Method for constructing tunnel by finishing full section curtain grouting from upper-half section

Abstract

The invention relates to the field of tunnel construction, in particular to a method for constructing a tunnel by finishing full section curtain grouting from an upper-half section, which solves the problems of long construction period, difficult construction, high construction safety risk and the like during full section curtain grouting construction of a complex geological section. The method comprises the following steps of: firstly, excavating the upper-half section, and strengthening the support of a tunnel face; secondly, constructing a temporary inverted arch and a grout-stopping wall of the upper-half section; thirdly, excavating the lower-half section in place, and strengthening the support of the tunnel face; fourthly, constructing a grout-stopping wall of the lower-half section; fifthly, forming grouting holes on the upper-half section, wherein the maximum elevation angle alpha is between 25 and 45 degrees, the maximum depression angle beta is between 30 and 70 degrees, andthe longitudinal strengthening length is between 15 and 30 m; sixth, performing grouting operation; seventh, constructing a large-scale lead pipe roof; eighth, excavating a grout-stopping wall; ninth, excavating a tunnel trunk; and finally, continuously cycling by taking an area of 15 to 30 m as a grouting strengthening cycling section to realize the construction of the tunnel by curtain groutingfrom the upper-half section. The method can greatly reduce the construction difficulty, shorten the construction period, and ensure the construction quality, and the construction is safe, quick and economic, so the method can be widely used in the field of tunnel construction.

Description

technical field [0001] The invention relates to the field of tunnel construction, in particular to a construction method for a full-section curtain grouting tunnel with an upper half section completed. Background technique [0002] Under the guidance of the "leap-forward" development strategy of railways, my country's railway engineering has made great progress. At the same time, as the speed requirements are getting higher and higher, the construction line is severely restricted, and a large number of tunnel projects pass through geologically complex areas. Under the condition of ensuring safety, the construction method with the least investment and the fastest construction progress is particularly important. In areas with particularly complex geology, curtain grouting has the advantages of less investment, easy operation, low energy consumption, construction safety and fast construction progress compared with other full-section reinforcement construction methods. [0003]...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the problems of long construction period, high construction difficulty and unsafe construction in the existing full-section curtain grouting construction in complex geological sections, the present invention provides a construction method for the upper half section of the full-section curtain grouting tunnel

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