The project comprised the design and construction of necessary strengthening works to the existing Stonebridge across the River Skeme in Darlington. In order to ensure that the bridge remained a feasible heavy live load access and egress point to the town centre.
Following a client led feasibility survey the existing bridge failed the assessment capacity. Darlington Borough Council explored various options for the restoration of the bridge in order for the bridge to active and carry full HA live loads, such as buses and delivery wagons in and out of the town centre.
Originally the clients preferred option comprised undertaking necessary strengthening works to the existing central span and footways to provide the required capacity and subsequently carrying out maintenance painting to the remainder of the structure in order to remediate all defects.
Phase 1 consisted of the replacement of the existing central span steel work with precast concrete beams with permanent formwork supporting an insitu concrete deck allowing for the reduced loadings on the existing piers and also avoided the need for future maintenance painting to be undertaken on this section of the bridge.
Further works comprised of the removal and replacement of the outer concrete decks along with the reconstruction of the footpaths and service supports using lightweight concrete, which were subsequently waterproofed and resurfaced ready for the reopening to traffic.
Phase 2 of the scheme consisted of carrying out maintenance painting of the existing parapets and remaining steel supports, plus the necessary replacement of stone pilasters.
This work required an encapsulated scaffold to be hung down from the bridge with ladder beams for the creation and fitting of a working platform enabling blasting and painting works to be carried out.
The works were carried out in three sections by sandbagging off the working area with the river diverted into the remaining two spans.
A pedestrian walkway was maintained throughout the duration of the works. This was created through the use of pedestrian water filled barriers. Our compound was located next to the river and deliveries were banked in and out. We also had the facility to use the bus lane if needed and we liaised closely with Arriva and the Council if this was required.
The deck reconstruction works were programmed to be carried out in two halves, and during the works the bridge remained open to traffic exiting the town centre, with inbound traffic using a small detour into the shopping areas. Two overnight closures were arranged to allow installation for the PC beams, to avoid disruption to buses. This worked very successfully with minimal disruption to buses and other traffic and the works were received very well from all parties involved.
Gap year placement student Mark Knighten worked on the site as Site Engineer allowing him to gain valuable experience.
Two Darlington schools are participating in our Building My Skills programme which provides students with a rounded introduction to the world of work through regular, timetabled business engagement sessions as part of the curriculum. We also completed a stay safe campaign at Redhall Primary School which highlights the dangers of construction sites and provide guidance on how to avoid them.