CN116006217B - Pipe curtain structure and construction method thereof - Google Patents

Abstract

The invention discloses a pipe curtain structure and a construction method thereof, relates to the technical field of underground engineering construction, and solves the problems that in the existing pipe curtain welding process, a welding seam is narrow in construction space, the quality of the welding seam cannot be guaranteed, the welding seam is easy to break, slurry in the pipe curtain is not densely filled, and a cavity exists, and the concrete scheme is as follows: the utility model provides a pipe curtain structure, includes a plurality of pipe curtain main parts that connect gradually, every pipe curtain main part both ends are equipped with the incision in order to provide the welding space, and the incision butt joint of two adjacent pipe curtain main parts, adjacent pipe curtain main part butt joint department inner wall welding reinforcing plate, incision department welding pipe curtain apron, the inside axial of pipe curtain main part sets up first slip casting pipe, is equipped with a plurality of one-way contrary holes on the first slip casting pipe for carry out the slip casting that pressurizes in order to fill the cavity, a plurality of second slip casting pipes of pipe curtain main part outer wall fixation.

Description

A kind of pipe curtain structure and its construction method

Technical field

The invention relates to the technical field of underground engineering construction, and in particular to a pipe curtain structure and a construction method thereof.

Background technique

In recent years, underground space construction has developed rapidly, and the surrounding environment faced by underground space construction has become increasingly complex. The construction of underpasses and close connections has become the norm. When the underground space passes under or is close to sensitive buildings, important roads and other projects, it will inevitably have an impact on existing buildings (structures), and certain reinforcement measures need to be adopted to control the construction impact of the underground space. Pipe curtains have the advantages of high support stiffness and strong deformation resistance, and are widely used in construction impact control. At present, the commonly used pipe curtains are about 4-6m in length and 150mm-600mm in diameter steel pipes. After all the steel pipes are jacked, cement slurry is poured to form the pipe curtain structure. Before erecting steel pipes, foundation pits or temporary guide holes need to be excavated in advance as a pipe curtain construction platform. The steel pipes are jacked into the construction platform, welded, and continue to be jacked until they meet the designed length.

The inventor found that due to cost and safety control, the space of the pipe curtain construction platform is often small. As a result, during the pipe curtain welding process, the height of the bottom weld from the bottom of the platform is small, manual welding is difficult, and the quality of the weld is difficult to guarantee. The top of the pipe curtain It is easy to break along the welding seam during the welding process. At the same time, when the tube curtain is loaded, the bottom is often used as the tension area, and the steel pipe is the main tension structure. Once the bottom weld cracks, cracks are prone to appear at the bottom, leading to problems such as the failure of the tube curtain to bear load. In addition, after the pipe curtain is jacked, cement slurry needs to be poured to increase the bending stiffness. The expansion of the slurry often causes the top of the pipe curtain to be filled poorly. The top of the pipe curtain is the pressure area, and the cement filling body is the main pressure. Structure, if the top filling is insufficient, it will also seriously affect the bearing capacity of the tube curtain.

Contents of the invention

In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a pipe curtain structure and a construction method thereof, which ensures the operating space when constructing the first weld inside the pipe curtain through the docking of the incisions of two adjacent pipe curtain bodies. At the same time, the setting of the notch facilitates the installation of reinforcing plates and improves the connection strength between the main bodies of the pipe curtain; the first grouting pipe with a one-way check hole is provided inside the main body of the pipe curtain, which can realize pressurized grouting to solve the problem inside the pipe curtain structure. The slurry filling is not dense and there are technical problems with cavities.

In order to achieve the above objects, the present invention is achieved through the following technical solutions:

In the first aspect, a pipe curtain structure includes a plurality of pipe curtain main bodies connected in sequence. Each pipe curtain main body is provided with cutouts at both ends to provide welding space. The cutouts of two adjacent pipe curtain main bodies are butted together, and the adjacent pipe curtain main bodies are connected. The reinforcing plate is welded on the inner wall of the butt joint, and the pipe curtain cover is welded on the incision. A first grouting pipe is axially arranged inside the main body of the pipe curtain. There are multiple one-way check holes on the first grouting pipe for pressurized injection. Grouting is used to fill the cavity, and a plurality of second grouting pipes are fixed on the outer wall of the main body of the tube curtain.

