Adjustable assembled guide positioning frame for burying steel casing and operation method thereof

Abstract

The present invention discloses an adjustable assembled guide positioning frame and an operation method for burying steel casing. The positioning frame is composed of two groups of Bailey sheet groups, two outer upper beams, two inner upper beams, two lower beams and cross braces, and has the following advantages: first, the adjustable assembled guide positioning frame is set for positioning, which can reduce the deviation of steel casing burying, and part of the steel casing can be reused, which not only improves the construction quality of bored piles, but also saves resources; second, the deviation of steel casing is adjusted during construction by using the existing completed steel casing, pile foundation and bridge pier, which is scientific and reasonable; third, the calculation method provided has clear principles, is practical and easy to implement, and can be used as a guide for steel casing construction, improving safety and quality performance. Therefore, the positioning frame of the present invention has the advantages of simple structure, convenient construction, adjustable positioning accuracy, low cost, safety and reliability, and reusable resources. It can bring higher economic and social benefits when combined with the corresponding operation method.

Description

Technical Field

[0001] The invention relates to the field of bridge foundation construction, and in particular to an adjustable assembled guide positioning frame for burying a steel casing and an operation method thereof. Background Art

[0002] The construction of bored pile foundation for bridges on soft soil foundation requires pre-embedded steel casing, and the pre-embedded accuracy of steel casing is related to the accuracy of pile foundation positioning. For long or extra-long bored piles, the steel casing in the soft soil is generally left unpulled, while the underwater steel casing above the soft soil surface needs to be cut and removed and returned to the factory for reprocessing before reuse. In order to save steel, the steel casing is usually made into two sections, namely the upper casing and the lower casing, which are connected by a socket joint. After the bored pile concrete is poured, the upper casing in the soft soil can be pulled out in time. However, since the matching tolerance of the socket joints of the two sections of steel casing is very small, higher positioning accuracy is required to meet construction needs. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide an adjustable assembled guide positioning frame and operation method for burying steel casing with simple structure, convenient construction, adjustable positioning accuracy, low cost, safety and reliability, and reusable resources.

[0004] The technical problem of the present invention is achieved through the following technical solutions:

[0005] The invention discloses an adjustable assembled guide positioning frame for burying steel casing, which is installed on a soft soil foundation and used for accurately positioning and fixing the lower casing of the steel casing. The lower casing is then constructed on the soft soil foundation by a vibrating hammer, and the bottom end of the upper casing of the steel casing is connected to the top end of the lower casing through a socket joint; the soft soil foundation comprises a lower soft soil layer and a surface solidified soil layer, and the positioning frame comprises two groups of Bailey sheet rows arranged in parallel in the transverse direction, four upper crossbeams which are parallel to each other and arranged longitudinally across the tops of the two groups of Bailey sheet rows, and two lower crossbeams which are parallel to each other and arranged longitudinally across the bottoms of the two groups of Bailey sheet rows, so as to achieve a desired effect. and a cross brace connected to each other between the two groups of Bailey sheet rows; the two outer upper cross beams are fixedly connected to the tops of the two spanning Bailey sheet rows, the two inner upper cross beams are movably connected to the tops of the two spanning Bailey sheet rows, and the two lower cross beams are fixedly connected to the bottoms of the two spanning Bailey sheet rows; the two groups of Bailey sheet rows are respectively arranged on both sides of the steel casing; the lower casing is constructed on the soft soil foundation by sequentially passing through the two inner movable upper cross beams and the two fixed lower cross beams, and the two lower cross beams clamp and fix the lower casing, and the two inner upper cross beams adjust and clamp the lower casing.

[0006] The steel casing is used for mud wall protection, hole collapse prevention and positioning during pile foundation drilling. When the lower casing BC of a bored pile is positioned by the positioning frame, if there is a deviation greater than the specified deviation at the top B of the lower casing due to various reasons, the horizontal force used to adjust the deviation to return to the precise position is , the BC section of the lower casing is subjected to horizontal force The top of the elastic foundation beam is free, ignoring the gravity effect of the steel casing and the vibrating hammer. According to the theory of elastic mechanics, the differential equation of its bending under force and the displacement of the top of the lower casing B are for:

[0007] Formula 1:

[0008]

[0009] After the top B of the lower casing returns to the precise position, the top A of the upper casing is fixed by a vibrating hammer, the bottom end of the upper casing is inserted into the socket joint, and the vibrating hammer presses the upper casing. At this time, the top A of the upper casing is elastically embedded with the vibrating hammer. The horizontal force used to adjust the deviation of the top B of the lower casing is According to the law of action and reaction, the top of the socket joint has a reverse action. force, which is equal to , elastic rebound is , reverse The force is borne by the upper casing and the lower casing together.

[0010] Formula 2:

[0011]

[0012]

[0013]

[0014]

[0015] Formula 3:

[0016]

[0017] The symbols in Formula 1, Formula 2 and Formula 3 are defined as:

[0018] ——The length from the surface of the solidified soil of the soft soil foundation to the top of the socket joint, ;

[0019] ——Thickness of the surface solidified soil of soft soil foundation, ;

[0020] ——The length from the surface of the solidified soil of the soft soil foundation to the bottom of the lower casing, ;

[0021] ——The length from the top of the socket joint to the bottom of the vibrating hammer, ;

[0022] - calculated width of steel casing, ;

[0023] ——The center of the steel casing on the surface of the surface solidified soil The point is the horizontal coordinate value of the origin, ;

[0024] y1(z), y2(z), y3(z) and y4(z) are the center points of the steel casing on the surface of the surface solidified soil. The stress-deformation curve equations of the steel casing BC, BA, BO and OC sections with point as the origin are: ;

[0025] ——The proportional coefficient of the resistance coefficient of the surface solidified soil and the lower soft soil is determined through experiments. In the absence of test data, it is determined according to relevant specifications. ;

