Anti-floating positioning support device and synchronous grouting method during shield segment assembly

Abstract

The present invention relates to the technical field of shield tunnel construction, and specifically to an anti-floating positioning support device and a grouting method during the assembly of shield segments. The temporary support device includes an integrated connection pedestal and a support spoke, one end of the support spoke is anchored and connected to the integrated connection pedestal, and a plurality of support spokes are arranged in an equidistant array along the outer circumference of the segment; the method includes the steps of installing a temporary support device, installing segments, synchronous grouting, jacking excavation, moving the temporary support device, and supplementary grouting, and the construction process is simple. The temporary support device can stabilize the position of the segment during the segment assembly and grouting process, avoid various floating effects, such as local floating of the segment, uneven grouting behind the wall, misaligned joints and misaligned platforms of the local assembly of the segment, and stress concentration, thereby improving the construction and assembly quality of the shield segment and the overall safety of the structure. The device and method are particularly suitable for occasions where the groundwater level is high and groundwater invades the excavated tunnel.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel construction, in particular to an anti-floating positioning support device and a synchronous grouting method during shield segment assembly. Background Art

[0002] With the rapid development of urban underground transportation, the progress of subway construction is accelerating, and the shield method is increasingly used in the construction of subway section tunnels. After the shield tail is assembled, there is a certain gap between the segment and the excavation limit, which needs to be filled by grouting behind the wall. However, when constructing subway tunnels in cities, large buoyancy often occurs in areas with abundant groundwater and the shield tail, causing the shield tail segment to float, resulting in uneven grouting layer behind the segment wall. The dislocation of the segment affects the quality of construction and assembly, causing local stress concentration in the segment, and unfavorable stress state, which cannot guarantee the overall safety of the structure. In addition, the uneven distribution of the grouting layer will also lead to differences in the values ​​of the formation resistance coefficient at different parts around the tunnel. The formation resistance coefficient has a greater impact on the internal force of the segment ring, especially the bending moment, which will further have an important impact on the structural design of the segment. Summary of the invention

[0003] The present invention aims to provide an anti-floating positioning support device and a synchronous grouting method during the assembly of shield segments. The temporary support device can stabilize the position of the segments during the assembly and grouting of the segments, avoid local floating of the segments caused by various floating effects, uneven grouting behind the wall, misaligned joints and misaligned platforms in local assembly of the segments, stress concentration and other problems, thereby improving the construction assembly quality of the shield segments and the overall safety of the structure.

[0004] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0005] The temporary support device for the anti-floating positioning of the shield segment disclosed in the present invention comprises an integrated connection pedestal and a plurality of support spokes, the front ends of the support spokes are anchored to the integrated connection pedestal, and the plurality of support spokes are arranged at equal intervals along the outer circumference of the segment.

[0006] Preferably, the integrated connection base is located on one side of the tube segment, the bottom surface of the supporting spokes is in contact with the outer arc surface of the tube segment, and the supporting spokes are freely protruded from the other side of the tube segment.

[0007] Preferably, there are 7 to 15 supporting spokes.

[0008] Preferably, the top surface and the bottom surface of the integrated connection base are both arc surfaces, the top surface is flush with the top surface of the supporting spokes, and the bottom surface is flush with the inner diameter surface of the pipe segment.

[0009] As a preferred embodiment, the supporting spokes are rectangular spokes, the cross-section of the rectangular spokes is rectangular, the center angle of the rectangular spokes relative to the pipe segment is 2°, and the center angle of the cross-section of the integrated connection pedestal is 45°~55°; the width of the integrated connection pedestal is 0.35~0.45m, and the length of the supporting spokes is 1.5~2 times the width of the pipe segment.

[0010] Furthermore, a row of rollers is provided on the top of the rectangular spokes, the rollers are arranged along the axial direction of the rectangular spokes, and the rolling direction of the rollers is the axial direction of the rectangular spokes. When the temporary support device is in use, the rollers are in contact with the excavation limit.

[0011] As another preferred embodiment, the supporting spokes are T-shaped spokes, the cross-section of the T-shaped spokes is T-shaped, and when the temporary supporting device is in use, the top surface of the T-shaped spokes is in contact with the excavation limit.

[0012] Furthermore, the integrated connection pedestal is provided with a connection device for connecting to a shield machine.

