中文摘要：

基于热力学和材料力学，分析了在盐冻循环、钢筋锈蚀与弯曲荷载协同作用下钢筋混凝土粱试样内部的热应力和机械应力分布及其损伤演变的规律，导出了钢筋混凝土在循环变温过程中不同方向的热应力的一般性计算公式及分布状态以及四点弯曲荷载下钢筋和混凝土各自承受的应力状态。分析结果表明温度应力沿梁试样长度方向非均匀分布，而弯曲应力与钢筋和混凝土的弹性模量之比有关。研究表明混凝土在盐冻循环、钢筋锈蚀与弯曲荷载协同作用下的损伤失效机理是温度疲劳导致的混凝土损伤以及腐蚀液渗透导致钢筋锈蚀共同作用引起的。

英文摘要：

Stresses in reinforced concrete beam under synergistic effects of cyclic freeze-thaw, deicing-salt attack, rebar corrosion and four-point bending were analyzed based on thermomechanics and mechanics of materials, and the distribution of these stresses with damage evolution in concrete were investigated. As a result, a series of formula for calculating thermal and mechanical Stresses in the concrete were presented. It was found that the thermal stresses are distributed nonlinearly along the length of the beam sample and that the bending stresses depend on the ratio of steel modulus to the concrete modulus. The results indicate that the damage of the concrete under the synergistic loads is a combination of thermal fatigue and corrosion penetration.