I-shaped middle partition wall connecting structure and construction method thereof

Abstract

The invention relates to an I-shaped middle partition wall connecting structure and a construction method thereof. Each I-shaped wall body unit is composed of two main wall bodies and a mid-partition wall, reinforcement cages in the wall bodies are two T-shaped reinforcement cages, extension socket reinforcement cages of the two T-shaped reinforcement cages are located in the mid-partition wall and connected through extension socket connectors, and the extension socket connectors are provided with reinforcement meshes used for lap joint and grout stopping plates. During construction, an I-shaped wall body unit is divided into a first-opened T-shaped unit groove section and a closed T-shaped unit groove section, after the first-opened groove section forms a groove, the T-shaped reinforcement cage and the extension socket connector are lifted and placed into the groove together, the connector box is lifted and placed into the groove on the outer side of the extension socket connector, a groove gap outside the connector box is filled, concrete is poured, then the groove section is formed and closed, and the connector box is ejected and pulled out. And the T-shaped reinforcement cage is hung into the groove, and concrete is poured. The construction operation such as grooving and pouring of the I-shaped underground diaphragm wall is greatly facilitated, the construction efficiency is improved, and the engineering quality is guaranteed.

Description

Technical Field

[0001] The invention relates to an I-shaped intermediate partition wall connection structure suitable for an I-shaped underground continuous wall and a construction method thereof. Background Art

[0002] Existing underground continuous walls (for example, anti-collision walls) are mostly I-shaped structures or L-shaped structures. There is no intersection of multiple walls in the wall. The strength requirements of the wall can be met by connecting adjacent steel cages with joint pipes, cross steel plate joints, I-shaped steel joints, and reinforced concrete prefabricated joints. For example, Chinese patent document CN115821901A discloses a construction method for a high-strength underground continuous wall, including placing a first steel cage in a preset area of ​​the construction site; installing a joint box to the end of the first steel cage; the joint box has an isolation chamber, and the end of the first steel cage extends into the isolation chamber; a casting space is formed between the middle space of the first steel cage and the joint box; concrete in a fluid state is injected into the casting space; after the concrete solidifies, the joint box is removed; the end of the first steel cage is exposed outside the concrete; a second steel cage is placed in the preset area; the space formed between the middle of the second steel cage and the formed concrete forms a second casting space; concrete in a fluid state is injected into the second casting space; and the concrete solidifies to form a complete wall. The connection of the steel cage can be made between the two solidified concretes, which greatly improves the structural strength of the concrete walls on both sides, so that it can withstand large pressure and shear force in all directions. Chinese patent document CN108035337A discloses a joint for underground continuous wall and a construction method of underground continuous wall. The joint is composed of a U-shaped steel plate and a straight steel plate, one end of the straight steel plate is connected to the bottom of the U-shaped steel plate along the symmetry axis, and the construction method of the underground continuous wall is that the joint is set at the joint of the two continuous walls, the joint is placed horizontally in the continuous wall, the straight end of the joint is welded on one side of the steel cage, and the other side is convex, the convex binding end of the rear steel cage is embedded in the U-shaped groove of the front continuous wall joint, and the rear concrete continuous wall is cast. The joint combines the anti-seepage and waterproof characteristics of the straight steel plate joint and the I-shaped steel joint, one end of the joint is welded to the steel cage to maintain integrity, and the other end makes the steel cage embedded in the U groove, increasing the contact area and the inflection point, and strengthening the waterproof effect; and the continuous wall construction method is simple and easy to operate, has good waterproof effect, and is relatively low in cost. Chinese patent document CN118563758A discloses a steel bar structure for underground continuous wall casting, including several first steel bar cages and several second steel bar cages, a second steel bar cage is arranged between two adjacent first steel bar cages, a joint plate is arranged between the first steel bar cage and the second steel bar cage, the joint plate is arc-shaped and sealing strips are arranged on both sides of the opposite sides, the joint plate is fixedly connected to the first steel bar cage at the center of the side facing away from the second steel bar cage, and a joint pipe is attached to the side of the joint plate facing away from the adjacent first steel bar cage, and the end of the joint pipe inserted into the slot section is truncated to force the two ends of the arc of the joint plate to be far away, so that the concrete slurry injected into the slot section can obtain sufficient connection strength with the soil layer and the guide wall during the solidification process, and it is not easy to cause a significant impact on the extraction of the joint pipe. These existing technologies have their own characteristics and are suitable for their respective occasions, but they still have certain limitations.For example, in some cases, it is necessary to set up two rows of parallel ground-connected walls, and set up several reinforced concrete tie plates (middle partition walls) between the two rows of ground-connected walls to improve the overall strength and stability. Based on the needs of on-site construction, the steel cage used is a T-shaped steel cage, and the inner ends (row plug ends) of the two T-shaped steel cages are butt-jointed in the middle of the middle partition wall, and the main reinforcement at the connection part must meet the 35d overlap requirement. For example, in the case where the overlapping main reinforcement is a 25-diameter third-grade steel bar, the overlap length should not be less than 875mm. If the overlap length does not meet the requirements, it will affect the quality of the entire project and the stability of the wall. Since the existing ground-connected wall steel cage connection method cannot achieve this main reinforcement overlap, it is necessary to develop a steel cage joint suitable for this type of wall, and construct a corresponding steel cage connection structure and corresponding construction method based on the developed steel cage joint. Summary of the invention

[0003] The purpose of the present invention is to provide an I-shaped intermediate partition wall connection structure suitable for an I-shaped underground continuous wall and a corresponding construction method.

