Double-effect grouting method for reinforcing new dam body and old dam body combined surface of stone-laying dam in thickening mode

The invention discloses a double-effect grouting method for thickening and reinforcing a new dam body and an old dam body of a stone-laying dam. In the preparation step, grouting tools are prepared, and new and old dam bodies are prepared to be combined for grouting; the cleaning step is conducted, specifically, impurities on the original dam face are removed, and then the original dam face is cleaned; laying preparation is conducted, grout stopping pieces are arranged on the periphery of each area, and meanwhile a grout pipe and a grout outlet box are arranged in combination with the chiseled stone-laying joint; construction is carried out, grouting is carried out through a grouting pipe, a grout outlet box, an exhaust pipe and the like, and double-effect grouting is completed; and a site cleaning step: collecting redundant materials after grouting is completed, and returning the equipment. The common treatment method of the new and old dam body joint surface comprises the measures of interface anchor rod, c