TEMPORARY SUPPORT equipment from shoring supplier MGF is helping main contractor Costain build a treatment plant at Barrow water treatment works near Bristol.
The project for Bristol Water lies close to treatment plant and services and involves excavation of a large pit for settlement tanks.
The pit is 25m long, 17m wide and nearly 6m deep so careful shoring was needed to provide a safe working environment and to prevent settlement damaging nearby structures, including a 1,500mm diameter gravity water main.
The final design comprised a cofferdam of Larssen LX8 sheet piles supported at two levels with MGF's hydraulic tank braces and struts. The top frame consists of a heavy duty tank brace with 15t power packs, mechanical Superstruts with 540kN Superstrut extensions acting as knee braces and cross struts.
The bottom frame is similar, but employs 30t power packs to counteract the greater lateral forces at the bottom of the excavation.
Work is due to finish in July.