Study On Thermal Pysical Parameters And Temperature Stress Of Porous Cement Concrete Pavement Material

The thermal physical properties of the porous cement concrete since its openinterconnected pores, will have great changes when it’s compared with the ordinary cementconcrete, therefore, it’s essential to have an in-depth understanding on its thermal physicalparameters to determine its temperature stress and the distribution of the thermal field.This paper mainly focused on determinating thermal physical parameters and calculatingthermal stress on the porous cement concrete pavement. By means of laboratory experiments,I got temperature gradients and the thermal diffusivity coefficients at different temperaturesand humidtity of different sizes of coarse aggregate porous cement concretes andcement-stable macadam, afterwards, calculated their specific heat values, thermalconductivity coefficients, and coefficients of linear expansion. Finally, I used the software offinite element–ANSYS, set up three-dimensional models and obtained the temperaturestresses of the porous cement concrete pavement and the ordinary cement concrete pavement.The main research conclusions are: the size rules of temperature gradients are: heating,13.2>19>4.75>cement-stable macadam; cooling,13.2>4.75>19>cement-stable macadam; andmeasuring the temperature conductivity coefficient values of particle sizes of porous cementconcrete and cement-stable macadam specimens under different temperatures and humidity,calculating the values of the specific heat, thermal conductivity coefficients, the temperatureconductivity coefficients, specific heat values and thermal conductivity coefficients of particlesizes of specimens increasing with the rising of temperatures and humidity. The analysis andcalculations of two kinds of pavement structure temperature stress after using ANSYS finiteelement software are: Under the condition of the same plate length, the maximum temperaturestress of common concrete pavement is near to1.3times of porous cement concrete pavement,and the maximum warping deformation approximately equal.