[0004] The technical solution of the present invention is: an I-shaped middle partition wall connection structure, including an I-shaped wall (I-shaped wall unit), the I-shaped wall is composed of two main walls (unit main walls) arranged in parallel and a middle partition wall located between the two main walls and perpendicular to the main walls, the two ends of the middle partition wall are respectively connected to the middle of the two main walls as a whole, two T-shaped steel cages are arranged in the I-shaped wall, the T-shaped steel cages include a main steel cage located in the main wall of the corresponding side and a row steel cage located in the middle partition wall, a row joint is arranged between the row steel cages of the two T-shaped steel cages, and the row joint includes An I-beam is vertically arranged, and its two wing plates are parallel to the wall surface of the tie wall. A steel mesh is provided on each of the lateral sides of the wing plate. The steel mesh extends laterally from the corresponding side of the wing plate and is overlapped on (located at) the outer side of the row of T-shaped steel cages. The row of T-shaped steel cages is provided with a plug-in portion (located near the outer end area), and the plug-in portion is inserted between the two wing plates of the I-beam of the corresponding row of plug-in joints and the two steel mesh plates respectively extending from the two wing plates, thereby making the steel mesh plates on the wing plates overlapped on (located at) the outer side of the row of steel cages on the corresponding side.

[0005] Furthermore, the steel mesh is provided with a plurality of transverse bars (transverse steel bars) distributed up and down, and with or without longitudinal bars (longitudinal / vertical steel bars) cross-connected with the transverse bars to form a mesh structure. In the case where longitudinal bars cross-connected with the transverse bars to form a mesh structure are not provided, one or more vertical (longitudinal) or oblique (non-parallel to the transverse and longitudinal) extending steel bars may be provided to fix and connect the transverse bars into a whole, so as to facilitate on-site operations.

[0006] Preferably, the inner ends of the steel mesh (eg, the inner ends of each transverse reinforcement) are welded to the outer sides of the corresponding wing plates.

[0007] Typically, the specifications and spacing of the transverse bars on the steel mesh may be consistent with the specifications and spacing of the transverse bars on the row steel cage of the T-shaped steel cage.

[0008] Preferably, both wing plates of the I-beam are provided with stop slurry plates (or stop slurry plates), and the stop slurry plates extend (extend laterally) from at least one side (one lateral side) of the wing plate, and may also extend from both sides to facilitate on-site operations.

[0009] The stop grouting piece is rectangular and should have appropriate flexibility so as to be attached to the groove wall under the pressure of the injected concrete. For example, the stop grouting piece can be a rectangular thin iron sheet.

[0010] Furthermore, the main steel cage and the inserted steel cage of the T-shaped steel cage are both rectangular cage-shaped, and the vertical position and span (vertical dimensions) of the inserted steel cage correspond to the reinforced concrete section of the middle partition wall, and are used as steel bars for the reinforced concrete section of the middle partition wall. The middle partition wall is provided with a concrete section (plain concrete section) located above and / or below its reinforced concrete section, or the middle partition wall is not provided with a plain concrete section.

[0011] Preferably, the row of inserted steel bars of the T-shaped steel bar cage is provided with an inserting portion for inserting a row of inserted joints (inserted between the two wing plates on the corresponding sides of the I-beam and the two steel meshes respectively extending from the two wing plates), and the width of the inserting portion is smaller than the width of the main part of the row of inserted steel bars cage, and a transition section with a gradually decreasing width is provided between the main part of the row of inserted steel bars cage and the inserting portion.

[0012] Preferably, the ends of the two ends (the two ends in the horizontal direction / the two ends in the length direction of the main wall) of the main steel cage of the T-shaped steel cage are respectively concave in elevation (a concave shape running through the entire elevation of the end) and convex in elevation (a convex shape running through the entire elevation of the end), which can be respectively called concave ends or convex ends.

[0013] Preferably, the concave and convex facades are both in the shape of folded surfaces with edges located in the middle, and the angles are usually equal or similar to achieve socket-type flexible connection at both ends of adjacent main reinforcement cages.

