摘要
本文利用弹塑性边界元分析方法 ,对具有不同硬化系数的线性硬化结合材料界面端进行了计算。分析结果表明 ,当硬化系数较大时 ,界面端附近的弹塑性应力与将弹塑性本构关系简化为线性后得到的理论结果相接近 ,而当硬化系数相对较小时 ,理论分析的奇异应力场的主控区变得非常小 ,在屈服域的绝大部分区间 ,应力奇异性与理论解有较大区别。本文的结果还表明 ,硬化系数越小 ,过渡区 (弹塑性奇异应力场支配区到屈服边界 )越大 ,屈服区域应力分布变得平坦。在小规模屈服条件下 ,屈服区域外的弹性应力分布与不考虑塑性屈服的弹性奇异应力分布相似 (即奇异次数与弹性奇异次数一致 ) ,即可用弹性奇异应力场来近似地描述小规模屈服时的弹塑性界面端 ,但应力强度系数则比弹性时略大 ,且随硬化系数的减小而增大。
Using the elasto\|plastic boundary element method, numerical analysis on the interface edge of bonded materials with different hardening coefficient were carried out. The results show that when the hardening coefficient is relatively large, the elasto\|plastic stress near the interface edge is close to the theoretical solution, which is derived from the simplified constructive relationship. While the hardening coefficient is comparatively small, the theoretical zone controlled by singular stress becomes fairly small, and the singularity differs from the theoretical solution to a considerable extent in most of the field. The results also show that as the hardening coefficient decreases, the transitionally zone becomes larger and the distribution of the stress in the yield zone becomes more plat. Under small\|scale yield condition, the stress distribution outside the yield zone is similar to singular stress distribution without considering the plastic yield. So the elastic singular stress field can be used to narrate the elasto\|plastic stree field approximately under small scale yield condition, but the stress intensity coefficient is larger that the elastic one, moreover, it increases as the hardening coefficient decreases.
出处
《计算力学学报》
CAS
CSCD
北大核心
2001年第2期156-161,共6页
Chinese Journal of Computational Mechanics
基金
国家教委优秀青年教师基金资助
