Construction method for shock-absorbing blasting of underground space in urban area

Abstract

The invention discloses a construction method for shock-absorbing blasting of an underground space in an urban area, belongs to the technical field of foundation pit excavation engineering, and adopts three different construction methods for a whole blasting area by considering factors such as surrounding environment and topographic conditions. According to the first construction mode, a static crushing method is adopted for construction, and blasting areas within the range of 30 m away from a residential building and 3 m away from an enclosure structure and stand columns are constructed; according to the second construction mode, the blasting depth is smaller than 5 m, and shallow hole loosening is adopted for controlling blasting construction in the area where the section is trimmed and the bottom root is treated; and according to the third construction mode, deep hole weak loosening is adopted for controlling blasting construction in an area with the blasting depth larger than 5 m, before foundation pit excavation blasting, grooves are formed in the periphery, an enclosure structure is manufactured, the grooving depth is larger than the foundation pit depth, blasting construction is facilitated, cover-excavation top-down construction is adopted for urban area underground space excavation, the whole underground space structure is divided into four layers, a digital electronic detonator detonating network is adopted as the detonating network, safe and punctual detonating is guaranteed, and the ideal effect is achieved.

Description

technical field [0001] The invention relates to the technical field of foundation pit excavation engineering, in particular to a construction method for shock-absorbing blasting in an urban underground space. Background technique [0002] With the rapid development of economicalization and urbanization in our country, urban land use is becoming more and more tense, leading to more and more projects for the development and utilization of underground space. However, the development and utilization of underground space often involves excavation of foundation pits. In the central area of ​​the city, there are buildings and structures around large foundation pits. The excavation of foundation pits releases the stress of the ground, which causes the deformation of surrounding buildings and structures. As a means of excavating rocky foundation pits, blasting will cause blasting vibration damage to the foundation pit itself and surrounding structures during excavation of rocky found...

AI Technical Summary

Problems solved by technology

Among them, the differential blasting technology has certain advantages in cost control and efficiency improvement, but due to the current millisecond delay detonator time control accuracy is not high, and the inherent dispersion of the differential delay time is too large, so that the shock-absorbing blasting cannot achieve the ideal effect; while other methods can meet the requirements of safe production, but will cause a large increase in construction costs and a sharp decrease in construction efficiency

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