- Zip code:23000
- Address:No. g097, floor 4, GF District, building 3, Wenshui road e-commerce Park, Hefei Economic Development Zone, Anhui Province
Reinforcement cage connection of bored cast-in-place pile
1. Scope of application
This process is applicable to the reinforcement cage extension of bored cast-in-place pile.
2. Process characteristics
2.1 simple construction, fast construction speed and mature technology.
2.2 the process level of reinforcement operation team is required to be high.
3. Process flow
3.1 fabrication and placement of reinforcement cage
3.1. 1. The reinforcement cage shall be fabricated by sections with full-automatic roll welding machine according to the design drawings and specifications,
The main reinforcement shall be connected by sleeve, the stiffener, stirrup and main reinforcement shall be spot welded, and the welded joints of reinforcement in the same section shall not be greater than 50% of the total joints.
3.1. 2. Mechanical connection or lap welding can be adopted for the connection between segmented reinforcement cages,
When lap welding is adopted, the main reinforcement shall be vertical and concentric, and the pre bending of the main reinforcement of the reinforcement cage shall be processed by hydraulic bending machine.
In order to facilitate welding and check the weld quality, single side welding is adopted for on-site welding, the weld length is 10d (D is the diameter of reinforcement), and the weld width B shall not be less than 0.8 times the diameter of main reinforcement. The weld thickness s shall not be less than 0.3 times the diameter of the main reinforcement;
The above longitudinal reinforcement joints shall be staggered every other, and the number of joints in each section shall not exceed 50% of the total.
The adjacent joints shall be staggered by 1.2m. The welding requirements shall meet the requirements of table 4.5.4 in the code for welding and acceptance of reinforcement (jgj18-2012). The concentricity requirements of reinforcement are shown in Figure 2-1.
When mechanical connection joints are used, positive and negative wires shall be used for butt joint, and the connection mode of "passing through wire and withdrawing half wire" is strictly prohibited
3.1. 3 when the reinforcement cage is lowered to the orifice, the main reinforcement shall be covered with PVC pipe above the pile cutting surface of the reinforcement cage, the pipe diameter shall be 5 ~ 8mm larger than the main reinforcement, the upper opening shall be folded and sealed, and the lower opening shall be sealed with Styrofoam to facilitate the stripping of pile head reinforcement during pile cutting in the later stage
3.1. 4. After the reinforcement at the reinforcement cage is processed, the cage body limit hanging reinforcement shall be installed,
Two main reinforcements are used for the limit hanging reinforcement, and the bottom spacing is 20cm. Three steel wire rope fixtures are used to fix it on the main reinforcement at the lower part of the reinforcement cage.
A hanging ring is set on the hanging reinforcement, and two parallel I-beams are inserted into it. Support the whole cage on the pile positioning support frame
The clear distance between two I-beams is 30cm larger than the outer diameter of the conduit. Then remove the lifting rope, draw a cross line on the reinforcement cage, find out the center of the reinforcement cage, find out the center of the pile position according to the pile casing positioning pile, combine and fix the center of the reinforcement cage and the center of the pile position, and fix the reinforcement cage in the center of the hole position.