As a further implementation method, the incisions are located at both ends of the main body of the tube curtain, and the incisions are V-shaped incisions. The closed shape after the incisions of the two tube curtain main bodies are butted is the same as the shape of the tube curtain cover plate.

As a further implementation, the reinforcing plates are located on the other side of the two ends of the main body of the pipe curtain. The curvature of the reinforcing plate matches the curvature of the inner wall of the main body of the pipe curtain. The reinforcing plate and the inner wall of the pipe curtain form a reinforcing plate weld.

As a further implementation, the outer curvature of the pipe curtain cover plate is the same as the outer curvature of the pipe curtain main body, and a pipe curtain cover plate weld is formed between the cutout of the pipe curtain cover plate and the pipe curtain main body.

As a further implementation method, the first grouting pipes inside the main body of each pipe curtain are fixedly connected through a sleeve. The sleeve is located at the incision. Rubber pads are installed on both sides of the inner wall of the sleeve. The rubber pads are tapered to compress the first grouting pipe. A grouting pipe.

As a further implementation, a first weld seam inside the pipe curtain is formed between the ends of two adjacent pipe curtain bodies.

As a further implementation method, the second grouting pipe is arranged axially along the main body of the pipe curtain, the second grouting pipes on two adjacent pipe curtain bodies are butted, and the second grouting end is evenly arranged circumferentially along the outer wall of the main body of the pipe curtain. .

As a further implementation, the inner diameter of the second grouting pipe is greater than the inner diameter of the first grouting pipe.

In the second aspect, a construction method of a pipe curtain structure includes the following steps:

After the pipe curtain guide pit is excavated, a pipe jacking machine is installed, and the pipe jacking machine is used to push the first pipe curtain main body into the soil layer;

The main body of the second pipe curtain is connected to the incision of the main body of the first pipe curtain, and the first weld seam inside the pipe curtain is constructed, and then the reinforcing plate is welded, and then the sleeve is used to connect the two adjacent grouting pipes, and the pipe curtain cover is welded, and so on. , until all the pipe curtain main bodies are pushed into the soil layer;

One grouting is performed outside the main body of the pipe curtain. After the first grouting is solidified, a second grouting injection is carried out under pressure through the first grouting pipe to fill the internal cavity. Then, three grouting injections are carried out outside the main body of the pipe curtain through the second grouting pipe. A tube curtain structure is formed as described above.

As a further implementation method, after the pipe jacking machine is installed, the rear end of the pipe jacking machine is matched with a reaction bracket, and the reaction bracket is supported on the side wall of the pipe curtain guide pit;

Before grouting, use a gantry crane to move the pipe jacking machine to clear the construction space.

The above-mentioned beneficial effects of the present invention are as follows:

1. The present invention uses the main body of the pipe curtain with cutouts at both ends for construction. The setting of the cutouts allows the structure to be welded from inside the pipe curtain, effectively solving the problem that the bottom of the pipe curtain is close to the bottom of the foundation pit and the welding space is small. Danger and other problems are prone to occur during welding, so the welding efficiency is improved and the safety is greatly improved.

2. The arrangement of the reinforcing plate of the present invention enhances the strength of the connection between the pipe curtain steel pipe and the steel pipe, can effectively solve the problem of pressure bending and fracture at the pipe curtain connection due to insufficient connection strength, and improves the safety of the overall structure; at the same time The setting of the notch also provides construction space for the welding of the reinforced plate.

3. The present invention can realize multi-stage grouting, thereby solving the problem of insufficient grouting at both ends of the pipe curtain. First, the coarser aggregate slurry is injected into the interior of the pipe curtain on one side of the pipe curtain through natural flow. Secondly, after the primary grouting slurry solidifies, the pressure grouting method is used to inject the inside of the pipe curtain through the first internal grouting pipe. The grouting pipe is equipped with a check valve, which can not only avoid the problem of blocking the internal grouting pipe by one grouting, but also ensure that the slurry flows into the inside of the pipe curtain to fill the cavity under pressure. Finally, the external grouting pipe is used to pressurize the soil layer between the curtain steel pipes to strengthen the connection between the curtain steel pipes and improve the stability of the stratum where they are located.

