THE PROCESS - ERECT FRAME
The process of erecting the aluminum sub-structure (frame). This process begins with the erection of the first arch. While still on the ground, nylon and wire ropes are attached to this first arch in specific locations. These guy off ropes will support the first arch. Erect the arch using the crane. It is recommended that only nylon straps should be used for this operation to avoid damage to the aluminum arch, but the discretion lies with the company providing the crane. Position the base of the arch into its proper location and anchor. Tighten the guy off ropes. Put a little slack into the rigging and, using the guy off ropes, plumb the arch.
On very large structures (100' wide and larger), it may be convenient to use a optical transit. Once the arch is plumb, disconnect the rigging and prepare to raise the second arch. The second arch is raised into position approximately 10' from the first arch. This arch is erected with a few spreaders (purlins) which were attached while the arch was still on the ground. These spreaders are then connected to the first arch. Temporarily anchor the arch. Move on to the next arch. Each arch is erected in the same manner.
above: cut-away view of concrete pad and beam
Typical equipment required:
- Electric power
- Crane c/w rigger
- 2 Manlifts
Specific equipment information
