论文部分内容阅读
为研究结构钢在三轴应力状态下的断裂机理和抗断设防,对结构钢开孔管进行断裂拉伸试验和数值模拟分析。结果显示:初始裂纹都位于垂直于加载方向的圆孔周边的试件表面,最先出现初始裂纹的区域形成应力集中;在裂纹端部,形成空间应力,应力集中在圆孔的周边,应力三维度随着开孔半径的递增而增加。分析表明,应力三维度是影响材料出现初始裂纹的重要因素;同时发现,在裂纹端部第一主应力与材料的断裂强度比值为1.34~1.59,通过试验分析其原因。
In order to study the fracture mechanism and anti-break fortification of structural steel in triaxial stress state, the tensile test and numerical simulation of structural steel open-ended pipe were carried out. The results show that the initial cracks are all located on the specimen surface around the circular hole perpendicular to the loading direction, and the stress cracks occur in the area where the initial cracks first appear. At the crack tip, the space stress is formed and the stress concentrates on the periphery of the circular hole. The dimension increases as the radius of the opening increases. The analysis shows that the three dimensional stress is an important factor affecting the initial crack initiation. The ratio of the first principal stress to the fracture strength of the material at the crack tip is 1.34-1.59, and the reason is analyzed through experiments.