Description of the drawings

The description and drawings that 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 of the present invention.

Figure 1 is a schematic structural diagram of the main body of the tube curtain in the embodiment of the present invention.

Figure 2 is a schematic structural diagram of the first grouting pipe connected through a sleeve in the embodiment of the present invention.

Figure 3 is a schematic structural diagram of the end of the main body of the tube curtain in the embodiment of the present invention.

Figure 4 is a schematic structural diagram of the tube curtain guide pit in the embodiment of the present invention.

Figure 5 is a schematic structural diagram of the joint of the main body of the tube curtain in the embodiment of the present invention.

Figure 6 is a schematic diagram of grouting in an embodiment of the present invention.

Figure 7 is a schematic diagram of the load-bearing structure of the tube curtain in the embodiment of the present invention.

In the figure: The spacing or size between each part is exaggerated to show the position of each part, and the schematic diagram is for illustration only.

Among them: 1. Main body of pipe curtain, 2. Second grouting pipe, 3. Reinforcement plate, 4. First grouting pipe, 5. One-way check hole, 6. Pipe curtain cover plate, 7. Sleeve, 8 .Reserved holes for grouting, 9. Rubber pad, 10. Pipe curtain cover plate weld, 11. First weld inside the pipe curtain, 12. Reinforcement plate weld, 13. Pipe curtain guide pit, 14. Guide tunnel excavation , 15. Stratum reinforcement area.

Detailed ways

It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings commonly understood by one of ordinary skill in the art to which this invention belongs.

Embodiment 1

In a typical implementation of the present invention, as shown in Figures 1 to 5, a pipe curtain structure includes a plurality of pipe curtain main bodies 1 that are welded in sequence, and each pipe curtain main body 1 is provided with the same The incisions are made to provide welding space. When the two tube curtain main bodies 1 are butted, the incisions of the two adjacent tube curtain main bodies 1 are butted together. The reinforcing plate 3 is welded on the inner wall of the joint between the adjacent pipe curtain main bodies 1, and the pipe curtain cover plate 6 is welded on the incision.

When welding the main body of the pipe curtain (steel pipe), since the bottom of the main body 1 of the pipe curtain is close to the bottom of the foundation pit, the welding space is small, and danger may easily occur during welding. Through the setting of the incisions, the structure can be welded from inside the main body of the pipe curtain, effectively solving problems such as inconvenient welding, while improving the welding efficiency and greatly improving safety.

In this embodiment, the incisions are located on one side of both ends of the tube curtain main body 1 and are V-shaped incisions. The reinforcing plate 3 is located on the other side of the inner wall of both ends of the tube curtain main body 1 . The cutouts at both ends of the pipe curtain main body 1 are prefabricated in the factory in advance. During actual construction, the two pipe curtain main bodies 1 with the cutouts can be directly installed, which expands the operating space during welding of the pipe curtain main body 1 and is convenient and reliable.

Considering that the pipe curtain is easy to break along the weld during the jacking process. At the same time, when the tube curtain is loaded, the bottom is often used as a tension area, and the steel pipe serves as a tension structure. Once the bottom weld cracks, cracks are prone to appear at the bottom, leading to problems such as load-bearing failure of the tube curtain. In this embodiment, the joint between the adjacent tube curtain main bodies 1 The inner wall is welded with a reinforcing plate 3, and the curvature of the reinforcing plate 3 is adapted to the curvature of the inner wall of the main body of the pipe curtain.

Before constructing the reinforcing plate 3, the ends of the two connected pipe curtain bodies 1 need to be welded. After welding, the first weld seam 11 inside the pipe curtain is formed. After constructing the first weld 11 inside the pipe curtain, the reinforcing plate 3 is installed and welded, and a reinforcing plate weld 12 is formed at the internal butt joint of the pipe curtain body 1 .

