Numerical Investigation of Fracture Initiation and Propagation in Concrete due to Thermal Stress

摘要：

Thermal stresses induced by thermal mismatch and thermal gradient play an important role in the failure of concrete structures as temperature changes are take into account. The significant differences of thermal expansion coefficients, Youngs modulus and Poissons ratio, occurred between aggregates and mortar, lead to severe thermal or residual stresses which are large enough to break down the concrete. In this paper, a numerical model, named RFPA-Thermal code, is proposed for thermal stress analysis and thermal cracking prediction. The heterogeneity of concrete are take into account in the model by employ the Weibulls distribution law, and damage mechanics is used to model the damage evolution processes. The presented method is easy to predict the location where cracks are most likely to initiate and propagate, even the stress buildup, stress release and stress transfer in the model as temperature changes. The numerical model is used to predict the crack propagation of thick-wall as it subjected to thermal stress, and the results indicate that as the inner temperature is largerthan that of outer, thermal cracks will occurred at the outer-wall firstly, and extend gradually into the inner; on the contrary, if the inner temperature is lower than that of outer, cracks will initiated at the inner-wall firstly, and propagate to the outer-wall.

关键词： thermal stress Heterogeneous thermal cracking thermal-mechanical coupling

作者: TANG Shibin TANG Chunan LIANG Zhengzhao LI Lianchong Zhang Yongbin

作者单位: School of Civil and Hydraulic Engineering,Dalian University of Technology,Dalian 116024,Liaoning,China

会议类型: 国际会议

会议名称: The 2008 International Symposium on Safety Science and Technology(2008年安全科学技术国际会议)

会议地点: 北京

会议语种:英文

页码: 1879-1884

在线出版日期: 2008-09-24（万方平台首次上网日期，不代表论文的发表时间）