A vertical cup-shaped freezing reinforcement structure and method at the end of a shield tunnel

Abstract

The invention discloses a vertical cup type freezing reinforcement structure and method at the shield tunnel end. The vertical cup type freezing reinforcement structure is multiple rows of vertical freezing pipes which are distributed in a soil body outside a working well at the shield tunnel end and are distributed to be shaped like a Chinese character 'kou', horizontal freezing pipes are arranged on the lower portion of the soil body on which the vertical freezing pipes are distributed in the working well at the end, refrigerant media are circulated in the vertical freezing pipes and the horizontal freezing pipes, and therefore a vertical cup type frozen wall reinforcement body can be formed in the soil body outside the working well at the shield tunnel end. The reinforcement method comprises the steps of step 1, freezing designing; step 2, refrigerating system designing; step 3, drilling constructing; step 4, freezing constructing; step 5, slot wall breaking; step 6, freezing pipe removing; step 7, frost heave and thaw subsidence controlling. The vertical cup type freezing reinforcement structure and method at the shield tunnel end has the advantages that a strata reinforcement mode for the end of a soft soil area which is rich in a water sand layer is achieved, the problem that in the area, a conventional reinforcement mode is poor in reinforcement effect can be effectively solved, and it can be guaranteed that a shield tunneling machine smoothly breaks in and out a tunnel portal.

Description

technical field [0001] The invention relates to a structure and method for freezing and reinforcing the end of a shield tunnel, in particular to a vertical cup-shaped freezing and strengthening structure and method for the end of a shield tunnel. Background technique [0002] At present, the reinforcement of shield tunnel end is a key link in the construction of shield tunneling method, which has great construction risks. When the shield enters and exits the tunnel, the underground continuous wall in the tunnel area must be broken first, and all steel bars must be cut off. The time required for demolition of the cave door is very tight and the construction is difficult. After the portal is demolished, the strength and sealing of the reinforced body are very high. If the reinforcement effect is not good, the gap between the shield and the portal and the surface settlement will easily occur during the demolition of the portal, which will endanger the nearby underground pipeli...

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Problems solved by technology

[0003] The purpose of the present invention is to solve the problem that some reinforcement structures and methods are difficult to meet engineering requirements during the reinforcement process of shield tunnel ends in areas rich in water and sand layers, and often lead to serious water and sand leakage. Vertical Cup Type Freezing Reinforcement Structure and Method at Tunnel End

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