First, the steel bar into the factory and retest sampling

Steel after entering the construction site, the project department shall timely to fill in the inspection orders, including product name, origin, variety, specifications, models, stock number, date of purchase, the use of parts and yard, and 6 original quality certificate or product certificate, can be used when no original copies of dealer unit red chop on, Inform the supervision unit to conduct sampling and submit for inspection.

If there is a large number of samples of the same variety of materials, sample identification should be made, which includes specifications, models, batch numbers, sampling sites or use sites, etc., to avoid confusion among samples.

Second, construction machinery selection

According to the geological conditions of different sites, different hole forming machines are selected. Crawler long spiral multi-functional pile driver is commonly used, and vibration hammer, medium excavator and forklift are equipped.

Three, positioning measurement cable

1,Take the measurement control reference point submitted by the owner as the control point, establish the closed wire control network, Test the center point of the tank, and report to the supervision company for acceptance and signature approval, and then start to put the pile position.

2,According to the construction drawing, use the total station instrument or THEodolite, steel ruler to put the pile position, and make good records, check, recheck, by the supervision unit on-site acceptance.

3,The positions of the piles are marked with steel bars or bamboo sheets and protected to facilitate the positioning of the construction piles.

4,Generally, bamboo or steel head is used for pile placement. Each pile position should be marked with column position number.

5,Due TO the LARGE NUMBER OF PILE POSITIONS, a BENCHMARK PILE position MUST be placed at every TEN PILE positions. This benchmark pile position shall be placed by wooden piles and steel nails, and the pile position number shall be marked on the benchmark pile. This benchmark pile can be used to check the adjacent pile positions during construction.

Fourth, into a hole

1,Long auger bored pileAfter the rig was in place, the pre-check was conducted, and the deviation between the center of the drill bit and the pile position was less than20mm, and then adjust the drill, with double vertical ball two-way control of the vertical degree of drill pipe, qualified rear can be smoothly drilling. Close the bit seal when the bit is just touching the ground,The run rate is slow.

2,The normal drilling rate can be controlled at1～1.50m/min In the process of drilling, such as stuck drilling, drilling rig shaking, offset, should stop drilling to find out the reason, take corrective measures before continuing drilling.

3,The drilled earthwork should be cleaned in time and uniformly transferred to the designated place for stacking.

4,Use the hole depth mark on the drill pipe to control the drilling depth, drill to the depth and soil layer required by the design, and only after the on-site supervisor's acceptance can concrete pouring be carried out.

Five, concrete pump feed pile

1,The location of the ground pump should be reasonable, and the pipe conveying concrete should be bent as far as possible to facilitate the conveying of concrete.

2,The concrete entering the site must meet the design and specification requirements, and the concrete collapse degree should be controlled in180～220mmAnd has good workability, fluidity, on-site inspection of concrete collapse, unqualified requirements of concrete shall not be used in this project.

3,Pumping concrete should be carried out continuously, and the height of concrete in the ground pump hopper should not be lower than that in general40cmTo prevent air from being sucked into the pipe.

4,When the drill pipe is close to the ground, the pipe lifting speed should be slowed down and the hole residue should be cleaned in time to ensure the concrete quality of pile head.

5,A special person is responsible for observing the pumping pressure and drilling rig lifting. The drilling pipe lifting speed should match the pumping speed, and the perfusion lifting speed should be controlled at2.5m/min, it is strictly prohibited to lift the drill before filling, to ensure the quality of the pile, concrete perfusion must be poured to the surface.

6,Each pile machine each shift to produce a group of test blocks, and by the special person responsible for the production, maintenance and inspection according to the specification requirements, age28Day, the concrete test block specifications are:150×150×150mm.

Six, the production of steel cage

1, The production order of the steel cage is roughly the first to arrange the spacing of the main reinforcement, to be fixed to strengthen the stirrup, the main reinforcement and stirrup welding fixed, and then spot welding spiral stirrup.

2,The main rib lap adopts double-sided lap welding, and the joint length is5d, and ensure the concentricity of the main bars;

3,After the steel cage is made, the quality inspection form should be filled in truthfully, and it must be checked and approved by the supervision engineer before it can be used.

Seven, under the reinforcement cage construction

1,The pile machine is reformed to integrate the long spiral construction perfusion with the lower reinforcing cage, and cage insertion will begin immediately within three minutes after concrete perfusion to reduce the time difference and the difficulty of cage insertion.

2,After drilling holes with long auger bored piles and pouring concrete to the ground, the earth on the surface should be cleared in time, and the reinforcement cage should be inserted immediately. The qualified steel cage is set on the steel pipe, which is hung on the hook arranged on the flange with the wire rope.

3,Because the reinforcement cage is long, the reinforcement cage must be placed under the bidirectional perpendicularity observation, the use of bidirectional line vertical vertical arrangement, found that the deviation of the vertical degree is too large to inform the operator to stop the correction, the cage operators should align the reinforcement cage to the pile has been perfusion completed.

4,In the process of cage must first use vibration hammer and reinforcement cage self-pressure, pressure to press into the start of vibration hammer, to prevent vibration hammer vibration caused by the reinforcement cage offset, insertion speed should be controlled in1.2~1.5m/min.

5,After the steel cage is inserted into the design position, the power supply of the vibration hammer is turned off. Finally, the steel wire rope is removed, and the steel pipe and the vibration hammer are put out of the hole with a long screw drill3Open the vibration hammer once per meter to ensure the compactness of the concrete.

Viii. Construction process record

During the whole construction process, special personnel shall be assigned to monitor and make construction records, which shall be accurate and timely. Every root pile completed shall be submitted to the on-site supervision engineer for signature and acceptance.

Nine, pile head cleaning

After piling, the equipment and personnel should be organized to clear and discard the pile in a timely manner without affecting the subsequent piling. The completed pile body and reinforcing cage should be protected during the soil cleaning, and the discarded soil should be stacked to the designated place to ensure the continuous construction.

X. Pile foundation inspection

Construction of long auger bored perfusion pile has been completed28The test will be carried out after the next day, and the professional testing unit will carry out the test. The test pile position will be determined by the supervision unit and the construction unit after joint examination, and the construction unit will cooperate to make the pile cap.

Shanghai Qiangqiang Foundation Engineering Co., LTD. 's business covers foundation pit engineering, pile foundation engineering, land and waterFoundation treatment, slope treatment and other engineering fields. Around" Excellent technology, reliable process", construction fast "technical requirements,Is to provide customers with land, water foundation engineering technical consultation, construction services and other comprehensive solutions of the entity enterprise.Contact Number: 400-100-2850