A kind of shield machine tail shield water-tight structure
Technical field
The utility model is between a kind of shield driving tail shield housing and the pipe sheet assembling moulding tunnel, and isolated underground water enters the tail shield water-tight structure in the tunnel, relates to the waterproof safety device technique field of shield tunnel construction.
Background technology
Shield excavation machine and coupling part, tunnel in the work progress, waterproof measure mainly is: be provided with the wire brush waterproof sealing between tail shield and the moulding tunnel, its hermetically-sealed construction through the special-purpose seal grease of pressure injection, forms the waterproof sealing system by wire brush one.Utilization structure is that 3~4 circle steel wire sealing brushes are installed in the tail shield the most widely.In construction because factors such as structures, installation, use, under the effect of synchronous grouting and muddy water circulatory system pressure, cement mortar can enter in the steel wire sealing brush, cement mortar is fixed to cause the steel wire sealing brush in the tail shield to damage, cause seal failure, cause tail shield water burst to gush sand, equipment and serious consequence such as flooded.Being no more than 300-500m general application life tail shield sealing system will occur and damage and leak, change to handle and to carry out the stratum consolidation improvement, difficulty is big, risk is high, long expense of implementation cycle is high, cause safety, duration, cost equivalent risk to construction, can not satisfy the requirement of modern safety construction.
The utility model content
The purpose of this utility model be design a kind of be used for tail shield sealing have improve steel wire sealing brush application life, water resistance height, abrasion resistance good, be convenient for changing, security risk is little, simple in structure, be convenient to process, cost is low, easy enforcement is changed shield machine tail shield water-tight structure.
The utility model is the afterbody at 3~4 circle steel wire sealing brushes 1, together emergent gas-flow closure circle 2 is installed with rubber cover sealing ring 3.
Specifically as shown in Figure 1, first welded and installed 3~4 circle steel wire sealing brushes 1 in the tail shield, the gas-flow closure circle 2 of will meeting an urgent need again is bonded on the tail shield housing, with bolt and pressing plate rubber is overlapped the afterbody that sealing ring 3 is fastened on tail shield housing at last.
Wherein:
Emergent gas-flow closure circle 2 is mainly used in after steel wire sealing brush 1 damages, when percolating water appears in the tail shield or during the replacing of tail shield steel wire sealing brush 1 needs, by inflation in emergent gas-flow closure circle 2 it is expanded the extruding sealing of the space between tail shield housing and the pipe sheet assembling moulding tunnel, play the effect of water-tight, the method sealing that need not to improve by geology is again handled, and has convenient fast and safely change steel wire sealing brush 1 or the processing of emergent tail shield sealing; Described emergent gas-flow closure circle 2 is made by rubber, and inflation is pressed and is 0.6-0.8Mpa when shield tail bad seals big percolating water occurs or changes sealing;
Rubber cover sealing ring 3 is mainly used in and prevents that muddy water or cement mortar from entering in the steel wire sealing brush 1, plays protection steel wire sealing brush 1 and increases the service life, and prevents to play that seal grease is excessive causes waste.
The utility model water resistance height, abrasion resistance be good, be convenient for changing, security risk is little, simple in structure, be convenient to processing, low, the easy enforcement of cost is changed.
Description of drawings
Fig. 1 tail shield water-tight structure chart
Fig. 2 pneumatic rubber seal loop graph of meeting an urgent need
Fig. 3 rubber cover sealing loop graph
Wherein the emergent gas-flow closure circle of 2-is brushed in the sealing of 1-steel wire
3-rubber cover sealing ring 4-shield driving tail shield
The specific embodiment
Embodiment. this example is the test construction that passes through in transfering natural gas from the west to the east natural gas line Jiujiang in the shield tunnel engineering of the Changjiang river.This length of tunnel 2580m, internal diameter 3080mm, the tunnel passes through gravel layer 1870m, flour sand layer 710m, maximum hydraulic pressure 0.43Mpa.Tail shield water-tight structure as shown in Figure 1.First welded and installed 3~4 circle steel wire sealing brushes 1 in the tail shield, the gas-flow closure circle 2 of will meeting an urgent need again is bonded on the tail shield housing, with bolt and pressing plate rubber is overlapped the afterbody that sealing ring 3 is fastened on tail shield housing at last.
Emergent gas-flow closure circle 2 is inflated to 0.7Mpa shutoff underground water when shield tail bad seals big percolating water occurs or changes sealing.
Pass through in the Yangtze River Tunnel construction in this project, tail shield seal leak water does not take place, brush 1 except normal wear until the sealing of tunnel holing through steel wire, emergent gas-flow closure circle 2, rubber cover sealing ring 3 all stand intact, do not find that muddy water and cement mortar enter in the tail shield steel wire sealing brush 1, have played good water-tight effect.
Test by this embodiment; this tail shield water-tight structure; effectively played the effect of protection tail shield steel wire sealing brush; prevent entering of muddy water and cement mortar; prolonged the application life of tail shield steel wire sealing brush; prevent that shield excavation machine from gushing the generation of sand accident at tunneling process tail shield seal leak water and water burst, reduced construction safety risk and shortened the duration.