CN101906776B - Major-diameter prestressed concrete pipe pile of glass steel pipe die and preparation method thereof - Google Patents

Abstract

The invention discloses a large-diameter prestressed concrete pipe pile with a glass steel pipe mold. The concrete lining is arranged in the glass steel pipe outer mold. Plates and steel plate ferrules are provided at both ends of the pile. The periphery is equipped with an assembled multi-segment steel casing working component that temporarily bears the prestressed tension anchorage force. The steel casing working component temporarily wraps the outer mold of the glass steel pipe, and the gap between the two is wedged tightly with a wooden triangle block. The casing working member bears the tension and anchoring force of the prestressed longitudinal reinforcement. The centrifuge rotates the steel casing working member to drive the outer mold of the glass steel pipe to rotate, and a large-diameter prestressed concrete pipe pile with any length of the pile body can be produced on site, overcoming The deficiencies of the traditional large-diameter pretensioned prestressed concrete pipe piles are fixed in length, the long-distance transportation of super-long pipe piles is difficult, the prestressed tendons are easy to corrode, and they are easy to crack during transportation and hoisting.

Description

Large-diameter prestressed concrete pipe pile with glass steel pipe mold and its preparation method

technical field

The invention relates to a concrete prefabricated pipe pile for civil engineering and a preparation method thereof, which is applied to foundation treatment in fields such as bridges and port engineering, and can conveniently manufacture pipe piles with arbitrary pile lengths on site.

Background technique

Steel pipe piles and prestressed concrete pipe piles are used as foundation treatment measures for many large bridges and port projects in coastal areas of our country. Steel pipe piles have the advantages of strong penetration capacity, high bearing capacity, small soil squeezing effect, convenient pile connection, strong horizontal bending resistance, and small hoisting weight. However, steel pipe piles are easy to corrode and expensive. Prestressed concrete prefabricated pipe piles have the advantages of low cost, convenient pile connection, short construction period, and easy guarantee of prefabricated quality, but they have high transportation costs, poor horizontal bending resistance, poor corrosion resistance, and are vulnerable to hammer sinking.

With the rapid development of long-span bridges and large-tonnage wharves, the demand for large-diameter and super-long pipe piles is increasing. Large-diameter super-long prestressed concrete prefabricated pipe piles are characterized by prefabricated pipe piles with a diameter of 800 mm to 1600 mm and a single section length of 30 meters to 50 meters. Traditional prestressed concrete prefabricated pipe piles are manufactured in factories, and the long-distance transportation of super-long pipe piles is difficult, and there are problems such as single mold specifications, fixed length of single-section pile body, pile connection or pile cutting, etc. The mold length of the pile is fixed The contradiction with the change of pile length in engineering design is particularly prominent.

In the field of civil engineering, there is an urgent need for a new type of large-diameter pipe pile with low price, arbitrary pile length, on-site fabrication, strong hammer resistance, high corrosion resistance, and high horizontal bending resistance. At present, in the field of civil engineering, large-diameter FRP sand-filled pipes and FRP composite pipes have been widely used. They have the characteristics of good corrosion resistance, light weight and high strength, long service life, many specifications, and low prices. Large-diameter fiberglass steel pipes are used as the external formwork of prefabricated pipe piles, and the assembled and assembled multi-segment steel casing working components (one segment is about 2m to 3m long, flanged connection) are arranged around the periphery to temporarily bear the prestressed tension anchorage force. The centrifugal manufacturing process of concrete pipe piles can produce "large-diameter prestressed concrete pipe piles with glass steel pipe molds" with any length of pile body on site. The pile body is composed of inner and outer layers, the outer layer is a glass steel pipe mold, and the inner layer is a prestressed concrete lining. The pile of the invention has the advantages of high bearing capacity, arbitrary pile length, few joints, low cost, strong anti-corrosion performance, large horizontal bending bearing capacity, strong hammering resistance, high penetration capacity and the like. The pile of the present invention can be fabricated on site, and overcomes the fixed length of a single section of the pile body (the fixed length of the mold remains unchanged) of the traditional large-diameter pretensioned concrete pipe pile, the difficulty of long-distance transportation of the super-long pipe pile, high transportation costs, and prestressed tendons. Easy to rust, easy to crack during transportation and hoisting and other shortcomings.

