材料衍生比例定律的建立及其在结构屈曲断裂非线性失效中的应用

Establishment of derivative proportional law and its application in elastic-plastic buckling and fracture of structures

基于应变能定理和切线模量理论的内涵,研究应力应变曲线非线性阶段的实际应力和满足比例关系的线性应力之间的关系,可以得到不受比例极限限制的材料衍生比例定律。文中重点讨论该定律的建立过程,并引用大深度潜器耐压球壳弹塑性失稳进行了例证,最后说明该定律用于计算弹塑性断裂的方法以及与各断裂度量的关系。实例表明,结构非线性失效问题可以用衍生比例定律得到较好的解决。

Based on the strain energy theory and the connotation of tangent modulus theory,a new law called derivative proportional law of materials is established.This law is the innovation of Hooke＇s Law which is not limited by proportional limit of material and can reflect general view of stress-strain curve in- cluding linear part and nonlinear part.Using the relationship of real material stress and perfect elastic stress,the buildup process of derivative proportional law is discussed.This law can be used to calculate and analyze structure elastic-plastic buckling and elastic-plastic fracture by a four-parameter equation.Some experiment data indicate that the calculation values fit well with experiment results. So it is meaningful for practical application.