Anti-floating device for prefabricated track plate of subway circular shield tunnel

Abstract

The utility model provides an anti-floating device for a subway circular shield tunnel prefabricated track plate. The anti-floating device comprises corner row sets symmetrically arranged on the left side and the right side of the prefabricated track plate in the extension direction of the prefabricated track plate, a pressing rod transversely erected on the prefabricated track plate and a pressing rod fixing device connected with the two ends of the pressing rod and the corner row sets. The angle row group comprises a plurality of angle steels with L-shaped sections and U-shaped rings which are uniformly welded on any edge of the angle steels according to fixed intervals; and the other sides of the angle steels are fixedly connected with a shield segment chute. According to the anti-floating device, the fixing mode that an expansion hook is buried in a shield segment drilling hole to serve as a pressing device in the conventional process is abandoned, the deformation risk caused by long-time use of the expansion hook is avoided, and the floating problem generated after a prefabricated slab is poured and self-compacted is effectively solved; construction safety, subway driving safety, operation efficiency and riding comfort are guaranteed, and the service life of rails and vehicle equipment is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of construction technology for precast track slab bed pressing and anti-floating construction, specifically to an anti-floating device for precast track slabs used in circular shield tunnels of subways. Background Technology

[0002] With the acceleration of urbanization, subways, as an efficient and convenient mode of urban rail transit, have been widely constructed. The subway track system is a key infrastructure for subway operation, and its quality and stability directly affect the safe and comfortable operation of subway trains. Precast track slab technology is increasingly used in subway track construction, offering numerous advantages such as fast construction speed and easy quality control.

[0003] Self-compacting slabs have unique advantages in precast track systems. They can achieve a dense filling effect during construction by relying on their own properties, reducing complex procedures such as manual vibration. However, in practical applications, self-compacting slabs may float after grouting due to various reasons.

[0004] Subway trains operate at high speeds, placing extremely high demands on the smoothness and stability of the tracks. Even a slight upward movement of the track slab can cause changes in the track geometry, increasing vibration and noise during train operation, reducing passenger comfort, and potentially even jeopardizing operational safety.

[0005] Traditional track slab fixing methods have limitations in preventing self-compacting slabs from floating. Some simple fixing devices may not be effective in resisting buoyancy or are prone to failure under complex working conditions. Due to the structural characteristics of precast track slabs, track slab clamping devices are typically installed after fine-tuning, and anti-buoyancy supports are installed to prevent the track slabs from floating during pouring. To prevent the slabs from floating during the pouring of self-compacting concrete, the conventional practices are as follows:

[0006] Expansion hooks are embedded in existing tunnel lining segments drilled on-site. Before fine-tuning the track slab, edge-sealing devices are placed around the track slab. After fine-tuning, the edge-sealing devices placed around the track slab are spliced ​​and installed. Precast track pressure bars are slowly hoisted to the installation position using specialized hoisting equipment. Manual fine-tuning rods are used to position the track slab at the designated installation points, based on its structural characteristics. At both ends of each pressure bar, the locations for drilling expansion hooks are determined using end tie rods. Holes are drilled using specialized drilling equipment, and the expansion hooks are embedded in the holes. Nuts are tightened to ensure a tight connection between the bolts and the foundation. The hole-type device at the end of the tie rod is inserted into the expansion hook for a tight connection. The tie rods are then tightened symmetrically to securely fix the self-compacting plate and prevent it from floating.

[0007] The narrow and damp environment of the tunnel boring machine (TBM) restricts the operating space for workers. The damp environment reduces the insulation performance of electrical equipment, significantly increasing the risk of electric shock for workers, especially since drilling uses 220V equipment. Secondly, drilling into existing high-strength TBM segments greatly increases the labor intensity for workers. The extensive use of expansion hooks not only incurs significant costs but also requires workers to remove them with angle grinders after construction, resulting in substantial drawbacks in terms of safety, labor, energy consumption, and efficiency. Furthermore, drilling into the segments introduces numerous hazards, such as the risk of cracking, damage to the reinforcing steel cover, weakening the load-bearing capacity of the segments, and affecting the aesthetics and integrity of the structure. Utility Model Content

[0008] The purpose of this invention is to provide an anti-floating device for prefabricated track slabs in circular shield tunnels of subways, so as to overcome the shortcomings of the prior art.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] An anti-floating device for precast track slabs in circular shield tunnels for subways includes corner groups symmetrically arranged on the left and right sides of the precast track slab along its extension direction, pressure bars that are horizontally mounted on the precast track slab, and pressure bar fixing devices that connect the two ends of the pressure bars and the corner groups. The corner groups include several L-shaped angle steels with U-shaped rings welded evenly at fixed intervals to any edge of the angle steels. The other side of the angle steels is fixedly connected to the slide groove of the shield tunnel segment.

