受力状态下混凝土试件碳化试验研究  

Experimental Research on Carbonation of Forced Concrete Specimens

作　　者：田浩[1] 李国平[1] 刘杰[1] 吴用贤[1] 

机构地区：[1]同济大学桥梁工程系,上海200092

出　　处：《同济大学学报（自然科学版）》2010年第2期200-204,213,共6页Journal of Tongji University:Natural Science

基　　金：西部交通建设科技项目(200631822302-01)

摘　　要：为了研究混凝土桥梁的碳化规律,采用加速碳化试验方法,进行了碳化环境下受力状态混凝土试件的耐久性试验,分析了碳化混凝土的退化机理和规律.结果表明:拉、压应力分别加快和减缓了混凝土碳化的速率,且应力变化越大,碳化速率的改变就越大;桥梁常用C50强度混凝土的碳化深度远小于低强度混凝土,但C50强度混凝土受拉时的相对碳化深度大于低强度混凝土.根据试验结果修正了现有混凝土碳化深度预测模型中的工作应力影响系数.当混凝土桥梁的裂缝宽度满足规范要求时,裂缝对混凝土碳化的影响很小;预应力混凝土桥梁的耐久性能优于钢筋混凝土桥梁.The durability experiments of forced concrete specimens in accelerated carbonation corrosive environments were carried out to investigate the carbonation regularity of concrete bridges. The degradation mechanism of carbonized concrete was analyzed. The results show that tensile or compressive stress can accelerate or slow down carbonation rate, respectively. Larger changes of stress will cause larger changes of carbonation rate. The carbonation depth of bridgecommon used C50 strength concrete is far smaller than that of low strength concrete but the relative carbonation depth of C50 strength concrete applied tensile stress is larger than that of low strength concrete. According to the tests, the working stress influence coefficient in existing concrete carbonation depth prediction model was modified. The crack in concretebridges has little effect on concrete carbonation if its width can meet standard requirements, and the durable performance of prestressed concrete bridges is better than reinforced concrete bridges.

关 键 词：混凝土试件 碳化试验 受力状态 C50强度混凝土 工作应力影响系数 裂缝 

分 类 号：TU375.1[建筑科学—结构工程]