Deepwater foundation pit fore shaft steel pipe pile cofferdam

Abstract

The utility model belongs to the technical field of steel sheet pile cofferdams, and particularly relates to a deepwater foundation pit fore shaft steel pipe pile cofferdam. Comprising a steel pipe pile cofferdam, and a plurality of sets of supporting frames arranged in an up-down layered mode are installed in the steel pipe pile cofferdam; the supporting frame comprises a circle of surrounding purlins installed on the inner wall of the steel pipe pile cofferdam. Diagonal braces are arranged between the planes of the enclosing purlins, angle braces are arranged at four corners of a rectangle defined by the enclosing purlins, and vertical joints are arranged between the supporting frames of the upper layer and the lower layer; according to the deepwater foundation pit fore shaft steel pipe pile cofferdam, the multiple supporting frames are arranged in the steel pipe pile cofferdam up and down at equal intervals, the supporting frames are vertically connected to form a whole, external water pressure is effectively resisted, and inward compression and overall inclination of the steel pipe pile cofferdam are prevented.

Description

Technical Field

[0001] The utility model belongs to the technical field of steel sheet pile cofferdams, and in particular relates to a deep water foundation pit locking steel pipe pile cofferdam. Background Art

[0002] Steel sheet pile cofferdam is currently a very advantageous deep-water foundation cofferdam construction technology. It is widely used in bridge construction and can solve the waterproofing problem in bridge construction, thereby ensuring the excellent quality of engineering construction. It has the advantages of simple structure, easy insertion, low cost, easy control, short construction period, and reusability. At present, steel sheet pile steel cofferdams are mostly used in bridge construction. They cannot support the foundation pit well under construction conditions with large water flow and deep insertion depth, and need repeated reinforcement. Therefore, it is urgent to design an underwater steel cofferdam structure to solve the above-mentioned problems, thereby improving construction quality and efficiency. Utility Model Content

[0003] An object of the present invention is to solve at least the above problems and to provide at least the advantages which will be described below.

[0004] The utility model provides the following technical scheme: a deep-water foundation pit locking steel pipe pile cofferdam, comprising a steel pipe pile cofferdam, wherein a plurality of groups of support frames arranged in upper and lower layers are installed in the steel pipe pile cofferdam; the support frames comprise purlins installed on a circle of the inner wall of the steel pipe pile cofferdam; braces are arranged between the planes of the purlins, corner braces are arranged at the four corners of the rectangle surrounded by the purlins, and vertical connections are arranged between the upper and lower support frames.

[0005] Furthermore, the braces are connected between two purlins forming the long sides of the rectangle, and the braces include a middle brace at the midpoint of the purlin and side braces symmetrically arranged on both sides of the middle brace; auxiliary braces are connected between the middle brace and the purlins at both ends.

[0006] Furthermore, the corner brace includes a long corner brace and a short corner brace, and a long corner brace and a short corner brace are arranged at each corner of the rectangle surrounded by the purlin, and the long corner brace and the short corner brace are parallel.

[0007] Further, the vertical connection includes a first vertical connection between the middle braces and a second vertical connection between the long angle braces; the first vertical connection includes a vertical rod and an oblique rod, the vertical rod and the oblique rod are connected between the middle braces, there is a pair of oblique rods between every two vertical rods, the first ends of the two oblique rods are respectively connected to the first ends of the two vertical rods, and the second ends of the two oblique rods are connected at the midpoint between the second ends of the two vertical rods;

[0008] The structure of the second vertical connection is the same as that of the first vertical connection, and the vertical rods and diagonal rods in the second vertical connection are connected between the long angle braces.

[0009] Furthermore, a thrust stopper is installed on the side of the purlin facing the steel pipe pile cofferdam, and the thrust stopper is stopped in the gap between the pile bodies of the steel pipe pile cofferdam.

[0010] Furthermore, steel plate corner stiffening ribs are installed at the four corners of the rectangle formed by the surrounding purlins, and the oblique sides of the steel plate corner stiffening ribs are parallel to the long angle braces and the short angle braces.

