Shield segment anti-floating structure

Abstract

The utility model provides an anti-floating structure of a shield segment, and relates to the technical field of shield tunnel reinforcement. The structure comprises a sleeve valve pipe arranged on a duct piece at the bottom of a tunnel, the sleeve valve pipe is of a fan-shaped supporting structure, and the direction of the sleeve valve pipe is perpendicular to the tunnel duct piece and extends towards the outer side of the duct piece; the first sleeve valve pipe is located at the vertically-downward position of the center of the annular tunnel. Two side sleeve valve pipes are arranged on the two sides of the first sleeve valve pipe in the radius direction forming 45-60 degrees with the center of the annular tunnel; the middle sleeve valve pipe is arranged between the first sleeve valve pipe and the side sleeve valve pipe at an interval of 10-30 degrees; and the sleeve valve pipe and the stratum are connected together through the coagulum of the grouting slurry. Before secondary grouting, the sleeve valve pipe with the bolt head is arranged at the proper position of the duct piece at the bottom of the tunnel, the duct piece is fixed underground, diffusion type grouting is conducted through the pipe wall hole of the sleeve valve pipe, after grout is solidified, the outer wall of the sleeve valve pipe and the soft soil stratum of the annular area where the sleeve valve pipe is located can be combined into a whole, and the duct piece is prevented from floating upwards.

Description

Technical Field

[0001] The utility model relates to the technical field of shield tunnel reinforcement, in particular to an anti-floating structure of a shield segment. Background Art

[0002] Soft soil is a special type of underconsolidated soil with the characteristics of high water content, underconsolidation, low bearing capacity, high compressibility and large settlement. Shield construction is often used to carry out subway projects under complex geological conditions. The construction layer of urban subways is relatively complex, and construction in the soft soil layer may be encountered. When the groundwater level in the construction area containing the soft soil layer changes, the shield segments are very likely to float up due to the low longitudinal stiffness of the soft soil layer. Especially when the shield tail passes through the soft soil layer, the segments are very likely to float up after being assembled and connected due to the geological characteristics. Excessive floating of the shield tunnel will also cause the joints of the tunnel structure to open and misalign, which may cause water leakage and structural damage in severe cases. This not only affects the safety of subway construction to a great extent, but also lays hidden dangers for subsequent use; some projects are even so serious that slope adjustment needs to be set to meet the line design, which greatly prolongs the construction period and causes considerable economic losses.

[0003] In order to ensure that the line shape of the subway tunnel meets the design and guarantee the quality of the project, the displacement of the shield segment floating up must be controlled within the specified reasonable range during the tunnel construction and subsequent maintenance. The traditional anti-floating method is to open the grouting hole at the bottom of the tunnel to release the pressure, release the pressurized water and unsolidified cement mortar at the bottom of the segment, and then use the grouting material with a faster solidification speed through the grouting hole for secondary grouting for reinforcement, or use the physical structure of anti-floating plates and pull-out piles. However, the effect of this method is not ideal: these measures are limited to single grouting: secondary grouting cannot ensure that the gaps in the segment are completely filled, and the physical structure cannot play a role repeatedly, so there will be hidden dangers of continued floating in the future. Utility Model Content

[0004] In view of the shortcomings of the prior art, the purpose of the utility model is to provide a shield segment anti-floating structure, which performs diffusion grouting through sleeve valve tubes to ensure that the outer wall of the sleeve valve tube and the stratum in the annular area can be combined into one after the slurry solidifies, thereby preventing the segment from continuing to float up.

[0005] A shield segment anti-floating structure comprises a plurality of fan-shaped sleeve valve tubes arranged on the tunnel bottom segment, the sleeve valve tubes are perpendicular to the tunnel segment and extend toward the outside of the segment; the first sleeve valve tube is located at a vertically downward position from the center of the annular tunnel; two edge sleeve valve tubes are arranged on both sides of the first sleeve valve tube at a radius of 45 to 60 degrees from the center of the annular tunnel; an intermediate sleeve valve tube is arranged between the first sleeve valve tube and the edge sleeve valve tube at an interval of 10 to 30 degrees; the sleeve valve tube and the stratum are connected together by the solidified material of the grouting slurry.

[0006] Optionally, the tube wall of the sleeve valve tube has a through tube wall hole, and the outer hole diameter of the tube wall hole is 1 to 10 mm.

[0007] Optionally, the tube wall holes are arranged in a plum blossom shape.

[0008] Optionally, the head of the sleeve valve tube is a movable rotating head.

[0009] Optionally, the sleeve valve tube extends out of the pipe segment through a drilled hole on the pipe segment.

[0010] Optionally, the sleeve valve tube is a spiral hollow sleeve valve tube.

[0011] Optionally, the tail of the sleeve valve tube remaining on the inner side of the pipe segment is detachably sealed with a grooved channel steel component.

