Positioning contour pre-burying structure and method for making continuous wall pre-reserved door hole

Abstract

The application discloses a positioning contour pre-burying structure and a method for constructing a continuous wall pre-reserved door hole. The pre-burying structure is formed by a plurality of U-shaped or U-shaped pipe fittings abutting each other to form a cutting contour corresponding to the shape of the door hole; the pipe fitting comprises a cutting pipe segment parallel to the wall body, a threading pipe segment perpendicular to the wall body and a transition elbow pipe segment. During construction, the pipe fitting is fixed based on the outer contour of the steel bar, and the threading pipe segment abuts at the corner; during formwork supporting, the opening end of the threading pipe segment abuts against one side of the formwork, and the cutting pipe segment abuts against the other side of the formwork. After the formwork is removed, the port of the threading pipe segment is naturally exposed, a pulling member is used to pass through the pipe fitting to guide a pulling rope saw to complete unilateral cutting, and the cycle is completed to achieve circular cutting. The application overcomes the prejudice that the pre-burying member is easy to displace by function partition of the pipe fitting and cooperative limiting of the double-sided formwork, realizes accurate contour positioning and smooth threading of the rope saw, eliminates the post-drilling process, and has the advantages of protecting the main reinforcement, high construction efficiency, high positioning precision and the like.

Description

Technical Field

[0001] This application relates to the field of building construction technology, specifically to a positioning contour pre-embedded structure and a method for constructing a reserved doorway in a continuous wall. Background Technology

[0002] In the construction of large underground transportation hubs, subway stations, and other projects, phased construction is often adopted to shorten the construction period. The retaining structures used to separate different construction sections are mostly diaphragm walls. To achieve connectivity between the existing structure and the subsequent structure, it is necessary to partially demolish the adjacent diaphragm walls on both sides of the already stabilized existing structure before constructing the cut-and-cover structure, thus creating openings for structural connection. Currently, the demolition of diaphragm walls mainly employs mechanical demolition or diamond wire saw cutting. The mainstream demolition processes are mechanical demolition and diamond wire saw cutting. Mechanical demolition generates significant impact and vibration, produces severe noise and dust, and easily damages the existing structure, failing to meet modern green construction requirements. While diamond wire saw cutting offers stable cutting, its construction process has significant drawbacks: after the wall is formed, the cutting outline must be determined by measurement and layout, and holes must be drilled in the wall to serve as entry and exit channels for the wire saw.

[0003] However, the diaphragm wall is thick and densely reinforced with steel bars, making it extremely prone to problems such as drill bit jamming and breakage during later drilling operations. This can even sever the main reinforcement bars, directly damaging the structure's mechanical properties. More importantly, the limited space on the construction site makes it difficult to perfectly match the design outline during the later layout and positioning process. Furthermore, the independent drilling operations make it extremely difficult to ensure that the axes of each hole are absolutely collinear, causing the wire saw to be repeatedly bent and jammed during installation, resulting in severe wear. The existing "cast the wall first, then drill for positioning" work sequence has significant construction errors and wastes resources, and can no longer meet the requirements of modern high-precision, low-damage engineering construction.

[0004] Through in-depth analysis, the inventors discovered that if the cutting trajectory could be precisely locked before the wall is poured, and a smooth and unobstructed passage for the wire saw could be reserved, it would completely revolutionize the existing process. Currently, there is no reliable structure or corresponding construction method in the industry that meets these requirements.

[0005] The information disclosed in this background section is intended only to enhance the understanding of the background technology of this disclosure and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] To address at least one of the technical problems existing in the prior art, this application provides a positioning contour pre-embedded structure and a method for constructing a reserved doorway in a continuous wall. This structure utilizes pre-embedded pipes with specific construction to form a precise cutting contour before pouring, and achieves natural exposure of the pipe opening after demolding through "double-sided abutment formwork," eliminating the need for drilling and hole finding. Simultaneously, combined with a segmented cyclic cutting method, it effectively solves the problems of rope jamming and positioning deviation.