The bottom surface of the reinforcing plate 3 in this embodiment is attached to the lower side of the inner wall of the main body of the pipe curtain, and the edge of the steel sheet (reinforcing plate) is welded to the inner wall of the main body of the pipe curtain 1; the arrangement of the reinforcing plate 3 enhances the connection between the main bodies of the pipe curtain. The strength at the joint can effectively solve the problem of bending and fracture under pressure due to insufficient connection strength at the joint of the main body 1 of the pipe curtain, and improve the safety of the overall structure.

The closed shape after the incisions of the two pipe curtain main bodies 1 are butted is the same as the shape of the pipe curtain cover plate 6. After the two pipe curtain main bodies 1 are butted and welded, the pipe curtain is closed by the pipe curtain cover plate 6, and the pipe curtain cover plate 6 is connected with the pipe curtain cover plate 6. The edges of the incisions are aligned and welded to form the pipe curtain cover plate weld 10. It can be understood that the outer curvature of the pipe curtain cover plate 6 is the same as the outer curvature of the pipe curtain main body.

As shown in Figure 1, after the multiple pipe curtain main bodies 1 are welded and jacked into the soil layer, the grouting process needs to be performed. In this embodiment, a first grouting pipe 4 is arranged along the axial direction inside the main body of the pipe curtain. A plurality of one-way check holes 5 are evenly distributed on the first grouting pipe for secondary pressurized grouting to fill the cavity. , a plurality of second grouting pipes 2 are fixed on the outer wall of the main body 1 of the pipe curtain. During the second pressurized grouting, the grout in the first grouting pipe 4 can pass through the one-way check hole 5, thereby filling the primary grouting inside the pipe curtain. The cavity and cavity left by the grout ensure the grouting effect; in addition, the one-way check hole 5 can also ensure that the grout will not enter the first grouting pipe 4 and block it during one grouting.

As shown in Figure 2, the first grouting pipes inside the main body of each pipe curtain are fixedly connected through sleeves 7. The sleeves 7 are located at the incisions. The setting of the incisions also facilitates the placement of the sleeves 7. The two inner walls of the sleeves 7 A rubber pad 9 is installed on the side. The rubber pad 9 is a cone-shaped rubber pad. As the pipe curtain main body 1 is pushed into the soil layer, the pressure of the rubber pad 9 gradually increases, effectively solving the grout leakage problem of the first grouting pipe 4 and grouting. The stability of the slurry tube is guaranteed.

It can be understood that during the construction process, the two first grouting pipes 4 need to be connected through the sleeve 7 first, and then the pipe curtain cover plate is welded to close the incision on the pipe curtain. The first grouting pipe 4 is used for secondary pressurized grouting to fill the cavity left inside the main body of the pipe curtain during the primary grouting.

As shown in Figures 1 and 3, the second grouting pipe 2 is arranged axially along the pipe curtain main body 1. The second grouting pipes 2 on the two adjacent pipe curtain bodies are butted and welded. The second grouting pipe 2 is arranged along the pipe. The outer wall of the curtain main body is evenly arranged circumferentially. The inner diameter of the second grouting pipe 2 is larger than the inner diameter of the first grouting pipe 4 .

In this embodiment, two second grouting pipes 2 are provided around each pipe curtain main body 1. The length of the second grouting pipes 2 is the same as the length of the pipe curtain main body 1. There are multiple second grouting pipes 2 on the second grouting pipe 2. There are 8 holes reserved for grouting for three groutings.

It can be understood that this embodiment can achieve three times of grouting. First, the coarser aggregate slurry is injected into the interior of the pipe curtain on one side of the pipe curtain through natural flow. Secondly, after the primary grouting slurry is solidified, grouting is performed internally. The pipe uses pressurized grouting to inject grouting into the inside of the pipe curtain through the first grouting pipe. The grouting pipe is equipped with a one-way check hole, which can not only avoid the problem of blocking the first grouting pipe inside by one grouting, but also ensure The slurry flows under pressure into the tube curtain. Finally, the external second grouting pipe is used to pressurize the soil layer between the curtain steel pipes to strengthen the connection between the curtain steel pipes and improve the stability of the stratum where they are located.