Contents of the invention

Technical problem: The present invention provides a large-diameter prestressed concrete pipe pile with glass steel pipe mold and its preparation method. The invention has the advantage of strong capacity, and the preparation method can manufacture prestressed concrete pipe piles with arbitrary pile lengths.

Technical solutions:

The large-diameter prestressed concrete pipe pile of a glass steel pipe mold according to the present invention comprises: a glass steel pipe outer mold, a concrete inner lining, a steel end plate and a steel plate hoop, the concrete inner lining is arranged in the glass steel pipe outer mold, A steel skeleton composed of prestressed longitudinal bars and spiral stirrups is arranged in the concrete lining. Steel end plates are arranged at both ends of the pile. Between them, the prestressed longitudinal reinforcement header is anchored in the anchor hole of the steel end plate.

The working component of the steel casing temporarily wraps the outer mold of the glass pipe, and the gap between the two is wedged tightly with a wooden triangular block. The working component of the steel casing bears the tension and anchoring force of the prestressed longitudinal reinforcement, and the working component of the steel casing is rotated by a centrifuge. , to drive the outer mold of the glass steel tube to rotate.

The preparation method of the large-diameter prestressed concrete pipe pile of the glass steel pipe mold of the present invention,

Step 1: According to the design length of the pipe pile, carry out the blanking of the outer mold of the glass steel pipe and the prestressed longitudinal reinforcement. After the prestressed longitudinal reinforcement is heading, the prestressed longitudinal reinforcement and the spiral stirrup are welded to form a pile by rolling welding into a cage. The steel frame is positioned and placed in the outer mold of the glass steel pipe, and steel end plates and steel plate hoops are installed at both ends. According to the volume requirements of the concrete lining, the fresh concrete is poured into the outer mold pipe of the glass steel pipe with a pump guide;

Step 2. Assemble and assemble multi-segment steel casing working components on the periphery of the outer mold of the glass steel pipe. Each steel casing working component has a segment length of 2m to 3m and is connected by a flange. The outer mold of the glass steel pipe is connected to the steel casing. The gap between the temporary workpieces is wedged tightly with wooden wedges;

Step 3 Connect the tension rod with the steel end plate, connect the tension rod with the prestressed anchor plate, and use the jack to stretch the prestressed longitudinal reinforcement through the tension rod. After the tension reaches 70% of the strength of the reinforcement, use a large nut to tighten The pull rod is fixed on the prestressed anchor plate at the tail of the steel casing workpiece;

Step 4: Lift the centrifuge into place, and the centrifuge rotates the steel casing workpiece, which drives the outer mold of the glass steel pipe to rotate, and the concrete lining is centrifugally shaped. After steam curing, the prestress is released, demoulded, and the pipe pile is formed.

The outer mold of the FRP pipe is a large-diameter FRP sand-filled pipe or a finished FRP composite pipe.

The working component of the steel casing is an assembled multi-segment steel casing, each segment is 2m to 3m long, the segments are connected by flanges, and the ends are equipped with tension anchors that bear the prestressed tension anchor force. plate.

