Prefabricated stair component installation
1. Stair member installation process
Locating positioning → support the bottom of the stair beam, the inner mold and the template of the slow bench → lashing the bottom ribs and stirrups of the stair beam → installing the stairs support → installing the stairs → supporting the outer part of the stair beam → tying the upper part of the stepped plate and the stair beam Rebar → After the installation of the upper staircase is completed, this section of temporary slab and stair beam concrete shall be placed.
2. Stair member installation
1) Determine the horizontal and vertical height installation positions of the prefabricated parts of the staircase according to the control line, and use the ink line to project the stair at the top and bottom of the installation position on the shear wall of the stairwell. The top and bottom steps of the stair components are installed according to the construction location. Elevation control.
2) According to the structural elevation, support the bottom beam of the staircase beam, bind the bottom ribs and stirrups of the stair beam.
3) Firstly install the stair supports according to the installation position of the stair members, and support no less than two each.
4) Determine the lifting position of the stair element according to the position of the upper and lower stair beams.
5) Hang the hoisting wire rope symmetrically into the four embedded hanging points of the prefabricated stair components. Before the hoisting, try the stair components for trial hoisting. The stair components shall be lifted up to a height of 1 meter from the ground slowly, and the hoisting and mounting shall be performed after the correctness is confirmed.
6) After the stair elements are lifted to the stairs, the two are upright on both sides. One person will use the crowbar to stand on the stairs at the bottom of the stairs and aim at the upper and lower laminated beams to initially determine the position of the stairs.
7) Install 2 adjustable supports under the stair element. The upper part of the building runs one way and the lower one. The keel is placed on the support and the keel is arranged in a 10x10cm woodwork length.
8) Correct the components with a crowbar, and ensure that the stairs enter 1cm in the upper composite beam, and the prefabricated components reserve the steel reinforcements at the upper and lower superposed beam supports. According to the position of the building's elevation on the shear wall, check the exact height of the building. After the positioning of the stair components, no turbulence is allowed. After the hook is lowered, the adjustable support can be used to fine-tune the height difference.
9) Anchor the upper and lower prefabricated stairs in the reinforcement of the staircase beam to ensure the anchorage length.
10) Stair members shall be hoisted after checking the accuracy of the numbering of the stair components. When the stair components are lifted, they shall be tested and lifted. The lift shall be lifted slowly after being lifted from the ground with a height of 1 meter. The crane shall be lifted and lifted slowly at a height of 0.5 meters from the installation position. Stair members were lifted by 3 persons on the upper and lower sides of the stair component and on the inside, face up and upright so that the stair components were initially installed 2 cm into the cast-in-place beam.
11) According to the control line of the shear wall, the position of the stair member is conformed, and an adjustable support is used to fine-tune the elevation so as to ensure the installation position of the stair member is accurate.
12) Prefabricated components of the stairway Retain the anchoring steel bar into the stair beam to anchor it.
3. Staircase beam and slow bench
(1) Staircase girders and jogging decks include upper and lower stair girders and jogging decks.
(2) According to the structural elevation supporting the staircase plate, the bottom plate and the inner template of the staircase beam, the axis line of the stair beam and the control line of the elevation beam are projected to the shear wall before the supporting mold. quasi.
(3) First support the lower stair beam and then the upper stair beam. As the stair member and the stair beam meet on the outside, the outside of the stair beam is divided into two sections, that is, after the installation of the upper and lower running stair members, the two outer molds can be completed.
(4) Staircase girder and slow bench support are adjustable support. The keel adopts 10×10cm wooden side and the formwork adopts plywood.
(5) Tied the bottom ribs of the table top, pass the upper reinforcement of the staircase beam, and then tie the slower ribs on the upper part of the bench.
4. Staircase beam, slow bench concrete construction
1) After the stairs have been installed, pour the staircase beams and slow down the slab concrete.
2) Check that the upper and lower prefabricated stairs are anchored in the reinforcement of the staircase beam and the concrete is poured after the length of the anchorage is satisfied.
3) After the concrete is poured, cover it with plastic sheet.