Process for excavating and constructing soft rock tunnels

Abstract

The invention discloses a process for excavating and constructing soft rock tunnels. Each constructed soft rock tunnel comprises two tunnel portal sections and a tunnel trunk section. Each tunnel trunk section is arranged between the two corresponding tunnel portal sections in a connected manner, surrounding rock level of two tunnel portals of each constructed soft rock tunnel is V level, surrounding rock level of each tunnel trunk section is IV level, and entrances and exits of the constructed soft rock tunnels simultaneously start to be constructed and are constructed in opposite directions. The process includes constructing procedures of firstly, determining methods for excavating the tunnel trunk sections, to be more specific, simulating excavating and constructing procedures by the aid of tunnel excavating and constructing simulation software, and determining the methods for excavating and constructing the tunnel trunk sections according to simulation results; secondly, excavating and constructing the tunnels, to be more specific, dividing each soft rock tunnel to be constructed into a plurality of sections from the rear of the corresponding tunnel portal to the front and starting to excavate and construct the multiple sections. The tunnel trunk sections are excavated in the excavating and constructing procedures by the aid of full-section techniques. The process has the advantages of simple steps, reasonable design, convenience in construction, good service effects, safe constructing procedures and capabilities of easily and conveniently completing the soft rock tunnel excavating and constructing procedures and guaranteeing the construction periods.

Description

technical field [0001] The invention belongs to the technical field of tunnel excavation construction, and in particular relates to a soft rock tunnel excavation construction technology. Background technique [0002] At present, the construction period of various projects is relatively tight, and the reasonable construction period has been compressed, ranging from a few months to shortening the construction period to half a year or even a year. For extra-long tunnels, without auxiliary pilot pits, the construction is close to the two working faces of the entrance and exit, and the construction period is extremely tight, especially in the case of poor surrounding rock conditions and frequent collapses, the construction progress is difficult. For example, during the excavation and construction of an extra-long soft rock tunnel with a length of more than 5km, since the construction of soft rock tunnels focuses on safety, but due to the guarantee of the construction period, the ...

AI Technical Summary

Problems solved by technology

Speeding up the excavation mainly adopts increasing the circular footage, which brings about safety hazards of excessive excavation footage in soft rock; speeding up the support construction may lead to a decline in the quality of the support, and the quantity cannot meet the design requirements, which will also cause a relatively large safety hazard

Therefore, the rapid construction technology for weak surrounding rocks of extra-long highway tunnels at home and abroad is still in the stage of exploration and research, and there is no breakthrough in the construction of weak rock formations, and there is no mature and complete set of construction experience

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