Sainsbury’s Wombourne
During this contract, we had to erect a bi framed portal that was designed very slender sharing a spine beam in the valley.
Stresses imposed during erection would be far larger than any to be encountered when the building was complete. The stress on the spine beam meant both sides needed to be balanced during erection. Whilst the stress on the rafters would require the portal to remain on the hook to do this two cranes would be used at precisely the same time to release the load, hence balancing the stresses.
You will note the left hand crane positioned to the right hand side of its bay, the right hand crane to the left hand of its bay enabling each crane to lift into each other’s bay. Hence could assist from the opposing bay to lift in restraining steelwork. And vica verca by positioning the steel trailer centrally both cranes could pick from it.
Testimonials
This twin span portal frame was designed economically sharing the spine beam in the centre of the building.
Stresses imposed during erection would be greater than proposed load upon finished build. The stress on the spine beam needed to be balanced during erection. Whilst the stress on the rafters would require the portal to remain on the hook to do this two cranes would be used at precisely the same time to release the load, hence balancing the stresses.
You will note the left-hand crane positioned to the right-hand side of its bay and the right-hand crane positions to the left-hand side of its bay. This enabled both cranes to lift in each other’s proximity allowing opposite crane to assist in neutralising the stress for the other crane to erect hence balancing the stresses.
We finished this project a week ahead of schedule.