[0012] The beneficial effects of the utility model are as follows:

[0013] 1. Before the secondary grouting, the utility model arranges a sleeve valve tube with a bolt head at a suitable position of the tunnel bottom segment to fix it underground, and performs diffusion grouting through the tube wall holes of the sleeve valve tube. After the slurry solidifies, the outer wall of the sleeve valve tube can be combined with the soft soil layer in the annular area to prevent the segment from floating up.

[0014] 2. The utility model adopts a spiral hollow sleeve valve tube, the head of which is blocked by a movable rotating head, and the tail is blocked by a detachable grooved channel steel component, which can be repeatedly grouted to improve the anti-floating effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention.

[0016] In the figure: the distances or sizes between parts are exaggerated to show the positions of various parts, and the schematic diagram is for illustration only.

[0017] Figure 1 It is a schematic diagram of the anti-floating structure of the shield segment in a specific implementation manner;

[0018] Figure 2 Schematic diagram of the structure of the sleeve valve tube.

[0019] Figure 3 It is a structural schematic diagram of a grooved channel steel component.

[0020] Among them, 2. pipe segment; 3. grooved channel steel component; 4. pipe wall hole; 5. lower tangent line of the annular pipe segment; 6. first sleeve valve pipe; 7. edge sleeve valve pipe; 8. middle sleeve valve pipe; 11. sleeve valve pipe wall; 12. sealing ring; 13. grouting core pipe; 14. plum blossom-shaped pipe wall hole. DETAILED DESCRIPTION

[0021] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0022] Embodiment 1:

[0023] like Figure 1 As shown, a shield segment anti-floating structure comprises a plurality of fan-shaped sleeve valve tubes arranged on the tunnel bottom segment 2; the direction of the sleeve valve tube is perpendicular to the tunnel segment 2 and extends to the outside of the segment 2; the first sleeve valve tube 6 is located at a vertical downward position from the center of the annular tunnel; two side sleeve valve tubes 7 are arranged on both sides of the first sleeve valve tube 6 at a radius of 45 to 60 degrees to the center of the annular tunnel; an intermediate sleeve valve tube 8 is arranged between the first sleeve valve tube 6 and the side sleeve valve tube 7 at an interval of 10 to 30 degrees; the sleeve valve tube and the soft soil layer are connected together by the solidified material of the grouting slurry.

[0024] The tube wall of the sleeve valve tube is provided with a through tube wall hole 4, and the outer hole diameter of the tube wall hole 4 is 1-10 mm.

[0025] The head of the sleeve valve tube is a movable rotating head; the movable rotating head can move and rotate in multiple directions; after the internal texture corresponds to the spiral sleeve valve tube, it can be disassembled and installed. It is a flexible device to realize secondary and multiple grouting of the sleeve valve tube.

[0026] The sleeve valve tube extends out of the pipe segment 2 through the drilled hole on the pipe segment 2.

[0027] The grouting slurry is sulfate cement slurry.

[0028] The tail of the sleeve valve tube remaining inside the pipe segment 2 is detachably blocked by a grooved channel steel component 3.

[0029] The sleeve valve pipes are all extended into the soft soil layer and submerged in the plum blossom-shaped pipe wall holes 14; taking the first sleeve valve pipe 6 as an example, it will be extended below the lower tangent line 5 of the annular pipe segment.

[0030] The annular segment is located above the lower tangent line 5 of the annular segment, and the soil layer below the lower tangent line 5 of the annular segment is a soft soil layer.

[0031] The sleeve valve tube is a spiral hollow sleeve valve tube;

[0032] like Figure 2 As shown, the spiral hollow sleeve valve tube sleeve valve tube comprises a sleeve valve tube wall 11, a grouting core tube 13 is arranged inside the sleeve valve tube, and a hole is opened on the side wall of the grouting core tube 13, so that the grouting material can be moved along ( Figure 2The side wall opening of the grouting core pipe 13 (the path shown by the dotted line in FIG. 1 ) enters the inner side of the pipe wall hole 4 of the sleeve valve pipe, and passes through the pipe wall hole 4 to be combined with the surrounding soil layer;

[0033] There is a sealing ring 12 outside the pipe wall hole 4 on the inner side of the sleeve valve pipe to prevent the grouting material from penetrating into the sleeve valve pipe wall 11 outside the sealing ring 12.

[0034] The structure of the grooved channel steel component 3 is as follows Figure 3 As shown, there is a threaded blind hole in the center of the grooved channel steel component 3, which is open on the side away from the channel steel wing plate. The thread size of the blind hole matches the thread size of the tail pipe opening of the sleeve valve tube, and is used to connect with the tail pipe opening of the sleeve valve tube; the channel steel wing plate of the grooved channel steel component 3 is located on the side facing away from the pipe segment 2, and is used to twist the grooved channel steel component 3 with the help of a tool to achieve the installation and disassembly of the grooved channel steel component 3, and then block or open the tail pipe opening of the sleeve valve tube.

