Two lines intersection small radius, shallow earth covering and large longitudinal slope complicated linetype shield construction method

A construction method and technology of shallow covering soil, which can be used in earth drilling, infrastructure engineering, artificial islands, etc., and can solve problems such as shield slipping out of the platform, and power vehicles self-propelled.

Active Publication Date: 2008-05-21
CHINA RAILWAY NO 2 ENG GRP CO LTD
View PDF0 Cites 47 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In the process of shield tunneling construction in large longitudinal slope sections, dangers such as the power vehicle detaching from the vehicle and the shield slipping out of the platform are prone to occur.
From the existing engineering examples, there are two-line interchange excavation, small-radius curve excavation, large longitudinal slope excavation, shallow overburden excavation and other single-line and simple overpass shield tunneling construction methods, and there is no such method as two-line interchange small Literature reports on shield tunneling methods in the case of radius, shallow overburden, and complex line shape of large longitudinal slope

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
  • Two lines intersection small radius, shallow earth covering and large longitudinal slope complicated linetype shield construction method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0086] Using two-dimensional numerical simulation, two working conditions are simulated according to the different tunnel advancement sequences, namely "construct the upper tunnel first, then the lower tunnel" (condition 1) and "construct the lower tunnel first, then the upper tunnel" (condition 1). 2) In two sequences, calculate and analyze the displacement of the first tunnel and the change of the internal force of the structure caused by the shield construction of the later tunnel under the two working conditions.

[0087] The calculation range is taken as 40m from the two sides and the bottom surface to the nearest tunnel edge, and the upper side is taken to the ground. Displacement boundary conditions are adopted as the boundary conditions, the upper boundary is taken from the ground, which is a free surface, and both sides and bottom surfaces are subject to normal constraints. The elastic-plastic model is used for calculation, and the yield criterion adopts the Drucker-P...

Embodiment 2

[0091] The elastic foundation beam model is used to study the longitudinal force and deformation of the tunnel structure during shield tunnel construction in small radius curves, and determine the segment reinforcement rib scheme to strengthen the longitudinal stiffness of the tunnel.

[0092] According to the line parameters of the small-radius curve section, the minimum radius is selected for calculation. Since the segment links are connected by bolts, the longitudinal connection can be simulated as an elastic hinge, and the reduction in lining stiffness is considered. Considering different bolt strengths and tightening degrees, the reduction rates can be considered to be 0.3 and 0.5, respectively. The reinforcing ribs are located at 30m on the left and right of the curved section, and are formed by welding two channel steels with steel plates, and then connected with the reserved grouting holes of the segments with bolts, so as to connect the tunnel longitudinally to enhance...

Embodiment 3

[0113] Take the shield construction of a two-line overpass of an underground tunnel with small radius, shallow overburden, and large longitudinal slope as an example: there are complex lines with small radius curves, two-line overpass, shallow overburden, and large longitudinal slope at the same time in the overpass section of the project Type and compound proximity, where the minimum distance between the upper and lower sides of the interchange is 2.05m, the intersection angle is 19°, and the minimum radius is R=230m, which is the smallest curve radius of the current domestic subway shield tunnel. The shallowest covering soil in this section is only 1.91m. It is far lower than the standard requirement of 1D (shield tunnel diameter) covering soil thickness. The shield construction method of this project is as follows:

[0114] 1) Choose an earth pressure balance articulated shield machine equipped with 2 copying knives, over-excavation range of 100mm, Φ of 6340mm, jack stroke ...

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 a shield construction method for a two-line overpass with small radius, shallow covering soil and large longitudinal slope complex linear tunnel, which belongs to the technical field of tunnel construction. The construction method of the present invention includes the following steps: determining the advancing sequence of the two-line interchange, selecting a shield machine type, taking auxiliary strengthening measures for the ground surface, strata, and segments, shield advancing, axis control and construction monitoring, and shield tunneling. In the present invention, since the shield increases the hinged part, the sensitivity of the shield is increased, and the control of the axis of the tunnel is more convenient; a suitable reinforcement and pressure scheme, a segment typesetting method and a stiffening rib scheme are selected to make the outer arc of the segment broken. Cracks and segmental water seepage can be improved; and through high-frequency monitoring and information feedback, the shield propulsion parameters are strictly controlled. By taking the above measures, the deformation and displacement of the ground surface and the tunnel are effectively controlled, which effectively reduces the cost of tunnel construction and The complex influence of the post-construction tunnel ensures the smooth progress of the construction and the effective control of the tunnel deformation.

Description

technical field [0001] The invention relates to the technical field of tunnel construction, in particular to a shield tunnel construction method for a two-line interchange with small radius, shallow soil covering and large longitudinal slope complex line. Background technique [0002] The shield construction process will cause changes in the internal stress of the soil, change the strength of the soil structure, and cause the strata to move within a certain range around the tunnel. When the two-line tunnels are constructed close to each other, there will inevitably be complex mutual influences, especially the construction of the first tunnel will be affected by the construction of the subsequent tunnel; moreover, the successive construction of the tunnels will cause multiple disturbances and superimposed effects on the stratum, which will easily cause the surface to subside Overrun. If there is a compound line pattern of small radius, large longitudinal slope, and shallow o...

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
Patent Type & Authority Applications(China)
IPC IPC(8): E21D9/00E21D9/093E02D29/045E21D11/04
Inventor 李林崔学忠陈强
Owner CHINA RAILWAY NO 2 ENG GRP CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap