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黄土高原北部的黄土由于含砂量高,广泛发育一种既不同于黄土滑坡、又不同于黄土崩塌的独立地质灾害类型——黄土滑塌。由于砂黄土的弱胶结性使得黄土滑塌呈现出某些不同于典型黄土滑坡的特点。从分布区域上看,它位于黄土高原的Ⅰ带,即砂黄土带;从发育的典型地质环境看,受制于当地特殊的土地资源和居住条件;从风险特征看,有“坍窑不坍掌”的特点;从诱发因素看,是降雨、冻融、冻胀、人工开挖等各种因素的综合作用。关于其变形破坏机制,不同的学者提出了不同的见解,有先塌后滑式、先滑后塌式、中部向两头延伸式和整体错落式,最新的研究表明其符合下部剪切破坏上部拉张倒塌模式,至于其微观机理方面的研究还很少。今后的研究应进一步查明诱发因素,总结该类滑坡变形破坏特征,综合运用数值和物理模拟手段,建立不同诱发因素影响下的地质力学模型,基于应力一应变关系,定量分析黄土滑塌的变形破坏机制,阐明其微观机理。
Due to the high sand content, loess in the northern part of the Loess Plateau has developed a kind of independent geological disaster, loess landslide, that is different from loess landslides and loess landslides. Due to the weak cementing of sandy loess, loess slides show some characteristics different from typical loess landslides. From the distribution point of view, it is located in the Loess Plateau Ⅰ belt, namely the loess plateau; from the development of the typical geological environment, subject to the local special land resources and living conditions; from the risk characteristics of view, there is Palm "features; from the trigger factor, it is rainfall, freezing and thawing, frost heave, artificial excavation and other factors of the combined effect. Different scholars have put forward different opinions on the mechanism of deformation and failure. The first one is slippery, the first slippery and the second slippery, while the middle one is two-headed and the whole is scattered. The latest research shows that it conforms to the lower part of the upper part of the shear failure Zhang collapse mode, as for its micro-mechanism research is still very small. The future research should further identify the inducing factors and summarize the deformation and failure characteristics of such landslides. The numerical simulation and physical simulation methods are used to establish the geomechanical model under the influence of different inducing factors. Based on the stress-strain relationship, the deformation of loess landslides Destroy the mechanism to clarify its micro-mechanism.