[0035] The specific construction process is as follows, and the specific equipment solution is as follows: Figure 1 As shown:

[0036] S1. Select the hole position of the first sleeve valve tube 6 as the center hole position vertically according to the central axis of the annular segment; take the maximum limit angle of 60° and the maximum interval limit angle of 30° as an example, select two holes on the left and right sides of the center hole position respectively, and use the crawler down-the-hole drill rig HC060 to drill holes;

[0037] Before setting the hole opening parameters, it is necessary to first determine the thickness of the pipe segment 2 and the grouting layer to clarify the minimum drilling depth. The drilling depth should be much greater than the thickness of the pipe segment 2 and the grouting layer. If the current construction situation has been determined to be 0.6m for the pipe segment and 0.3m for the grouting layer, then the parameters are set to 100mm for the hole diameter and 2m for the drilling depth.

[0038] S2, according to the thickness of the pipe segment, the thickness of the grouting layer and the height of the soft soil layer, a pipe wall hole 4 is opened on the side wall of the sleeve valve pipe, so that the cement slurry can leak out from the pipe wall hole 4, and the sleeve valve pipe with the pipe wall hole 4 is inserted into the stratum outside the pipe segment 2 along the opening in S1;

[0039] Among them, if a spiral hollow sleeve valve tube with a diameter of 100 mm is selected, a tube wall hole 4 is opened at a distance of 1 m from the root of the sleeve valve tube, and the positions of the tube wall holes 4 are arranged in a plum blossom shape.

[0040] S3. Use sulphoaluminate cement slurry (initial setting time 30 to 50 minutes, final setting time 20 minutes to 1 hour, water-cement ratio of 1) to inject grout along the sleeve valve pipe. The injection slurry penetrates through the pipe wall hole 4 and penetrates below the lower tangent line 5 of the annular segment to form a gripping force to control the segment 2 to float upward.

[0041] S4. After the grouting is completed, the sleeve valve tube is sealed with the grooved channel steel component 3. If grouting needs to be continued later, the grooved channel steel component 3 is unscrewed and the subsequent grouting operation is performed through the sleeve valve tube.

[0042] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A shield segment anti-floating structure, characterized in that: It includes a plurality of fan-shaped sleeve valve tubes arranged on the tunnel bottom segments, and the direction of the sleeve valve tubes is perpendicular to the tunnel segments and extends to the outside of the segments; the first sleeve valve tube is located at a vertically downward position from the center of the annular tunnel; two side sleeve valve tubes are arranged on both sides of the first sleeve valve tube in a radial direction of 45 to 60 degrees to the center of the annular tunnel; an intermediate sleeve valve tube is arranged between the first sleeve valve tube and the side sleeve valve tube at an interval of 10 to 30 degrees; the sleeve valve tube and the formation are connected together by the solidified material of the grouting slurry.

2. The shield segment anti-floating structure according to claim 1, characterized in that: The tube wall of the sleeve valve tube is provided with a through tube wall hole, and the outer hole diameter of the tube wall hole is 1 to 10 mm.

3. The shield segment anti-floating structure according to claim 2, characterized in that: The holes on the tube wall are arranged in a plum blossom shape.

4. The shield segment anti-floating structure according to claim 1, characterized in that: The head of the sleeve valve tube is a movable rotating head.

5. The shield segment anti-floating structure according to claim 1, characterized in that: The tail of the sleeve valve tube remaining on the inner side of the pipe segment is detachably sealed with a grooved channel steel component.

6. The shield segment anti-floating structure according to claim 5, characterized in that: There is a blind hole with thread in the center of the grooved channel steel component, which is open on the side away from the channel steel wing plate. The thread size of the blind hole matches the thread size of the tail pipe opening of the sleeve valve pipe; the channel steel wing plate of the grooved channel steel component is located on the side facing away from the pipe segment.

7. The shield segment anti-floating structure according to claim 1, characterized in that: The sleeve valve tube is a spiral hollow sleeve valve tube.

8. The shield segment anti-floating structure according to claim 7, characterized in that: The spiral hollow sleeve valve tube comprises a sleeve valve tube wall, a grouting core tube is arranged inside the sleeve valve tube, and a hole is opened in the side wall of the grouting core tube, so that the grouting material can enter the inner side of the tube wall hole of the sleeve valve tube along the side wall opening of the grouting core tube.

9. The shield segment anti-floating structure according to claim 8, characterized in that: A sealing ring is arranged outside the pipe wall hole range on the inner side of the sleeve valve pipe to prevent the grouting material from penetrating into the pipe wall range of the sleeve valve pipe outside the sealing ring.

10. The shield segment anti-floating structure according to claim 1, characterized in that: The sleeve valve tube extends out of the pipe segment through the drilled hole on the pipe segment.

Images