According to the design length of the pipe pile section, select the appropriate FRP composite pipe material with sand, and at the construction site, carry out the blanking of the outer mold of the FRP pipe; stir the adhesive interface agent evenly on the spot, pour it into the outside 1 of the FRP pipe, and use centrifugal The adhesive interface agent is applied evenly along the pipe wall, and the inner surface of the outer mold of the glass steel pipe is roughened; according to the design strength requirements of the concrete lining, sand, stone, cement, water, superplasticizer and active powder Accurate measurement for high-strength concrete preparation; prestressed longitudinal reinforcement is made of PC steel rod material, and the prestressed longitudinal reinforcement is accurately lengthened, cut, and heading according to the length of the pile body segment, and the spiral stirrup is selected from cold-drawn low-carbon steel wire or low-carbon steel wire Carbon steel hot-rolled disc steel bars are rolled into a cage by seam welding, and the prestressed longitudinal bars and spiral stirrups are welded to form a steel bar skeleton for the pile body; Steel plate ferrule, the inner sleeve of the steel plate ferrule is inserted into the outer mold of the glass steel pipe, and high-strength slow-setting structural adhesive is filled between the outer mold of the glass steel pipe and the steel plate hoop; according to the volume requirement of the concrete lining, the fresh concrete is poured with a pump guide Fill the lower half of the pipe evenly along the glass fiber reinforced plastic composite pipe with sand, and spread as much concrete as possible on the stretched end; the outer periphery of the glass steel pipe is equipped with assembled multi-sections that undertake prestressed tension anchorage Segmental steel casing working components (a segment length of about 2m ~ 3m, connected by flanges) form a temporary workpiece of steel casing, using wedge blocks to wedge the gap between the outer mold of the glass steel pipe and the temporary workpiece of steel casing; The end plate is connected with the tension rod, and the tension rod is connected with the anchor plate of the steel casing temporary workpiece. Through the tension rod, the jack is used to stretch the prestressed longitudinal reinforcement. After the tension reaches 70% of the strength of the reinforcement, use a large nut to tighten The pull rod is fixed on the anchor plate of the steel casing workpiece; the centrifuge is hoisted in place, and the centrifuge rotates the steel casing workpiece, driving the outer mold of the glass steel pipe to rotate, and accelerating step by step according to the initial speed, medium speed, medium high speed, and high speed. The freshly mixed concrete is evenly compacted along the pipe wall of the outer mold of the glass steel pipe, and the pipe pile concrete is centrifugally set, and the centrifugal time is generally 10min to 20min; the centrifugal pipe pile with mold after centrifugal formation is hoisted into the atmospheric pressure steam curing pool (pit) , stop for 1 hour, slowly raise the temperature to 90°C-100°C, and maintain it under normal pressure for 6h-8h, so that the concrete strength can reach more than 40MPa; remove the tension bolts and mold clamping bolts with a pneumatic wrench, and perform tensioning and demoulding. Make the pile body prestressed; hoist the centrifugal pile into the autoclave for high-temperature steam curing, the maximum temperature is 180°C-200°C, the saturated steam pressure is 1.0MPa, and the curing time is 8h-12h, so that the concrete strength can reach more than 80MPa. The cured pipe piles can be directly delivered to the factory for piles.

The large-diameter prestressed concrete pipe pile with glass steel pipe mold, the pile body is composed of inner and outer layers, the outer layer is a glass steel pipe outer mold, and the inner layer is a prestressed concrete lining. Large-diameter fiberglass steel pipes are used as the external formwork of prefabricated pipe piles, and the assembled and assembled multi-segment steel casing working components (one segment is about 2m to 3m long, flanged connection) are arranged around the periphery to temporarily bear the prestressed tension anchorage force. Concrete pipe pile centrifugal manufacturing process, the large-diameter prestressed concrete pipe pile with any length of pile body can be produced on site.

The pile of the invention has the advantages of high bearing capacity, on-site fabrication, strong anti-corrosion performance, large pile body anti-bending bearing capacity, optional pile length, fewer pile welding joints, low cost, strong hammering resistance, and high penetration ability. The pile of the present invention overcomes the fixed length of the pile body of the traditional large-diameter pretensioned prestressed concrete pipe pile (the fixed length of the mold remains unchanged), the difficulty of long-distance transportation of the super-long pipe pile, high transportation costs, easy corrosion of prestressed tendons, and difficulty in transportation and hoisting. Easy to crack and other deficiencies. At the tip of the pile, it can be easily welded with steel pipe piles or steel pile shoes.