[0026] ——The proportional coefficient of the resistance coefficient of the surface solidified soil is determined through experiments. In the absence of test data, it is determined according to relevant specifications. ;

[0027] ——The proportional coefficient of the resistance coefficient of the lower soft soil is determined through experiments. In the absence of test data, it is determined according to relevant specifications. ;

[0028] ——Conversion coefficient of the proportional coefficient of the resistance coefficient of the surface solidified soil and the underlying soft soil;

[0029] ——respectively the bending stiffness of the lower casing and the upper casing, ;

[0030] ——B is generated at the top of the lower casing When displacement is made, adjust the displacement greater than the allowable deviation The horizontal force required to return to the exact position is , ;

[0031] ——After the top B of the lower casing returns to the precise position, the top A of the upper casing is fixed by a vibrating hammer, and the bottom of the upper casing is inserted into the socket joint. The vibrating hammer presses the upper casing. At this time, the top A of the upper casing is elastically embedded with the vibrating hammer. The horizontal force used to adjust the deviation of the top B of the lower casing is According to the law of action and reaction, the top of the socket joint has a reverse action. force, whose value is equal to , ;

[0032] --exist Under the action of force, the horizontal reaction force of the elastic embedment of the top of the upper casing A is ;

[0033] --exist Under the action of the upper casing, the horizontal force shared by the upper casing at the bottom end is ;

[0034] --exist Under the action of force, the horizontal force shared by the lower casing at the top B of the lower casing is: ;

[0035] ——The upper casing BA section is Under the action of force, the bending moment reaction force of the elastic embedment of the top of the upper casing A is ;

[0036] ——For the calculation parameters of steel casing as elastic foundation beam, please refer to "JTG3363-2019 Highway Bridge and Culvert Foundation and Foundation Design Code";

[0037] ——After the lower casing is positioned by the positioning frame and driven into the soft soil foundation, due to various reasons, there is a deviation greater than the specified value at the top B of the lower casing. ;

[0038] ——After the top B of the lower casing returns to the precise position, the vibrating hammer elastically embeds the top A of the upper casing, and the bottom of the upper casing is inserted into the socket joint. The force used to adjust the elastic deviation of the top B of the lower casing is The reaction force Produce elastic rebound, ;

[0039] ——The upper casing BA section is The horizontal displacement under the action of force, ;

[0040] ——elastic embedding horizontal resistance coefficient of the top A of the upper casing BA section, ;

[0041] - allowable error of steel casing, .

[0042] A limiting ring is provided at the bottom of the upper casing, which is a plurality of continuously connected annular steel plates welded at 900mm to 1100mm vertically around the outer wall of the bottom of the upper casing. The thickness of each annular steel plate is 16mm to 18mm and the height is 90mm to 110mm. Each annular steel plate is welded to the outer wall of the upper casing by groove welding.

[0043] The length of the socket joint is 800mm to 1000mm, which is used to control the length of the socket joint and drive the lower casing to be driven into the soft soil foundation along with the upper casing by the vibrating hammer; the vibrating hammer is the power component of the pile driver, and the power of the vibrating hammer is selected according to the size of the steel casing and the characteristics of the soft soil foundation.

[0044] The Bailey sheet row group is composed of a plurality of Bailey sheet rows arranged in parallel in the transverse direction, and each Bailey sheet row is formed by two Bailey sheets connected to each other.

[0045] The upper crossbeam is fixed by double I-beams, the lower crossbeam is a single I-beam, and the cross brace is fixed by two cross-shaped I-beams.

[0046] The positioning frame is provided with a plurality of steel chisels, and the plurality of steel chisels fix the positioning frame on the soft soil foundation.

[0047] The two upper cross beams on the outside are fixedly connected to the tops of the two spanning groups of Bailey sheets via fixing bolts, the two upper cross beams on the inside are movably connected to the tops of the two spanning groups of Bailey sheets via adjusting bolts, and the two lower cross beams are fixedly connected to the bottoms of the two spanning groups of Bailey sheets via fixing bolts.

[0048] The steel casing is a steel pipe, the outer diameter of the upper casing is 1.0mm-1.2mm smaller than the inner diameter of the lower casing, the ovality is ≤3mm, and the length of the lower end of the upper casing inserted into the top end of the lower casing is the length of the socket joint.

[0049] An operating method for an adjustable assembled guide positioning frame for burying a steel casing comprises the following steps:

[0050] Step 1: Make a positioning frame

[0051] ① Design and manufacture the components of the positioning frame according to the size of the steel casing;

[0052] ② Assemble the positioning frame, and the quality meets the design requirements;

[0053] Step 2: Solidify the soft soil on the surface

[0054] ①Select qualified curing agent and determine the mix ratio of solidified soft soil through experiments;

[0055] ② According to the plane layout range of the pile foundation, use an excavator to mix the surface soft soil evenly, add curing agent, and maintain it to the designed strength;

[0056] Step 3: Install the fixed positioning frame

[0057] ①Measure and lay out to determine the position of each steel chisel on the positioning frame;

[0058] ② After lifting the positioning frame and placing it at the specified position, use multiple steel pins to fix the positioning frame accurately:

[0059] Step 4: Construction of lower casing

[0060] ① The pile driver is in place, the lower casing is hoisted, and the vibrating hammer of the pile driver clamps the top of the lower casing. The center of the vibrating hammer is in a straight line with the center of the lower casing and the positioning frame;

[0061] ② The lower casing is lowered into the positioning frame, and the two lower beams at the bottom of the positioning frame are used to clamp and fix it, and the two inner upper beams at the top of the positioning frame are used to adjust and clamp it, so as to accurately locate and fix the construction position of the lower casing, and verify that the coordinates of the lower casing meet the design requirements;

[0062] ③ Continue to lower the casing to insert it into the surface solidified soil, start the vibrating hammer to hammer the top of the casing to 30cm to 50cm above the positioning frame and then stop;

[0063] ④Pull out the steel chisel of the positioning frame, dismantle the positioning frame and lift it to the position of the next pile foundation, and fix the positioning frame accurately according to step 3;

