Research On The Thermal Properties Of Recycled Concrete

Recycled concrete is a sort of new economical construction material. Its thermal mechanical properties and thermo-physical properties are different from other concretes as a result of different property of the aggregate of recycled concrete and other concrete. For popularizing the application of recycled concrete, concerning the thermal mechanics properties and thermo-physical properties of recycled concrete, this paper focuses on the following aspects:(1) The research of the thermal mechanics properties and thermo-physical properties of recycled concrete both from home and abroad in recent years are reviewed and analyzed.(2) The color, crack and spalling of the recycled concrete after high temperatures are observed, from the tests, it was found that the color and crack of the recycled concrete were similar to those of normal concrete, and no spalling was found in all the tests.(3) Tests were done to study the properties of recycled concrete under high temperatures and after exposed to high temperatures, and hence obtained the laws and simulating formulas of the changes of recycled concrete properties, such as compressive and flexural properties. The curves of the relationship between the cube compressive and flexural strengths with temperatures were stated. The influence of the replacements of the recycled coarse aggregate and temperature to the residual compressive and flexural strength of the recycled concrete were studied.(4) The thermal mechanics properties of recycled concrete such as heat transferring coefficient and specific heat are theoretically investigated and evaluated. Thermal mechanics properties of recycled concrete with different replacements of the recycled coarse aggregate were calculated.(5) The thermal response the recycled concrete column at high temperature and the bearing capacity of the recycled concrete column are analyzed by ANSYS FE method. The temperature fields of the recycled concrete columns were analyzed based on the thermal mechanics properties of recycled concrete. And the thermal response and bearing capacity of the recycled concrete with different replacements of the recycled coarse aggregate were analyzed based on the temperature fields.