锈蚀钢筋混凝土小偏心受压构件承载力评估

Assessment of bearing capacity of corroded reinforced concrete little eccentric compressive members

根据压区纵向钢筋锈蚀导致混凝土胀裂的过程,将小偏心受压构件承载力退化分为混凝土未开裂阶段、开裂阶段和保护层剥落3个阶段;通过分析压区混凝土锈胀开裂前的双向应力状态,开裂后的剪、拉应力状态以及保护层剥落后的失效对小偏心受压柱承载力的影响,建立了相应阶段的构件承载力评估模型;给出混凝土锈胀开裂前的模型参数值并进行承载力计算,结果表明:混凝土锈胀开裂前小偏心受压柱的承载力退化可以忽略不计.将混凝土锈胀开裂后构件承载力模型计算结果与试验结果进行对比,符合良好.

According to the process of the concrete cracking induced by the longitudinal rebar corrosion, the bearing capacity degeneration was divided into three stages： pre-cracking, cracking and splitting. The assessment model of the bearing capacity of the little eccentric compressive concrete members is established, considering the effect of the bearing capacity affected by the biaxial stress condition in the stage of pre-cracking, the shear-tensile stress condition in the stage of cracking and the failure of the cover in the stage of splitting. The calculation of the bearing capacity is carried out by giving the parameter of the model in the stage of pre-cracking, and the result shows： the degeneration of the bearing capacity of the little eccentric compressive column in this stage can be neglected. The result of the model calculation and that of the experiment of the bearing capacity after the concrete cracking are compared, and they fit well.