Used for construction of pumping stations, wet wells and manholes, particularly in difficult ground conditions, adopted when the depth of water is high and the foundations are to be laid under water.

• Suited to weak soils, high-plasticity clays, silts, sands and gravel
• Suitable for jacking pits

Marshalls Civils & Drainage offer a range of reinforced precast concrete manhole chambers specially designed for sinking by the caisson method from 2000 mm diameter to 4000 mm internal diameter in varying depth.

The caisson chamber shaft sinking system was originally designed for use in micro-tunnelling, but is now more widely used for construction of pumping stations, wet wells and manholes, particularly in difficult ground conditions, adopted when adopted when the depth of water is high and the foundations are to be laid under water. The caisson method is achieved by using a shaft sinking plate system and is manufactured in accordance to BS EN 1917:2002 and kite marked where relevant to BS 5911-3:2010.

Features and benefits:

• Suited to weak soils, high-plasticility clays, silts, sands and gravel.
• Minimal site labour costs as delivered ready to install.
• Immediate permanent shafts as the caissons are constructed off-site enabling quick and easy installation.
• Suitable for jacking pits where a hole is dug in preparation for the installation of a tunnel or casing for the machinery to fit into.