Open caisson top enclosure beam structure based on square hollow steel pipe combination

Abstract

The utility model relates to an open caisson top enclosure beam structure based on square hollow steel pipe combination, which is used for surrounding the periphery of the top of an open caisson and is characterized in that the enclosure beam structure is a square structure formed by sequentially connecting a first cross beam, a second cross beam, a third cross beam and a fourth cross beam, each cross beam comprises a plurality of square hollow steel pipes which are connected end to end; in every two adjacent cross beams, the two square hollow steel pipes of the front cross beam and the rear cross beam which are connected with the two cross beams are arranged in the mode that the inner side wall of the square hollow steel pipe in the front cross beam is connected with the end of the square hollow steel pipe in the rear cross beam in an opposite mode. A circle of square enclosure beam structure is arranged on the periphery of the top of the open caisson, so that the open caisson can be effectively prevented from inclining at an overlarge angle in the sinking process; the enclosure beam structure is formed by connecting the square hollow steel pipes, the construction speed is high, the enclosure beam structure can be repeatedly used after being dismantled, and cost reduction is facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of municipal engineering construction, in particular to a caisson top enclosure beam structure based on a combination of square hollow steel pipes. Background Art

[0002] As an important underground structure and deep-buried foundation, caisson is widely used in municipal, highway, railway and other projects. Caisson is prone to tilt during construction due to uneven underground rock and soil properties. After the caisson tilts, the traditional method is to control and adjust the excavation of the earth under the caisson blade, that is, to correct the tilt by adjusting the resistance at the bottom of the caisson.

[0003] However, in the actual construction process, the caisson often has a large tilt angle, which increases the difficulty of subsequent correction. Therefore, there is an urgent need for a protective structure that can prevent the caisson from tilting too much. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a caisson top enclosure beam structure based on a combination of square hollow steel pipes for preventing the caisson from tilting too much in an angle in view of the current state of the prior art.

[0005] The technical solution adopted by the utility model to solve the above-mentioned technical problems is: a caisson top guard beam structure based on a combination of square hollow steel pipes, which is used to surround the periphery of the top of the caisson, and is characterized in that: the guard beam structure is a square structure formed by sequentially connecting a first beam, a second beam, a third beam and a fourth beam, and each beam includes a plurality of square hollow steel pipes connected end to end; wherein, in two adjacent beams, the two square hollow steel pipes of the front beam and the rear beam that complete the connection of the two beams are both arranged as follows: the inner side wall of the square hollow steel pipe in the front beam and the end of the square hollow steel pipe in the rear beam are directly connected.

[0006] In order to enclose the caisson top guard beam structure into a square, the first crossbeam and the third crossbeam each include N sections of square hollow steel pipes, and the second crossbeam and the fourth crossbeam each include N-1 sections of square hollow steel pipes; the two ends of the second crossbeam are respectively connected to the inner walls of the first crossbeam and the third crossbeam, and the two ends of the fourth crossbeam are respectively connected to the inner walls of the first crossbeam and the third crossbeam; the width h1 of the square hollow steel pipe is one half of the length h2 of the square hollow steel pipe; wherein N is an integer greater than or equal to 2. For example: for a caisson with a diameter of 3 meters, a total of 26 hollow square tubes of 300*300*600 are required, and the side length of the square formed by the inner edge of the guardrail beam is 3600mm; for a caisson with a diameter of 2 meters, a total of 18 hollow square tubes of 300*300*600 are required, and the side length of the square formed by the inner edge of the guardrail beam is 2400mm; for a caisson with a diameter of 1 meter, a total of 6 hollow square tubes of 300*300*600 are required, and the side length of the square formed by the inner edge of the guardrail beam is 1200mm; inclined supports are used in caissons with diameters of 2 meters and 3 meters.