[0011] Furthermore, a corbel is welded to the inner wall of the steel pipe pile cofferdam, and the surrounding purlin is welded to the corbel.

[0012] Furthermore, both ends of the long angle brace and the short angle brace are connected to the oblique brackets on the steel pipe pile cofferdam.

[0013] Furthermore, the cross section of the thrust step is an isosceles right triangle, and the hypotenuse of the isosceles right triangle is connected to the surrounding purlin.

[0014] Furthermore, the included angles between the long angle brace and the short angle brace and the surrounding purlin are all 45 degrees.

[0015] Compared with the prior art, the advantages of the present invention are:

[0016] The utility model provides a deep-water foundation pit locking steel pipe pile cofferdam, in which a plurality of support frames are arranged at equal intervals in the upper and lower parts of the steel pipe pile cofferdam, and the support frames are vertically connected to form a whole, which effectively resists external water pressure and prevents the steel pipe pile cofferdam from being compressed inwardly and tilted as a whole; the braces on the support frames provide support force for the long sides of the support frames; the angle braces on the support frames provide support force for the short sides and long sides of the support frames, and prevent the support frames from twisting and deforming; the thrust pedals on the support frames prevent the support frames from rubbing as a whole relative to the steel pipe pile cofferdam; the entire support frame system is reasonably stressed and has no redundant rods. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the utility model;

[0018] Figure 2 It is a schematic diagram of the positions of the first supporting frame, the second supporting frame, and the third supporting frame;

[0019] Figure 3 is a schematic diagram of the first vertical connection;

[0020] Figure 4 is a schematic diagram of the second vertical connection;

[0021] Figure 5 Schematic diagram of the push pedal.

[0022] In the figure: 1- steel pipe pile cofferdam; 2- surrounding purlin; 3- middle brace; 4- side brace; 5- auxiliary brace; 6- long angle brace; 7- short angle brace; 8- steel plate corner stiffener; 9- first vertical connection; 9.1- vertical pole; 9.2- diagonal pole; 10- second vertical connection; 11- thrust pedal; 12- diagonal corbel; 13- first supporting frame; 14- second supporting frame; 15- third supporting frame; H- top elevation of pedestal. DETAILED DESCRIPTION

[0023] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] like Figure 1 , Figure 2 As shown: a deep-water foundation pit locking steel pipe pile cofferdam, comprising a steel pipe pile cofferdam 1, in which a plurality of groups of support frames arranged in upper and lower layers are installed; the support frame comprises a purlin 2 installed on a circle of the inner wall of the steel pipe pile cofferdam 1; a corbel is welded to the inner wall of the steel pipe pile cofferdam 1, and the purlin 2 is welded to the corbel; a butt brace is arranged between the planes of the purlin 2, and corner braces are arranged at the four corners of the rectangle surrounded by the purlin 2, and a vertical connection is arranged between the upper and lower support frames.

[0025] In this embodiment, three support frames are used in the steel pipe pile cofferdam 1, and the three support frames are all located above the top elevation of the pedestal; the spacing between the three support frames is equal, and the spacing between the three support frames is 3.5m.

[0026] The braces are connected between two purlins 2 forming the long sides of the rectangle, and include a middle brace 3 at the midpoint of the purlin 2 and side braces 4 symmetrically arranged on both sides of the middle brace 3; auxiliary braces 5 are connected between the middle brace 3 and the purlins 2 at both ends.

[0027] The angle brace includes a long angle brace 6 and a short angle brace 7. A long angle brace 6 and a short angle brace 7 are arranged at each corner of the rectangle surrounded by the purlin 2. The long angle brace 6 and the short angle brace 7 are parallel. The angles between the long angle brace 6 and the short angle brace 7 and the purlin 2 are both 45°. The two ends of the long angle brace 6 and the short angle brace 7 are welded to the oblique bracket 12 on the steel pipe pile cofferdam 1.

[0028] The four corners of the rectangle formed by the surrounding purlin 2 are installed with steel plate corner stiffening ribs 8, and the oblique sides of the steel plate corner stiffening ribs 8 are parallel to the long angle brace 6 and the short angle brace 7.

