Stress distribution in conical sand heaps at incipient failure under active and passive conditions
Stress distribution in conical sand heaps at incipient failure under active and passive conditions
复制标题
主动和被动条件下锥形砂堆初期破坏时的应力分布
DOI：
10.1016/j.ijsolstr.2018.04.001
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发表时间：
2018
影响因子：
3.6
通讯作者：
T. Kitaoka and H. Ohtsu
中科院分区：
文献类型：
--
作者：
T. Nguyen;T. Pipatpongsa;T. Kitaoka and H. Ohtsu
应力不连续性在平面和圆锥形散粒体堆中都起着重要的作用。本研究的目的是揭示在被动和主动条件下的应力分布在完全塑性锥形砂堆，服从莫尔-库仑屈服准则的数值解。在平衡方程组中加入Levy的周向应力假设，形成一对常微分方程组，并采用五阶自适应龙格-库塔法进行积分。此外，初始条件的数值摄动被放置到位，以克服积分的奇异性。在被动条件下进行试错迭代，以指示与应力跳跃条件的应用相结合的应力不连续的位置。同时，在主动条件下，采用了投篮技术，以促进整合。被动圆锥形砂堆的结果显示出在中心处的局部最小压力，从而启动拱作用。此外，主应力的轨迹直观地阐明了锥形砂堆中的荷载传递机制。阐述了被动条件下锥形沙堆中应力间断位置与休止角之间的线性拟合关系。
Stress discontinuity plays an important role in both planar and conical heaps of granular materials. The aim of this study is to reveal the numerical solutions for the stress distribution in fully plastic conical sand heaps that obey the Mohr-Coulomb yield criterion under both passive and active conditions. Levy's circumferential stress assumption was added to the system of equilibrium equations to formulate a pair of ordinary differential equations that were integrated by the 5th order adaptive Runge–Kutta method. Moreover, the numerical perturbations of the initial conditions were put in place to overcome the singularities of the integrations. Trial-and-error iterations were implemented under the passive condition to indicate the location of the stress discontinuity in conjunction with the application of the stress jump condition. Meanwhile, the shooting technique was employed to facilitate the integration under the active condition. The results of the passive conical sand heaps exhibit a local minimum pressure at the center, thus initiating arch action. In addition, the trajectories of principal stresses visually elucidate the mechanisms of load transfer in the conical sand heaps. The linear-fitting relationship between the location of the stress discontinuity and the repose angle in a conical sand heap under the passive condition was also elaborated.