地质力学模型试验在高边坡研究中的应用

应用地质力学模型试验技术研究岩体边坡的稳定问题,尚属需要进一步开拓的领域。三峡双线5级船闸开挖后,两侧均形成高边坡。边坡岩体为花岗岩;岩体中存在有断层和裂隙,并受高达5MPa以上的地应力作用。 国家“七五”科技攻关要求用地质力学模型试验技术研究其边坡的稳定。首先进行一个平面地质力学模型试验。并且结合平面模型进行平面弹塑性有限元分析,最后进行三维地质力学模型试验。试验成果分析认为:三方面的成果具有较好的可比性;三维模型相似模拟较全面;用逐级释放反荷载的方法模拟逐步开挖的地应力释放过程,通过实验验证是可行的。

Application of Geomechanical Model Tests to the Study of High Slopes

The application of the geomechanical model test technigue to the study of stubility problems of rock slope remains as yet a domain to be expanded. After the double-line and 5-stage lock of the Three Gorges Project being excavated, High slopes will be formed on its two sides. The rock of the slopes is composed of granite. In it there are faults and fissures. Moreover, the rock mass is subjected to a ground stress up to 5 MPa.The key scientific problem tackling programme included in the 7th Five-Year Plan sets forth re quirement to study the stability of the slope with the geomechanical model test techniques. The study in eludes: a 2-D geomechanical model test a 2-D elastic and plastic finite element analysis and a 3-D ge omechanical model test. Analysis of the test results shows that there is good comparability for the re suits from the three methods. The similarity of the 3-D model is better. It is feasible to simulate re lease process of geostress during step excavation using the method of stepwise releasing reverse load.