[0013] The present invention also discloses a grouting method using the temporary support device, comprising the following steps:

[0014] Step 1: Assemble the pipe segments and install the temporary positioning device on top of the pipe segments for the first time;

[0015] Step 2: Synchronously grout the gap between the segment and the excavation limit;

[0016] Step 3: The shield machine advances to excavate and drives the temporary support device forward, while performing supplementary grouting;

[0017] Step 4: Assemble the segments to the temporary positioning device installed on the top, and then repeat steps 2, 3, and 4.

[0018] Furthermore, the top of the supporting spoke is coated with lubricating oil.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. In shield tunnel construction, before grouting behind the wall, the temporary support device of the present invention can be used to stabilize the position of the segments during segment assembly and grouting, avoid various floating effects, such as local segment floating, uneven grouting behind the wall, misaligned joints and platforms in local segment assembly, and stress concentration, thereby improving the construction and assembly quality of the shield segments and the overall safety of the structure. It is particularly suitable for occasions where the groundwater level is high and groundwater invades the excavated tunnel.

[0021] 2. The rectangular cross-section support spokes with rollers are suitable for rock tunnels to reduce friction with the surrounding rock; the T-shaped cross-section support spokes without rollers are suitable for soil tunnels to increase the pressure between the spokes and the surrounding rock. The lubricating oil on the spokes ensures that the temporary support device can be smoothly separated from the pipe segment for the next ring construction.

[0022] 3. The integrated connection pedestal is connected to the shield machine through a connecting device. The shield tunneling and the movement of the pedestal are carried out in sequence to ensure the construction progress and reduce the construction cost.

[0023] 4. The present invention adopts the steps of installing temporary support devices, installing pipe segments, synchronous grouting, jacking excavation, moving temporary support devices, supplementary grouting, etc., and performs cyclic construction with simple process and can significantly improve the construction quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic structural diagram of Example 1;

[0025] Figure 2 yes Figure 1 Bottom view of

[0026] Figure 3 It is a schematic diagram of the structure of the integrated connection pedestal;

[0027] Figure 4 is a schematic structural diagram of Example 2;

[0028] Figure 5 It is a schematic diagram of the structure after the present invention is installed;

[0029] Figure 6 is a cross-sectional view of the present invention after installation;

[0030] In the figure: 1-integrated connection pedestal, 2-rectangular spokes, 3-rollers, 4-connecting device, 5-segments, 6-T-shaped spokes, 7-bolt holes and high-strength bolts, 8-pedestal grooves, 9-surrounding rock excavation limit. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings.

[0032] Example 1

[0033] like Figure 1 , Figure 2 , Figure 3 , Figure 5 , Figure 6As shown, this embodiment includes an integrated connection pedestal 1 and a plurality of support spokes, the front end of the support spokes is anchored and connected to the integrated connection pedestal 1, and the plurality of support spokes are arranged at equal intervals along the outer circumference of the segment. Specifically: a pedestal groove 8 is provided on the top surface of the integrated connection pedestal 1, the front part of the support spokes is embedded in the pedestal groove 8, and the integrated connection pedestal 1 is connected through bolt holes and high-strength bolts 7. Preferably, the support spokes and the integrated connection pedestal 1 can be made of materials with high strength such as steel. The sizes of the support spokes and the integrated connection pedestal 1 can be reasonably set according to needs, and the number of support spokes can also be reasonably arranged according to actual conditions, and the number of arrangements depends on the segment assembly radius and other conditions; usually, 7-15 support spokes can meet the needs.

[0034] In this embodiment, there are 11 supporting spokes, and the supporting spokes are rectangular spokes 2. The cross section of the rectangular spokes 2 is rectangular, and the central angle of the rectangular spokes 2 relative to the pipe segment is 2°. The central angle of the cross section of the integrated connection pedestal 1 is 45° to 55°; the width of the integrated connection pedestal 1 is 0.35 to 0.45m, and the length of the rectangular spokes 2 is 1.5 to 2 times the width of the pipe segment; the top and bottom surfaces of the integrated connection pedestal 1 are both arc surfaces, the top surface is flush with the top surface of the supporting spokes, and the bottom surface is flush with the inner diameter surface of the pipe segment 5. When in use, the integrated connection The connecting seat 1 is located on one side of the segment, the bottom surface of the supporting spoke is in contact with the outer arc surface of the segment 5, and the supporting spoke is freely protruding from the other side of the segment 5; a row of rollers 3 are provided on the top of the rectangular spoke 2, and the rollers 3 are arranged along the axial direction of the rectangular spoke 2, and the rolling direction of the rollers 3 is the axial direction of the rectangular spoke 2. When this embodiment is in use, the rollers 3 are in contact with the excavation limit 9; a connecting device 4 for connecting to a shield machine is provided on the integrated connecting seat 1, and the connecting device 4 can be a lockable connecting device such as a locking hook, a safety hook, or a pulling hook.

