The High Slope Stable Evaluation Of The DaDu River Bridge Site

The Dadu River bridge is the most important building in the rebuild project of the provincial road S211 line, which located in the Dadu River main stream, being 450 m from Jinyang River downstream, and being 1.5 km from Changheba Hydropower Station. The bridge type is 3-span prestressed concrete continuous rigid frame, the length of the bridge is 406m, the Deck elevation is 1714m, and the maximum of the pier is 115.965m.The valley slope is steep in the bridge site district, which consists of the mixed rock. It's joint fracture developed, and the geological role is strongly, in addition, the bridge site is located in a high seismic intensity. Water level will significantly uplift after the Changheba Hydropower Station is completed and filled with water, and the slope stability problem is more pronounced in the district of bridge site. At the same time, there are strict requirements of the foundation deformation. Therfore, the foundation deformation of slope in the bridge site is an important technical problem to engineering design.The paper elucidated the structure and its distribution law of the rock slope, and establishing the deformation damage mechanisms and the evolution model of the rock slope on the basis of the investigation of the geological environment. Three methods are used: geological analysis and judgement, limit equilibrium analysis and numerical simulation analysis. On the basis of physical and mechanical tests, we do analyse, calculate and evaluate on the slope overall and partial cross-strait system, identifying the reservoir local area slope instability blocks' scale and exposed scope. Based on the above analysis, we have a comprehensive knowledge and understanding on the reservoir slope, and ultimately suggest an optimization advice to support pattern.Through research and analysis, this paper obtained that reservoir rock slope's deformation mechanism mainly includes planar slippage-rip, ladder-type slip-rip dumpage-rip and wedge slippage and deposit slippage. According to the engineering geological conditions of the bridge site slope, with the current exposed slope deformation and damage signs, we do the mechanism of deformation and failure mode analysis, on the slope natural bridge in cross-strait and excavation slope and suggest the potential instabile failure mode of the slope and the border, zoning and checking. With the help of the bridge load and reservoir water, we do further analysis and study on the base site of the bridge, checking the stability of its role in the condition. Finally, we contrapose the stability analysis on the bridge cross-strait slope, suggesting the programme advise on the support of the possible instabile area of the cross-strait locale slope.