Controlled blasting and protecting method for major bridge foundation on two sides of high and steep gorge in scenic spot

The invention discloses a controlled blasting and protecting method for a major bridge foundation on the two sides of a high and steep gorge in a scenic spot. The controlled blasting and protecting method comprises the following steps that railings are arranged on the slope surface and in a valley below a blasting position of a the gorge for protection; a protective shed is arranged above a river; a protective channel is arranged at a tunnel exit; a side slope portion which is located above a major bridge foundation pit top surface platform and is in the shape of an oblique cone is blasted, the side slope portion is divided into a first blasting area and a second blasting area in sequence from top to bottom, the first blasting area and the second blasting area are blasted layer by layer from top to bottom, residue removal is conducted after blasting, and then the major bridge foundation pit top surface platform is obtained; and deep foundation pit basic rock layered blasting excavation is conducted on the major bridge foundation pit top surface platform, the rock mass on the blasting portion is covered with covering materials during blasting, supports are arranged on the pit wall after residues generated when each layer is blasted are removed, and construction is completed after the designed elevation is reached through excavation. According to the controlled blasting and protecting method, a three-dimensional multi-component protecting system is designed and established, any influences on the scenic spot in the blasting construction process are avoided, and a new idea of converting passive protection into active protection is provided.