The bank slope stability evaluation of Jiagai River Bridge in Zhijin-Bijie Railway

Research purposes: In recent years, the role of bank slope stability evaluation in alpine valley region is more and more important to the determine of route scheme with the large number of the mountain railway construction. This paper is intended to determine the bridge span which is reasonable and economical by the analysis of regional engineering geological condition, bank slope stability and bank stability angle of Jiagai River Bridge in Zhijin-Bijie Railway, to provide the basis for the design of the bridge span. Research conclusions: The conclusions can be drawn through the comprehensive analysis of engineering geological conditions of Jiagai River Bridge site. (1) The area from the fourth stress-release crack to river cliff is unstable region, which can not place bridge pier. (2) The north bank slope of Jiagai River is stable and the south has stress-release crack, the stability of the slope angle is 65°. (3) The bridge main span is determined as 192 m, and the stress-release crack were sealed with grouting. (4) Canyon area line should select the region which has open terrain, slope stability and rock mass integrity. Bank slope stability evaluation should be carried out. The slope angle should be confirmed and the pier foundation should be placed below the bank slope stability line within a certain depth. (5) This paper can be used as a research reference for bridge site selection and bank slope stability evaluation in alpine valley region.