Beneficial effects: the new pile type of large-diameter prestressed concrete pipe pile of glass steel pipe mold of the present invention is applied to pile foundations in buildings, bridges and port engineering, and can replace bored piles, steel pipe piles, and prestressed concrete pipe piles . The pile body of the pile of the invention is composed of inner and outer layers, the outer layer is a glass fiber reinforced plastic sand-inserted composite pipe, and the inner layer is a prestressed concrete inner lining. Large-diameter glass pipes are used as the outer formwork, and the assembled and assembled multi-segment steel casing working components (one segment is about 2m to 3m long, flanged connection) are arranged on the periphery to temporarily undertake the prestressed tension anchorage, and the concrete pipe is centrifugally manufactured. The pipe pile of any length can be conveniently made by using the technology, and the pipe pile can be made on site or in the factory. The pile of the invention has the advantages of high bearing capacity, strong anti-corrosion performance, large bending bearing capacity, strong hammering resistance, high penetration capacity, arbitrary pile length, on-site fabrication, and low cost. Pile of the present invention is owing to adopt glass fiber reinforced plastics sand-inserted composite pipe as outer formwork, thereby, can make on-the-spot (can reduce transportation workload), pile length is arbitrary, has overcome the pile body length fixing of traditional large-diameter pretensioning method prestressed concrete pipe pile ( The fixed length of the mold remains unchanged), the long-distance transportation of super-long pipe piles is difficult, the transportation cost is high, the prestressed tendons are easy to corrode, and they are easy to crack during transportation and hoisting. Compared with steel pipe piles, it has good anti-corrosion performance, high durability and low maintenance cost; compared with traditional prestressed concrete pipe piles, it has the advantages of high horizontal bending resistance, simple manufacturing process, and good anti-corrosion durability. The FRP composite pipe with sand in the outer layer of the pile in the present invention is equivalent to increasing the reinforcement amount of the vertical ordinary steel bar and the hoop stirrup of the pipe pile, and its bending resistance is greatly improved compared with the ordinary prestressed concrete pipe pile, avoiding the need for long To solve the problem of cracking in pile hoisting, the length of a single section of pipe pile can be significantly increased; the spacing of the spiral stirrups in the concrete lining can be appropriately enlarged to reduce the amount of stirrups; Hammer resistance and penetration of concrete pipe piles. The piles of the invention are especially suitable for large-diameter super-long pile foundation projects in large-span bridges, large-tonnage wharves and marine engineering.

Description of drawings

Figure 1 is a schematic diagram of a section of pile reinforcement;

Fig. 2 is the schematic diagram of pile body preparation method;

Fig. 3 is a pile body section schematic diagram;

Figure 4 is a large sample diagram of the pile body end node.

In the figure: glass steel pipe outer mold 1; concrete lining 2; prestressed longitudinal reinforcement 3; spiral stirrup 4; steel end plate 5; 9. Tension rod 10, prestressed anchor plate 11.

Detailed ways

Example 1

A large-diameter prestressed concrete pipe pile with a glass steel pipe mold, which is characterized in that it includes: a glass steel pipe outer mold 1, a concrete lining 2, a steel end plate 5 and a steel plate hoop 6, and the concrete lining 2 is arranged outside the glass steel pipe Inside the formwork 1, a reinforced skeleton composed of prestressed longitudinal reinforcement 3 and spiral stirrup 4 is arranged in the concrete lining 2, steel end plates 5 are arranged at both ends of the pile, and the steel plate hoops 6 are arranged on the steel end plates 5 And it is located between the glass steel pipe outer mold 1 and the concrete inner lining 2 , and the prestressed longitudinal reinforcement 3 is anchored in the anchor hole of the steel end plate 5 .

The steel casing working member 7 temporarily wraps the glass steel pipe outer mold 1, and the gap between the two is wedged tightly with a wooden triangle block. The steel casing working member 7 bears the tension and anchoring force of the prestressed longitudinal reinforcement 3, and the centrifuge rotates the steel pipe. The casing working member 7 drives the outer mold 1 of the glass steel pipe to rotate.

The outer mold of the FRP pipe is a large-diameter FRP sand-filled pipe or a finished FRP composite pipe.

