Case Studies

HALFWAY BRIDGE SCOURS

Client – iGroup/Balfour Beatty

Value – £150,000

Duration – 4 weeks

Type – Scour Protection

PROJECT DETAIL:

The Halfway Bridge that carries the A272 Selham Road over a tributary of the River Rother, near Midhurst, had corroded and remedial action was required to maintain the safety and long-term durability of the structure.

Suttle Projects was contracted to install concrete canvas protection to the invert of the Armco structure, along with other minor maintenance works.

The structure was classified as a confined space, requiring operatives to have attained the relevant confined space training, and for breathing apparatus and gas monitors to be continuously present.

Whilst operatives were working on one culvert, a small sand bag dam was placed upstream of the structure to divert the flow through to the remaining culverts.  An eight-inch pump was utilised to over pump when required.

Loose material within the culvert was shovelled into wheel barrows and tipped into empty 1t bags.  Debris against the head walls was removed by using a 1.5t excavator.  Any remaining silt was jet washed away, working from upstream to downstream.

Grout was placed and smoothed into the crenulations of the culvert for the extent of the concrete canvas.  Any migrating of grout sediment was prevented by utilising a small silt curtain.

The concrete canvas was laid in position and stainless-steel tech screws were used to fix the canvas to the Armco material.  Areas where the culverts had corroded were re-painted and metals were brought back to clean steels throughout the structure.  The existing mortar was ground out and replaced with new mortar and brought back out to the existing level.

The work was completed on time and to budget.