Lifting a 24te Pipe Bridge Over a Beck with a 250te Crane

Project

A 28m pipe bridge lifted across Alwent Beck

The brief

A new customer needed a 24te prefabricated pipe bridge, 28m long and 5m wide, lifted from its laydown area into its final elevated position across Alwent Beck.

The challenge

The bridge was long enough to distort if it was lifted from too few points, and the whole load had to pass over the beck. The crane pad also had to carry the crane’s ground bearing pressure.

How we did it

We lifted the bridge at 21m radius with a Grove GMK5250L 250te all-terrain crane, using a multi-point spreader beam arrangement to keep it stable. Before the main lift, an 80te crane on contract lift helped offload the bridge and assemble it at ground level.

The outcome

The pipe bridge was lifted and installed safely and without incident. On a long span like this the rigging matters as much as the crane, so the spreader beam arrangement was designed at planning stage to keep the bridge level and undistorted all the way through the lift.

3D view

Explore the lift in 3D

A model of the lift, built to the figures in our lift plan. Drag to spin it round and tap a number to see what each part of the job involved. Press Play the lift to watch it from laydown to landing, or Lift plan to see the key dimensions.

Illustrative model based on our lift plan.

Resources

Crane, rigging and ground

Crane

A Grove GMK5250L all-terrain crane rigged with 80te of counterweight and 42.3m of main boom, giving a capacity of 29.3te at 21m radius for the 24te bridge. An 80te crane handled the offloading and ground-level assembly beforehand.

Rigging

The 28m span called for an engineered spreader beam arrangement to share the load evenly and prevent distortion: a 16m long, 45te capacity top spreader beam with two 4.5m long, 19te capacity bottom spreader beams beneath it.

Ground and Matting

Plate tests had been carried out on the crane pad, and we revised our lift plan to bring the ground bearing pressure down to a level the pad could take.

Team

Our Appointed Person prepared the method statement, risk assessment and lift plan illustration for the main lift and for the smaller assembly lifts beforehand, and the work was carried out under experienced site supervision.

Grove GMK5250L

All-terrain
250 tonnes
70m main boom
21m jib

The Grove GMK5250L is a 250 tonne, five axle all-terrain crane with a 70m main boom, supplied with an operator for crane hire or as part of a contract lift.

View the crane

Timeline

From site visit to main lift

Safety

How we kept the lift safe

Our Appointed Person prepared the method statement, risk assessment and lift plan illustration, for the main lift and for the smaller assembly lifts before it.
Plate tests were carried out on the crane pad, and we revised the lift plan to bring the ground bearing pressure down to a level the pad could take.
An engineered spreader beam arrangement, a 16m, 45te top beam over two 4.5m, 19te bottom beams, shared the load and kept the bridge from distorting.
The work was carried out under experienced site supervision.

Planning notes

Lessons for long-span lifts

Design the rigging at planning stage. On a long span the rigging matters as much as the crane: the spreader arrangement is what keeps the load level and undistorted.
Test the ground before you settle the plan. Plate tests on the crane pad let us adjust the lift plan so the ground bearing pressure stayed within what the pad could take.
Plan the smaller lifts too. Offloading and assembling the bridge at ground level with a second crane had its own lift plan, before the main lift.

Gallery