Construction method for secondary lining at abrupt change section and dismantling method for temporary support of secondary lining at abrupt change section

Abstract

The construction method comprises the following steps: (1) after primary support construction of a tunnel is completed and stabilized, starting a secondary lining construction device to reach a specified construction position and then putting the secondary lining construction device in place; (2) after the second lining construction device is in place, a positioning device is started to enable the second lining construction device to be stable at the construction position, and then a second lining formwork system for jacking the second lining construction device is started; (3) a plurality of secondary lining template systems are adjusted in place; (4) concrete construction is conducted, and secondary lining construction at the abrupt change section is completed; (5) a temporary supporting structure of the second lining formwork system is started and contracted, namely, the second lining formwork system is removed, and a temporary support is dismantled; and the second lining construction device is moved, and the steps are repeated for construction of the next working section. According to the method, the safety and economical efficiency of secondary lining construction can be improved according to the situation that the section of the tunnel changes suddenly, countermeasures are provided for dangers possibly occurring when the temporary support is dismantled, and the safety and efficiency of the construction process are guaranteed.

Description

technical field [0001] The invention relates to the technical field of construction of tunnel engineering, in particular to a construction method for a secondary lining at a sudden change section and a method for dismantling its temporary support. Background technique [0002] In tunnel construction, due to the requirements of functional settings, the cross-section size of the tunnel is variable, especially in the case of subway tunnels that are often hundreds of meters long and have several to a dozen different sizes of cross-sections. There are two traditional construction methods for the secondary lining construction of such tunnels with short length but various cross-sections. In the first method, multiple trolleys will greatly increase the construction cost, and when the opening of the hole is a small section and the inside of the hole is a large section, the assembly and dismantling of the trolley must be constructed in the hole, which increases the construction diffic...

AI Technical Summary

Problems solved by technology

In the first method, multiple trolleys will greatly increase the construction cost, and when the hole is a small section and the inside of the cave is a large section, the assembly and disassembly of the trolley must be constructed in the cave, which increases the construction difficulty and construction period; while the second This method has the situation that the erection and dismantling of the full hall support requires a lot of work, and the assembly of small pieces of loose formwork requires high construction requirements and is difficult.

[0003] In addition, after the construction of the second lining is completed, the removal of the temporary support has a greater risk for the tunnel support. At the same time, the removal speed often restricts the construction progress. Therefore, the removal speed and engineering safety are two aspects that need to be considered during construction. The research on the demolition of temporary supports is mainly to verify the feasibility of the original design scheme, or to dynamically adjust the demolition scheme according to the monitoring data of surrounding rock and initial support in actual construction, but such methods often have lags and cannot be pre-determined. The problems that may be encountered are found out, and the removal efficiency of temporary supports cannot be effectively improved.

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