Precast Concrete Connecting Beam Construction Technology

Precast concrete aerial connecting beam construction technology prefabricates the connecting beam into a PC structural beam through in-depth structural design, then hoists it through a tower crane and casts it partially in situ to complete the aerial connecting beam construction. Compared with the traditional full cast-in-situ scheme, this technology can speed up the construction progress and save construction costs such as manpower and materials.

Technical Process

1. Construction preparation

2. Pre-embedded structural steel bars and reserved bolt holes

3. Triangular support frame hoisting

4. Aerial connecting beam construction

5. Triangular support

PC beam prefabrication and triangular support frame welding

Operation Points

(1) Construction preparation

1) In-depth design

PC precast beam: Carry out in-depth design of PC precast beam according to the construction drawings.

Triangular support frame: Made of two No. 16 I-beams.

2) Material preparation

PC beam prefabrication is carried out on site using aluminum molds; the triangular support frame is welded by No. 16 I-beam and 20mm thick steel pad, and 3 bolt holes are opened on the steel pad.

(2) Pre-embedded structural steel bars and reserved bolt holes

During the construction of the structural layer where the aerial connecting beam is located, the connecting beam steel bars should be pre-embedded simultaneously, with a steel bar length of 500mm; at the same time, bolt holes should be accurately reserved on the wall-to-reinforce the triangular support frame.

(3) Hoisting of the triangular support frame

Use a tower crane to hoist the triangular support frame to the position of the structural bolt reserved hole, and install it on the shear wall with high-strength bolts to form a stable support platform.

(4) Construction of aerial connecting beams

PC prefabricated beams should be roughened before hoisting and then hoisted to the installed triangular support frame by a tower crane and manual labor. The position should be accurate; then the prefabricated beams and the reserved steel bars of the structure are welded, and the welding quality should meet the requirements; finally, the formwork reinforcement and concrete pouring of the cast-in-place beam section are completed, and the poured concrete should be one grade higher than the original design. Operators can stand on the structural cantilever frame or climbing frame for construction, and a hole is opened in the frame body at the connecting beam position for the hoisting of the PC prefabricated beam.

(5) Removal of the triangular support frame and formwork

When the concrete strength of the cast-in-place section reaches the requirements for formwork removal, workers can be arranged to remove the triangular support frame and formwork; the removed triangular support frame and formwork can be transferred to the upper structure for use.