Wastewater - Filter Bed Containment, Clay Mills
Clay Mills in Burton-on-Trent, Staffordshire is the largest filter works in the Midlands, serving a trade load and domestic population equivalent to c.400,000. As part of a programme of refurbishments to the facility, movement and dummy joints in the water treatment beds were identified as damaged, failing and leaking to ground.
Engineering consultant MWH, working on behalf of Severn Trent Water, approached Adler & Allan to inspect the site and propose an effective solution that would repair the damage and ensure containment of the water treatment within the existing concrete works. Due to the water treatment beds covering an area the equivalent of 5 football pitches, the solution needed to work without spray lining the entire area or replacing the concrete structure.
MWH initially offered 10m demo sections to Adler & Allan and one other contractor, and after a period of successful testing, the major water company awarded the complete works to Adler & Allan.
Incorporating its innovative, patented technologies and experience of completing remedial concrete works, Adler & Allan developed and designed a solution to replace damaged areas and reinstate watertight integrity to the structure. Taking into account the need for movement and the limitations of aged concrete, Adler & Allan’s solution included the use of Adalline 400, its proprietary Polyurea spray coating.
Adalline 400 offers unique flexibility, is water and chemical resistant and adds structural integrity to many materials. In addition, it is quick to apply and dry, and environmentally friendly, with no VOCs.
The damaged soft joints were removed before a high-pressure water system was used to expel all previous sealant, contamination and surface laitance. The area was then dried thoroughly. Joints were filled with backing rod, and a 5mm recess was cut parallel to and either side of the joint. A quick setting primer was applied along with a fine grit to enhance bonding adhesion. Liquid soft joint was then applied before using Adler & Allan’s Adalline 400 Polyurea spray coating over the joint. Unlike epoxy or resin liners, Adalline 400 has in excess of 300% elasticity and flexes with the joint movements between the concrete.
Adler & Allan successfully delivered the project on time and within budget. In a 4-month period, over 2000m of movement joint and over 2000m of dummy crack repairs were completed with Adalline 400 Polyurea overbanding. Severn Trent Water was able to replace bays of stone as work progressed and without any breaks in the project schedule, A&A were able to deliver a fast return to service.
In addition to reinstating immediate watertight integrity, Adler & Allan provided a unique 50 year guarantee for the works. Due to the technological capabilities of the A&A solution, no other company was able to offer a guarantee of this duration for such a solution.
A&A’s innovative solution cost significantly less than lining the entire area or complete removal and replacement of the concrete structure, without compromising its efficacy.