[0064] ⑤ Start the vibrating hammer again and hammer the top of the casing to a height h0 above the surface of the surface solidified soil;

[0065] ⑥Measure whether the top deviation of the lower casing meets the design requirements in order to determine the next measures;

[0066] Step 5: Construction of upper casing

[0067] (1) When the top deviation of the lower casing meets the design requirements

[0068] ① The pile driver is in place, the upper casing is lifted, the vibrating hammer of the pile driver clamps the top of the upper casing, the bottom of the upper casing is aligned with the top of the lower casing and lowered until the lower edge of the limit ring is close to the top of the lower casing;

[0069] ② Start the vibratory hammer to drive the upper casing into the designed depth;

[0070] (2) When the error of the top of the lower casing does not meet the design requirements

[0071] If the completed lower casing is the first lower casing of the bridge pier, it will be temporarily left until the second lower casing is completed. According to step 3 and step 4, the deviation of the second lower casing adjacent to the deviation direction of the first lower casing can be adjusted by hand chain hoist, or the deviation of the first lower casing under construction can be adjusted by winch using the completed pile foundation and bridge pier.

[0072] ① Use formula 1 to calculate the amount of time required to adjust the top of the first lower casing to restore the deviation. Force, initially select the force-applying tool; use formula 2 to verify the elastic rebound Meet design requirements; such as elastic rebound If the design requirements are not met, the force until until;

[0073] ② Tie the top of the first lower casing and the top of the second lower casing with steel wire rope;

[0074] ③ Use a hand chain hoist to connect two steel wire ropes between the top of the first lower casing and the top of the second lower casing. Install a dynamometer on the hand chain hoist and record the reading of the dynamometer. The hand chain hoist restores the deviation of the first lower casing to the correct position; if the pulling force of the hand chain hoist is too small to restore the lower casing to the correct position, use a winch to apply force to achieve the desired purpose. A dynamometer is also installed on the winch and the reading of the dynamometer is recorded;

[0075] ④ The pile driver is positioned at the first pile position where the deviation does not meet the requirements, the upper casing is hoisted, the vibrating hammer of the pile driver clamps the top of the upper casing, the bottom of the upper casing is aligned with the top of the lower casing and lowered until the lower edge of the limit ring is close to the top of the lower casing;

[0076] ⑤ Release all the hand chain hoists or winches to drive the upper casing into the designed depth;

[0077] ⑥Measure the deviation of the top of the first upper casing, which must meet the design requirements;

[0078] Before actual construction, the lower and upper casings should be tested to obtain verification results of theoretical and actual values ​​and construction experience before formal construction to ensure the quality of the project;

[0079] Step 6: Pour concrete and pull up the casing

[0080] ①Select a circulation drilling rig suitable for on-site drilling and bring it into place;

[0081] ② Mud preparation: sufficient quantity and qualified performance of clay or bentonite drilling wall mud to ensure appropriate mud head in the steel casing;

[0082] ③ When the drilling depth reaches the design requirements, check the hole depth, hole diameter, hole position and hole shape;

[0083] ④ The hole is cleaned by grouting method and the steel cage is lowered;

[0084] ⑤Underwater concrete pouring completed 1 h After that, when the concrete has reached the initial setting time but has not reached the final setting time, the vibrating hammer is turned on and the casing is slowly lifted by a crane.

[0085] Compared with the prior art, the present invention provides an adjustable assembled guide and positioning frame for burying steel casing, whose structure is composed of two groups of Bailey sheet groups, two outer upper cross beams spanning the tops of the two groups of Bailey sheet groups and fixedly connected, two inner upper cross beams spanning the tops of the two groups of Bailey sheet groups and movably connected, two lower cross beams spanning the bottoms of the two groups of Bailey sheet groups and movably connected, and cross braces respectively connecting the two groups of Bailey sheet groups. The positioning frame has the following advantages: first, the adjustable assembled guide and positioning frame is set for positioning, which can reduce the burying deviation of the steel casing, and part of the steel casing can be reused, which not only improves the construction quality of bored piles, but also saves resources; second, the deviation of the steel casing during construction is adjusted by utilizing the existing constructed steel casing, pile foundation, and bridge piers, which is scientific and reasonable; third, the provided calculation method has clear principles, is practical and easy to implement, can be used as a guide for the construction of steel casing, and improves safety and quality performance. Therefore, the positioning frame of the present invention has the advantages of simple structure, convenient construction, adjustable positioning accuracy, low cost, safety and reliability, and reusable resources. Combined with the corresponding operation method, it can bring higher economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0086] Figure 1 It is a schematic diagram of the structural elevation of the present invention.

[0087] Figure 2 for Figure 1 Left view of .

[0088] Figure 3 for Figure 1 Top view of the .

[0089] Figure 4 for Figure 1 Magnified view of a socket joint.

[0090] Figure 5 It is the force calculation diagram for the free top of the lower casing adjustment deviation.

[0091] Figure 6 This is the force calculation diagram for the elastically embedded upper casing of the vibratory hammer. DETAILED DESCRIPTION

[0092] The embodiments of the present invention will be described in detail below with reference to the above-mentioned drawings.

[0093] like Figure 1 to Figure 6 As shown, 1. soft soil foundation, 11. lower soft soil, 12. surface solidified soil, 2. positioning frame, 21. Bailey plate group, 211. Bailey plate row, 212. Bailey plate, 22. upper beam, 23. lower beam, 24. fixing bolt, 25. adjusting bolt, 26. cross brace, 3. steel chisel, 4. steel casing, 41. lower casing, 42. upper casing, 43. socket joint, 44. limiting ring, 5. vibrating hammer.

