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利用数值模拟以及地应力实测资料,研究了高地应力区河谷应力场的分布特征,发现对于无卸荷带的均质弹性边坡,从坡表到坡内可以划分为应力降低区(σ1<γh)、应力平稳区(σ1=γh)2个区;对于存在卸荷带的边坡,从坡表到坡内可以划分为3个区:应力降低区(σ1<γh)、应力升高区(σ1>γh)、应力平稳区(σ1=γh)。卸荷带的存在是最大主应力从坡表至坡内出现3个带的本质原因。高地应力区边坡由于构造应力场的存在,使得边坡应力集中的水平明显提高,集中的范围明显变大,边坡常常存在较宽卸荷带,因此,高地应力地区高陡边坡的应力场也可以大致划分为应力降低区、应力升高区、应力平稳区3个带。但一些高地应力地区边坡内部发育深部卸荷裂缝,其应力集中区向坡体内部转移,应力降低区内的应力出现波动变化,深部裂缝存在部位应力明显降低。
The distribution characteristics of the stress field in the valley of the high ground stress region are studied by using the numerical simulation and the in-situ stress data. It is found that for the homogeneous elastic slope without the unloading belt, the slope from the slope table to the slope can be divided into the stress reduction area (σ1 <γh (Σ1 = γh). For the slope with unloading belt, there are three zones from the slope table to the slope: stress reduction zone (σ1 <γh), stress increase zone ( σ1> γh), stress-stable region (σ1 = γh). The existence of the unloading belt is the essential reason that the maximum principal stress occurs in three bands from the slope table to the slope. Due to the existence of tectonic stress field in the high geostress zone, the level of stress concentration in the slope is obviously increased, and the concentration range is obviously larger. There is often a wide unloading zone in the slope. Therefore, the stress of the steep slope in the high geostress area The field can also be roughly divided into three zones: stress reduction zone, stress rise zone and stress smooth zone. However, in some high-stress areas, deep unloading cracks develop in the slope, and the stress concentration area shifts to the interior of the slope. The stress in the stress-reduced area fluctuates and the stress in the deep cracks decreases obviously.