A controlled blasting and protection method for bridge foundations on both sides of high and steep canyons in scenic spots

Abstract

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.

Description

Technical field [0001] The invention is used in the technical field of bridge construction, and particularly relates to a method for controlled blasting and protection of bridge foundations on both sides of high and steep gorges in scenic spots. Background technique [0002] In the construction of the bridge across the Grand Canyon, the main span of the bridge crosses the rafting area of ​​the Grand Canyon. Both sides are high and steep walls with inverted "V"-shaped ridges. The rock and soil distribution mainly includes swelling red clay, gravel soil, and white clouds. Limestone is interspersed with sand and shale layers, the karst body is weakly developed, and the vegetation on the mountain surface is lush. The Grand Canyon Scenic Area is a national 4A-level scenic spot. There are more than 1,000 drifters per day during the peak rafting season. The construction of the main bridge of the bridge needs to cross the core area of ​​the scenic area. The area mainly includes drifting ...

AI Technical Summary

Problems solved by technology

[0004] 1) The construction blasting area is located on the steep slopes on both sides of the canyon, the construction site is narrow, and the lower part is a national key tourist area, so large-scale blasting construction is not allowed;

Images