Embodiment 2

A construction method of a pipe curtain structure, using this method to form a pipe curtain structure described in Embodiment 1, specifically including the following steps:

First, the preparatory work before construction is carried out. The main body 1 of the pipe curtain with V-shaped cuts at both ends is prefabricated in the factory in advance. The second grouting pipe 2 is welded on both sides of the main body of the pipe curtain. In this embodiment, the outside of one pipe curtain main body Two second grouting pipes 2 are provided. The state of the second grouting pipe 2 after welding is shown in Figure 2.

Jacking platform guide pit excavation;

First, according to the engineering geological data and actual site conditions, the pipe curtain guide pit 13 is excavated in the middle of the pipe curtain area, as shown in Figure 4.

Tube curtain jacking;

After the pipe curtain guide pit is excavated, a pipe jacking machine is installed, and the pipe jacking machine is used to push the first pipe curtain main body into the soil layer; specifically, the pipe jacking machine is first placed in the designated position using the gantry crane above the guide pit, and the front end of the pipe jacking machine is Install a spiral rotary cutter for cutting soil and timely transporting soil. The rear end of the pipe jacking machine is equipped with a reaction bracket. The reaction bracket is supported on the side wall of the pipe curtain guide pit 13 to provide reaction force to promote the direction of the pipe curtain steel pipe. Front jacking can realize both excavating and jacking.

Pipe curtain welding;

After the main body of the previous pipe curtain enters the soil layer through the pipe jacking machine, the front end of the main body of the subsequent pipe curtain is welded to the end of the previous steel pipe. The specific operation is to first align the nozzles of the external grouting pipe to ensure that the V of the front and rear steel pipes The V-shaped opening is accurately connected. Due to the existence of the V-shaped opening, the construction space inside the pipe curtain is larger, and the first weld seam 11 inside the pipe curtain can be welded inside the main body of the pipe curtain, thus avoiding overhead welding during construction.

Secondly, due to the weak load-bearing capacity of the weld, the bottom of the pipe curtain is prone to bending and fracture due to pressure. Therefore, the reinforcing plate 3 is welded to the bottom of the inner side of the pipe curtain body to increase the stiffness of the connection between the steel pipes. , improve the overall stability of the tube curtain.

Then use sleeve 7 to connect the first grouting pipes 4 inside the main body 1 of the two pipe curtains together. The sleeve 7 is equipped with a tapered rubber pad. By hammering or other methods, the two grouting pipes and sleeves are tightly connected. connection, while also ensuring no leakage of slurry. Finally, the tube curtain cover plate 6 is welded to the tube curtain along the V-shaped incision to form a tube curtain cover plate weld 10. The schematic diagram of each weld is shown in Figure 5. After the welding is completed, the pipe jacking machine will jack up the pipe in the rear section and push the main body of the front section pipe curtain to continue to push into the soil layer. This cycle continues until all the pipe curtain main bodies are pushed into the soil layer.

grouting;

One grouting is performed on the outside of the main body 1 of the pipe curtain. After the first grouting is solidified, a second grouting is carried out under pressure through the first grouting pipe to fill the internal cavity. Then, a third grouting is carried out on the outside of the main body of the pipe curtain through the second grouting pipe. .

Specifically, since the pipe curtain is placed horizontally, cavity problems are prone to occur at the end of the pipe curtain after primary grouting. For this reason, a second grouting is required inside the pipe curtain. In particular, a wedge-shaped rubber pad 9 is installed on the inner wall of the sleeve 7. The grouting pipes inside the pipe curtain can be tightly connected under external extrusion to ensure no grout leakage during the grouting process.

After the pipe curtain main body 1 is pushed into the designed position, the pipe jacking machine is first moved using a gantry crane to clear space for grouting. Secondly, grouting is performed from the outside side of the main body of the pipe curtain to the inside of the main body of the pipe curtain. The grouting material can be concrete with coarse aggregate.

Since the grouting pipe inside the pipe curtain is provided with a one-way check hole 5, it can ensure that the slurry will not flow into the internal grouting pipe during one grouting. After the primary grouting slurry is solidified, the inside of the main body of the pipe curtain is pressurized through the first internal grouting pipe 4 for secondary grouting. Under the action of pressure, the slurry breaks through the one-way check hole 5 and flows into the internal cavity of the pipe curtain. place, and then fill the cavity formed by a grouting injection.