[0007] Preferably, a first gap is formed between the ends of two adjacent square hollow steel tubes on each cross beam, and a connecting mechanism connecting the first gap is provided on each cross beam and between adjacent square hollow steel tubes, the connecting mechanism comprising flat steel and bolts, the flat steel is laid on the top wall of the square hollow steel tube and covers a portion of the gap corresponding to the first gap, and the flat steels on both sides of the first gap are connected to the top wall of the corresponding square hollow steel tube by bolts respectively. After the flat steels on both sides of the first gap are connected to the top wall of the square hollow steel tube, the connection between adjacent square hollow steel tubes on each cross beam can be realized.

[0008] Preferably, the flat steel is laid on the side wall of the square hollow steel pipe and covers part of the first gap, and the flat steels on both sides of the first gap are connected to the side walls of the corresponding square hollow steel pipe respectively by bolts. After the flat steels on both sides of the first gap are connected to the side walls of the square hollow steel pipe, the connection between adjacent square hollow steel pipes on each crossbeam is further realized. The connection structure is arranged on the top wall and the side wall of the square hollow steel pipe, which is convenient for construction.

[0009] In order to increase the firmness of the connection between adjacent square hollow steel tubes, the flat steel includes a first flat steel and a second flat steel. Two first flat steels and a second flat steel are arranged parallel to each other on the top wall and the side wall of the square hollow steel tube. The first flat steel and the second flat steel have the same length and are provided with three bolts between the two adjacent square hollow steel tubes. The first flat steel is provided with one bolt in one of the square hollow steel tubes, and the second flat steel is provided with two bolts in the square hollow steel tube. In other words, the first flat steel and the second flat steel are arranged staggered.

[0010] Preferably, second gaps are formed between the ends of the square hollow steel tubes at both ends of the second beam and the inner walls of the square hollow steel tubes on the first beam and the third beam, respectively; second gaps are formed between the ends of the square hollow steel tubes at both ends of the fourth beam and the inner walls of the square hollow steel tubes on the first beam and the third beam, respectively; a connecting mechanism connecting the second gap is arranged between the two square hollow steel tubes corresponding to adjacent beams, and the connecting mechanism includes flat steel and bolts, the flat steel is erected on the top wall of the square hollow steel tube and covers part of the second gap, and the flat steels on both sides of the second gap are connected to the top wall of the square hollow steel tube by bolts.

[0011] Preferably, square plates for sealing the ends of the first beam and the third beam are welded to the outer ends of the square hollow steel pipes located at both ends of the first beam and the third beam; the flat steel is mounted on the side wall of the square hollow steel pipe and the square plate and covers part of the second gap, and the flat steel mounted on the side wall of the square hollow steel pipe is connected to the side wall of the square hollow steel pipe by bolts; the flat steel mounted on the square plate is connected to the square plate by bolts.

[0012] In order to prevent the retaining beam structure from being pushed by the inclined caisson and improve the stability of the retaining beam structure, the retaining beam structure also includes soil anchor rods inserted into the soil layer, and the soil anchor rods are connected to the bottom of each of the cross beams.

[0013] In order to facilitate the connection between the soil anchor rod and each of the cross beams, the retaining beam structure also includes an L-shaped steel bar for connecting the soil anchor rod and the cross beam, the L-shaped steel bar includes a horizontal section and a vertical section, the horizontal section is welded to the bottom of the cross beam, and the vertical section is welded to the soil anchor rod.

[0014] Preferably, the horizontal section is welded to the top of a square hollow steel tube on the crossbeam, and the square hollow steel tube is located close to the length center of the crossbeam.

[0015] In order to improve the connection strength of the guard beam structure, diagonal supports are set up at the right-angle turns between adjacent beams. The two ends of the diagonal supports are respectively overlapped on the two beams and form an angle of about 45 degrees with the two beams.

