结构性黄土的双曲线强度公式及其破坏应力修正

抗剪和抗拉强度是结构性土体力学特性的两个方面。通过试验研究了结构性黄土原状土和重塑土的抗拉和抗剪强度。结合抗拉和抗剪强度的试验结果，建立了适用于结构性黄土的双曲线强度公式，进一步研究了相应的破坏应力的修正算法，并将应力比结构性参数引入到结构性黄土的双曲线强度公式中。研究结果表明，建立的结构性黄土双曲线强度可以克服在Mohr-Coulomb强度理论中夸大了的土体抗拉强度缺陷，可为结构性黄土地区的工程灾害评价提供更加切合实际的强度理论。

A hyperbola strength formula of structural loess and its modifying algorithm under failure stress state

Shear and tensile strengths are two aspects of the mechanical properties of structural soil. The strength of the structural intact loess and remolded loess are analyzed through two kinds of tests, which are namely the tensile strength test and the conventional triaxial shear strength test. The hyperbola strength formula of structural intact loess and remolded loess are determined by combining the test results of tensile and shear strength. The algorithms of tensile-failure stress state, tensile-shear stress state and compression-shear stress state are further investigated by modifying the corresponding failure stress according to the nonlinear strength. The structural parameter of stress ratio and the structure property are introduced into the developed hyperbola strength theory of structural loess. The results show that the established hyperbola strength formula of structured loess effectively overcomes the defect of exaggerated tensile strength based on the Mohr-Coulomb strength theory. It provides a practical strength theory which can evaluate the engineering disasters in structural loess area.