Aarsleff Ground Engineering offer Slurry cut-off walls to prevent migration of groundwater, or polluted and contaminated materials present in the ground. Aarsleff has the specialist plant and labour to fulfil complex solutions complemented by years of expertise and experience designing and installing Slurry walls, also known as a cut-off slurry wall.
Aarsleff’s single-phase, self-hardening slurry trench cut-off walls are constructed by excavating a trench under a cement/bentonite slurry. The slurry remains fluid during excavation, and in this state allows the formation of a filter cake of bentonite on the side walls enabling the hydrostatic pressure of the slurry to prevent the collapse of the trench. Due to the cementitious content the slurry hardens within about 24 hours to form the low permeability barrier. The hardened slurry has a low permeability, typically 1×10-8 to 1×10-10 m/s and the strength properties of a stiff clay but it does not possess the plastic properties of clay.
Most slurry trench cut-off walls built in the UK are 0.6 m wide. The practical maximum width is 1.5 m, although a width of more than 1.0 m is unusual. In most ground conditions, trenches can be excavated to about 12-15m deep using hydraulic back-actors (backhoes). For depths below this, and in particularly difficult ground conditions, diaphragm wall grabs or cutters are used. Slurry walls are normally keyed into an aquiclude; an underlying layer of low permeability material.
Slurry cut-off walls offer the following advantages:
- Quick Installation
- Low-cost solution for low permeability barriers
- The use of high replacement CEMIII cementitious materials in the cement bentonite slurry mix design not only significantly reduces the carbon footprint of the mix but actually reduces the permeability of the cured material when compared to OPC.
For more information about Aarsleff Ground Engineering or to send in your enquiry, call 01636 611140 and speak to a member of our expert team today, or drop us an emailDownload Specialist Retaining Walls Brochure