A construction method using pilot holes for guiding and positioning and smooth blasting

Abstract

The invention relates to a construction method adopting guide positioning through a guide hole and smooth blasting. The construction method includes the steps that S1, a hole drilling blasting method is adopted for excavating a vertical shaft, an inclined shaft or a groove to the design elevation; S2, the four corners of the vertical shaft are excavated to form guide positioning holes, the drilled hole depth of the guide positioning holes reaches the design elevation; S3, the four positioning holes are connected, positioning control pre-cracking holes are distributed on a peripheral excavation line, and drilling to the design elevation is achieved at a time; S4, based on field engineering geology and rock conditions, the number of the drilled holes is appropriately increased, and the charging amount is adjusted; and S5, after vertical footage by 5 m, blasting excavation is paused, pouring of concrete is used for locking, after a tunnel is through, the vertical shaft is blast to penetrate a safety layer, and parallel slag discharging from the tunnel is achieved. The construction method has the beneficial effects that the construction quality is improved, the back break amount is reduced, and the stability of surrounding rock is good; the temporary support lining work amount can be reduced, and the construction cost is reduced; and the construction period can be accelerated.

Description

technical field [0001] The invention relates to a blasting construction method, in particular to a blasting construction method using pilot holes for guiding and positioning and smooth surface blasting. Background technique [0002] Drilling and blasting excavation technology is mainly used in blasting excavation projects of various vertical (inclined) wells, tunnels, rocks, etc. in transportation, water conservancy, industrial and civil construction, and civil defense. [0003] Due to the ever-changing engineering geological conditions and construction conditions, the selection of various parameters is based on the primary selection of parameters based on experience, and then determined through field tests. For example, blasthole diameter should consider blasthole utilization rate, drilling efficiency, rock stability and other factors. In the specific construction, there are often actual conditions such as uneven rock hardness, different degrees of weathering, and differen...