[0014] According to the construction method of any I-shaped partition wall connection structure disclosed in the present invention, any I-shaped wall unit is divided into two T-shaped unit groove sections, namely, the first opening section and the closed section, and the first opening section is excavated first. After the groove is formed, the T-shaped steel bar cage and the plug-in connector are hoisted into the groove together, the plug-in end (the end of the plug-in steel bar cage) of the T-shaped steel bar cage is inserted between the two wing plates on the corresponding side of the I-beam of the plug-in connector, and the joint box is hoisted into the groove outside the plug-in connector (facing away from the T-shaped steel bar cage side), and the inner end (towards the I-beam waist plate end) of the joint box is inserted between the two wing plates on the corresponding side of the I-beam of the plug-in connector, and abuts against the waist plate of the I-beam (or web), hoist the joint pipe into the groove outside the concave end of the main steel cage of the T-shaped steel cage, the inner side of the joint pipe (towards the main steel cage) is located in the concave shape of the facade, fill the groove gap at the outer end of the joint box, fill the groove gap outside the joint pipe, pour concrete, complete the construction of the first grooving section, excavate the closed grooving section, after the grooving is completed, pull out the joint box, hoist the T-shaped steel cage into the groove, hoist the joint pipe into the groove outside the concave end of the main steel cage of the T-shaped steel cage, the inner side of the joint pipe (towards the main steel cage) is located in the concave shape of the facade, fill the groove gap outside the joint pipe, and pour concrete.

[0015] Preferably, when only one side (lateral side) of the plug connector is provided with a stop plate, this side is directed toward the T-shaped steel cage of the first slotted section.

[0016] Before hanging the T-shaped steel cage, if it is connected to a completed trough section of the same main wall, pull out the joint pipe (if any) on the adjacent side of the completed trough section.

[0017] The trough cleaning should be carried out according to actual needs.

[0018] Mud should be injected according to actual needs, and mud circulation and replenishment should be implemented.

[0019] Guide walls should be set up according to actual needs.

[0020] The beneficial effects of the present invention are as follows: since an upright I-beam is used as the main body of the row and plug joint, and steel mesh sheets extending to both sides are respectively arranged on the two wing plates, the connection between the row and plug ends of the T-shaped steel cages on both sides and the plug and plug joint can be realized by a socket connection method, and the steel mesh sheets extending from the joint are overlapped on the outer side of the corresponding side steel cage, which meets the main reinforcement overlap length requirement and realizes a reliable connection between the steel cage and the joint; since a stop grout sheet is arranged on the outer side of the steel mesh sheet on at least one side of the row and plug joint, the side of the row and plug joint with the stop grout sheet facing the steel cage in the first slot section, when pouring, the injected concrete pushes the stop grout sheet to the slot wall, blocks the corresponding bypass channel of the concrete, effectively avoids the bypass phenomenon, and ensures the construction quality; since a T-shaped slot section is adopted, the connection of the two T-shaped steel cages in the middle of the middle partition wall is realized through the row and plug joint, thereby not only ensuring the pulling and supporting effect of the middle partition wall on the main walls on both sides, but also greatly facilitating the construction operations such as grooving and pouring of the I-shaped ground-connected wall, which helps to improve the construction efficiency and ensure the project quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a three-dimensional schematic diagram of a steel cage connection structure in an I-shaped partition wall connection structure according to the present invention; Figure 2 It is a front view schematic diagram of a steel cage connection structure in an I-shaped partition wall connection structure according to the present invention; Figure 3 It is a top view schematic diagram of a steel cage connection structure in an I-shaped partition wall connection structure according to the present invention; Figure 4 It is a top view schematic diagram of the power strip connector involved in the present invention; Figure 5 It is a top view schematic diagram of a T-shaped steel cage involved in the present invention; Figure 6 It is a top view schematic diagram of an I-shaped underground continuous wall involved in the present invention; Figure 7 The invention relates to a construction flow chart.

[0022] Markings in the figure: 11. Main wall; 12. Middle partition wall; 20. Plug-in joint; 22. I-beam waist plate; 23. I-beam wing plate; 25. Steel mesh for overlapping on the plug-in joint; 27. Stop grout; 28. Stop grout to fix steel bars; 30. T-shaped steel cage; 31. Main steel cage; 32. Truss; 33. Concave end; 35. Convex end; 36. Plug-in steel cage; 37. Connecting part. DETAILED DESCRIPTION

[0023] See also Figure 1-Figure 7The present invention relates to an I-shaped (or H-shaped) anti-collision wall or other similar underground continuous walls in occasions such as rivers. Such an I-shaped underground continuous wall is provided with two parallel main walls 11, and a plurality of concrete tie plates 12 perpendicular to the main walls are arranged between the two main walls, which can be called a middle partition wall (or a transverse partition wall, or a transverse partition beam). The vertical dimension of the middle partition wall can be significantly smaller than the vertical dimension of the main wall, and usually corresponds to the middle upper part or the upper part of the main wall in the vertical direction. The two ends of the middle partition wall are respectively connected to the main wall on the corresponding side, and at least a part (a section in the vertical direction) of the middle partition wall is built-in with steel bars. For example, in one example, the middle partition wall is a reinforced concrete structure at a distance of 11.5m-14.5m from the ground, and the rest is a plain concrete structure.

