate are consistent with the macro test results,which provides the possibility for further in-depth design and matching for the ideal recycled coarse aggregate thermal insulation concrete materials.