Abstract:Deformation prediction and risk control of open-pit mining slope have the positive significance for construction guidance. Taking the slag dump slope of a quarry in Zengtian Expressway as a research project case, aiming at the water seepage of subgrade section, the hydraulic connection between mine pit and groundwater is analyzed, and the parameters of rock and soil mass are obtained by large-scale in-situ testing, and the sliding surface is calculated and analyzed. A reinforcement scheme of using anti-slide piles and anchor cables for the lower slope after earthwork clearanc and load reduction of slope, as well as an original anti-slide pile and anchor cable reinforcement scheme, are proposed. The slope waterproofing is achieved by setting up a water interception ditch on the slope surface, and a plain concrete pile waterproofing wall constructed by rotary drilling and interlocking technology and a drainage tunnel constructed by pipe jacking method are used in the subgrade section. Combined with the PLAXIS numerical simulation, the control effect of the two schemes of step-by-step construction calculation on the deformation safety of the slope body is evaluated. Combined with the comparison of monitoring profile data, the safety and construction economic superiority of the earthwork clearance and load reduction scheme are obtained. The design and research results of the project have achieved the good effects, and at the same time, the construction safety situation can be more accurately grasped.