[0016] Compared with the prior art, the advantages of the utility model are: a circle of square guard beam structure is arranged on the periphery of the top of the caisson, which can effectively prevent the caisson from tilting at an excessive angle during the sinking process; the guard beam structure is connected by square hollow steel pipes, the construction speed is fast, and the guard beam structure can be reused after being dismantled, which is conducive to reducing costs; by measuring the distance between the caisson and the guard steel beam, the verticality of the caisson is fine-tuned by using the excavation construction inside the caisson to ensure that the verticality is within 1% to 2%, which is conducive to improving the construction progress, the excavation is simple and convenient, the sinking speed is uniform, and the caisson construction is in a controllable state. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a top view of the caisson top enclosure beam structure in the embodiment of the utility model;

[0018] Figure 2 for Figure 1 Schematic diagram of the connection of adjacent square hollow steel tubes in the middle crossbeam;

[0019] Figure 3 for Figure 1 Schematic diagram of the connection of adjacent square hollow steel pipes at the center corner;

[0020] Figure 4 for Figure 3 A schematic diagram of the structure from another angle;

[0021] Figure 5 This is a schematic diagram of the connection between the soil anchor rod and the square hollow steel pipe in the embodiment of the utility model;

[0022] Figure 6 for Figure 1 Schematic diagram of the exploded view of the middle diagonal support. DETAILED DESCRIPTION

[0023] The present invention will be described in further detail below in conjunction with the accompanying drawings.

[0024] like Figures 1 to 6 The figure shows a preferred embodiment of the utility model of the caisson top enclosure beam structure based on the combination of square hollow steel pipes 5. The caisson top enclosure beam structure surrounds the periphery of the top of the caisson 100. In this embodiment, it is a circular caisson 100 with a diameter of 3 meters, and the enclosure beam structure is square.

[0025] Specifically, the enclosure beam structure includes a first crossbeam 1, a second crossbeam 2, a third crossbeam 3 and a fourth crossbeam 4 connected in sequence. The first crossbeam 1 and the third crossbeam 3 each include 7 sections of square hollow steel pipes 5, and the second crossbeam 2 and the fourth crossbeam 4 each include 6 sections of square hollow steel pipes 5. The square hollow steel pipes 5 on each crossbeam are connected end to end; the two ends of the second crossbeam 2 are respectively connected to the inner side walls of the first crossbeam 1 and the third crossbeam 3, and the two ends of the fourth crossbeam 4 are respectively connected to the inner side walls of the first crossbeam 1 and the third crossbeam 3; wherein the height of the square hollow steel pipe 5 is 300 mm. Figure 1 As shown, the width h1 of the square hollow steel pipe 5 is 300 mm, and the length h2 of the square hollow steel pipe 5 is 600 mm; the outer side length of the overall enclosure beam structure is 4200 mm, and the inner side length is 3600 mm; the caisson is located at the center of the enclosure beam structure, and the shortest distance h3 between the first beam 1, the second beam 2, the third beam 3 and the fourth beam 4 and the caisson 100 is 300 mm.

[0026] like Figure 1 , 2 As shown, a first gap 51 is formed between the ends of adjacent square hollow steel tubes 5 on each cross beam, and a connecting mechanism 6 connecting the first gap 51 is provided between adjacent square hollow steel tubes 5 on each cross beam, and the connecting mechanism 6 includes a flat steel 61 and a bolt 62. Specifically, the flat steel 61 is laid on the top wall of the square hollow steel tube 5 and covers part of the first gap, and the flat steel 61 on both sides of the first gap 51 is respectively connected to the top wall of the square hollow steel tube 5 by bolts 62; in addition, the flat steel 61 is laid on the side wall of the square hollow steel tube 5 and covers part of the first gap 51, and the flat steel 61 on both sides of the first gap 51 is respectively connected to the side wall of the square hollow steel tube 5 by bolts 62.

[0027] In order to increase the firmness of the connection between adjacent square hollow steel tubes 5, the flat steel 61 includes a first flat steel and a second flat steel. Two first flat steels and a second flat steel arranged parallel to each other are arranged on the top wall and the side wall of the square hollow steel tube 5. The first flat steel and the second flat steel have the same length and three bolts 62 are arranged between the two adjacent square hollow steel tubes 5. The first flat steel is provided with one bolt 62 on the square hollow steel tube 5 on the first side of the first gap 51, and two bolts 62 are arranged on the square hollow steel tube 5 on the second side of the first gap 51; the second flat steel is provided with two bolts 62 on the square hollow steel tube 5 on the first side of the first gap 51, and one bolt 62 is arranged on the square hollow steel tube 5 on the second side of the first gap 51.

