Study On The Anchor Support And The Stabilty Of Consequent Bedding Rock Slope

Base on the project of consequent bedding rock slope in the high-speed railway from Changsha to Kunming,this paper relied on the key subject of the Ministry of Railways, which was the high mountain slope stability evaluation methods and engineering measures research (2010G018-B-1). In this paper, commercial finite element analysis software was used to simulate the bedding rock slope of the Changsha-Kunming line,which analyzed the stability of slope,failure mode and the deformation characteristics in each construction stage of excavation.The full-length adhesive anchor was adopted as the surpporting structures and the force of the anchor in each stage of excavation was studied. Additionally, design of anchor was optimized.The main research works and conclusions were as follows.(1) The stability of two failure modes of the bedding sliding and bending-fracturing of the bedding rock slope was studied, and formula to calculate slope safety factor of the bending-fracturing failure mode was brought forward.(2) Results calculated by FEM strength reduction show that the slope safety factor varied with the excavation, while the slope failure mode varied with different stage of excavation.(3)The deformation characteristics were studied in each construction stage of excavation. Because of the excavation unloading effect, stress of slope was redistributed. Therefore, upward vertical displacement dominated the slope displacement.(4)Anchor support significantly improved the stability of the slope.The tension distribution of most anchor was a single peak curve,and the tension peak point was near the weak interlayer. The essence of the anchor reinforcement was to partly transfered the stress from weak interlayer to the anchor.(5)The anchor length and the distance between anchors in the design figures were optimized, and optimized anchor tension distribution was more reasonable, which manifested that the slope stability was better after optimization, thus improved the the rationality of the anchor support.