Example 2

A method for preparing a large-diameter prestressed concrete pipe pile with a glass steel pipe mold, the main steps are as follows:

Step 1: According to the design length of the pipe pile, the outer mold 1 of the glass steel pipe and the prestressed longitudinal reinforcement 3 are blanked. The ribs 4 are welded to form the reinforcement skeleton of the pile body. The reinforcement skeleton is positioned and placed in the outer mold 1 of the glass steel pipe, and steel end plates 5 and steel plate hoops 6 are installed at both ends. Pour into the glass steel pipe outer mold 1 pipe;

Step 2: On the periphery of the glass steel pipe outer mold 1, assemble and assemble multi-segment steel casing working members 7, each steel casing working member 7 has a segment length of 2m to 3m, connected by a flange 9, and the glass steel pipe outer mold 1 and the gap between the steel casing temporary workpiece 7, use a wooden wedge block 8 to wedge tightly;

Step 3: Connect the tension rod 10 to the steel end plate 5, connect the tension rod 10 to the prestressed anchor plate 11, and use a jack to stretch the prestressed longitudinal reinforcement 3 through the tension rod 10 until the tension reaches 70% of the reinforcement strength , fix the tension rod 10 on the prestressed anchor plate 11 at the tail position of the steel casing workpiece 7 with a large nut;

Step 4: hoist the centrifuge into place, and the centrifuge rotates the steel casing workpiece 7, which drives the glass pipe outer mold 1 to rotate, and the concrete lining 2 is centrifugally shaped. After steam curing, the prestress is released, demoulded, and the pipe pile is formed.

The working component of the steel casing is an assembled multi-segment steel casing, each segment is 2m to 3m long, the segments are connected by flanges, and the ends are equipped with tension anchors that bear the prestressed tension anchor force. plate.

The present invention is described in more detail below:

Large-diameter prestressed concrete pipe piles with glass steel pipe molds can be mass-produced on site or in factories. The piles of the invention are suitable for pile foundation projects of large bridges or large-tonnage wharves, so as to exert their advantages. The diameter of the pipe pile should be 800mm-1600mm, and the length of the prefabricated single-section pile should be 30m-50m, and the length of each section should be 20-30 times the pipe diameter. The construction process is as follows: concrete preparation - rough treatment of the inner surface of the glass steel pipe - making of the steel skeleton - the steel skeleton enters the glass steel pipe mold - installation of steel end plates and steel plate hoops - pump pipes to guide concrete distribution - on-site assembly Steel casing workpiece—prestressed tension—centrifugal setting—primary steam curing—tensioning and demoulding—high pressure steam curing—hoisting and transportation—welding piles—pile sinking construction. In the on-site production or factory production of large-diameter prestressed concrete pipe piles of glass steel pipe molds, attention must be paid to each link. The specific production process points are as follows:

(1) Preparation of high-strength concrete

According to the designed mix ratio, the sand, stone, cement, water, high-efficiency water reducer and microsilica admixture are accurately measured, and the fresh mix with a low slump of 5cm to 8cm is made with a concrete forced mixer. Concrete, the design requires that the concrete strength grade is not lower than C60 or C80.

(2) Rough treatment of the inner surface interface of the glass steel pipe

The adhesive interface agent should be composed of water-based adhesive, high-grade cement, fine quartz sand, fly ash, micro silica fume, high-efficiency water reducer, expansion agent, etc. The adhesive interface agent should be stirred evenly and poured into the FRP composite pipe with sand , using the centrifugal process, the adhesive interface agent is spread evenly along the tube wall. When the outer mold is a FRP-PVC composite pipe, the PVC inner pipe wall should have thread grooves, and the friction between the concrete lining of the pipe pile and the inner surface of the FRP-PVC composite pipe increases, and the two work better together.