[0028] like Figure 1 , 3As shown in Figure 4, the end portions of the square hollow steel tubes 5 at both ends of the second crossbeam 2 form second gaps 52 with the inner walls of the square hollow steel tubes 5 on the first crossbeam 1 and the third crossbeam 3, respectively. The end portions of the square hollow steel tubes 5 at both ends of the fourth crossbeam 4 also form second gaps 52 with the inner walls of the square hollow steel tubes 5 on the first crossbeam 1 and the third crossbeam 3, respectively. A connecting mechanism 6 connecting the second gap 52 is provided between the two square hollow steel tubes 5 correspondingly connected to adjacent crossbeams, and the connecting mechanism 6 includes a flat steel 61 and a bolt 62. Specifically, the flat steel 61 is mounted on the top wall of the square hollow steel tube 5 and covers part of the second gap 52. Bolts 62 are used on the flat steels 61 on both sides of the second gap 52 to connect the flat steel 61 to the top wall of the square hollow steel tube 5; in addition, the outer ends of the square hollow steel tube 5 located at both ends of the first beam 1 and the third beam 3 are welded with square plates for sealing the ends of the first beam 1 and the third beam 3. The thickness of the square plate 9 is 3 mm. The four sides of the square plate 9 are welded to the inner wall of the square hollow steel tube 5. Bolt holes are provided on the square plate 9, and bolts are welded in the bolt holes, and the bolts are in a fixed state; the flat steel 61 is mounted on the side wall of the square hollow steel tube 5 and the square plate 9 and covers part of the second gap 52. The flat steel 61 mounted on the side wall of the square hollow steel tube 5 is connected to the side wall of the square hollow steel tube 5 by bolts 62; the flat steel 61 mounted on the square plate 9 is also connected to the square plate 9 by bolts 62. The flat steel 61 also includes two parallel flat steels, a first flat steel and a second flat steel, which are also staggered. The first flat steel is connected to two bolts 62 on the first side of the second slit 52 and one bolt 62 on the second side of the second slit 52; the second flat steel is connected to one bolt 62 on the first side of the second slit 52 and two bolts 62 on the second side of the second slit 52.

[0029] In this embodiment, when installing or removing the flat steel and bolts 62 on the outer surface of each beam, the soil at the corresponding position can be hollowed out for easy operation. In addition, the present application sets a 3 mm thick lining steel plate at the bolt hole position inside the square hollow steel pipe, and the lining steel plate is set in the following manner: first, insert the bolt into the bolt hole of the outer wall, and one end of the nut to be tightened on the bolt is exposed outside the square hollow steel pipe; then place the lining steel plate parallel to the outer wall, and the spacing between the lining steel plate and the outer wall of the square hollow steel pipe is 30 mm, which can prevent the bolt from falling out of the bolt hole and thus half-fix the bolt in the bolt hole; then weld the upper and lower ends of the lining steel plate to the top wall and bottom wall of the square hollow steel pipe respectively; and then use the same method to set the lining steel plate parallel to the top wall of the square hollow steel pipe, the only difference being that the outer end of the lining steel plate is welded to the lining steel plate parallel to the outer wall. The left and right ends of the inner lining steel plate do not extend beyond the square hollow steel pipe. More preferably, the length of the inner lining steel plate is 15 mm shorter than the length of the square hollow steel pipe. The bolt 62 is exposed from the square hollow steel pipe, and it is inconvenient to tighten the bolt 62 and the nut. After the inner lining steel plate is installed, the bolt will not fall out of the bolt hole, which is convenient for repeated disassembly and assembly of adjacent square hollow steel pipes.