[0094] An adjustable assembled guide positioning frame for burying steel casing and an operation method thereof, such as Figure 1~Figure 4 As shown, it relates to the field of bridge foundation construction. It is mainly installed on a soft soil foundation 1 and is used to accurately position and fix the lower casing 41 of the steel casing 4. The lower casing is then constructed on the soft soil foundation 1 through the vibrating hammer 5 of the pile driver. The bottom end of the upper casing 42 of the steel casing 4 is connected to the top end of the lower casing 41 through a socket joint 43.

[0095] The soft soil foundation 1 is divided into two layers. The lower soft soil 11 generally refers to clay soil in a soft plastic to fluid plastic state with high natural water content, high compressibility, low bearing capacity and very low shear strength. Bored pile foundations need to be set up for bridge construction on soft soil foundations; the upper solidified soil, that is, the surface solidified soil 12 is the soft soil surface layer solidified to a certain depth using a curing agent, as a construction access road for the construction of bored pile foundations.

[0096] The positioning frame 2 includes two groups of Bailey sheet arrays 21 arranged in parallel in the transverse direction, four upper beams 22 arranged parallel to each other and across the top of the two groups of Bailey sheet arrays 21 in the longitudinal direction, and two lower beams 23 arranged parallel to each other and across the bottom of the two groups of Bailey sheet arrays 21 in the longitudinal direction.

[0097] Among them, horizontal Figure 3 The inner arrow marks the north-south direction, and the vertical direction is Figure 3 In the east-west direction marked by the inner arrow, the width of the outer wall of the casing 41 needs to be reserved in the middle of the two groups of Bailey sheet rows 21, that is, in the middle of the horizontal direction. Figure 3 As shown, two groups of Bailey sheet arrays 21 are respectively arranged on both sides of the steel casing 4.

[0098] The Bailey sheet row group 21 is composed of several rows of Bailey sheet rows 211 arranged in parallel in the transverse direction. In this embodiment, each group of Bailey sheet rows 21 is composed of three rows of Bailey sheet rows 211 arranged in parallel and equidistantly. Each row of Bailey sheet rows is composed of two finished Bailey sheets 212 connected to each other by multiple fixing bolts 24. The Bailey sheet 212 is a standard steel truss structure, which can be combined and spliced ​​into structures such as gantry cranes, guide beams, bridge erection machines, temporary or permanent bridges, construction platforms, etc. It can be reused and has a wide range of applications.

[0099] The upper crossbeam 22 is made of double-piece I-beams welded or fixed with bolts. The two outer upper crossbeams are fixedly connected to the tops of the two spanning groups of Bailey sheet arrays 21 by multiple fixing bolts 24, and the two inner upper crossbeams 22 are movably connected to the tops of the two spanning groups of Bailey sheet arrays 21 by multiple adjusting bolts 25. The inner width between the two inner upper crossbeams 22 also serves as the outer wall diameter of the lower casing 41, which can be used to adjust and clamp the top of the lower casing, and the position of the lower casing 41 can be synchronously adjusted by adjusting the longitudinal position distance of the two inner upper crossbeams 22, that is, the construction position of the lower casing 41 can be accurately positioned.

[0100] The lower cross beam 23 is a single I-beam, and the two lower cross beams 23 are fixedly connected to the bottoms of the two spanning Bailey sheet arrays 21 by a plurality of fixing bolts 24 .

[0101] In this way, the lower casing 41 is constructed on the soft soil foundation 1 by sequentially passing through the two inner movable upper beams 22 and the two fixed lower beams 23, and the two lower beams 23 can clamp and fix the lower casing 41, and the two inner upper beams 22 can adjust and clamp the lower casing 41.

[0102] The cross brace 26 is formed by welding or bolting two crossed I-beams, and the four end points of the cross are respectively welded and fixed between the top and bottom ends of the two groups of Bailey sheet arrays 21 along the longitudinal direction, thereby forming a stable structure of the positioning frame.

[0103] The steel casing 4 is a steel pipe, which can be divided into two sections: a lower casing 41 and an upper casing 42. The outer diameter of the upper casing is 1.0mm to 1.2mm smaller than the inner diameter of the lower casing, and the ovality is ≤3mm. The length of the bottom end of the upper casing 42 inserted into the top end of the lower casing 41 is the length of the socket joint 43.

[0104] At the same time, a limiting ring 44 is provided at the bottom of the upper casing 42. The limiting ring is a plurality of continuously connected annular steel plates welded at 900mm to 1100mm vertically around the outer wall of the bottom of the upper casing 42. The thickness of each annular steel plate is 16mm to 18mm and the height is 90mm to 110mm. Each annular steel plate is welded to the outer wall of the upper casing by groove welding.

[0105] The length of the socket joint 43 is 800mm~1000mm, and it is mainly used to control the length of the socket joint and drive the lower casing 41 and the upper casing 42 to be driven into the soft soil foundation 1 by the vibrating hammer 5; the vibrating hammer 5 is the power component of the pile driver, and the power of the vibrating hammer is selected according to the size of the steel casing 4 and the characteristics of the soft soil foundation 1.

[0106] The positioning frame 2 is provided with a plurality of steel chisels 3, which are steel rods with a blade at one end. When the positioning frame 2 is placed on the soft soil foundation 1, the positioning frame 2 can be fixed on the soft soil foundation 1 by the plurality of steel chisels 3 under the condition of precise longitudinal positioning.

[0107] The bored piles are bridge pile foundations, and each pier can be provided with multiple piles; the steel casing 4 is used for mud wall protection, hole collapse prevention and positioning when the pile foundation is drilled. BC After positioning by the positioning frame, due to various reasons, at the top of the lower casing 41 B When there is a deviation greater than the specified value, the horizontal force used to adjust the deviation to the precise position using a jack, hand chain hoist or winch is , lower casing BC Segment is subject to horizontal force The elastic foundation beam with free top, ignoring the gravity effect of steel casing 4 and vibrating hammer 5, according to the theory of elastic mechanics, the differential equation of its bending under force and the displacement of the top B of the lower casing are for:

[0108] Formula 1:

[0109]

[0110] After the top B of the lower casing 41 returns to the precise position, the vibrating hammer 5 fixes the top A of the upper casing 42, and the bottom end of the upper casing 42 is inserted into the socket joint 43. The vibrating hammer 5 presses the upper casing 42. At this time, the top A of the upper casing 42 is elastically embedded with the vibrating hammer 5. Since the horizontal force used to adjust the deviation of the top B of the lower casing 41 is According to the law of action and reaction, the top B of the socket joint 43 has a reverse action. force, which is equal to , elastic rebound is , reverse The force is borne by the upper casing 42 and the lower casing 41.

