Matsuoka-Nakai破坏准则的拓展应用

Matsuoka-Nakai破坏准则有两个缺点：一是没有考虑岩土类材料的内聚力对材料的强度贡献,二是它与子午面的交线是直线,基于此,提出了一个拓展的Matsuoka-Nakai破坏准则.该准则在保持Matsuoka-Nakai破坏准则优点的基础上,考虑了岩土类材料的内聚力对其破坏强度的影响,且在子午面上呈现为外凸的曲线形状,因而能更合理地模拟岩土类材料的强度特性.红砂岩的真三轴试验资料检测了该拓展的Matsuoka-Nakai破坏准则的有效性.最后借助该拓展的破坏准则,通过寻求试验强度与预测强度之间的误差函数最小值的方法,提出了一个评估试验中难以测准的岩土类材料抗拉强度的计算方法.

Extended application for Matsuoka- Nakai failure criterion

The Matsuoka-Nakai failure criterion has two disadvantages: the first is the criterion not including cohesion' contribution to failure strength,the second is a linear meridian on meridian plane. Based on improvement about the two disadvantages,an extended Matsuoka-Nakai failure criterion is proposed.Comparison test results of red sandstone with their predicting results show that the extended Matsuoka-Nakai criterion could capture important strength characteristics such as tensile stress,friction,and curved meridian et al.of geo-material with good accuracy.At last,through searching for the minimum value of error function between test and prediction data,the extended Matsuoka-Nakai failure criterion supports a new way to obtain tensile strength of geotechnical material which is usually difficult to be measured by tests.