[0024] Due to the influence of site and geological conditions, it is often difficult to implement I-shaped slot segment formation and I-shaped steel cage hanging on site. The slot of an I-shaped wall unit is divided into two T-shaped slot segments. Correspondingly, the steel cage is also set to be T-shaped. First, a T-shaped slot segment (which can be called the first slot segment) is constructed, and then the other T-shaped slot segment (which can be called the closed slot segment) is constructed. The row of steel cages of the two T-shaped steel cages is connected through the row of joints 20 to form the required I-shape.

[0025] In the T-shaped steel cage 30, the portion located in the main wall is equivalent to a large rectangular steel cage, which can be called a main steel cage (the main steel cage of the T-shaped steel cage) 31, and the portion located in the middle partition wall (half of the middle partition wall) is equivalent to a small rectangular steel cage, which can be called a plug-in steel cage (the plug-in steel cage of the T-shaped steel cage) 36. The end of the plug-in steel cage (the outer end in the horizontal direction) can be called the plug-in end (the plug-in end of the T-shaped steel cage). The main steel cage and the plug-in steel cage in the T-shaped steel cage are prepared as one piece, and the main bars in the plug-in steel cage that are perpendicular to the main steel cage (main wall) extend into the main steel cage (up to the outer steel mesh of the main steel cage) and are connected to the main bars in the main steel cage (for example, welded).

[0026] The row plug ends of the two T-shaped steel cages butt-jointed into an I-shape are respectively plugged into the corresponding side sockets of the row plug joint (between the two wing plates on the corresponding side of the I-beam and the steel mesh on the outside of the two wing plates). The row plug joint adopts an I-beam (or H-shaped steel) row plug joint. Rectangular steel meshes 25 for overlapping the row plug steel cage of the corresponding T-shaped steel cage are welded on both sides of the two wing plates 23 of the I-beam. After the row plug end is inserted into the row plug joint, the two steel meshes on the corresponding side of the row plug joint are respectively overlapped on both sides of the row plug steel cage.

[0027] 1) Production of I-beam socket connector The I-beam in the plug-in connector is set upright when in use. The outer surfaces of the two wing plates are welded with steel mesh extending from both sides in the width direction (corresponding to the horizontal direction of the wall surface at the corresponding part). The steel mesh is usually composed of a number of transverse bars and a number of longitudinal bars / vertical bars cross-connected, or it can be a number of transverse bars distributed up and down. No longitudinal bars are provided to connect them to form a mesh structure. One or more longitudinal bars (or oblique bars) can be welded to connect the transverse bars into a whole to facilitate operation. The steel bars and distribution method on the steel mesh can be consistent with the steel mesh on the plug-in steel cage (the steel mesh constituting the large surface). The vertical position of the steel mesh on the plug-in connector is adapted to the vertical position of the plug-in steel cage in the T-shaped steel cage to achieve the required overlap. The length of the steel mesh (the dimension in the length direction of the wall) can be appropriately set according to the overlap length requirements to meet the overlap requirements. In one example, the steel mesh uses Ф25 steel bars, the mesh length is 870mm, the width (vertical dimension) is 660mm, and the I-beam height is 15.5m.

[0028] In order to prevent the concrete from flowing around during the pouring process, a stop plate (or stop plate) 27 is provided on the plug connector. For example, a thin iron sheet with a thickness of 0.2 mm and a width of 1000 mm is laid on the outer sides of the two wing plates and the steel mesh of the I-beam, and is compacted with a fixed steel bar (pressed bar) 28 with a diameter of 10 mm and fixed to the outer side of the wing plate of the I-beam. The upper and lower ends of the press bar can be welded to the wing plate.

[0029] Prepare a joint box that matches the row plug connector. For the first slot section, hang the joint box on the other side of the row plug connector to resist the pressure of the concrete on the row plug connector and ensure the stability of the row plug connector during the pouring process. The joint box is a box (columnar) that adapts to the socket of the row plug connector. When in use, insert the row plug connector into the socket on the corresponding side (between the two wing plates and the steel mesh connected to the two wing plates). The inner end of the joint box is against the waist plate 22 of the I-beam, and the outer side of the joint box (facing away from the row plug connector) The steel plate is located outside the socket of the row plug connector, and its width (the size in the direction of the wall width) is greater than the width of the main part of the joint box, which is roughly equal to the slot width. After being hoisted into place, fill the gap on the back side of the joint box (the gap in the slot) with sand and gravel to support the joint box and prevent the joint box from moving or tilting.

[0030] After the closed slot section is formed, the joint box is pulled out so that the row plug end of the T-shaped steel cage of the closed slot section can be inserted into the socket of the row plug joint on that side.