[0111] Formula 2:

[0112]

[0113]

[0114]

[0115]

[0116] Formula 3:

[0117]

[0118] The symbols in Formula 1, Formula 2 and Formula 3 are defined as:

[0119] ——The length from the surface of the solidified soil 12 of the soft soil foundation 1 to the top of the socket joint 43, ;

[0120] ——Thickness of the surface solidified soil 12 of the soft soil foundation 1, ;

[0121] ——The length from the surface of the solidified soil 12 of the soft soil foundation 1 to the bottom of the lower casing 41, ;

[0122] ——The length from the top of the socket joint 43 to the bottom of the vibrating hammer 5, ;

[0123] - calculated width of steel casing 4, ;

[0124] ——Use surface solidified soil 12 surface steel casing 4 center The point is the horizontal coordinate value of the origin, ;

[0125] y1(z), y2(z), y3(z) and y4(z) are the center points of the steel casing on the surface of the surface solidified soil 12. The stress-deformation curve equations of the steel casing BC, BA, BO and OC sections with point as the origin are: ;

[0126] ——The proportional coefficient of the conversion resistance coefficient of the surface solidified soil 12 and the lower soft soil 11 is determined through experiments. In the absence of test data, it is determined according to relevant specifications. ;

[0127] ——The proportional coefficient of the resistance coefficient of the surface solidified soil 12 is determined through experiments. In the absence of test data, it is determined according to relevant specifications. ;

[0128] ——The proportional coefficient of the resistance coefficient of the lower soft soil 11 is determined through experiments. In the absence of test data, it is determined according to relevant specifications. ;

[0129] - conversion factor of the proportional coefficient of the resistance coefficient of the surface solidified soil 12 and the underlying soft soil 11;

[0130] ——are the bending stiffness of the lower casing 41 and the upper casing 42, respectively, ;

[0131] ——B is generated at the top of the lower casing When displacement is made, adjust the displacement greater than the allowable deviation The horizontal force required to return to the exact position is , ;

[0132] ——After the top B of the lower casing 41 returns to the precise position, the vibrating hammer 5 fixes the top A of the upper casing 42, and the bottom end of the upper casing 42 is inserted into the socket joint 43. The vibrating hammer 5 presses the upper casing 42. At this time, the top A of the upper casing 42 is elastically embedded with the vibrating hammer 5. Since the horizontal force used to adjust the deviation of the top B of the lower casing 41 is According to the law of action and reaction, the top B of the socket joint 43 has a reverse action. force, whose value is equal to , ;

[0133] --exist Under the action of force, the horizontal reaction force of the elastic embedment of the top of the upper casing A is ;

[0134] --exist Under the action of the upper casing, the horizontal force shared by the upper casing at the bottom end is ;

[0135] --exist Under the action of force, the horizontal force shared by the lower casing at the top B of the lower casing is: ;

[0136] ——The upper casing BA section is Under the action of force, the bending moment reaction force of the elastic embedment of the top of the upper casing A is ;

[0137] ——For the calculation parameters of steel casing as elastic foundation beam, please refer to "JTG3363-2019 Highway Bridge and Culvert Foundation and Foundation Design Code";

[0138] ——After the lower casing 41 is positioned and driven into the soft soil foundation 1 by the positioning frame 2, due to various reasons, there is a deviation greater than the specified value at the top B of the lower casing. ;

[0139] ——After the top B of the lower casing returns to the precise position, the vibrating hammer 5 is elastically embedded in the top A of the upper casing 42, and the bottom end of the upper casing 42 is inserted into the socket joint 43. The force used to adjust the elastic deviation of the top B of the lower casing is The reaction force Produce elastic rebound, ;

[0140] ——The upper casing BA section is The horizontal displacement under the action of force, ;

[0141] ——elastic embedding horizontal resistance coefficient of the top A of the upper casing BA section, ;

[0142] - allowable error of steel casing 4, .

[0143] The operating method of the present invention comprises the following steps:

[0144] Step 1: Make a positioning frame

[0145] ① Design and manufacture the components of the positioning frame 2 according to the size of the steel casing 4;

[0146] ② Assemble the positioning frame 2, and the quality meets the design requirements;

[0147] Step 2: Solidify the soft soil on the surface

[0148] ①Select qualified curing agent and determine the mix ratio of solidified soft soil through experiments;

[0149] ② According to the plane layout range of the pile foundation, use an excavator to mix the surface soft soil evenly, add curing agent, and maintain it to the designed strength;

[0150] Step 3: Install the fixed positioning frame

[0151] ① Measure and determine the position of each steel chisel 3 on the positioning frame 2;

[0152] ② After lifting the positioning frame 2 and placing it at the specified position, use multiple steel chisels 3 to accurately fix the positioning frame:

[0153] Step 4: Construction of lower casing

[0154] ① The pile driver is in place, the lower casing 41 is lifted, and the vibrating hammer 5 of the pile driver clamps the top of the lower casing, and the center of the vibrating hammer 5 is in a straight line with the center of the lower casing 41 and the positioning frame 2;

[0155] ② The lower casing 41 is lowered into the positioning frame 2, and the construction position of the lower casing 41 is accurately positioned and fixed by clamping the two lower crossbeams 23 at the bottom of the positioning frame 2 and adjusting the clamping by the two inner upper crossbeams 22 at the top of the positioning frame, and the coordinates of the lower casing are checked to meet the design requirements;

