What are Construction Steps and Precautions for Movable Scaffolding System?

Movable scaffolding system

Construction steps and precautions

1. Construction steps

1.1 Movable scaffolding system main girder falls down, be divided, moves laterally

1.1.1 Remove suspender of rear anchoring device

1.1.2 Remove home-made bulk formwork at the top of pier;

1.1.3 Meanwhile steel box girder support jacks fall. The formwork separates from poured concrete girder, steel box girder is supported on support roller of longitudinal moving gearbox; remove formwork at centerline of MSS and connection bolts of cross girder. Check whether connection between formwork lateral moving device and left, right parts of formwork is been removed totally, little lateral moving divides MSS into two parts.

1.2 MSS moves laterally to open formwork,

Synchronization action is demanded for left and right formworks, centre distance difference between formworks at two side and piers should be not more than 5cm during the lateral moving process, symmetrically and synchronously moving.

1.3 MSS system moves longitudinally to cross piers

1.3.1 move laterally to the right position and check longitudinal moving device, then start movable scaffolding system longitudinal moving mechanism to make the complete machine move forward 30m;

1.3.2 if the complete machine is on the curved bridge, front and back support roller should be adjusted immediately in the moving process, so that the complete machine meets the demand of moving in a curve line.

1.4 MSS system moves laterally to close formwork, and the formwork is jacked to the right position

1.4.1 After the formwork moves longitudinally to the right position, check lateral moving device, start lateral moving cylinder to close formworks, it demands a synchronous action for lateral moving at two sides and that centre distance between left, right side and pier centre should be not more than 5cm

1.4.2 Close bottom die at two sides and formwork cross girder and formwork between main girders, adjust camber of side die and bottom die to meet related demands

1.4.3 Install pier top bulk formwork and check whether it is reliable or not.

1.4.4 Install rear anchoring beam and tighten pre-stress high tension precision rolling screw bar reinforcement, check contact condition between formwork template and poured girder body.

1.4.5 As supporting frame, firstly bind reinforcing steel bar, install pre-stress drill way, install inner formwork, pour girder body concrete, maintain and tension the pre-stressed girder

1.5 repeat above steps to construct the next span

2. Assembly and disassembly steps for support frame

As finishing installing one span of the bridge, the movable scaffolding system moves longitudinally to cross piers, as to install the next span, use crane to install support frame and movable platform on the front piers;

Transport removed movable platform and support frame to the piers at front of formworks, then install support frame and movable platform with cranes on the front piers