【作者】 王灿； 孙士勇； 陈浩然；

【Author】 Wang Can,Sun Shiyong,Chen HaoRan (State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology,Dalian 116024)

【机构】 大连理工大学工业装备结构分析国家重点实验室；

【摘要】 应用无网格Galerkin法对单轴远场拉应力加载下双材料裂纹平面问题进行了分析,通过在裂纹周围采用扩充了的基函数以及在裂纹尖端局部加密节点提高了位移场的计算精度,采用位移场数值外推法得到应力强度因子,避开了裂纹尖端应力场的奇异性和振荡性。与界面平行的裂纹在距离界面较远处的应力强度因子可视为Ⅰ型,而当平行裂纹逐渐靠近界面时复应力强度因子K为Ⅰ型和Ⅱ型的耦合。对具有不同泊松比、弹性模量比的几种材料组合,研究了平行裂纹位于较软材料1中、较硬材料2中不同位置以及界面上时裂纹尖端位移场、应力场和应力强度因子,讨论了裂纹位置分别从较软材料和较硬材料靠近界面时应力强度因子随裂纹到界面距离与裂纹长度之比d/a的变化规律。通过数值算例和与其他方法的比较,表明了在求解双材料界面裂纹问题中无网格Galerkin法精度可靠,计算简便的优点。更多还原

【Abstract】 Element-free Galerkin Method with penalty method was employed to investigate a rectangle thin bi-material plate with a crack paralleled to the interface.The effects of location of the crack for certain material combination and the effects of material combination for certain crack location on the value of stress intensity factor at the crack tip were discussed.The numerical results show that: （1） For certain material combination,K_Ⅱis increasing obviously and the change of K_Ⅰis not evident when the crack close with the interface. （2） For certain crack location and certainμ₁:μ₂,there is a direct ratio between K_Ⅰand E₂/ E₁（E₂>E₁） when the crack located in the soft material 1,while a direct ratio between K_Ⅰand E₁/ E₂（E₂>E₁） when the crack located in the other harder material 2;however K_Ⅱis always increasing with E₂/E₁（E₂>E₁） increasing. （3） For certain crack location and E₂/E₁（E₂>E₁）,the change of K_Ⅰis not evident and K_Ⅰis increasing withμ₁:μ₂（μ₁>μ₂） increasing when crack located in the relative soft material 1.更多还原