THE PRECISE HEAT-FLUID COUPLING METHOD OF MASS CONCRETE WITH COOLING PIPES BASED ON LAYER-MERGED ELEMENT

The temperature gradient near cooling pipes in mass concrete can be taken into account by a heat-fluid coupling method, and then the pipe cooling temperature field of mass concrete can be accurately calculated. However, the preprocessor of the method is very complex and the amount of calculation is huge and inefficient by finite element simulation. A set of pre-processing and post-processing programs is developed to improve the heat-fluid coupling method, which based on concrete thermal and mechanical parameters changing with age and temperature distribution field of concrete by cooling pipes. By a layer-merged element, overall and local consistency models can be easily constructed and a temperature field can be precisely simulated in the program. Numerical examples show that the simulation method can not only ensure calculation accuracy, but also greatly reduces the simulation scale and improves efficiency. Thusly, it makes the precise simulation of a temperature field in mass concrete come true.