[0007] According to one aspect of this disclosure, a positioning contour pre-embedded structure is provided, which consists of a plurality of U-shaped or U-shaped pipe fittings abutting each other to form a cutting contour corresponding to the shape of a doorway. The U-shaped or U-shaped pipe fittings include a cutting pipe segment arranged parallel to the wall, a conduit pipe segment arranged at both ends of the cutting pipe segment and perpendicular to the wall, and a transition bend connecting the cutting pipe segment and the conduit pipe segment.

[0008] In some embodiments of this disclosure, the U-shaped or U-shaped pipe fittings are made of PVC, PE, or galvanized steel pipe.

[0009] In some embodiments of this disclosure, the plurality of U-shaped or U-shaped pipe fittings are installed at the corresponding positions of the structural reinforcement or / and the outermost layer of reinforcement in the precast wall by means of fasteners, and the cut pipe segment is located outside the structural reinforcement or / and the outermost layer of reinforcement.

[0010] In some embodiments of this disclosure, the fastener is any one of a U-shaped buckle, a metal clamp, a metal wire tie, or a hose clamp.

[0011] In some embodiments of this disclosure, the transition bend is a C-shaped arc bend or an L-shaped bend formed by a pipe bender.

[0012] In some embodiments of this disclosure, corresponding sealing components are detachably installed at the two open ends of the U-shaped or U-shaped pipe fitting, and the outer end face of the sealing component is flush with or exposed outside the wall.

[0013] In some embodiments of this disclosure, the sealing member is any one of a sleeve cap, a plug-in plug, a sealing tape, or a peelable film.

[0014] According to another aspect of this disclosure, a method for constructing a reserved doorway in a continuous wall is provided, based on the pre-embedded structure of the positioning contour as described in any one of the claims, comprising the following steps: S1, Pipe prefabrication: Fabricate the U-shaped or similar pipe fittings according to the dimensions of the reserved door opening; S2, Positioning and Enclosure: After the reinforcement of the precast wall is laid out, multiple U-shaped or U-shaped pipe fittings are fixed with the outer contour of the reinforcement of the precast wall as a reference. At the corner position, the adjacent conduit segments are aligned to form a cut contour corresponding to the shape of the reserved door opening. S3, double-sided abutment formwork: install the sealing component at the open end of the conduit section; support the concrete formwork on both sides of the enclosure structure, adjust the position of the U-shaped or U-shaped pipe fitting so that the open end of the conduit section abuts against the concrete formwork on one side, and the cut pipe section abuts against the concrete formwork on the other side. S4, Template Removal: After the concrete is poured and formed, the concrete template is removed, and the open end of the conduit section is naturally exposed on the wall surface. The sealing component is then removed. S5, Single-sided cutting: Select one U-shaped or U-shaped pipe fitting, insert the traction device through one of its ports, guide it through the pipe and exit through the other port, pull the wire saw through the U-shaped or U-shaped pipe fitting, start the cutting equipment to complete the cutting of the single-sided wall. S6, Cyclic Cutting: Retrieve the wire saw, select another U-shaped or U-shaped pipe, and repeat step S5 until the circumferential cutting of the entire doorway outline is completed; S7, Remove Cut Block: Lift the cut wall block to create the preset doorway.

[0015] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages: 1. Spatial forced locking formed by the spatial arrangement and adjacent abutment of pipe segments: Since the cut pipe segments are parallel to the wall and the conduit segments are perpendicular to the wall, at the four corners of the doorway, by making the "conduit segments" of adjacent pipes abut against each other, not only is the boundary of the cut contour locked on the horizontal plane, but also the structural characteristics of the vertical placement of the pipe segments are utilized to form a strong vertical anti-displacement force under the huge lateral pressure of the poured concrete, ensuring the absolute position accuracy of the embedded structure and overcoming the technical bias of easy displacement of traditional embedded parts.

[0016] 2. Precise access with double-sided contact and "instant access upon demolding": During construction, the planar precision of the concrete formwork is utilized. By having the open end of the conduit section abut against one side of the formwork and the cut section abut against the other side, a secondary calibration of the pipe's spatial orientation is achieved. The structural design, where the outer end face of the sealing component is flush with or exposed to the outer surface of the wall, allows the eight pipe openings to be naturally located without chiseling away concrete after demolding, saving significant time in clearing and locating them.

