2. Before installation, the quality of the previous procedure should be reinspected, and the components can be installed only after passing the inspection. After installation, check the position, elevation and stability of components.
3. Precast curved beams should be hoisted at three points, and temporary supports should be set in the middle of the span after they are in place, and they can not be removed until the upper second-stage concrete reaches more than 75% of the design strength. The included angle between the hanging rope and the plane of the prefabricated part shall not be less than 45 degrees, and when it is less than 45 degrees, the strength shall be checked (the assembled beam and slab of the bridge shall not be less than 60 degrees, and hangers or poles shall be added when it is less than 60 degrees).
Second, the cast-in-place wallboard joint concrete
1. The inner formwork is installed to the top at one time, and the outer formwork is supported by sections when pouring. The height of the section shall not exceed1.5m. 。
2. The concrete adopts micro-expansive quick-setting cement, which is one grade higher than the strength of wallboard concrete.
3. When the joint width of wallboard is large, the thickness of concrete layered pouring should not exceed 250mm (the cast-in-place concrete wallboard is not more than 500mm).
Third, the steel wire winding prestressed construction
1, prestressed steel wire joints should be tightly bound, and the lap length should not be less than 250 mm
2, winding prestressed steel wire from the top of the pool wall downward, the distance from the top of the pool for the first time should not be greater than 500 mm..
3. The parts at both ends of the pond wall that cannot be wound by the wire winder should be locally encrypted near the top and bottom or tightened by electric heating.
4. Before winding wires on the pool wall, protective railings should be set around the pool wall.
5. Electrothermal tensioning: 1) starts from the top of the pond wall and goes down one ring at a time; 2) The allowable deviation of elongation control shall not exceed 6%; 3) Tension is completed at one time, and the number of repetitions of the same steel bar shall not exceed 3 times; 4) Stress measurement: After the initial stress is established, the initial reading is measured before the power is turned on, and the final reading is measured after the power is turned off and cooled.
Four, cement mortar protective layer construction
1, after full water test, and in full water state.
2. The spraying should be carried out from top to bottom, and the construction should be carried out when the temperature is higher than 15 degrees, and the construction should not be carried out in gale, rainstorm and freezing above level 6.
3. The thickness should be 50mm, and it should be covered with moisture for not less than 14 days after condensation. Before the next process, check the appearance and adhesion.