Dismantling method for concrete rigid frame arch bridge

The invention discloses a dismantling method for a concrete rigid frame arch bridge. The construction method comprises the following steps that construction preparation is conducted, specifically, a reasonable dismantling sequence is determined, cutting equipment is selected and is in place, buoyancy tank supports are arranged and checked, and lifting tools are checked; block dividing and paying off are conducted, specifically, according to the dismantling sequence, to-be-dismantled structures are subjected to block dividing and arranging; auxiliary arrangement such as handrails and micro-bending plates are dismantled; cutting machines and the buoyancy tank supports are mounted; primary and secondary arch ribs and connecting systems are cut and hoisted; a sunk well foundation dismantling protection structure is constructed; sunk well foundation block diving cutting and hoisting are conducted; and foundation pit backfill, river cross section recovery and protection structure dismantling are conducted. According to the dismantling method, by setting up the scientific dismantling sequence and using reasonable dismantling equipment, the disadvantages that as for a traditional dismantling method, the potential safety hazard is large, dismantling noise and dust are more, secondary cleaning pollution is serious, and the difficulty is large are avoided, and thus dismantling construction can be safely and efficiently carried out in an environmentally friendly mode.