Blasting and cutting combined excavation construction method for large-span underground cavern of pumped storage power station

Abstract

The invention provides a blasting and cutting combined excavation construction method for a large-span underground cavern of a pumped storage power station, and relates to the technical field of underground cavern blasting and cutting construction. The construction method comprises the following steps that (1) presplitting blasting is conducted; (2) the middle part is subjected to bench blasting;(3) a side wall cutting hole is formed; (4) track arrangement is conducted; (5) wire saw cutting is conducted; (6) materials are taken from a foundation trench; and the blasting and cutting combined excavation construction method for the large-span underground cavern of the pumped storage power station is high in surrounding rock integrity and stability. The side walls are cut in a blasting-free mode, damage to the whole cavern rock stratum is small, especially disturbance to complex rock stratum areas or III-class and IV-class surrounding rocks is small, it is guaranteed that the surroundingrocks are not damaged by vibration, and the integrity and stability of the surrounding rocks are guaranteed.

Description

technical field [0001] The application relates to the technical field of blasting and cutting construction of underground caverns, in particular to a construction method of blasting and cutting combined with excavation of large-span underground caverns for pumped storage power stations. Background technique [0002] At present, the excavation of the underground caverns of the pumped storage power station still adopts the traditional mining method or the cutting method without blasting. figure 1 It is a schematic diagram of cavern blasting excavation in the prior art, such as figure 1 As shown, the traditional blasting excavation cannot be operated in a 24-hour cycle due to the management of detonators and explosives. The blasting vibration is large, which has a great impact on the integrity of the lower rock formation. During the excavation process, reinforcement and support are often added due to the impact of blasting vibration, and even the cavern collapses. The quality...

AI Technical Summary

Problems solved by technology

figure 1 It is a schematic diagram of cavern blasting excavation in the prior art, such as figure 1 As shown, traditional blasting excavation is restricted by the management of detonators and explosives and cannot be operated in a 24-hour cycle

The blasting vibration is large, which has a great impact on the integrity of the lower rock formation. During the excavation process, reinforcement and support are often added due to the impact of blasting vibration, and even the cavern collapses.

The quality of the excavation process is difficult to meet the design requirements

High safety risks, low construction efficiency, poor working environment, high investment of construction personnel and complicated construction organization, traditional blasting cannot guarantee the safety and quality of excavation

[0003] The construction technology of non-blasting cutting is greatly affected by geological factors, especially under the condition of high ground stress, the efficiency of non-blasting cutting combined with excavation is slow, which has a great impact on the construction period, and non-blasting cutting cannot guarantee the construction progress

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