基于试验测定的混凝土热工参数反演计算

Back-Analysis of Concrete Thermal Parameters Based on Experimental Measurements

摘要:

热工参数的选取,对混凝土结构温度场和温度效应的分析结果有重要影响.为了选取更接近实际的热工参数，采用试验和反演分析相结合的方法,计算影响日照条件下混凝土结构温度场和温度效应分析结果的热工参数.基于一维热传导方程和热边界条件，假设混凝土表面附近温度分布为坐标的二次函数，建立导热系数、混凝土表面换热系数和混凝土表面太阳辐射吸收系数的反演方程;基于热膨胀系数的物理意义，建立其反演公式;最后，根据实测的温度、应变和气象数据,反分析计算一块混凝土板的热工参数.

Abstract:

Based on a test and back analysis,the thermal parameters close to practice can be obtained,which have great influence on the analysis results of temperature field and thermal effects for solar concrete structures.Assuming that the temperature distribution close to the concrete surface is the quadratic function of the coordinate,the back-analysis equations of thermal conductivity,heat transfer coefficient and absorption coefficient of solar radiation are derived based on one dimension Fourier equation of heat conduction and thermal boundary conditions.And the back-analysis equations for coefficient of thermal expansion is presented based on the physical explanation.Finally back-analysis of thermal parameters for a concrete slab is made through the measured temperature,strain and meteorological data.