(3) Fabrication of steel skeleton

The prestressed main reinforcement adopts low relaxation prestressed concrete steel rods (PC steel rods). With good spot welding properties, PC steel rods should be accurately lengthened, cut, and heading. The spiral stirrup adopts cold-drawn low-carbon steel wire or low-carbon steel hot-rolled disc steel bar with a diameter of 5mm-8mm. The outer diameter of the pile is 800mm-1000mm, and the diameter of the spiral reinforcement should not be less than 5mm; It should not be less than 6mm; the outer diameter of the pile should be 1200mm to 1600mm, and the diameter of the spiral reinforcement should not be less than 8mm. The maximum thread pitch of the steel frame should not exceed 200mm. The distance from both ends of the pile is within the length range of 1000mm to 1600mm, and the pitch is 75mm to 100mm. The steel skeleton of the pipe pile adopts the cage welding process.

(4) The steel skeleton enters the glass steel pipe mold

The process of wrapping glass fiber on the outer layer of large-diameter plastic pipes has matured, and large-diameter FRP composite pipes with sand have been widely used. They have the characteristics of good corrosion resistance, light weight and high strength, long service life, many specifications, and low prices. The lining plastic of the FRP composite pipe can be polyvinyl chloride, polyethylene or polypropylene plastic pipe, and the inner plastic pipe has thread grooves. In order to increase the friction between the pile and the soil, the outer surface of the FRP composite pipe with sand should be provided with threaded grooves. In order to increase the friction between the concrete lining and the FRP composite pipe, the inner surface of the FRP composite pipe should have thread grooves.

When the steel skeleton enters the FRP composite pipe mold, it should be centered. Using spacers, locate cover thickness.

(5) Install steel end plates and steel hoops

Put the prepared FRP sand-filled composite pipe, steel frame, and steel end plate (welded hoop) in place according to the drawing. The steel frame should be positioned accurately with positioning pads in the FRP composite tube, and the steel end plate and steel plate sleeve should be installed. hoop, the steel plate hoop should be set inside the FRP sand composite pipe mold, and the high-strength slow-setting structural adhesive should be filled between the FRP sand composite pipe and the steel hoop plate, the FRP composite pipe and the steel end plate should be tightened, and the steel end The plate is connected with tension rods, prestressed steel anchor plates, etc.

(6) Pump pipe guide grouting concrete distribution

According to the requirement of the amount of fresh concrete for each centrifugal pipe pile, use the pump pipe to pour the fresh concrete into the FRP sand-filled composite pipe, fill the lower half of the pipe evenly along the FRP sand-filled composite pipe, and spread as much as possible on the stretching end concrete.

(7) Assembled steel casing workpiece

The periphery of the FRP sand-filled composite pipe is equipped with an assembled multi-segment steel casing working component that undertakes prestressed tension and anchorage. The segment casings are connected by flanges and bolts. The sleeve can bear the prestressed tension anchorage force. Use wedges to wedge the gap between the FRP sand-infused composite pipe and the peripheral steel casing to ensure that the FRP sand-included composite pipe is driven to rotate synchronously during centrifugal rotation.

(8) Prestressed tension

The jack-type tensioning machine is used to overall tension the reinforced skeleton of the centrifugal pipe pile after mold closing. After the tension reaches 70% of the strength of the steel bar, the tension rod is fixed on the steel casing anchor plate with a large nut.

(9) centrifugal setting

Lift the centrifugal pipe pile with assembled steel casing mold workpieces above the centrifuge, and accelerate step by step according to the centrifugal speed of initial speed, medium speed, medium high speed and high speed, and the centrifugation time is generally 10min to 20min. Through the centrifugal compacting forming process, the fresh concrete is evenly compacted along the outer surface of the FRP composite pipe with sand. After centrifugation, raise the tension end and dump the waste slurry water generated during centrifugation.

(10) primary steam curing

Hang the molded centrifugal pipe pile after centrifugation into the atmospheric pressure steam curing pool (pit), stop for 1 hour, slowly raise the temperature to 90°C-100°C, and maintain it under atmospheric pressure for 6h-8h, so that the concrete strength can reach more than 40MPa.

(11) Zhang Zhang, demoulding

Hoist the molded centrifugal pipe pile after primary steam curing to the special demoulding platform, remove the tension bolts and mold clamping bolts with a pneumatic wrench, so that the pile body is prestressed, and then hoist the casing mold. Clean casing molds, anchor plates, and tension rods. For the centrifugal pipe piles whose concrete design strength grade is C60, the demoulded centrifugal pipe piles are directly hoisted to the finished product yard for natural curing, and can be shipped out after reaching the factory strength.