[0011] Furthermore, the angle steel and the fixed edge of the shield segment slide groove are provided with a U-shaped hole, and a T-bolt passes through the U-shaped hole to fix it to the inner wall of the shield segment slide groove; the U-shaped ring is made of threaded steel.

[0012] Furthermore, the pressure rod has waist-shaped holes at both ends, and the pressure rod fixing device includes a semi-threaded pull rod hook with one end hooked to a U-shaped ring and the other end passing through the waist-shaped hole, a locking nut sleeved on the other end of the semi-threaded pull rod hook, and a pin.

[0013] Furthermore, a pin hole is provided on the side of the pressure rod, and the pin can pass through the pin hole and abut against the upper end face of the semi-threaded pull rod hook.

[0014] As can be seen from the above technical solutions, this utility model has the following technical advantages compared with the prior art:

[0015] This utility model anti-floating device, through corner brackets, pressure rods mounted on the precast track slab, and pressure rod fixing devices connecting the two ends of the pressure rods and the corner brackets, abandons the conventional process of embedding expansion hooks in the drill holes of the shield tunnel segments as a clamping device, avoids the deformation risk caused by long-term use of expansion hooks, effectively solves the floating problem after the precast slab is poured and self-compacted, and ensures the safety of subway operation, operational efficiency, passenger comfort, and extends the service life of track and vehicle equipment;

[0016] This utility model eliminates the use of expansion hooks, replacing the disposable use of expansion hooks with the recycling of angle steel. This not only avoids the labor waste caused by cutting off the remaining expansion hooks after construction, but also directly reduces the investment in the purchase of construction materials, thereby reducing costs and increasing efficiency.

[0017] This invention avoids drilling operations in tunnel segments, which not only reduces the labor intensity of workers to a certain extent, but also reduces the man-hours consumed in the installation process, greatly improving construction efficiency. Secondly, it effectively protects the integrity, waterproof performance, and durability of the tunnel segment structure, further reducing subsequent operation and maintenance costs.

[0018] This invention eliminates the use of 220V voltage during construction, optimizes resource allocation, rationalizes the distribution and use of electrical equipment, significantly improves efficiency, and increases the utilization rate of equipment resources. At the same time, in the construction environment of tunnels where the space is relatively small, often damp, and large amounts of metal materials are used, it greatly reduces the risk of electric shock, reduces the risk of electrical fires, and improves the level of construction safety. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0020] Figure 2 This is a construction effect diagram of this utility model;

[0021] In the diagram: 1. Angle bar assembly; 11. Angle steel; 12. U-shaped ring; 13. U-shaped hole; 2. Pressure bar; 21. Waist-shaped hole; 22. Pin hole; 3. Pressure bar fixing device; 31. Semi-threaded tie rod hook; 32. Locking nut; 33. Pin. Detailed Implementation

[0022] A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

[0023] like Figure 1The anti-floating device for precast track slabs in circular shield tunnels of subways shown includes corner racks 1 symmetrically arranged on the left and right sides of the precast track slab along its extension direction, pressure rods 2 spanning the precast track slab, and pressure rod fixing devices 3 connecting the two ends of the pressure rods 2 and the corner racks 2; the pressure rods 1 are perpendicular to the extension direction of the precast track slab.

[0024] Specifically, the angle steel group 1 includes several L-shaped angle steels 11 with U-shaped rings 12 welded evenly at fixed intervals to any edge of the angle steel 11. The U-shaped rings 12 are made of threaded steel. The other side of the angle steel 11 is fixedly connected to the tunnel segment chute. In actual use, the angle steel 11 is provided with a loop hole 13 on the fixed side of the tunnel segment chute, and T-bolts are passed through the loop hole 13 to fix it to the inner wall of the tunnel segment chute.

