3.4 the pier column and tie beam shall be poured simultaneously.
3.8 before the commencement of each bridge beam pier column, the test pier shall be made to check the formwork quality, concrete appearance quality, color, etc.
The removed scaffolds and formwork shall be stacked neatly and orderly.
After the fabrication of pier column and bent cap formwork, trial assembly shall be carried out to check the stiffness, flatness, joint tightness and structural size of the formwork, so as to avoid insurmountable defects and difficulties in the field use process.
Pier column construction procedure 3.
Insert the steel bar coarse head into the guide part of the wire rolling machine wheel from the through hole of the inner tailstock chuck and clamp it, and then start the automatic wire rolling head.
4.6 in principle, the pier column and bent cap concrete are not allowed to be modified, but if the main structure is not affected due to the defects on the concrete surface during the construction process, it shall be reported to the supervising engineer for approval before modification.
3.7 the scaffold erected by pier column and cap beam shall adopt buckle scaffold or 40 steel pipe scaffold, and the foundation at the lower part of the scaffold shall be dense, Square wood base plate shall be set, and the escalator for personnel to go up and down shall be considered for scaffold erection.
After the construction, the reserved holes shall be blocked with fine stone concrete.
Pier column and bent cap construction 1.
The scaffold shall be erected along with the construction progress.
The watering curing time of concrete is generally 7 days, which can be appropriately increased or shortened according to the air humidity and surrounding environment; When the temperature is less than 5 ℃, heat storage and curing shall be adopted.
Construction preconditions 1.1 the on-site safety and quality assurance system has been established, and the person in charge of the construction site and process has been defined.
3.5 the removal of formwork and support shall follow the sequence of first support and then removal, and the latter support and first removal.
1.6 the commencement report of subdivisional works has been approved, the labor force on the construction site meets the requirements of construction progress, and the construction schedule and construction scheme of subdivisional works have been approved.
3.6 if the shear pin scheme is adopted for the construction of tie beam and cap beam, the embedding of shear pin shall be smooth, straight and regular.
3.9 the connection of grade II reinforcement used for pier column and bent cap with a diameter of more than 25mm shall not be welded, but shall be mechanically connected, and the joint must be tested and accepted in accordance with relevant test specifications.
Construction quality 4.1 the allowable deviation of formwork installation of pier column and bent cap must comply with the following conditions: formwork elevation: ± 10mm; Internal dimension of formwork: ± 20mm; Axis deviation: 8mm 4.2 the concrete slump can be properly controlled according to the on-site air temperature.
4.7 the quality inspection items of pier column concrete pouring shall be in accordance with the evaluation standards..
The formwork shall be repaired and maintained in time, such as decontamination, rust removal and rust prevention.
The formwork shall not be connected with the scaffold to avoid formwork deformation.
Photos shall be taken and archived before modification, and the color of the decoration materials shall be consistent with the structure.
4.3 there is no crack on the concrete surface, no honeycomb and pitted surface, few water bubbles, flat, dense and smooth surface, uniform color of the concrete, no patchy pattern, no dislocation of formwork joints or construction joints, no slurry leakage, and the number of joints shall be at least.
A working platform shall be set at the top, and safety nets and guardrails shall be hung around.
Fixing Socket Waved End Nail Plate
the comprehensive construction can be carried out only after obtaining the approval.
It is strictly prohibited to fill with soil or sand, and the outside shall be consistent with the concrete color.
The formwork of slab pier can be fixed by tie rod or non tie rod formwork.
1.5 the design drawings and documents have been reviewed, the questions raised have been replied by relevant departments, and detailed technical disclosure has been made to the team.
3.10 when using forged coarse straight thread reinforcement joint, firstly, the die inner diameter of forging machine, the diameter of thread roller of wire rolling machine and the inner diameter of thread sleeve shall be controlled according to the negative deviation of the diameter of reinforcement raw materials of different brands; Next, cut the head 0.5~10mm on the grinding wheel cutting machine to achieve the end leveling, put the end of the steel bar into the mold cavity, and adjust the press pressure of the forging machine for forging and rough operation.
Construction technology and process 3.1 shaped large steel formwork shall be used for pier column and bent cap formwork.
3.2 for the construction of the bent cap of the consolidated pier, pay attention to the embedding of the reinforcement of the consolidated pier, and pay attention to the embedding of the bearing steel plate for the unconsolidated pier to ensure the accurate position.
4.4 special plastic cushion blocks shall be used to ensure that the protective layer of reinforcement meets the requirements, and there is no reinforcement leakage and block exposure on the concrete surface.
1.4 the foundation of the bridge has been tested, and the measurement and setting out of piers and bent caps have been completed.
After the formwork is removed, the structure shall be cured immediately to achieve the purpose of moisturizing and preventing pollution.
1.2 the required machinery and equipment are ready.
2.
3.3 the installation of formwork and reinforcement shall be carried out in cooperation.
After the concrete pouring is completed, the surface shall be covered and watered for curing immediately.
Generally, the concrete can be kept between 5 ~ 7cm in the formwork and 12 ~ 14cm in the pumping concrete.
4.
The escalator shall be equipped with guardrail, and the climbing angle of the escalator shall not exceed 45 degrees.
4.5 the concrete contour is clear, the line is straight, and there is no formwork warping.
The lower part shall be paved with wood boards not less than 5cm thick.
During design, the panel thickness of pier column formwork shall not be less than 5mm, the panel thickness of bent cap formwork shall not be less than 8mm, the rib plate design shall make the formwork have certain stiffness, it is not easy to deform during lifting and grouting, and the maximum deformation of panel shall not exceed 1.5mm.
The steel plate is embedded by fixing with the bent cap to keep the top surface of the steel plate horizontal.
1.3 all materials such as cement, sand, gravel and reinforcement have been mobilized, and the mix proportion has been determined.
Pull rod shall be pulled out after formwork removal, and PVC casing shall be cut along the surface of pier column.
Select the corresponding wire rolling wheel according to the steel bar specification and install it on the wire rolling machine.
The diameter of tie rod shall not be less than 16mm, and PVC pipe shall be sleeved on the outside.
It is strictly prohibited to leave it everywhere.
