1. This capping beam adopts No.36 I-beam as the load-bearing beam during capping beam construction. I-beam is supported by clamps, which are fixed on pier columns, and each pier column is provided with a clamp. I-beam is close to both sides of pier, and I-beam is fixed with φ 16 tie rod. After the I-beam is accurately positioned, the truss pieces are used to strengthen the bar as the bottom support, and the spacing is 60 cm.

2. After the pier concrete curing is completed and the strength reaches the design strength, remove the curing film, remove the clamp, remove the elevation of the bottom plate of the capping beam on the pier, and put a circle of gauze around the clamp position to avoid the clamp leaving traces at this position.

3. Pay off the capping beam accurately on the construction platform, and lay the finalized bottom die. Joints and flatness shall meet the requirements of specifications, and the dimensions and elevations shall be consistent with the dimensions and elevations of the bottom of the capping beam designed in the drawings.

4. Between columns, φ273mm steel pipes are used to support the hoop bottom and the middle part of I-beam, so as to prevent the bottom of the capping beam from deflecting during concrete pouring.

5. The construction operation platform is located on both sides of the capping beam, each side is 70cm, and the capping beam is fortified and blocked to prevent personnel and sundries from falling.

6. Chisel away the top of the pier and correct the steel bar at the top of the pier, make a steel skeleton in the steel yard, lift the steel skeleton with a crane as a whole and locate it accurately to ensure the thickness of the protective layer at the bottom and side of the steel bar.

6. 1. Chisel away the top of pier column and correct the steel bar at the top of pier column, mark the position of each steel bar skeleton on the bottom formwork of capping beam, support and mark the position of the steel bar skeleton at the top of pier column.

6.2. On-site production of steel reinforcement skeleton, the production sequence is first frame and then local frame. The size and quality of the skeleton should meet the specifications and design requirements.

6.3. After the skeleton production is completed, it will be transported to the capping beam by flatbed truck, and the steel skeleton will be lifted by crane piece by piece, accurately positioned, so as to ensure the thickness of the protective layer at the bottom and side of the steel bar. The construction operation platform is located on both sides of the capping beam, 70cm on each side, and the capping beam is fortified to prevent personnel,

Sundries fall.

6.4. After the skeleton reinforcement is in place, tie the stirrups. When binding stirrups, we should pay attention to the stirrup spacing and adjust the main reinforcement spacing to meet the specification requirements.

6.5. The intersection of steel bars shall be firmly bound with iron wire, and the binding head shall be bent to the inside of the skeleton to avoid stabbing the construction personnel.

6.6. After the processing of main reinforcement is completed, tie the capping beam at the edge of large pile number and heighten the reinforcement.

6.7. After the overall steel binding is completed, it shall be submitted to the supervision engineer for inspection. After the inspection is qualified, the capping formwork shall be installed.

6.8. After the capping beam formwork is erected, the cushion block and supporting cushion stone reinforcement shall be embedded, and the supervision engineer shall check the template size, elevation, flatness, axis deviation, plane position, embedded parts position and protective layer, and concrete shall be poured after inspection.

6.9. After the capping beam construction is completed, accurately pay off the capping beam, adjust the cushion stone reinforcement, and conduct the second pouring.

7. The steel bar shall not be shuttered until it is inspected by the supervision engineer. The side formwork is an integral steel formwork with sufficient rigidity. Threaded holes are left between the side formwork and the bottom formwork, and the two formworks are connected by adhesive tape and bolts to prevent slurry leakage. After the side formwork is installed in place by crane, install the top tie rod to correct the verticality and axis deviation of the side formwork. In order to prevent the overall deviation during concrete pouring, two φ8mm steel wire ropes are used to pull the cable wind rope at the upper mouth of the side formwork, and the horizontal angle of the cable wind rope is 45 degrees.

8. For the embedded block and cushion stone reinforcement, report to the supervision engineer to check the template size, elevation, flatness, axis deviation, plane position, embedded parts position and protective layer, and start pouring concrete after passing the inspection.

9. Slump should be strictly controlled during concrete pouring, and concrete should be pumped to ensure that the slump of concrete is not greater than 16cm. The concrete delivery pump pipe is supported by the set-up special support, and shall not touch the formwork and bottom formwork top bracing. Vibrating adopts two plug-in vibrators with a diameter of 5cm to vibrate in layers with a thickness of 30cm, and each vibrating is inserted into the lower layer by 5- 10cm.

Vibrate until the concrete surface is submerged and no bubbles emerge, but it is necessary to prevent over-vibration. The elevation of concrete top surface shall be strictly controlled and shall not be higher than the design capping beam top elevation. When pouring, there should be a special person to check the bracket and template at any time to prevent the bracket from loosening and the template from running out of position during pouring.

1 1. Immediately after pouring, clean the concrete slurry sprinkled on the surface of the column and ribbed wall during construction with a water pump to ensure the appearance quality of the column and ribbed wall.

12. When the strength of the capping beam reaches 2.5MPa, dismantle the side formwork. When the formwork is removed and lifted by crane, pay attention to prevent the formwork from damaging the external surface and edge of concrete. The bottom die can only be removed after the capping beam reaches the design strength 100%.

13. Cover the capping beam with wet sacks and spray water for curing. The curing time shall not be less than 7 days. If the temperature is too low, anti-freezing measures should be taken for maintenance, such as wrapping with plastic film, using hot water inside and using steam for maintenance.

14. After the capping beam construction is completed, pay-off shall be accurately carried out on it, and the second cushion stone shall be poured. The smoothness of the cushion stone surface is controlled within 2mm, which is convenient for the next bearing construction.

15. Because the capping beam is a transition pier capping beam, considering the cast-in-place to cast-in-place box girder construction, it will be poured twice, with the first pouring of 1.5m, that is, the design elevation of cast-in-place box girder; For the second time, the cast-in-place box girder reinforcement shall be poured after the completion of the first section.