[0017] 3. Segmented cyclic cutting without rope threading disturbance: Eliminating the cumbersome operation of traditional wire saws with multiple holes, this method utilizes four independent U-shaped fittings to sequentially complete the process of "single-sided rope threading, single-sided cutting, complete retrieval, and cycling to the next stage." This "divide and conquer" operation mode significantly reduces the traction resistance of the wire saw and the wear of the beads, greatly improving cutting efficiency.

[0018] 4. Active structural protection: Since the cutting trajectory is determined by the pre-embedded structure before pouring, the process of "blind drilling" inside the wall is completely eliminated, fundamentally eliminating the risk of drill bit jamming and damage to the main reinforcement inside the wall. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the positioning contour pre-embedded device in one embodiment of this application.

[0020] Figure 2 This is a schematic diagram of a rectangular cut outline installed on a steel reinforcement structure in one embodiment of this application.

[0021] Figure 3 This is a schematic diagram of the positioning contour pre-embedded device in the casting mold in one embodiment of this application.

[0022] In the above figures, 1 is the rectangular cut outline, 11 is the top embedded pipe assembly, 12 is the bottom embedded pipe assembly, 13 is the right embedded pipe assembly, 14 is the left embedded pipe assembly, 15 is the short straight section of the U-shaped pipe, 16 is the long straight section of the U-shaped pipe, 17 is the corner connection, 21 is the front concrete formwork, 22 is the rear concrete formwork, 3 is the fixing mechanism, 4 is the sealing component, 51 is the horizontal reinforcement, and 52 is the vertical reinforcement. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with the accompanying drawings.

[0024] Example 1: Embedded Structure

[0025] This example discloses a pre-embedded structure for positioning contours. See [link / reference] Figure 1-3 .

[0026] The structure consists of four independent U-shaped or U-shaped pipe fittings (top U-shaped fitting 11, bottom U-shaped fitting 12, right U-shaped fitting 13, and left U-shaped fitting 14) arranged around the doorway. The U-shaped structure of the fittings is specifically divided into three functional sections: a cutting section 16 parallel to the wall (used to define the cutting path of the wire saw along the length of the wall), a threading section 15 located at both ends of the cutting section and perpendicular to the wall (used for the wire saw to enter and exit the wall), and a transition bend section 17 connecting the cutting section 16 and the threading section 15 (used to smoothly change the traction direction of the wire saw). As an example, the U-shaped fittings can be made of rigid PVC pipe, and the transition bend section 17 can be bent into a C-shaped arc bend using a pipe bender, or directly made by splicing a standard L-shaped corner bend with a straight pipe.

[0027] For positioning and installation, the structure uses the structural reinforcement or outermost layer of reinforcement (horizontal reinforcement 51 or vertical reinforcement 52) ​​of the precast wall as the physical reference. Multiple U-shaped pipe fittings are installed at the corresponding positions of the reinforcement using fasteners 3 (such as U-shaped clips, metal ties, etc.). To ensure forming accuracy, the cut pipe section 16 must be close to and located on the outside of the reinforcement (i.e., close to the direction of the outer formwork of the enclosure structure) to ensure that it does not conflict with the main reinforcement of the wall during subsequent wire saw cutting.

[0028] At the corner of this embodiment, the conduit segments 15 of adjacent U-shaped pipe fittings abut and align with each other. This structural arrangement not only defines the cutting boundary but also constitutes a "cross-shaped internal support" system. When lateral pressure is generated during subsequent concrete pouring, the abutting conduit segments 15 can counteract the horizontal thrust, preventing the overall cutting contour from twisting. This is the key structural foundation for achieving high-precision positioning.

