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一、断裂力学的由来断裂力学是近20多年来逐步发展起来的一门新学科。它研究的对象是材料或结构中的缺陷。它要解决的问题是,为了使一个结构在实际的载荷下安全运行,什么样的和多大的缺陷或裂纹是允许的,应该采取什么样的安全措施。过去传统的结构设计方法主要考虑强度的要求,根据结构的实际情况,计算出最危险区域的运行应力,乘上一些安全系数,然后选择结构的材料和尺寸,使最大运行应力小于材料的屈服强度或极限强度。例如一般
First, the origin of fracture mechanics Fracture mechanics is the gradual development of the past 20 years, a new discipline. It is the study of the material or structural defects. The problem to be solved is, what kind of and how many defects or cracks are allowed in order for a structure to operate safely under actual loads and what kind of safety measures should be taken. In the past, the traditional method of structural design mainly considered the requirement of strength. According to the actual structure of the structure, the operating stress in the most dangerous area was calculated, multiplied by some safety factor, and then the structure and size were chosen so that the maximum operating stress was less than the yield strength of the material Or ultimate strength. For example