[0031] 2) Production of T-type steel cage Under the background of existing technology, the main reinforcement connection of T-shaped steel cage can be mechanically connected. The spacing between the main reinforcements should be greater than 1000mm, and the number of joints in the same connection area should not exceed 50% of the total number; when processing the steel cage, the longitudinal and transverse reinforcements are connected by electric welding. A truss 32 is set in the steel cage, and the truss reinforcement is single-sided welded, with a length of not less than 10d. The joint positions should be staggered, and the percentage of welded joints in the same connection section should not be greater than 50%. The intersections of the longitudinal and transverse truss reinforcements need to be spot welded, and all the intersections within 0.5m around the steel cage need to be spot welded. The overlap misalignment and joint inspection should meet the requirements of reinforced concrete specifications. The steel bars are guaranteed to be straight, the surface is clean and oil-free, 50% of the internal intersections are spot welded, and 100% of the steel cage trusses and steel cage lifting points 1m above and below need to be spot welded. This production can well ensure the overall flatness of the steel cage without affecting the lifting.

[0032] The widths of the main steel cage and the row steel cage of the T-shaped steel cage are designed according to the width requirements of the main wall and the middle partition wall. The plug-in portion (the portion near the row plug end) 37 of the row steel cage is used to insert into the socket of the row plug joint (the space between the two wing plates on the same side and the steel mesh / transverse steel bars on the two wing plates). Its width is smaller than the width of the main part of the row steel cage to adapt to the socket requirements. Two horizontal reverse bends can be set on the transverse reinforcement to achieve the width change between the main body of the row steel cage and the plug-in portion.

[0033] The connection between the steel cages in the main wall (the main steel cage in the T-shaped steel cage) adopts a concave-convex flexible joint, with one end of the main steel cage set to be concave and the other end set to be convex. During construction, a joint pipe is placed outside the concave end 33 of the main steel cage of the T-shaped steel cage, and the joint pipe is pulled out after the adjacent slot sections are formed to allow the convex end 34 of the main steel cage of the T-shaped steel bars of the adjacent slot sections to be inserted, so as to realize the flexible connection of the two main steel cages through convex-concave matching.

[0034] The net protective layer of the main reinforcement of the steel cage can be set to 70mm or other thickness specified in the specification. A certain gap should be left between the end of the horizontal reinforcement and the joint box and the concrete joint surface. In order to ensure the thickness of the protective layer, a number of steel pads are set on the horizontal reinforcement. The center spacing of the steel pads is 3m, and there are no less than 2 pads on each surface of each row. The pads are made of 4mm thick flat steel. Other suitable methods can also be used to set the steel pads.

[0035] 3) Installation of steel cage (T-shaped steel cage) and socket connector 1) In order to ensure that the steel cage has a certain rigidity and prevent deformation during hanging, two inverted U-shaped reinforcement bars can be set at the hanging point, one hanging point and one cross bar point. The two ends of the reinforcement bars should be firmly welded to the longitudinal bars.

[0036] 2) The steel cage is hoisted as a whole at one time. When processing the steel cage, the hoisting points should be set according to the weight, size and hoisting method of the steel cage, and the hoisting should be carried out strictly in accordance with the contents of the hoisting plan to ensure safety during hoisting.

[0037] If it is the first slotting section, the strip connector should be hoisted at the same time.

[0038] If it is a closed slot section, you should first pull out the power strip connector.

[0039] 3) When the steel cage enters the slot, the center of the lifting point must be aligned with the center of the slot section. Be careful not to allow the crane arm to swing or other influences to cause the steel cage to swing laterally, so as to avoid collapse of the horizontal wall.

[0040] 4) After the steel cage is placed in the groove, check whether its top elevation meets the design requirements, and then fix it to the guide wall.

[0041] 5) If the steel cage cannot be inserted into the groove smoothly, it should be hoisted out again. After the cause is found and the fault is solved, it can be hoisted again and the groove should be repaired if necessary. The steel cage should not be forcibly inserted into the base groove in a free fall state, otherwise it will cause the steel cage to deform or the groove wall to collapse, and produce a large amount of sediment at the bottom of the groove.

[0042] 6) The steel cage is placed in the slot using a main crane / crane (for example, a 100-ton crawler crane) and an auxiliary crane (for example, a 60-ton crawler crane). After the main and auxiliary cranes lift the steel cage vertically off the ground, remove the auxiliary hook, align it with the slot section, and slowly lower it into the slot wall. When it reaches the top of the guide wall, use a steel shoulder pole to pass through the top of the steel cage and place it on the top of the guide wall. Then, hang the main hook on the lifting rod, lift the steel cage down to the designed elevation, and finally support the steel cage with a steel shoulder pole and place it on the top of the guide wall.

[0043] 7) For the first trench section, after the steel cage and the plug-in joint are hoisted, the joint box is hoisted and placed on the other side of the plug-in joint. The joint pipe is hoisted and placed on the outside of the concave end of the main steel cage. Gravel is backfilled into the gaps in the trench outside the joint box and the joint pipe respectively to avoid / block the lateral pressure generated during concrete pouring from causing the joint box, joint pipe or steel cage to move. The gravel particle size can be 10-15cm.

[0044] For the closed slot section, after the steel cage is hoisted, the joint pipe is hoisted and placed outside the concave end of the main steel cage. Gravel is backfilled into the slot gap outside the joint pipe to avoid / block the lateral pressure generated during concrete pouring from causing the joint box, joint pipe or steel cage to move. The crushed stone particle size can be 10-15cm.