[0156] ③ Continue to lower the casing 41 to insert it into the surface solidified soil 12, start the vibrating hammer 5 to hammer the top of the casing 41 to 30cm to 50cm above the positioning frame 2 and then stop;

[0157] ④ Pull out the steel drill 3 on the positioning frame 2, dismantle the positioning frame and lift it to the position of the next pile foundation, and fix the positioning frame accurately according to step 3;

[0158] ⑤ Start the vibrating hammer 5 again and hammer the top of the casing 41 to a height h0 above the surface of the surface solidified soil 12;

[0159] ⑥Measure whether the top deviation of the lower casing 41 meets the design requirements in order to determine the next measures;

[0160] Step 5: Construction of upper casing

[0161] (1) When the top deviation of the lower casing meets the design requirements

[0162] ① The pile driver is in place, the upper casing 42 is lifted, the vibrating hammer 5 of the pile driver clamps the top of the upper casing, the bottom end of the upper casing 42 is aligned with the top of the lower casing 41 and lowered until the lower edge of the limit ring 44 is close to the top of the lower casing;

[0163] ② Start the vibrating hammer 5 to drive the upper casing 42 into the designed depth;

[0164] (2) When the error of the top of the lower casing does not meet the design requirements

[0165] If the completed lower casing 41 is the first lower casing of the bridge pier, it is temporarily left to be processed after the second lower casing is completed. According to step 3 and step 4, the deviation of the second lower casing adjacent to the first lower casing in the deviation direction is adjusted by hand chain hoist, or the deviation of the first lower casing under construction using the completed pile foundation and bridge pier is adjusted by winch.

[0166] ① Use formula 1 to calculate the amount of time required to adjust the top of the first lower casing to restore the deviation. Force, initially select the force-applying tool; use formula 2 to verify the elastic rebound Meet design requirements; such as elastic rebound If the design requirements are not met, the force until until;

[0167] ② Tie the top of the first lower casing and the top of the second lower casing with steel wire rope;

[0168] ③ Use a hand chain hoist to connect two steel wire ropes between the top of the first lower casing and the top of the second lower casing. Install a dynamometer on the hand chain hoist and record the reading of the dynamometer. The hand chain hoist restores the deviation of the first lower casing to the correct position; if the pulling force of the hand chain hoist is too small to restore the lower casing to the correct position, use a winch to apply force to achieve the desired purpose. A dynamometer is also installed on the winch and the reading of the dynamometer is recorded;

[0169] ④ The pile driver is positioned at the first pile position where the deviation does not meet the requirements, the upper casing is hoisted, the vibrating hammer of the pile driver clamps the top of the upper casing, the bottom of the upper casing is aligned with the top of the lower casing and lowered until the lower edge of the limit ring is close to the top of the lower casing;

[0170] ⑤ Release all the hand chain hoists or winches to drive the upper casing into the designed depth;

[0171] ⑥Measure the deviation of the top of the first upper casing, which must meet the design requirements;

[0172] Before actual construction, the lower casing 41 and the upper casing 42 should be tested, and the verification results of the theoretical value and the actual value and the construction experience should be obtained before the formal construction is carried out to ensure the quality of the project;

[0173] Step 6: Pour concrete and pull up the casing

[0174] ①Select a circulation drilling rig suitable for on-site drilling and bring it into place;

[0175] ② Mud preparation: sufficient quantity and qualified performance of clay or bentonite drilling wall mud to ensure appropriate mud head in the steel casing;

[0176] ③ When the drilling depth reaches the design requirements, check the hole depth, hole diameter, hole position and hole shape;

[0177] ④ The hole is cleaned by grouting method and the steel cage is lowered;

[0178] ⑤ One hour after the underwater concrete pouring is completed, when the concrete has reached the initial setting time but has not reached the final setting time, start the vibrating hammer and slowly lift the casing with a crane.

[0179] The above description is only a specific embodiment of the present invention. Those skilled in the art should understand that any structural design similar to this embodiment should be included in the protection scope of the present invention.

