Open-type TBM expanding excavation head falling prevention method

Abstract

The invention discloses an open-type TBM expanding excavation head falling prevention method. The open-type TBM expanding excavation head falling prevention method comprises the following steps that (1), expanding excavation is carried out; (2), accumulated slag at the arch bottom of the area behind a bottom shield is cleaned; (3), a cutterhead retreats; (4), arc-shaped steel plates are aligned and then placed behind the bottom shield; (5), a jacking device is placed below a main beam; (6), a jack is placed between the arc-shaped steel plates and the jacking device; (7), the jacking device is started, and the cutterhead and the bottom shield 2 are lifted; (8), the arc-shaped steel plates are jacked into the position below the bottom shield through a jack; and (9), the jack (9) is removed, and the jacking device is dismantled. The open-type TBM expanding excavation head falling prevention method has the advantages of being simple in structure, convenient to construct and operate, short in construction period and low in cost, by means of the open-type TBM expanding excavation head falling prevention method, the excavation axis of a TBM is kept, head falling tunneling during TBM expanding excavation is avoided, the excavation axis is guaranteed, the direction adjusting difficulty of a TBM main driver and a TBM driver is reduced, and the construction quality is improved; and meanwhile, the fatigue of a TBM mechanical structure caused by frequent and large-amplitude direction adjustment is delayed, and the equipment perfectness rate is increased.

Description

technical field [0001] The invention relates to a TBM construction method, in particular to an open-type TBM expansion and anti-heading method. Background technique [0002] At present, in TBM construction, when encountering poor geology of surrounding rock convergence or other special requirements, it is necessary to expand the excavation with a certain radius to increase the tunnel section. However, if the bottom shield is not replaced, the lower contour line of the TBM excavation and the outer contour of the bottom shield are not on the same arc surface, which will cause the nose of the TBM to continue to dig downwards, making it difficult to adjust the direction, and the course will gradually deviate from the original Design course, excavation direction deviation will become larger and larger, resulting in serious tunnel construction quality accidents. Contents of the invention [0003] The purpose of the present invention is to provide a method for reducing the error...

AI Technical Summary

Problems solved by technology

However, if the bottom shield is not replaced, the lower contour line of the TBM excavation and the outer contour of the bottom shield are not on the same arc surface, which will cause the nose of the TBM to continue to dig downwards, making it difficult to adjust the direction, and the course will gradually deviate from the original Deviations in design heading and excavation direction will become larger and larger, resulting in serious tunnel construction quality accidents

Images