[0045] In one instance, the steel cage of the 6m first opening width (double I-beams) weighs 9.5t. Multiple lifting points are set. The first one is located 1.5m downward from the top of the steel cage, with 2 lifting points set at the upper and lower parts respectively, and the main crane is responsible for the lifting; the second one is set 8m downward from the first one, with 2 lifting points set in the upper layer. The third one is set 3.0m downward from the second one, with 2 lifting points set at the upper part. The fourth one is set 8m downward from the third one, with 2 lifting points set at the upper part. The fifth one is set 5.0m downward from the fourth one, with 2 lifting points set at the upper part. The fourth and fifth ones are responsible for lifting by the auxiliary crane.

[0046] In one instance, at the position of the first main lifting ring, "["-shaped support bars are set, with a total of 4 bars welded to the longitudinal main bars. The main lifting ring adopts a "U"-shaped steel cage, and each lifting point and lifting ring adopts a Φ25 round steel, welded between two main bars. The single-sided welding length is not less than 10d or the double-sided welding length is not less than 5d. The weld seam is full and without cracks, and the bending shape is regular. The elevation of the lifting rings in the same row is basically the same, and there shall be no excessive difference. The second to fourth main lifting rings are made of Φ25 round steel by hot bending into a "Ji"-shape, and the two main bars at the position of the main lifting ring are double-sided welded at the intersection with the distribution bars. The lifting ring and the truss bars are fully welded, and the weld seam length shall not be less than 10d. The effective thickness of the weld seam shall not be less than 0.3 times the diameter of the main bar; the weld seam width shall not be less than 0.8 times the diameter of the main bar. At the intersection of the horizontal distribution bars and the main bars within 1 meter in all directions (up, down, left, and right) of the lifting point, double-sided spot welding shall be carried out. The transverse truss bars and the two sides of the main bars are spot welded.

[0047] The butt joint of the T-shaped steel cage: The two T-shaped steel cages corresponding to the two sides of the I-shaped steel are respectively called steel cage A and steel cage B. First, excavate the unit trench section A of steel cage A (which can be called the first excavated trench section), and lift steel cage A and the socket joint together to the set position in the unit trench section A. The trench length corresponding to the middle partition wall in the unit trench section A should be suitable for the placement of steel cage A (the socket steel cage of steel cage A) and the socket joint. The socket end of steel cage A is inserted into the corresponding side socket of the socket joint. The joint box is lifted and placed on the other side of the socket joint, inserted into the other side socket of the socket joint, and the gap on its outer side (the other side far from the socket steel cage of steel cage A) is filled. Then, the concrete pouring of trench section A is carried out. After the pouring is completed, excavate the unit trench section B of steel cage B (which can be called the closed trench section), pull out the joint box, lift steel cage B into the trench section B, and the socket end of steel cage B is inserted into the corresponding side socket of the socket joint. Thus, the socket steel cages of steel cage A and steel cage B are connected through the socket joint, forming the built-in steel bars of the middle partition wall. After setting the joint pipe and filling the gap, the concrete pouring of trench section B is carried out to complete the construction of the I-shaped wall.

[0048] Other matters regarding the processing and setting of the steel cage: 1) The steel cage is fabricated according to the reinforcement drawing of the diaphragm wall (such as the anti-scour wall) and the division of the unit trench section; 2) The main reinforcement of the wall is connected by mechanical connection method, which is implemented in accordance with the "General Technical Code for Mechanical Connection of Reinforcement" (JGJ107-2016). The spacing between the main reinforcement joints is greater than 1000mm, and the number of joints in the same connection area shall not exceed 50% of the total number; 3) If the wall is required to have embedded parts, the elevation error of the embedded parts shall not exceed 10mm; 4) The longitudinal main reinforcement at the lower end of the steel cage should be bent inward to prevent the steel bars from scratching the slot wall during hoisting, but the degree of inward bending should not affect the insertion of the conduit for pouring concrete; 5) When making the steel cage, the position of the conduit used for pouring concrete must be determined in advance. Since this part of the space needs to be connected from top to bottom, it can be reinforced by adding stirrups and connecting bars around it according to actual needs; 6) To prevent the steel bars from getting stuck in the conduit, the main longitudinal reinforcement should be placed on the inside and the horizontal reinforcement on the outside.

[0049] 7) The net protective layer of the main reinforcement of the steel cage is 70mm, and a certain gap should be left between the end of the horizontal reinforcement and the joint box and the concrete joint surface. To ensure the thickness of the protective layer, steel pads are placed on the horizontal reinforcements, with a center spacing of 3m, and no less than 2 pads per row and per surface. The pads are made of 4mm thick flat steel.

[0050] 8) For embedded parts in the wall (such as stress gauges, inclinometer tubes, water pressure gauges and other test components), they should be positioned as required and protected to ensure the survival rate of each test component.

