基于拉伸、压缩、剪切单轴强度试验值的材料三参数广义强度准则

Three-parameter Generalized Failure Criteria Based on Tension,Compression and Shear Uniaxial Strength

基于材料的第一应力不变量和应力偏张量第二应力不变量,给出了同时考虑拉伸、压缩、剪切强度参数影响下的三参数广义强度准则。该强度准则公式严格满足纯拉伸、纯压缩、纯剪切情况下的强度值,在物理意义上体现了静水压力和静水拉力对材料强度的不同影响和剪切强度对应力偏张量的影响。基于此三参数广义强度准则,讨论了材料在各种典型应力状态下的强度包线,并同传统的强度准则进行了比较分析。最后,以ROHACELL闭孔PMI泡沫为例,给出了三种典型泡沫材料的强度破坏包线曲线和试验验证数据,比较结果证明,采用该强度准则可以较好地预测ROHA-CELL刚性泡沫材料的破坏强度。

Based on the spherical tensor invariant and the deviator tensor invariant, a three-parameter generalized failure criteria was obtained based on the tension, compression and shear uniaxial strength value. This generalized failure criteria satisfy the pure tension, pure compression and pure shear test strictly. The criteria incorporate both the hydrostatic tensor influence and the octahedral shear tensor. Then, some typical stress states are discussed and compared the strength envelope among the 3-P generalized failure criteria to the common criteria. Also three types ROHACELL PMI foam material strength test are presented to support the criteria, and confirmed that this criteria is more suitable for describing the material failure envelope of ROHACELL PMI foam material.