Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

In-hole treatment method for shield tunnel in liquefiable stratum

A technology of shield tunnel and treatment method, applied in tunnels, tunnel linings, underground chambers, etc., can solve the problems of tunnel collapse, reduced restraint effect, endangering the safety of structures, etc., to shorten the construction period and improve the liquefaction resistance. , The effect of reducing the project cost

Pending Publication Date: 2021-10-15
CHINA RAILWAY NO 17 BUREAU GRP +1
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, under the condition of earthquake liquefaction stratum, such underground structures are easily damaged by earthquakes, especially under the action of strong earthquakes, the confinement effect of the soil around the underground structure is reduced or lost, and the deformation of the soil around the underground structure will cause damage to the structure. The additional stress may be very large, resulting in earthquake damage to some weak links of the underground structure
At the same time, due to the mechanical vibration and disturbance during shield excavation, the stratum is prone to liquefaction, which may cause over-limit settlement of the ground and endanger the safety of surrounding buildings and structures; social influence

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • In-hole treatment method for shield tunnel in liquefiable stratum
  • In-hole treatment method for shield tunnel in liquefiable stratum
  • In-hole treatment method for shield tunnel in liquefiable stratum

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment approach 1

[0034] Specific implementation mode 1: This implementation mode records a treatment method in a liquefiable stratum shield tunnel, and the method is specifically:

[0035] Step 1: Synchronous grouting to replace pore water;

[0036] Step 2: Secondary grouting to cut off pore water;

[0037] Step 3: Anti-liquefaction treatment in the cave.

specific Embodiment approach 2

[0038] Embodiment 2: In the method for treating the inside of a liquefiable stratum shield tunnel described in Embodiment 1, in step 1, the specific operation of synchronous grouting to replace pore water is as follows:

[0039] The groundwater in the liquefiable formation is rich and has a large permeability coefficient. When the shield tail gap is formed, the precipitated pore water fills up rapidly, which makes grouting difficult, and the grout is diluted by pore water after entering the formation, and the performance of the grout is greatly affected, so grouting cannot be guaranteed fill effect.

[0040] Before the start of excavation of each ring shield, ball valves are installed in the reserved grouting holes of the capping block segment at the top of the third last ring of the shield tail (that is, the first ring out of the shield tail), and the reserved grouting holes are opened through steel brazing or electric drills , close the ball valve in time, and when the excav...

specific Embodiment approach 3

[0041] Specific implementation mode three: the treatment method in a liquefiable stratum shield tunnel described in specific implementation mode 1 or 2, in step 2, the specific operation of the secondary grouting to cut off pore water is as follows:

[0042] The formation of the water-proof hoop requires secondary grouting in the pre-embedded grouting holes of the 6 segments of the ring, from bottom to top, left and right alternately symmetrical grouting; after selecting the grouting hole position, put on the grouting unidirectional After the check valve, use an electric hammer to drill through the concrete protective layer of the hole, connect the tee, the cement slurry pipe and the water glass slurry pipe. When injecting double slurry, first inject the pure cement slurry for 1 minute, and then open the water glass valve. 1:1 mixed injection, the concentration of water glass itself should be increased from the initial 35°Be' to 40°Be' when the final hole is completed, and the ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses an in-hole treatment method for a shield tunnel in a liquefiable stratum, and belongs to the technical field of tunnel shield construction. The invention aims to solve the shield construction risk of the liquefiable stratum. The method comprises the following steps of synchronously grouting and replacing pore water; cutting off pore water through secondary grouting; and carrying out in-hole anti-liquefaction treatment. While the shield tail gap of the liquefiable stratum is prevented from being formed, separated-out pore water is used for diluting slurry, and the grouting filling effect is guaranteed; pore water is prevented from flowing and gathering along a formed tunnel, and synchronous grouting slurry which is not initially set is limited to longitudinally flow due to the gradient of the tunnel; and the anti-liquefaction capability of the shield tunnel is improved, the construction cost is reduced, and the construction period is shortened. Compared with a traditional method for conducting full-section reinforcement treatment on a liquefied soil layer from the ground through cement-soil mixing piles and high-pressure jet grouting piles, targeted local stratum treatment can be conducted under the condition that the ground does not meet the construction condition.

Description

technical field [0001] The invention belongs to the technical field of tunnel shield construction, and in particular relates to a method for treating the inside of a shield tunnel in a liquefiable stratum. Background technique [0002] With the rapid development of domestic urban rail transit construction, more and more subway projects inevitably need to pass through liquefied soil layers during the construction process due to the constraints of the overall planning of the line network, existing urban construction conditions, and overall control of project costs. Earthquake hazard monitoring and statistical data at home and abroad show that the damage caused by earthquake liquefaction to underground structures is much higher than that of ordinary sites, especially in high-intensity areas. With the continuous expansion of domestic subway construction scale in recent years, the earthquake resistance of underground structures has become an important topic in the research of urb...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): E21D11/40E21D9/06
CPCE21D11/40E21D9/06
Inventor 陈宏伟凌贤长孔祥勋唐亮
Owner CHINA RAILWAY NO 17 BUREAU GRP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com