Advanced grouting construction method for underground excavated tunnel

Abstract

The invention discloses an advanced grouting construction method for an underground excavated tunnel. The method comprises the steps of step I, dividing the section of the tunnel into a first upper pilot tunnel, a second upper pilot tunnel, a first lower pilot tunnel and a second lower pilot tunnel; step II, after pipe shed advance support, performing advanced grouting on the first upper pilot tunnel in the tunnel excavation direction, and excavating and supporting the first upper pilot tunnel; step III, performing grouting reinforcement on the to-be-excavated areas of the first lower pilot tunnel and the second upper pilot tunnel from the first upper pilot tunnel through the excavated and supported space of the first upper pilot tunnel; step IV, excavating and supporting the first lower pilot tunnel, performing grouting reinforcement on the to-be-excavated area of the second lower pilot tunnel from the first lower pilot tunnel through the excavated and supported space of the first lower pilot tunnel; step V, excavating and supporting the second upper pilot tunnel, and then excavating and supporting the second lower pilot tunnel; and step VI, repeating the step II, the step III, the step IV and the step V, and completing tunnel construction. The construction method can shorten the construction period, improve the grouting effect and reduce the construction cost.

Description

technical field [0001] The invention relates to the technical field of tunnel engineering, in particular to an advanced grouting construction method suitable for tunnels dug in shallowly buried soft geological sections. Background technique [0002] Due to the complex occurrence conditions and poor geological conditions of shallow tunnels, most of the surrounding tunnels are soft soil layers, and they are often affected by groundwater, which brings great safety hazards and unknown construction risks to tunnel construction. Because the deformation control of surrounding rock is very strict in tunnel construction; therefore, advance grouting reinforcement (support) is a very necessary and feasible safety measure during tunnel excavation. [0003] However, the traditional advanced grouting support is constructed by the CRD method (cross partition wall method). Since the entire section is grouted at the same time, to achieve the effect of advanced grouting, there are generally l...

AI Technical Summary

Problems solved by technology

[0003] However, the traditional advanced grouting support is constructed by the CRD method (cross partition wall method). Since the entire section is grouted at the same time, in order to achieve the effect of advanced grouting, there are generally long grouting distances, long grouting time, and grouting problems. The effect cannot be guaranteed, it is uneconomical, and it affects the construction progress and other shortcomings

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