内压圆筒应力场对损伤萌生的影响

Influence of Stress Field of a Cylinder under Internal Pressure on Damage Germination

压力容器各部位因受力不同而具有不同的损伤萌生倾向。文中依据连续介质损伤力学的观点，提出以 Ｙ０＝ Ｕ· Ｒｃ 及ｇｒａｄ Ｙ０ 作为评价结构损伤萌生倾向的参数，其中 Ｕ是等效弹性比能， Ｒｃ 是与应力三轴度有关的函数。着重指出：不连续应力和热应力显著地提高内压圆筒的损伤萌生倾向。

Different locations on a cylinder under internal pressure are in different stress conditions,so the damaged tendencies are different.According to viewpoints of continuum damage mechanics,the parameters employed to express the tendency to be damaged of a structure are given as Y 0=.R c and grad Y 0;where is the equivalent elastic specific energy and R c is a function related to the stress triaxes degree.It is emphasized that the discontinuous stresses and thermal stresses increase the tendecy of damage germination on a cylinder under internal pressure remarkably.