Stability Evaluation And Optimal Design Of The Treatment Technologies For Shuang Yi Xiang Landslide

The sensitivity of factors affecting landslide stability and the idea of "Conceptual design" are used in existing landslide stability assessment method and the optimization design of the control projects separately. So the paper choose DaPoShang landslide located in Yibin, Sichuan province as research object. The landslide stability evaluation and the engineering design optimization are studied with the methods of extensive geological survey and exploration, numerical calculation and theoretical analysis. The results obtained are as follows:1.The analysis results using the geological datum shows that the stability of the landslide slope, and the safety factor cannot satisfy the requirement. Under the conditions of natural state and earthquake effect, the slope is in limit equilibrium or instability., If the landslide slip surface is full of water In rainy season, the slop is in basic stability or understable state. And by the acting of the slip surface water saturation and earthquake the slop is in instability.The landslide treatment must be taken.2. Influence factors of landslide stability such as the internal friction angle and cohesive force of the slip surface, seismic force, the density of sliding body, etc. are put forward based on the reserach results of the natural geological environment basic characteristics,the formation mechanism and the present situation and development trend of landslide stability, using orthogonal design method to analyze the sensitivity of these factors. Combined with the limit equilibrium analysis results, a reasonable evaluation about stability of the landslide is appraised.3. The optimization design of control project for the landslide is proposed with the idea of "Conceptual design". The treatment method is to introduce engineering practices such as surface drainage, Prestressed anchor-hold piles, and the detailed optimization design and numerical calculation are worked.4. The project has been completed in August 2000, and tested by the monitoring results and rainfall scouring many years, it is safe and stable now. It is proved that the stability evaluation and treatment methods is feasible. This project has been awarded the excellent project by Ministry of Land and Resources,Sichuan Provincial Committee of Land and Resources, Yibin city separately.