[0029] like Figure 3As shown: the vertical connection includes a first vertical connection 9 between the middle braces 3 and a second vertical connection 10 between the long angle braces 6; the first vertical connection 9 includes a vertical rod 9.1 and an inclined rod 9.2, the vertical rod 9.1 and the inclined rod 9.2 are connected between the middle braces 3, there is a pair of inclined rods 9.2 between every two vertical rods 9.1, the first ends of the two inclined rods 9.2 are respectively connected to the first ends of the two vertical rods 9.1, and the second ends of the two inclined rods 9.2 are connected at the midpoint between the second ends of the two vertical rods 9.1.

[0030] In this embodiment, the first vertical connections 9 on both sides of the middle support 3 on the second support frame 14 are mirror images of each other.

[0031] like Figure 4 As shown: the structure of the second vertical connection 10 is the same as that of the first vertical connection 9 , and the vertical rods and diagonal rods in the second vertical connection 10 are connected between the long angle braces 6 .

[0032] In this embodiment, the second vertical connections 10 on both sides of the long angle braces 6 on the second support frame 14 are mirror images of each other.

[0033] like Figure 5 As shown: a thrust stopper 11 is installed on the side of the purlin 2 facing the steel pipe pile cofferdam 1, and the thrust stopper 11 is stopped in the pile body gap of the steel pipe pile cofferdam 1, and the thrust stopper 11 prevents the purlin 2 from lateral rubbing.

[0034] The cross section of the thrust step 11 is an isosceles right triangle, and the hypotenuse of the isosceles right triangle is connected to the surrounding purlin 2 .

[0035] The steel pipe piles are driven one by one using a 90T hydraulic vibrating hammer. After the steel pipe piles are connected, the first supporting frame 13 is installed. First, the corbels are welded to the steel pipe piles; then the surrounding purlins 2 are hoisted and placed on the corbels and welded firmly, and the steel plate corner stiffening ribs 8 are welded properly in time; to facilitate the hoisting of the surrounding purlins on the second and third supporting frames, before installing the angle braces and opposite braces of the first supporting frame 13, the surrounding purlins of the second and third supporting frames need to be hoisted into the steel pipe pile cofferdam 1; finally, the angle braces and opposite braces are installed.

[0036] The specific construction steps of the steel pipe pile cofferdam and support frame are:

[0037] Step 1: After the bored pile construction is completed, evacuate the drilling rig and clean the drilling construction platform;

[0038] Step 2: After the steel pipe piles are transported to the construction site, they are inspected in detail. If they are qualified, the steel pipe pile locks are welded. The lock buckle uses a φ180×8mm steel pipe, and the lock arm uses 20#a I-beam;

[0039] Step 3: Set control measurement points on the steel platform and steel trestle at a certain distance from the cofferdam. Before installing the guide beam, use the total station to measure and lay out the inner contour of the cofferdam; during the insertion and driving of the interlocking steel pipe piles, use the front intersection method of two total stations to control the verticality of the interlocking steel pipe piles;

[0040] Step 4: Install the guide frame on the casing and drive the locking piles one by one;

[0041] Step 5: The excavator digs the riverbed covering soil layer on the platform channel side and loads it onto trucks for transportation, while maintaining internal and external water pressure balance;

[0042] Step 6: Install the corbels and the first purlin of the supporting frame;

[0043] Step 7: Pour underwater bottom seal concrete into the conduit, and after pouring, cut off the casing above the top surface of the bottom seal concrete;

[0044] Step 8: Pump water to 1m below the installation height of the second support frame, and install the corbels and purlins;

[0045] Step 9: Continue pumping water to 1m below the installation height of the third support frame, and install the corbels and purlins;

[0046] Step 10: Complete the welding of the angle braces and butt braces in the third support frame, the second support frame, and the first support frame in sequence; and complete the welding of the vertical connections between the third support frame, the second support frame, and the first support frame.