Finally, grouting is performed three times through the second grouting pipe 2 outside the main body 1 of the pipe curtain, so that the grout penetrates into the soil layer between the steel pipes through the reserved holes, strengthening the connection between the pipe curtains, and thereby improving the stability of the stratum where the pipe curtain is located. The tube curtain grouting is shown in Figure 6.

Backfill the guide pit of the jacking platform;

After the construction of all pipe curtains is completed, a stratum reinforcement area 15 will be formed, and then the guide pit will be backfilled. Under the load-bearing effect of the pipe curtain, the subway station construction work such as guide tunnel excavation 14 will be carried out. The load-bearing diagram of the tube curtain structure is shown in Figure 7.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims (8)

1. A pipe curtain structure, characterized in that it includes a plurality of pipe curtain main bodies connected in sequence. Each pipe curtain main body is provided with cutouts at both ends to provide welding space. The cutouts of two adjacent pipe curtain main bodies are butted, and the adjacent pipe curtain bodies are connected. The reinforcing plate is welded on the inner wall of the butt joint of the curtain main body, and the pipe curtain cover is welded on the incision. A first grouting pipe is axially arranged inside the pipe curtain main body. There are multiple one-way check holes on the first grouting pipe for processing. Press grouting to fill the cavity, and multiple second grouting pipes are fixed on the outer wall of the main body of the tube curtain; The incisions are located at both ends of the main body of the tube curtain, and the incisions are V-shaped incisions. The closed shape of the two tube curtain main bodies after the incisions are butted is the same as the shape of the tube curtain cover; The reinforcing plates are located on the other side of both ends of the main body of the pipe curtain. The curvature of the reinforcing plates matches the curvature of the inner wall of the main body of the pipe curtain. The reinforcing plates and the inner wall of the pipe curtain form a reinforcing plate weld. 2. A pipe curtain structure according to claim 1, characterized in that the outer curvature of the pipe curtain cover plate is the same as the outer curvature of the pipe curtain main body, and a pipe curtain is formed between the pipe curtain cover plate and the cutout of the pipe curtain main body. Cover welds. 3. A pipe curtain structure according to claim 1, characterized in that the first grouting pipes inside the main body of each pipe curtain are fixedly connected through sleeves, and the sleeves are located at the incisions, with both sides of the inner wall of the sleeve Install the rubber pad, which is tapered to compress the first grouting pipe. 4. A pipe curtain structure according to claim 1, characterized in that a first weld seam inside the pipe curtain is formed between the ends of two adjacent pipe curtain bodies. 5. A pipe curtain structure according to claim 1, characterized in that the second grouting pipe is arranged along the axial direction of the pipe curtain main body, and the second grouting pipes on two adjacent pipe curtain bodies are butt-jointed. The two grouting pipes are evenly arranged circumferentially along the outer wall of the main body of the pipe curtain. 6. A pipe curtain structure according to claim 5, characterized in that the inner diameter of the second grouting pipe is larger than the inner diameter of the first grouting pipe. 7. A construction method for a pipe curtain structure, characterized by including the following steps: After the pipe curtain guide pit is excavated, a pipe jacking machine is installed, and the pipe jacking machine is used to push the first pipe curtain main body into the soil layer; The main body of the second pipe curtain is connected to the incision of the main body of the first pipe curtain, and the first welding seam inside the pipe curtain is constructed, and then the reinforcing plate is welded, and then the sleeve is used to connect the two adjacent first grouting pipes, and the pipe curtain cover is welded. This cycle continues until all the pipe curtain main bodies are pushed into the soil layer; One grouting is performed outside the main body of the pipe curtain. After the first grouting is solidified, a second grouting injection is carried out under pressure through the first grouting pipe to fill the internal cavity. Then, three grouting injections are carried out outside the main body of the pipe curtain through the second grouting pipe. A tube curtain structure as described in any one of claims 1-6 is formed. 8. A construction method of a pipe curtain structure according to claim 7, characterized in that after the pipe jacking machine is installed, the rear end of the pipe jacking machine is matched with a reaction bracket, and the reaction bracket is supported on the side wall of the pipe curtain guide pit; Before grouting, use a gantry crane to move the pipe jacking machine to clear the construction space.