[0030] like Figure 5 As shown, the bottom of the square hollow steel pipe 5 located near the center of the length of each cross beam is connected with a soil anchor rod 7, and there are 4 soil anchor rods in total; the soil anchor rod 7 is vertically inserted into the soil layer; the top of the soil anchor rod 7 is connected to the bottom of the square hollow steel pipe 5 through an L-shaped steel bar 8, and the L-shaped steel bar 8 includes a horizontal section 81 and a vertical section 82, the horizontal section 81 is welded to the bottom of the square hollow steel pipe 5, and the vertical section 82 is welded to the soil anchor rod 7. In other embodiments, the soil anchor rod can also be obliquely inserted into the soil layer, forming an angle of 25 degrees with the ground plane, and the top of the soil anchor rod 7 is connected to the top of the square hollow steel pipe 5. Figure 1 , 6 As shown, an inclined support 200 is set up at the right-angle turn between adjacent beams, and the two ends of the inclined support 200 are respectively overlapped on the two beams, and the angle between the two beams is about 45 degrees; the structure of the inclined support 200 is similar to that of the square hollow steel pipe in the beam, but it is longer. The inclined support 200 in this embodiment is connected by two 300*300 square hollow steel pipes with a length of 1400 mm. Among them, the two square hollow steel pipes on the inclined support 200 are connected by a square hollow steel pipe with a size of 280*280, and the square hollow steel pipe of 280*280 is set inside the connection of the two 300*300 square hollow steel pipes, and the overlapped part of the 280*280 square hollow steel pipe and the 300*300 square hollow steel pipe is connected by bolts.

[0031] like Figure 1As shown in the figure, when the caisson is not tilted, the distance between the caisson and the surrounding steel beam is h3, that is, 300 mm. By measuring the h3 between the caisson and the surrounding beam, h3 is controlled within the range of 30 mm; when the first section of the caisson sinks 50%, the inclination is 2%, and when it sinks 100%, the inclination is 1%. The control of the inclination speeds up the sinking speed and reduces the side wall friction. When the soil in the well accumulates to a certain height, the sinking stops. It is only necessary to evenly dig out the thickness of the accumulated soil, so that the sinking depth and the thickness of the excavated soil are equal. When the caisson construction is terminated, the elevation reaches the sea level specified in the design and is in a controllable state. This can control the excavation speed and is safer. The distance between the caisson and the guardrail beam can be measured by a ruler plus a red flag. The ruler is measured in two adjacent directions perpendicular to the four sides. When h3 exceeds the range of 30 mm, the direction is turned so that the red flag is in a visible position in the caisson. After hearing the order, the construction workers digging in the caisson will dig in the direction opposite to the red flag to make it sink slightly. After fine-tuning, the inclination is between 1% and 2%.

Claims

1. A caisson top guard beam structure based on a combination of square hollow steel pipes, used to surround the periphery of the top of the caisson (100), characterized in that: The enclosure beam structure is a square structure formed by sequentially connecting a first crossbeam (1), a second crossbeam (2), a third crossbeam (3) and a fourth crossbeam (4), each crossbeam comprising a plurality of square hollow steel tubes (5) connected end to end; wherein, in two adjacent crossbeams, the two square hollow steel tubes (5) of the front crossbeam and the rear crossbeam that complete the connection of the two crossbeams are both arranged such that the inner side wall of the square hollow steel tube (5) in the front crossbeam and the end of the square hollow steel tube (5) in the rear crossbeam are arranged opposite to each other and connected.

2. The caisson top enclosure beam structure according to claim 1 is characterized in that: The first crossbeam (1) and the third crossbeam (3) each include N sections of square hollow steel tubes (5), and the second crossbeam (2) and the fourth crossbeam (4) each include N-1 sections of square hollow steel tubes (5); the two ends of the second crossbeam (2) are respectively connected to the inner side walls of the first crossbeam (1) and the third crossbeam (3), and the two ends of the fourth crossbeam (4) are respectively connected to the inner side walls of the first crossbeam (1) and the third crossbeam (3); the width h1 of the square hollow steel tube (5) is half of the length h2 of the square hollow steel tube (5); wherein N is an integer greater than or equal to 2.