[0047] Level 2 welds are used for purlins, corner braces, braces, vertical connections and oblique corbels, and level 3 welds are used for the remaining welds. Level 2 welds require random inspection of "20% of the length of each weld" and ultrasonic testing of no less than 200mm. The welds must be smooth, full, and free of burrs and flying burrs.

[0048] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A deep-water foundation pit locking steel pipe pile cofferdam, characterized by: The invention comprises a steel pipe pile cofferdam (1), wherein a plurality of groups of support frames arranged in upper and lower layers are installed in the steel pipe pile cofferdam (1); the support frames comprise purlins (2) installed on a circle of the inner wall of the steel pipe pile cofferdam (1); braces are arranged between the planes of the purlins (2), corner braces are arranged at the four corners of the rectangle formed by the purlins (2), and vertical connections are arranged between the upper and lower support frames.

2. A deep-water foundation pit locking steel pipe pile cofferdam according to claim 1, characterized in that: The brace is connected between two purlins (2) forming the long sides of the rectangle, and comprises a middle brace (3) at the midpoint of the purlin (2) and side braces (4) symmetrically arranged on both sides of the middle brace (3); auxiliary braces (5) are connected between the middle brace (3) and the purlins (2) at both ends.

3. A deep-water foundation pit locking steel pipe pile cofferdam according to claim 2, characterized in that: The corner brace comprises a long corner brace (6) and a short corner brace (7). A long corner brace (6) and a short corner brace (7) are arranged at each corner of a rectangle formed by the purlin (2). The long corner brace (6) and the short corner brace (7) are parallel.

4. A deep-water foundation pit locking steel pipe pile cofferdam according to claim 3, characterized in that: The vertical connection comprises a first vertical connection (9) between the middle braces (3) and a second vertical connection (10) between the long angle braces (6); the first vertical connection (9) comprises a vertical rod (9.1) and an inclined rod (9.2), the vertical rod (9.1) and the inclined rod (9.2) are connected between the middle braces (3), there is a pair of inclined rods (9.2) between every two vertical rods (9.1), the first ends of the two inclined rods (9.2) are respectively connected to the first ends of the two vertical rods (9.1), and the second ends of the two inclined rods (9.2) are connected at the midpoint between the second ends of the two vertical rods (9.1); The structure of the second vertical connection (10) is the same as that of the first vertical connection (9), and the vertical rods and diagonal rods in the second vertical connection (10) are connected between the long angle braces (6).

5. A deep-water foundation pit locking steel pipe pile cofferdam according to any one of claims 1 to 4, characterized in that: A thrust stopper (11) is installed on the side of the purlin (2) facing the steel pipe pile cofferdam (1), and the thrust stopper (11) is stopped in the gap between the pile bodies of the steel pipe pile cofferdam (1).

6. The deepwater foundation pit locking steel pipe pile cofferdam according to claim 3, characterized in that: The four corners of the rectangle formed by the surrounding purlin (2) are installed with steel plate corner stiffening ribs (8), and the oblique sides of the steel plate corner stiffening ribs (8) are parallel to the long angle brace (6) and the short angle brace (7).

7. The deepwater foundation pit locking steel pipe pile cofferdam according to claim 1, characterized in that: The inner wall of the steel pipe pile cofferdam (1) is welded with a corbel, and the surrounding purlin (2) is welded to the corbel.

8. The deepwater foundation pit locking steel pipe pile cofferdam according to claim 3, characterized in that: The two ends of the long angle brace (6) and the short angle brace (7) are connected to the oblique brackets (12) on the steel pipe pile cofferdam (1).

9. The deepwater foundation pit locking steel pipe pile cofferdam according to claim 5, characterized in that: The cross section of the thrust step (11) is an isosceles right triangle, and the hypotenuse of the isosceles right triangle is connected to the surrounding purlin (2).

10. The deepwater foundation pit locking steel pipe pile cofferdam according to claim 3, characterized in that: The included angles between the long angle brace (6) and the short angle brace (7) and the surrounding purlin (2) are both 45 degrees.

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