(12) Autoclaving

Centrifugal pipe piles whose design concrete strength grade is above C80 need to put the demoulded centrifugal pipe piles into the autoclave for high-temperature steam curing. The maximum temperature is 180℃～200℃, the saturated steam pressure is 1.0MPa, and the curing time is 8h～ 12h, make the concrete strength reach more than 80MPa. The pipe piles after high pressure curing can be directly delivered to the factory for piles.

(13) Hoisting and transportation

The large-diameter prestressed concrete pipe pile of the glass steel pipe mold has a large flexural bearing capacity and cracking moment. The performance is greatly improved compared with ordinary prestressed concrete pipe piles. Therefore, the length of a single section of pipe pile can be significantly increased to reduce on-site splicing joints and facilitate construction. It is recommended that the prefabricated length of a single section be 20 to 30 times the pipe diameter; diameter 800mm- pile length 16m to 24m, diameter 1000mm- pile length 20m to 30m, diameter 1200mm- pile length 24m to 36m, diameter 1400mm- pile length 28m to 42m, diameter 1600mm - pile length 32m ~ 48m. When the pipe pile is hoisted, the two ends of the pipe pile can be easily lifted by hooking the two ends of the pipe pile with a special hook. Large-diameter prestressed concrete pipe piles of glass steel pipe molds should be fabricated on site and transported by floating.

(14) welding pile

The welding construction of pipe piles should be carried out in accordance with the specifications. When welding piles, the center of pipe piles should be aligned up and down, positioned with a temporary locator, and temporarily fixed by spot welding at 4 to 6 places, and the pipe pile joints are welded. There should be no less than 3 passes, and all welds should be firm and full without welding defects such as slag inclusions.

(15) Pile sinking construction

The large-diameter prestressed concrete pipe piles of glass steel pipe molds can be piled by hammering piles or static pressure piles, and the pile ends can be made into open types or pile tip types.

Claims (1)

1. a kind of preparation method of the large-diameter prestressed concrete pipe pile of glass steel pipe mold, it is characterized in that, Step 1: According to the design length of the pipe pile, the glass steel pipe outer mold (1) and the prestressed longitudinal reinforcement (3) are blanked. After the prestressed longitudinal reinforcement (3) is headed, the prestressed longitudinal The longitudinal bars (3) and the spiral stirrups (4) are welded to form the reinforcement skeleton of the pile body, and the reinforcement skeleton is positioned and placed in the outer mold (1) of the glass steel pipe, and steel end plates (5) and steel plate hoops (6) are installed at both ends, According to the volume requirement of the concrete inner lining (2), the freshly mixed concrete is poured into the pipe of the glass steel pipe outer mold (1) with a pump guide; Step 2 Assemble and assemble multi-segment steel sleeve working components (7) on the periphery of the glass steel pipe outer mold (1). 9) Connection, the gap between the glass steel pipe outer mold (1) and the steel sleeve working member (7) is wedged tightly with a wooden wedge (8); Step 3 Connect the tension rod (10) to the steel end plate (5), connect the tension rod (10) to the prestressed anchor plate (11), and use a jack to lift the prestressed longitudinal reinforcement (3) through the tension rod (10). Tensioning, after stretching to 70% of the strength of the steel bar, use a large nut to fix the tensioning rod (10) on the prestressed anchor plate (11) at the tail position of the steel casing working member (7); Step 4: Hoist the centrifuge into place, and the centrifuge rotates the working component of the steel casing (7), driving the outer mold of the glass steel pipe (1) to rotate, and the concrete lining (2) is centrifugally shaped, and after steam curing, the prestress is released and demoulded , pipe pile forming, The glass steel pipe outer mold (1) is a large-diameter glass fiber reinforced plastic sand pipe or a finished glass fiber reinforced plastic composite pipe.

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