Adjustable internal mold suitable for large-dip-angle box-type arch bridge

The invention provides an adjustable internal mold suitable for a large-dip-angle box-type arch bridge. The adjustable internal mold comprises an internal mold plate system, a hydraulic adjusting system, an automatic walking system, a deviation rectifying system and a control system. The inner formwork system comprises a heavy frame and a plurality of lug plates, an upper formwork, a lower formwork, a left formwork, a right formwork and four corner formworks are arranged on the periphery of the heavy frame, the free end of each side formwork split body and the free end of each corner formwork split body are each provided with a hinged connecting end, and the hydraulic adjusting system comprises hydraulic cylinders installed on the lug plates respectively. And the hydraulic cylinders are used for controlling the folding and unfolding of the corresponding templates. The automatic walking system comprises a displacement guide rail, hydraulic jacks are arranged in one-way clamping grooves in the two sides of the