Abstract:To study the influence of cooling methods on mechanical properties of recycled aggregate concrete(RAC) after high temperature exposure, 111standard cubic blocks were prepared. Several parameters of recycled coarse aggregate replacement rate, high temperature and cooling methods were taken in consideration in compression test after high temperature. Through the test, the appearance, failure pattern and mechanical properties of RAC with various cooling methods were observed. Influence rule of residual strength was analyzed and its corresponding calculation formulas was also proposed. Test results indicate that RAC surface color becomes light as the temperature rises, cracks and flaking degree increase. Mass loss rate tends from fast to slow under the condition of natural cooling, and in the case of water cooling, tends to a linear change. With the increase of temperature, the residual strength of RAC decreases gradually. Compared with natural cooling, residual strength is high to low before the change trend of high to low under water cooling. Based on test results, the residual strength calculation formula under different cooling methods are proposed respectively, which can be in good agreement with existing test data.