3. The caisson top enclosure beam structure according to claim 2 is characterized in that: A first gap (51) is formed between the ends of two adjacent square hollow steel tubes (5) located on each cross beam, and a connecting mechanism (6) connecting the first gap (51) is provided on each cross beam and between adjacent square hollow steel tubes (5). The connecting mechanism (6) comprises a flat steel (61) and a bolt (62). The flat steel (61) is laid on the top wall of the square hollow steel tube (5) and covers a portion of the corresponding first gap (51). The flat steel (61) on both sides of the first gap (51) is connected to the top wall of the corresponding square hollow steel tube (5) by bolts (62) respectively.

4. The caisson top enclosure beam structure according to claim 3 is characterized in that: The flat steel (61) is mounted on the side wall of the square hollow steel pipe (5) and covers part of the first gap (51); the flat steel (61) on both sides of the first gap (51) is connected to the side wall of the corresponding square hollow steel pipe (5) by bolts (62) respectively.

5. The caisson top enclosure beam structure according to claim 4 is characterized in that: The flat steel (61) comprises a first flat steel and a second flat steel. Two pieces of the first flat steel and the second flat steel are arranged parallel to each other on the top wall and the side wall of the square hollow steel tube (5). The first flat steel and the second flat steel have the same length and three bolts (62) are arranged between two adjacent square hollow steel tubes (5). The first flat steel is provided with one bolt (62) in one of the square hollow steel tubes (5), and the second flat steel is provided with two bolts (62) in the square hollow steel tube (5).

6. The caisson top enclosure beam structure according to claim 2, characterized in that: A second gap (52) is formed between the ends of the square hollow steel tubes (5) at both ends of the second crossbeam (2) and the inner side walls of the square hollow steel tubes (5) on the first crossbeam (1) and the third crossbeam (3), and a second gap (52) is formed between the ends of the square hollow steel tubes (5) at both ends of the fourth crossbeam (4) and the inner side walls of the square hollow steel tubes (5) on the first crossbeam (1) and the third crossbeam (3); a connecting mechanism (6) for connecting the second gap (52) is provided between two square hollow steel tubes (5) correspondingly connected to adjacent crossbeams, and the connecting mechanism (6) comprises a flat steel (61) and a bolt (62); the flat steel (61) is laid on the top wall of the square hollow steel tube (5) and covers part of the second gap (52); the flat steels (61) on both sides of the second gap (52) are connected to the top wall of the square hollow steel tube (5) by bolts (62) respectively.

7. The caisson top enclosure beam structure according to claim 6 is characterized in that: The outer ends of the square hollow steel tubes (5) located at both ends of the first crossbeam (1) and the third crossbeam (3) are welded with square plates (9) for sealing the ends of the first crossbeam (1) and the third crossbeam (3); the flat steel (61) is mounted on the side wall of the square hollow steel tube (5) and the square plate (9) and covers part of the second gap (52); the flat steel (61) mounted on the side wall of the square hollow steel tube (5) is connected to the side wall of the square hollow steel tube (5) by bolts (62); the flat steel (61) mounted on the square plate (9) is connected to the square plate (9) by bolts (62).

8. The caisson top enclosure beam structure according to any one of claims 1 to 7, characterized in that: It also comprises a soil anchor rod (7) inserted into the soil layer, wherein the soil anchor rod (7) is connected to the bottom of each of the cross beams.

9. The caisson top enclosure beam structure according to claim 8, characterized in that: It also includes an L-shaped steel bar (8) for connecting the soil anchor rod (7) and the cross beam, the L-shaped steel bar (8) including a horizontal section (81) and a vertical section (82), the horizontal section (81) is welded to the bottom of the cross beam, and the vertical section (82) is welded to the soil anchor rod (7); the horizontal section (81) is welded to the bottom of a square hollow steel pipe (5) on the cross beam, and the square hollow steel pipe (5) is located close to the length center of the cross beam.

10. The caisson top enclosure beam structure according to claim 1, characterized in that: An oblique support (200) is provided at the right-angle turning point between adjacent cross beams, and two ends of the oblique support (200) are respectively overlapped on the two cross beams and form an angle of about 45 degrees with the two cross beams.

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