Construction method for tunnel to pass through existing anti-slide pile

The invention discloses a construction method for a tunnel to penetrate through an existing anti-slide pile. The construction method comprises the steps that 1, displacement and tilt angle sensors are buried at measuring points of an existing anti-slide pile section; step 2, measuring and positioning the position of the slide-resistant pile in the hole; 3, the slide-resistant piles are cut off, and supports are erected; 4, concrete is sprayed for sealing after the supporting frame is erected; 5, slotting, finding out and cutting off the anchor cable; 6, steel arch frames are connected, so that arch frame supports form a closed loop; 7, monitoring internal and external settlement deformation of the hole; step 8, gradually breaking the slide-resistant piles at the lower part to the initial support bottom of the inverted arch; according to the method, the positions of the slide-resistant piles are found out by adopting a tunnel layered excavation method, the tunnel is effectively supported by utilizing the steel