[0029] In practical engineering, technicians generally hold the prejudice that "embedded pipes are easily deformed or displaced under the lateral pressure of concrete," and therefore are reluctant to use wire saws to cut channels for pre-embedding. This application creatively designs an internal support structure in which the conduit sections 15 abut each other and a forced positioning system with double templates abutting each other. The two work together to successfully overcome this prejudice, enabling the embedded pipe to maintain high-precision positioning even when subjected to huge lateral pressure. This is a technical effect that a single structure cannot achieve.

[0030] A sealing component 4 is detachably installed at the open end of the conduit section 15. To prevent concrete seepage, after installation, the outer end face of the sealing component 4 is flush with or protrudes from the wall (for example, by using a sleeve cap fitted onto the outer wall of the pipe opening, or by using sealing tape to seal the pipe opening). After installation, the front concrete formwork 21 and the rear concrete formwork 22 are erected. The open end of the conduit section 15 is abutted against the inner wall of the front concrete formwork 21, and the cut pipe section 16 is abutted against the inner wall of the rear concrete formwork 22. This "double-sided abutment" formwork method, utilizing the rigidity and flatness of the formwork, not only ensures the absolute flushness between the pipe opening and the wall surface, but also further locks the horizontality and verticality of the entire pipe fitting. Example 2: Manufacturing Method

[0031] This example discloses a method for constructing a reserved doorway in a continuous wall, specifically including the following steps (see...). Figure 3 ): S1, Pipe Prefabrication: Based on the length and width dimensions of the door opening to be reserved, calculate and fabricate four independent U-shaped or U-shaped pipe fittings. During fabrication, special attention should be paid to ensuring a smooth transition of the centerline of the cut pipe section 16, the transition bend pipe section 17, and the conduit section 15, ensuring that the inner wall is smooth and wrinkle-free.

[0032] S2, Positioning and Enclosure: After the reinforcement of the precast wall is laid out, multiple U-shaped or U-shaped pipe fittings are fixed with the outer contour of the reinforcement of the precast wall as a reference. At the four corners of the pre-set doorway, the conduit segments 15 of adjacent pipe fittings are made to abut against each other and the ends are flush, so as to enclose and form a closed rectangular cut contour.

[0033] S3, double-sided abutment formwork: install sealing component 4 at the open end of conduit section 15; erect concrete formwork on both sides of the enclosure structure, adjust the position of U-shaped pipe fittings so that the open end of conduit section 15 abuts against the concrete formwork on one side, and the cut pipe section 16 abuts against the concrete formwork on the other side.

[0034] S4, Formwork Removal: After the concrete has been poured and reached its strength, the formwork is removed. Since the outer end face of the sealing component 4 is flush with the formwork surface beforehand, after the formwork is removed, the eight open ends of the conduit section 15 are naturally exposed on the wall surface, and the pipe openings can be found directly without any wall chiseling. Then, the sealing component 4 is removed manually.

[0035] S5, Single-sided cutting: Select one of the U-shaped pipe fittings, insert the spring wire threader (traction device) into one port facing the cutting side, guide it smoothly through the transition bend section 17, and exit from the other port. Connect the spring wire threader to the diamond wire saw, and pull the wire saw through the U-shaped pipe fitting. Start the cutting equipment to complete the straight cut of this single-sided wall.

[0036] S6, Cyclic Cutting: After cutting on one side, completely remove the wire saw from the equipment and retrieve it. Select another adjacent U-shaped pipe and repeat step S5. Through four cycles, the entire doorway outline is finally cut in a circular pattern.

[0037] S7, Remove Cutting Block: After the four sides are cut, the wall inside the doorway is completely separated from the overall structure. Use lifting equipment to lift the entire cut wall block away, thus forming the preset doorway.

[0038] Existing wire saw cutting methods all require passing through all holes in one go, with the wire saw operating in a zigzag stress state inside the wall. This example, through the "wire-by-wire traction, single-sided cutting, complete recovery, and repeated cycle" process in steps S5 and S6, breaks down the complex underground cutting action into a simple linear traction action, significantly reducing construction difficulty and equipment wear, representing a breakthrough improvement in building construction methods.