Claims

1. An adjustable assembled guide positioning frame for burying a steel casing, used for accurately positioning and fixing a lower casing (41) of a steel casing (4) on a soft soil foundation (1) by means of a vibrating hammer (5), wherein the bottom end of an upper casing (42) of the steel casing (4) is connected to the top end of the lower casing (41) via a socket joint (43); the soft soil foundation (1) comprises a lower layer of soft soil (11) and a surface layer of solidified soil (12), Features: The positioning frame (2) comprises two sets of parallel Bailey sheet arrays (21) arranged in the transverse direction, four upper crossbeams (22) arranged in parallel with each other and arranged in the longitudinal direction across the tops of the two sets of Bailey sheet arrays (21), two lower crossbeams (23) arranged in parallel with each other and arranged in the longitudinal direction across the bottoms of the two sets of Bailey sheet arrays (21), and a cross brace (26) connected to each other between the two sets of Bailey sheet arrays (21); the two outer upper crossbeams (22) are fixedly connected to the tops of the two spanning Bailey sheet arrays (21), the two inner upper crossbeams (22) are movably connected to the tops of the two spanning Bailey sheet arrays (21), and the two lower crossbeams (23) are fixedly connected to the bottoms of the two spanning Bailey sheet arrays (21). The two groups of Bailey sheet arrays (21) are respectively arranged on both sides of the steel casing (4); the lower casing (41) is constructed on the soft soil foundation (1) by sequentially passing through two inner movable upper crossbeams (22) and two fixed lower crossbeams (23), and the two lower crossbeams (23) clamp and fix the lower casing (41), and the two inner upper crossbeams (22) adjust and clamp the lower casing (41); the steel casing (4) is used for mud wall protection, hole collapse prevention and positioning during pile foundation drilling. When the lower casing of a bored pile is positioned by the positioning frame (2), if there is a displacement greater than the allowable deviation at the top B of the lower casing due to various reasons, the horizontal force used to adjust the deviation to return to the precise position is , the BC section of the lower casing is subjected to horizontal force The top of the elastic foundation beam is free, and the gravity effect of the steel casing (4) and the vibrating hammer (5) is ignored. According to the theory of elastic mechanics, the differential equation of the bending force of the BC section of the lower casing and the displacement of the top B of the lower casing are for: Formula 1: After the top B of the lower casing returns to the precise position, the vibrating hammer (5) fixes the top A of the upper casing, the bottom end of the upper casing (42) is inserted into the socket joint (43), and the vibrating hammer (5) presses the upper casing (42). At this time, the top A of the upper casing is elastically embedded with the vibrating hammer (5). The horizontal force used to adjust the displacement of the top B of the lower casing greater than the allowable deviation is According to the law of action and reaction, there is a reverse force at the top of the socket joint. , The value is equal to , the elastic rebound at the top of the socket joint is , the reverse force The upper casing (42) and the lower casing (41) share the same responsibility. Formula 2: Formula 3: The symbols in Formula 1, Formula 2 and Formula 3 are defined as: ——The length from the surface of the solidified soil (12) of the soft soil foundation (1) to the top of the socket joint, ; ——Thickness of the surface solidified soil (12) of the soft soil foundation (1), ; ——The length from the surface of the solidified soil (12) of the soft soil foundation (1) to the bottom of the lower casing (41), ; - the length from the top of the socket joint to the bottom of the vibrating hammer (5), ; - calculated width of the steel casing (4), ; ——The center of the steel casing (4) on the surface of the surface solidified soil (12) The point is the vertical coordinate value of the origin, ; y 1 (z), y 2 (z), y 3 (z) and y 4 (z)——the center of the steel casing (4) on the surface of the surface solidified soil (12) The stress-deformation curve equations of the steel casing BC, BA, BO and OC sections with point as the origin are: ; ——The proportional coefficient of the resistance coefficient between the surface solidified soil (12) and the lower soft soil (11) shall be determined through tests. In the absence of test data, it shall be determined according to relevant specifications. ; ——The proportional coefficient of the resistance coefficient of the surface solidified soil (12) is determined through experiments. In the absence of test data, it is determined according to relevant specifications. ; ——The proportional coefficient of the resistance coefficient of the lower soft soil (11) is determined through experiments. In the absence of test data, it is determined according to relevant specifications. ; ——conversion factor of the proportionality coefficient between the resistance coefficients of the surface solidified soil (12) and the underlying soft soil (11); ——are the bending stiffness of the lower casing (41) and the upper casing (42), ; ——B is generated at the top of the lower casing When displacement is made, adjust the displacement greater than the allowable deviation The horizontal force required to return to the exact position is , ; ——After the top B of the lower casing returns to the precise position, the vibrating hammer (5) fixes the top A of the upper casing, the bottom end of the upper casing (42) is inserted into the socket joint (43), and the vibrating hammer (5) presses the upper casing (42). At this time, the top A of the upper casing is elastically embedded with the vibrating hammer (5). The horizontal force used to adjust the displacement of the top B of the lower casing greater than the allowable deviation is According to the law of action and reaction, when the upper casing and the lower casing are subjected to force together, there is a reverse force at the top of the socket joint. The force sharing value at the top B of the lower casing is But in the opposite direction, ; --exist Under the action of the elastic embedding horizontal reaction force of the top A of the upper casing, ; --exist Under the action of the upper casing (42), the horizontal force shared by the upper casing at the bottom end of the upper casing is ; --exist Under the action of the force, the horizontal force shared by the lower casing (41) at the top B of the lower casing is: ; ——The upper casing BA section is Under the action of force, the bending moment reaction force of the elastic embedment of the top of the upper casing A is ; ——For the calculation parameters of steel casing as elastic foundation beam, please refer to "JTG3363-2019 Highway Bridge and Culvert Foundation and Foundation Design Code"; ——After the lower casing (41) is positioned by the positioning frame (2) and driven into the soft soil foundation (1), displacement occurs at the top B of the lower casing due to various reasons. ; ——After the top B of the lower casing returns to the precise position, the vibrating hammer (5) elastically embeds the top A of the upper casing, and the bottom end of the upper casing (42) is inserted into the socket joint (43). The force used to adjust the elastic deviation of the top B of the lower casing is The reaction force The elastic rebound of the top B of the lower casing is generated. ; ——The upper casing BA section is The horizontal displacement of end B under the action of force, ; ——Elastic embedding horizontal resistance coefficient of the top of the upper casing A, ; - the permissible error of the steel casing (4), ; A limiting ring (44) is provided at the bottom of the upper casing (42), and the limiting ring is a plurality of continuously connected annular steel plates vertically welded around the outer wall of the bottom of the upper casing (42), each annular steel plate has a thickness of 16 mm to 18 mm and a height of 90 mm to 110 mm, and each annular steel plate is welded to the outer wall of the upper casing (42) by groove welding; a plurality of steel chisels (3) are provided on the positioning frame (2), and the plurality of steel chisels fix the positioning frame (2) on the soft soil foundation (1).

2. The adjustable assembled guide and positioning frame for burying steel casing according to claim 1, Features: The length of the socket joint (43) is 800 mm to 1000 mm; the vibrating hammer (5) is a power component of the pile driver, and the power of the vibrating hammer (5) is selected according to the size of the steel casing (4) and the characteristics of the soft soil foundation (1).

3. The adjustable assembled guide and positioning frame for burying steel casing according to claim 1, Features: The Bailey sheet row group (21) is composed of a plurality of parallel rows of Bailey sheet rows (211) arranged in a transverse direction, and each row of Bailey sheet rows (211) is composed of two Bailey sheets (212) connected to each other.

4. The adjustable assembled guide and positioning frame for burying steel casing according to claim 1, Features: The upper crossbeam (22) is a double-jointed I-beam, the lower crossbeam (23) is a single I-beam, and the cross brace (26) is formed by fixing two cross-intersecting I-beams.