[0035] Example 2

[0036] like Figure 4 As shown, the difference between this embodiment and embodiment 1 is that the supporting spokes are T-shaped spokes 6, the cross-section of the T-shaped spokes 6 is T-shaped, and rollers are arranged on the top surface of the T-shaped spokes 6. When this embodiment is used, the top surface of the T-shaped spokes contacts the excavation limit.

[0037] The present invention also discloses a grouting method using the temporary support device, comprising the following steps:

[0038] Step 1: Assemble the pipe segment 5 and install the temporary positioning device on the top thereof for the first time;

[0039] Step 2: synchronously grouting the gap between the pipe segment 5 and the excavation limit 9;

[0040] Step 3: The shield machine advances to excavate and drives the temporary support device forward, while performing supplementary grouting;

[0041] Step 4: Assemble the pipe segment 5 to the temporary positioning device installed on the top, and then repeat the steps 2, 3, and 4 in a loop.

[0042] In order to reduce the friction between the supporting spokes and the pipe segments 5 and the surrounding rocks of the excavation limit 9, the surfaces of the supporting spokes are coated with lubricating oil.

[0043] Considering installing roller 3 on the top of rectangular spoke 2 is also to reduce the friction between the device and the rock surrounding rock 7 when withdrawing the support device; however, it is not suitable to install roller 3 in soft soil surrounding rock, and consider using T-shaped spoke 6 with a large contact area to increase the pressure between the device and the surrounding rock.

[0044] The above considerations are all to ensure that after grouting, the support device can be smoothly separated from the pipe segment to proceed to the next round of construction.

[0045] Before step 1, preparations for assembling the positioning device are performed: a certain number of supporting spokes are arranged on the integrated connection pedestal 1 according to the radius of the pipe segment 5 .

[0046] The supporting spokes are arranged in a ring direction between the segment 5 and the excavation limit 9, and play a temporary supporting role for the segment 5 when the buoyancy force acts, thereby reducing the influence of the buoyancy of the segment during the assembly and grouting process and thus the thickness of the grouting layer.

[0047] The anti-floating positioning support device of the present invention is arranged on the top of the segment and connected to the shield machine. Through the processes of installing a temporary support device, installing the segment, synchronous grouting, jacking excavation, moving the temporary support device, supplementary grouting and the like, a cyclic construction is realized. The construction process is simple and the construction quality can be significantly improved.

[0048] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, technicians familiar with the field may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A grouting method for a temporary support device for the anti-floating positioning of a shield segment, Features: The method uses a temporary support device for anti-floating positioning, the temporary support device includes an integrated connection pedestal and a plurality of support spokes, the front end of the support spokes is anchored and connected to the integrated connection pedestal, and the plurality of support spokes are arranged at equal intervals along the outer circumference of the pipe segment; the integrated connection pedestal is located on one side of the pipe segment, the bottom surface of the support spokes fits the outer arc surface of the pipe segment, and the support spokes freely protrude from the other side of the pipe segment; the top and bottom surfaces of the integrated connection pedestal are both arc surfaces, the top surface is flush with the top surface of the support spokes, and the bottom surface is flush with the inner diameter surface of the pipe segment; the integrated connection pedestal is provided with a connection device for connecting to a shield machine; the support spokes are rectangular spokes, the cross-section of the rectangular spokes is rectangular, a row of rollers are provided on the top of the rectangular spokes, the rollers are arranged along the axial direction of the rectangular spokes, and the rolling direction of the rollers is the axial direction of the rectangular spokes. When the temporary support device is in use, the rollers are in contact with the excavation limit; The grouting method comprises: step 1: assembling the pipe segments and installing the temporary support device for anti-floating positioning on the top thereof for the first time; Step 2: Synchronously grout the gap between the segment and the excavation limit; Step 3: The shield machine advances to excavate and drives the temporary support device forward, while performing supplementary grouting; Step 4: Assemble the segments to the temporary anti-floating support device installed on the top, and then repeat steps 2, 3, and 4.

2. The grouting method according to claim 1, Features: The number of the supporting spokes is 7 to 15.

3. The grouting method according to claim 1 or 2, Features: The central angle of the rectangular spokes relative to the segment is 2°, and the central angle of the cross section of the integrated connection pedestal is 45° to 55°; the width of the integrated connection pedestal is 0.35 to 0.45 m, and the length of the supporting spokes is 1.5 to 2 times the width of the segment.

Images