[0039] Because of the pre-embedded structure, the wire saw cutting channel is completed during the wall pouring process, which completely avoids the construction risks of drilling holes in the high-density steel wall later. This fundamentally protects the main reinforcement of the existing continuous wall from damage and plays an important role in maintaining the safety of the overall foundation pit. Example 3

[0040] As a variation, in addition to PVC, U-shaped or U-shaped pipe fittings can also be made of rigid pipes such as PE pipes or galvanized steel pipes. The sealing component 4 can be replaced by a sleeve cap, a plug-in plug, or a peelable film. The fixing component 3 can also be a metal clamp or hose clamp, fixed to the reinforcing bar by clamping or tightening with a worm gear. All the above-mentioned equivalent replacement components fall within the protection scope of this application.

[0041] Although some preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0042] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application is also intended to include such modifications and variations.

Claims

1. A positioning contour pre-embedded structure, characterized in that, It consists of multiple U-shaped or U-shaped pipe fittings that abut against each other to form a cut profile corresponding to the shape of a doorway. The U-shaped or U-shaped pipe fittings include a cut pipe section arranged parallel to the wall, a conduit pipe section arranged at both ends of the cut pipe section and perpendicular to the wall, and a transition bend connecting the cut pipe section and the conduit pipe section.

2. The positioning contour pre-embedded structure according to claim 1, characterized in that, The U-shaped or U-shaped pipe fittings are made of PVC, PE or galvanized steel pipe.

3. The positioning contour pre-embedded structure according to claim 1, characterized in that, The plurality of U-shaped or U-shaped pipe fittings are installed at the corresponding positions of the structural ribs or / and the outermost layer of reinforcing bars in the precast wall by means of fasteners, and the cut pipe section is located outside the structural ribs or / and the outermost layer of reinforcing bars.

4. The positioning contour pre-embedded structure according to claim 3, characterized in that, The fastener is any one of a U-shaped buckle, a metal clamp, a metal wire tie, or a hose clamp.

5. The positioning contour pre-embedded structure according to claim 1, characterized in that, The transition bend is a C-shaped arc bend or an L-shaped bend formed by a pipe bender.

6. The positioning contour pre-embedded structure according to claim 1, characterized in that, Corresponding sealing components are detachably installed at both open ends of the U-shaped or U-shaped pipe fitting, and the outer end face of the sealing component is flush with or exposed outside the wall.

7. The positioning contour pre-embedded structure according to claim 6, characterized in that, The sealing component is any one of the following: sleeve cap, plug-in plug, sealing tape, or peelable film.

8. A method for constructing a pre-reserved doorway in a continuous wall, characterized in that, The implementation based on the positioning contour pre-embedded structure according to any one of claims 1 to 7 includes the following steps: S1, Pipe prefabrication: Fabricate the U-shaped or similar pipe fittings according to the dimensions of the reserved door opening; S2, Positioning and Enclosure: After the reinforcement of the precast wall is laid out, multiple U-shaped or U-shaped pipe fittings are fixed with the outer contour of the reinforcement of the precast wall as a reference. At the corner position, the adjacent conduit segments are aligned to form a cut contour corresponding to the shape of the reserved door opening. S3, double-sided abutment formwork: install the sealing component at the open end of the conduit section; support the concrete formwork on both sides of the enclosure structure, adjust the position of the U-shaped or U-shaped pipe fitting so that the open end of the conduit section abuts against the concrete formwork on one side, and the cut pipe section abuts against the concrete formwork on the other side. S4, Template Removal: After the concrete is poured and formed, the concrete template is removed, and the open end of the conduit section is naturally exposed on the wall surface. The sealing component is then removed. S5, Single-sided cutting: Select one U-shaped or U-shaped pipe fitting, insert the traction device through one of its ports, guide it through the pipe and exit through the other port, pull the wire saw through the U-shaped or U-shaped pipe fitting, start the cutting equipment to complete the cutting of the single-sided wall. S6, Cyclic Cutting: Retrieve the wire saw, select another U-shaped or U-shaped pipe, and repeat step S5 until the circumferential cutting of the entire doorway outline is completed; S7, Remove Cut Block: Lift the cut wall block to create the preset doorway.

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