土体抗拉张力学特性研究进展

在传统土力学的观念中,土体通常不主动作为抗拉材料使用,土的抗拉强度很小,因而土体的抗拉强度往往被忽略或几乎视为零,造成土体抗拉强度理论远落后于抗剪强度理论。实际上,土体的抗拉张力学特性在土体变形与破坏的过程中起着非常重要的作用。总结了土体抗拉张力学特性试验的发展过程及发展特点,介绍了土体抗拉张力学试验的最新进展,并结合非饱和土力学及其抗拉强度理论的研究热点,认为对非饱和土合理统一的"吸力"认识仍然是非饱和土抗拉张特性研究的关键。然后,从岩土破坏模式角度,总结了岩土拉剪耦合破坏规律的8类破坏模式,分析了土体在此研究领域的现状,最后阐明了土体尤其是非饱和土的抗拉张力学特性研究现状的5个特点,展望了土体抗拉张力学特性新的重要研究方向。

Advances in Research on the Mechanical Behavior of the Tensile Strength of Soils

In conventional soil mechanics, soils usually do not act as tensile materials owing to their very small tensile strength, and therefore the tensile strength is always neglected. As a result, the soils’ tensile strength theory is far behind the shear strength theory. Actually, the tensile behavior of soils plays a very important role in the process of soils’ deformation and failure. In this paper, the development process and development characteristics of the soils’ mechanical behavior of tensile strength were summarized, and the new advances in the tests of tensile strength were introduced. Then, the latest development and research focus of the tensile strength for unsaturated soils were presented. Reasonable and unified acquaintance in suction of unsaturated soils was considered as the key to the tensile behavior of unsaturated soils. From the angle of failure mode of rock and soil, eight types of failure modes of rock and soil were summarized in the laws of tensile joint shear coupling failure, and the current research situation in this field was illustrated. At last, the problems existing in the research on the tensile behavior of soils, especially the unsaturated soils, were pointed out, and the directions of further research were given.