Groundforce Shorco has supplied its recently developed Modular Maxi Brace hydraulic shoring system to support a large excavation for construction of a major surface water attenuation system near Rotherham.
The company, which specialises in excavation support systems and piling equipment, was awarded the £22,000 contract by main contractor Admiral Construction Ltd.
Brookfields Park is an 85 acre, major new mixed-use scheme being developed by regeneration specialists St Paul’s Developments. The £200 million project – an important contribution to the regeneration of this part of South Yorkshire – comprises industrial, warehousing and office buildings totalling 1.2M sq ft.
The huge attenuation system comprises large underground tanks to collect water, allow settlement and control discharge to local water courses.
The excavation is 107m long x 6.7m wide x 4.5m deep and is supported by Larssen 603 steel sheet piles and Modular Maxi Brace waling beams in conjunction with 50tonne capacity MSK mechanical struts from Groundforce Shorco. The 6.0m long Larssen piles are driven to full depth providing a 1.5m toe-in below excavation formation.
This so-called ‘propped-cantilever’ design means that only a single support frame is required to shore up the sides of the excavation. The high bending capacity of the modular maxi waling beam resulted in cross strutting being only required at 9m centres, thus providing excellent working room for construction of the attenuation tank.
High load capacity Mega Brace frames were used to create even larger 14.2m clear openings at either end of the excavation, to allow three 1.5m diameter plastic pipes to be fed into the excavation.
Installation of the shoring system was progressive and rapid, thanks to the use of Groundforce Shorco’s new modular Maxi Brace and mechanical cross strutting. The Maxi Brace’s simple pinned connections make it quick to install and enables it to be used in irregularly-shaped excavations.
Steve Savage, Contracts Director at Admiral Construction said. “We chose to use Groundforce Shorco’s Modular Maxi Brace system because of their pro-active response to a challenging temporary support scheme. The works were very close to a major road so it was essential to adopt a system of shoring that provided a flexible design offering ease of installation in conjunction with the excavation works.”