5. The adjustable assembled guide and positioning frame for burying steel casing according to claim 1, Features: The two upper cross beams (22) on the outside are fixedly connected to the tops of the two spanning Bailey sheet arrays (21) via fixing bolts (24), the two upper cross beams (22) on the inside are movably connected to the tops of the two spanning Bailey sheet arrays (21) via adjusting bolts (25), and the two lower cross beams (23) are fixedly connected to the bottoms of the two spanning Bailey sheet arrays (21) via fixing bolts (24).

6. The adjustable assembled guide and positioning frame for burying steel casing according to claim 1, Features: The outer diameter of the upper casing (42) of the steel casing is 1.0 mm to 1.2 mm smaller than the inner diameter of the lower casing (41). The length of the lower casing (41) inserted into the top of the lower casing (41) is the length of the spigot-and-socket joint (43).

7. A method for operating the adjustable assembled guide and positioning frame for burying a steel casing according to claim 1, Features The operation method includes the following steps: Step 1: Make a positioning frame ① Design and manufacture the components of the positioning frame (2) according to the size of the steel casing (4); ② Assemble the positioning frame (2); Step 2: Solidify the soft soil on the surface ①Select qualified curing agent and test to determine the mix ratio of curing surface soft soil; ② According to the plane layout range of the pile foundation, use an excavator to mix the surface soft soil evenly, add curing agent, and maintain it to the designed strength; Step 3: Install the fixed positioning frame ① measuring and setting out to determine the position of each steel bar (3) on the positioning frame (2); ② After lifting the positioning frame (2) and placing it at the specified position, fix the positioning frame (2) using a plurality of steel chisels (3): Step 4: Construction of lower casing ① The pile driver is in place, the lower casing is lifted, and the vibrating hammer (5) of the pile driver clamps the top of the lower casing (41), so that the center of the vibrating hammer (5) is in a straight line with the center of the lower casing (41) and the positioning frame (2); ② The lower casing (41) is lowered into the positioning frame (2), and the lower casing is clamped and fixed by two lower cross beams (23) at the bottom of the positioning frame and adjusted and clamped by two inner upper cross beams (22) at the top of the positioning frame to accurately locate the construction position of the lower casing (41); ③ Continue to lower the casing (41) so that the lower casing is inserted into the surface solidified soil (12), start the vibrating hammer (5) to hammer the top of the lower casing (41) until it is 30 cm to 50 cm above the positioning frame (2) and then stop; ④ Pull out the steel chisel (3) on the positioning frame (2), remove the positioning frame and lift it to the position of the next pile foundation, and fix the positioning frame (2) according to step 3; ⑤ Start the vibrating hammer (5) again and hammer the top of the lower casing (41) to a height h above the surface of the surface solidified soil (12). 0 ; ⑥ Measure the displacement of the top of the lower casing (41) to see whether it meets the design requirements, so as to determine the next step; Step 5: Construction of upper casing (1) When , the displacement of the top of the lower casing meets the design requirements. ① The pile driver is in place, the upper casing (42) is hoisted, the vibrating hammer (5) of the pile driver clamps the top of the upper casing, the bottom of the upper casing (42) is aligned with the top of the lower casing (41) and lowered until the lower edge of the limit ring (44) is close to the top of the lower casing (41); ② Start the vibrating hammer (5) to drive the upper casing (42) into the designed depth; (2) When the displacement of the top of the lower casing does not meet the design requirements, The completed lower casing (41) is the first lower casing. The deviation of the first lower casing is temporarily handled after the second lower casing is completed. The second lower casing adjacent to the deviation direction of the first lower casing is constructed according to step 3 and step 4. The displacement greater than the allowable deviation is adjusted by a hand chain hoist, or the deviation of the first lower casing under construction is adjusted by using the completed pile foundation. ① Use formula 1 to calculate the force required to adjust the top of the first lower casing to restore the deviation ,Preliminary selection of force application tools; Verify elastic rebound using formula 2 Meet design requirements; such as elastic rebound If the design requirements are not met, increase the force , until until; ② Tie the top of the first lower casing and the top of the second lower casing with steel wire rope; ③ Use a hand chain hoist to connect two steel wire ropes between the top of the first lower casing and the top of the second lower casing. Install a dynamometer on the hand chain hoist and record the reading of the dynamometer. The hand chain hoist restores the deviation of the first lower casing to the accurate position; if the pulling force of the hand chain hoist is too small to restore the first lower casing to the design requirement, use a winch to apply force to achieve the expected purpose. A dynamometer is also installed on the winch and the reading of the dynamometer is recorded; ④ The pile driver is positioned at the pile position where the deviation of the first lower casing does not meet the requirements, the upper casing (42) is hoisted, the vibrating hammer (5) of the pile driver clamps the top of the upper casing, and the bottom of the upper casing is aligned with the top of the lower casing (41) and lowered until the lower edge of the limit ring (44) is close to the top of the lower casing (41); ⑤ Release the force and drive the upper casing (42) into the designed depth; ⑥Measure the deviation of the top of the first upper casing to ensure that the deviation meets the design requirements; Before actual construction, the lower casing (41) and the upper casing (42) should be tested to obtain verification results of theoretical values ​​and actual values ​​and construction experience before formal construction to ensure the quality of the project; Step 6: Pour concrete and pull up the casing ①Select a circulation drilling rig suitable for on-site drilling and put the circulation drilling rig into place; ② Prepare sufficient quantity and qualified clay or bentonite drilling wall slurry to ensure appropriate slurry head in the steel casing; ③ When the drilling depth reaches the design requirements, check the hole depth, hole diameter, hole position and hole shape; ④ Use the grouting method to clean the hole and lower the steel cage; ⑤ One hour after the underwater concrete pouring is completed, when the concrete has reached the initial setting time but has not reached the final setting time, start the vibrating hammer and slowly lift the casing with a crane.

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