[0025] In this preferred embodiment, the pressure rod 2 has waist-shaped holes 21 at both ends. The pressure rod fixing device 3 includes a semi-threaded pull rod hook 31 with one end hooked to the U-shaped ring 12 and the other end passing through the waist-shaped hole 21, a locking nut 32 sleeved on the other end of the semi-threaded pull rod hook 31, and a pin 33. The side of the pressure rod 2 has a pin hole 22. The pin 33 can pass through the pin hole 22 and abut against the upper end face of the semi-threaded pull rod hook 31 to ensure the stability of the pressure rod 2.

[0026] The anti-buoyancy device described in this preferred embodiment specifically includes the following construction steps:

[0027] S1. After the precast track slab is finely adjusted, the edge sealing template around the precast slab is spliced ​​and installed. Then, according to the law of dispersion of buoyancy force of the precast slab after self-compacting, pressure bars are arranged and placed. Four pressure bars are placed on each precast track slab, and the pressure bars are perpendicular to the extension direction of the precast track slab.

[0028] S2. The corner rail groups welded and assembled at the track laying base are transported to the construction site using professional transportation equipment. Four corner rails are arranged on each side of each precast track slab. T-bolts are passed through the loop holes on the corner rails and firmly and tightly fixed to the inner wall of the shield tunnel segment sliding groove.

[0029] S3. Connect one end of the hook of the semi-threaded tie rod to the U-shaped ring on the angle steel, and pass the other end through the waist-shaped hole. Then insert the pin into the pin hole to prevent the semi-threaded tie rod hook from slipping out under force, and screw the locking nut into the upper end of the semi-threaded tie rod hook.

[0030] S4. Simultaneously use a torque wrench and lock nuts on both sides of the precast slab to tighten the clamping device with a tightening force of 40 N·m. The four-sided sealing template must be installed firmly and should be in close contact with the four-sided perimeter and base of the precast slab to ensure the joint is intact and prevent concrete leakage in the gaps.

[0031] S5. After the fixing device is installed, check whether the connecting bolts of each part of the track plate clamping device are loose and whether the bolts are tight. Use a level to check the joints between adjacent track plates. If the deviation is large, readjust the track plate and make fine adjustments to meet the accuracy requirements.

[0032] This utility model anti-floating device, through corner brackets, pressure rods mounted on the precast track slab, and a pressure rod fixing device connecting the two ends of the pressure rods and the corner brackets, abandons the conventional method of embedding expansion hooks in the drilled holes of the shield tunnel segments as a clamping device. It avoids the deformation risk caused by long-term use of expansion hooks, effectively solves the floating problem after the precast slab is poured and compacted, and ensures the safety of subway operation, operational efficiency, passenger comfort, and extends the service life of track and vehicle equipment.

[0033] The above-described embodiments are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Any modifications and improvements made to the technical solutions of the present utility model by those skilled in the art without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. A device for preventing floating of precast track slabs in circular shield tunnels of subways, characterized in that, It includes corner brackets symmetrically arranged on the left and right sides of the precast track slab along the extension direction of the precast track slab, pressure bars that are cross-braced on the precast track slab, and pressure bar fixing devices that connect the two ends of the pressure bars and the corner brackets; The angle bar assembly includes several L-shaped angle steels that are uniformly welded at fixed intervals to U-shaped rings on any edge of the angle steels. The other side of the angle steels is fixedly connected to the tunnel segment slide groove.

2. The anti-floating device for prefabricated track slabs in a circular shield tunnel of a subway as described in claim 1, characterized in that, The angle steel and the fixed edge of the shield segment slide groove are provided with a U-shaped hole, and the U-shaped bolt passes through the U-shaped hole and is fixedly connected to the inner wall of the shield segment slide groove; the U-shaped ring is made of threaded steel.

3. The anti-floating device for prefabricated track slabs in a circular shield tunnel of a subway as described in claim 1, characterized in that, The pressure rod has waist-shaped holes at both ends. The pressure rod fixing device includes a semi-threaded pull rod hook with one end hooked to a U-shaped ring and the other end passing through the waist-shaped hole, a locking nut sleeved on the other end of the semi-threaded pull rod hook, and a pin.

4. The anti-floating device for prefabricated track slabs in a circular shield tunnel of a subway as described in claim 3, characterized in that, The side of the pressure rod has a pin hole, and the pin can pass through the pin hole and abut against the upper end face of the semi-threaded pull rod hook.

Images