[0051] 9) In order to prevent the concrete from flowing around during the pouring process, a slurry stop plate measure is proposed, that is, a thin iron sheet with a thickness of 0.2mm and a width of 1000mm is laid longitudinally on the wing plates on both sides of the I-beam near the steel bars, and is compacted and fixed to the I-beam with steel bars with a diameter of 10mm.

[0052] The construction process of the I-shaped wall (first slot section) mainly includes: 1) T-slot forming The trenching construction mainly adopts GB80S trenching machine (underground continuous wall hydraulic grab bucket) to form trenches, and the unit trench section is a T-shaped trench. Before trenching construction, first inject mud into the guide wall and position the hydraulic grab bucket at the trench section to be constructed. When grabbing the trench, the bucket teeth of the hydraulic grab bucket are fully opened and aligned with the edge line of the trench section, and grab it directly to the bottom of the trench; interval (jump amplitude) construction is adopted between the trenching of the unit trench section. The construction sequence in the unit trench section is the front end and the back middle. While trenching, the mud is added to the trench in time. After the trenching reaches the designed elevation, the machine is moved to start the bottom cleaning work. During the construction of the trench section, attention should be paid to controlling the verticality, controlling the position of the grab bucket through the guide groove, and adjusting the inclination of the grab bucket in time according to the computer display of the hydraulic trenching machine.

[0053] 2) Installation of steel cage, socket connector and connector box For the first slot section, first hoist the T-shaped steel cage and the row of plug connectors into the slot, and then hoist them into the joint box.

[0054] i) To ensure that the steel cage has a certain rigidity and prevent deformation during hanging, longitudinal truss bars are set on the steel cage, and two inverted U-shaped reinforcement bars are set at the hanging point, one for the hanging point and one fork bar point. Both ends of the reinforcement bars should be welded firmly to the longitudinal bars; ii) The steel cage and the strip connector are hoisted as a whole at one time. When processing the steel cage, the hoisting points should be set according to the weight, size and hoisting method of the steel cage, and the hoisting should be carried out strictly in accordance with the hoisting plan to ensure safety during hoisting.

[0055] iii) When the steel cage and the strip connector enter the slot, the center of the lifting point must be aligned with the center of the slot section. The crane arm should not swing or other influences should not cause the steel cage to swing laterally, so as to avoid the collapse of the horizontal wall.

[0056] iv) After the steel cage and the strip connectors are placed into the slot, check whether their top elevations meet the design requirements, and then fix them to the guide wall.

[0057] v) Method of placing the steel cage in the slot: Use a main crane / main crane (for example, a 100-ton crawler crane) and an auxiliary crane / crane (for example, a 60-ton crawler crane). After the main and auxiliary cranes lift the steel cage vertically off the ground, remove the auxiliary hook; the row plug connector is directly hoisted by a 100-ton crawler crane. Aim at the slot section position and slowly lower it into the slot wall. When it reaches the top surface of the guide wall, use a steel shoulder pole to pass through the top of the steel cage and place it on the top surface of the guide wall. Hang the main hook on the lifting rod, lift the steel cage down to the designed elevation, and finally use a steel shoulder pole to support the steel cage and place it on the top surface of the guide wall.

[0058] vi) After the steel cage and the strip joint are lowered, the joint box is lowered along the I-beam to the bottom of the anti-collision wall, and gravel is backfilled between the outer side (equivalent to the other side of the steel cage) and the groove wall to resist the lateral pressure on the joint generated when blocking the concrete pouring and prevent the steel cage from moving. The gravel particle size is 10-15cm.

[0059] 3) Concrete pouring i) First pour the concrete of the main wall (for example, anti-collision wall). When the middle partition wall conduit is buried 0.5m-1m below the concrete liquid surface, start pouring the cross partition wall and main wall concrete simultaneously.

[0060] ii) Concrete pouring must start within 4 hours after the bottom is cleaned and the slurry is replaced. The pouring derrick is erected firmly, and the conduit is placed in the slot of the central hole of the pouring derrick. A storage hopper is placed on the top of the conduit. The amount of concrete poured for the first time should ensure that the lower end of the conduit is buried in the concrete, and the buried depth of the conduit is not less than 2m. The pouring should be carried out continuously, and the height difference between any two points on the top surface of the concrete on both sides should not exceed 50cm. The rising speed of the concrete surface should be controlled at 3m / h~5m / h; the depth of the lower end of the conduit inserted into the concrete should be controlled at 2~6m. Use a measuring rope to measure the pouring depth in time, and lift the conduit in time during the pouring. Pour to 30cm above the designed top surface, pull out the conduit, and the pouring is completed.

[0061] iii) Concrete pouring should be continuous without long interruptions. Generally, an interruption of 5 to 10 minutes is allowed, and a maximum interruption of 20 to 30 minutes is allowed to ensure the uniformity of the concrete. After the concrete is mixed, pouring should be completed within 1.5 hours.

