不同骨料混凝土剪切断裂试验及数值分析  

Experimental and Numerical Analysis of Shear Fracture of Concrete with Different Aggregates

作　　者：张海[1] 郝彩哲[2] 冯领香[1] 

机构地区：[1]天津大学建筑工程学院 [2]承德石油高等专科学校,河北067000

出　　处：《实验力学》2007年第6期581-587,共7页Journal of Experimental Mechanics

摘　　要：利用四点剪切加载的试验方法对不同骨料混凝土的双边切口试件进行了详细的试验研究。研究表明骨料不同的混凝土试件,其宏观断裂行为存在很大的不同,并且P-Δu曲线呈现出较大的差异,从而为进一步研究混凝土的断裂机理提供了参考。本文在试验研究基础上,建立了与试验模型相对应的三维有限元模型,利用有限元工程分析软件,对混凝土四点剪切的断裂力学行为进行了分析。结果表明,由于混凝土材料本身力学性能的特殊性-其抗拉强度较其抗压抗剪强度要低得多,所以裂纹尖端处的应力场分布状态是导致混凝土纯剪加载下的张拉破坏和剪切破坏的主要原因。This paper presents detailed studies of two-edge crack specimens with different aggregates by four-point shear loading experimental method. Results indicate that the primary crack macro-behavior is different due to concrete with different aggregates, and the P-△u curves are quite different. Hence, the paper provides reference to further studies of fracture mechanism. In addition, this paper presents a three-dimensional finite element model matching for tested specimen and various behavior of fracture mechanics of four-point shear specimens can be analyzed by the FEA software. Results show that because of the special mechanical properties of concrete-tension resistance is lower than the shear resistance, stress field at crack tip causes the breakage of tensile and shear under the condition of shear loading.

关 键 词：骨料 剪切断裂 P-△u曲线 数值分析 裂纹尖端 

分 类 号：TU31[建筑科学—结构工程]