连续配筋混凝土路面早期力学响应现场测试与分析

Field Measurement and Analysis of Early-age Mechanical Response of Continuously Reinforced Concrete Pavement

为了确定环境荷载作用下连续配筋混凝土路面(CRCP)力学分析模型中的边界条件,对环境荷载作用下CRCP的早期应力、应变进行测试。将应变计植入无应力瓦中测试混凝土与应力无关的应变,将应变计纵向埋入CRCP不同深度处测试混凝土的总应变、钢筋的应变、混凝土的膨胀系数以及凝结时的温度和应变,并计算出混凝土的应力。结果表明:在进行环境荷载作用下CRCP应力、应变分析时,混凝土与钢筋不是完全粘结的,裂缝处不能采用固定或自由边界条件,测试出的裂缝处钢筋的应力可以直接体现在裂缝处边界条件中;路面开裂时混凝土的应力与直接拉伸强度比较接近。

In order to determine proper boundary condition in mechanical analysis of continuously reinforced concrete pavement（CRCP） under environmental loads,the strains and stresses of CRCP in early age under environmental loads were measured.Using strain gages embedded in half cylinders,the stress independent strains were measured.Using strain gages at different depths,the total strains in concrete,the strains in steels,the thermal expansion coefficient of concrete,temperature and strain at setting of concrete were measured.The stress of concrete was calculated.Results show that the steel is not completely bonded with concrete,the perfectly free or restrained boundary condition across cracking is not true,and the longitudinal steel strains across cracking will appear in boundary condition across cracking when analyzing the stress and strain of CRCP under environmental loads.The calculated concrete stress is close to the measured tensile strength.