[0062] iv) During the pouring of concrete, the joint pipe should be prevented from bypassing. The pulling out of the joint pipe should be combined with the concrete pouring. The pulling out should start about 4 to 5 hours after the concrete pouring starts. After that, it should be lifted every 30 minutes, with the amplitude not exceeding 50 to 100 mm. The joint pipe should be pulled out 7 to 9 hours after the concrete pouring ends, that is, after the concrete reaches final setting.

[0063] After the first trench section is completed, the closed trench section construction is implemented. The specific steps and methods are basically the same as the first construction. The joint box on the socket of the plug connector needs to be pulled out and cleaned accordingly.

[0064] Unless otherwise specified or when one preferred or optional technical means is a further limitation of another technical means, the preferred and optional technical means disclosed in the present invention can be arbitrarily combined to form several different specific implementation methods.

Claims

1. I-shaped partition wall connection structure, characterized by It includes an I-shaped wall, which is composed of two main walls arranged in parallel and a middle partition wall located between the two main walls and perpendicular to the main walls, the two ends of the middle partition wall are respectively connected to the middle parts of the two main walls, and two T-shaped steel cages are arranged in the I-shaped wall, the T-shaped steel cage includes a main steel cage located in the main wall on the corresponding side and a row of steel cages located in the middle partition wall, a row of joints is provided between the row of steel cages of the two T-shaped steel cages, and the row of joints includes an I-beam, the I-beam is vertically arranged, and its two wing plates are parallel to the wall surface of the tie wall, and a steel mesh is respectively provided on the transverse sides of the wing plate, the steel mesh extends transversely from the corresponding side of the wing plate, and is overlapped on the outer side of the row of steel cages of the T-shaped steel cage on the corresponding side, and a plug-in part is provided on the row of steel cages of the T-shaped steel cage, and the plug-in part is inserted between the two wing plates of the I-beam of the corresponding row of joints and the two steel meshes extending from the two wing plates respectively.

2. The I-shaped partition wall connection structure according to claim 1, characterized in that The steel mesh is provided with a plurality of transverse bars distributed up and down, and may or may not be provided with longitudinal bars cross-connected with the transverse bars to form a mesh structure.

3. The I-shaped partition wall connection structure according to claim 2, characterized in that The inner ends of the steel mesh sheets are welded to the outer sides of the corresponding wing plates.

4. The I-shaped partition wall connection structure as claimed in claim 3, characterized in that The specifications and spacing of the transverse bars on the steel mesh are consistent with the specifications and spacing of the transverse bars on the row steel cage of the T-shaped steel cage.

5. The I-shaped partition wall connection structure according to claim 1, characterized in that Both wing plates of the I-beam are provided with stop grout plates, and the stop grout plates extend from at least one side of the wing plate.

6. The I-shaped partition wall connection structure according to claim 5, characterized in that The slurry-stopping piece is a rectangular thin iron sheet.

7. The I-shaped partition wall connection structure according to claim 1, characterized in that The main steel cage and the inserted steel cage of the T-shaped steel cage are both rectangular cage-shaped. The vertical position and span of the inserted steel cage correspond to the reinforced concrete section of the middle partition wall, and are used as steel bars for the reinforced concrete section of the middle partition wall. The middle partition wall is provided with a concrete section located above and / or below its reinforced concrete section, or the middle partition wall is not provided with a plain concrete section.

8. The I-shaped partition wall connection structure according to claim 7, characterized in that The row of T-shaped steel cages is provided with a plug-in portion for inserting a row of plug connectors, the width of the plug-in portion is smaller than the width of the main body of the row of steel cages, and a transition section with a gradually decreasing width is provided between the main body of the row of steel cages and the plug-in portion.

9. The construction method of the I-shaped partition wall connection structure according to claims 1 to 8, characterized in that For any I-shaped wall unit, it is divided into two T-shaped unit slot sections, the first opening and the closed slot. The first slot section is excavated first. After the slot is completed, the T-shaped steel cage and the plug connector are hoisted into the slot together. The plug end of the T-shaped steel cage is inserted between the two wing plates on the corresponding side of the I-beam of the plug connector. The joint box is hoisted into the slot outside the plug connector. The inner end of the joint box is inserted between the two wing plates on the corresponding side of the I-beam of the plug connector and rests on the waist plate of the I-beam. The joint pipe is hoisted to the main body of the T-shaped steel cage. In the groove outside the concave end of the steel cage, the inner side of the joint pipe is located in the concave shape of the facade, the groove gap at the outer end of the joint box is filled, the groove gap outside the joint pipe is filled, and concrete is poured. After the construction of the first grooving section is completed, the closed groove section is excavated. After the grooving is completed, the joint box is pulled out and the T-shaped steel cage is hoisted into the groove. The joint pipe is hoisted into the groove outside the concave end of the main steel cage of the T-shaped steel cage. The inner side of the joint pipe is located in the concave shape of the facade, the groove gap outside the joint pipe is filled, and concrete is poured.

10. The construction method of the I-shaped partition wall connection structure according to claim 9, characterized in that In the case where only one side of the strip connector is provided with a stop plate, this side is directed toward the T-shaped steel cage of the first slotted section.

Images