The invention discloses a construction process for a line-out shaft under conditions of rock
mass crushing, which belongs to the technical field of water conservancy and
hydropower construction engineering, and comprises the following steps: S1, preparation before construction: including arranging temporary construction projects on site according to the actual construction requirements of the line-out shaft, conducting
safety education and training for relevant personnel, and performing basic treatment on the bottom of the existing shaft; S2, construction of a geological drilling rig
pilot hole; S3, backfilling and supporting the excavated part of the existing shaft; S4, construction of a raise drilling rig
pilot hole; S5, construction of a shaft boring
machine pilot hole; S6, dismantling of the shaft boring
machine and the
wellhead system; S7, excavation, support and lining of the entire cross-section of the
wellhead locking section, and gradually completing the construction of the line-out shaft. By adopting a timely support method of excavating and supporting one layer at a time during the construction process and by timely support after excavation, the relatively short self-stabilization time of the surrounding rock under the condition of rock
mass crushing is effectively utilized, and large-scale deformation and damage that may occur during the construction of the line-out shaft is avoided.