Grout injection to waterproof concrete is probably the most widely used application of injection in the construction industry, particularly in tunnelling.
Tempo-PCE has acquired a wide range of experience with concrete injection, both in the UK & Qatar, working on new structures, tunnels, spray concrete systems, expansion joints, and secant piles.
Applications for concrete waterproofing injection range from sealing eyes using an acrylic tube system, to segment sealing using polyurethane (PU). Different materials are used depending on flexibility requirements and location. Usually, these materials are single shot and can be injected using small 110-volt electric pumps and are easily portable.
Tempo-PCE is also experienced in injecting into existing structures – usually hard-to-access, sensitive areas, for instance service trays or backfill above a steel soffit. Waterproofing injection avoids the need to disrupt the cables and pipes, and can link with existing waterproofing in the road deck.
A knowledgable use of medium to high pressure injection can allow work from underneath the soffit, with the structure remaining in full use – offering a low impact alternative to conventional methods of repair. For example, in most cases, traffic management is unnecessary.
The two types of waterproofing material used by Tempo-PCE are PU and acrylic resin. The acrylic resin has a very low viscosity, meaning it penetrates the finest concrete cracks. It can also fill voids and envelop service pipes, some have a anti corrosion inhibitor. The resin remains in fluid form indefinitely until a chemical catalyst is used to make it set. PUs use either catalyst or the water within the structure to set.
- Waterproofs backfill
- Flexible or stiff
- Setting time totally controllable
- Can work in conjunction with water management, e.g. weep holes
- Can use high or low pressure, site dependant
- Good chemical resistance against road salts Rust inhibitor
- Retains appearance of existing structure
- All quantities can be measured and recorded
- All work from below or above the soffit
Typical Applications: Bridges, Tunnels, Retaining walls, Steel piles for cutting out
Related information & Products
- Can be used to stabilise the ground behind piling to create space for tunnel boring machines
- Can used as a concrete or cast-iron waterproofing system
- Acrylics Resin > TamAcryl 2000
- Polyurethane > TamPur 130/ TamPur 150
Health & Safety / Environmental
- Potable water certified
- No special PPE required
- No specfic storage or containment required
Application Conditions & Limitations
- The acrylic resins have permanent open times until an accelerator is added, giving maximum flexibility.
- Polyurethane is injected at the same time as the catalyst, and will set in minutes, depending on the amount of catalyst added or the volume of water present
- All the acrylic and polyurethanes are affected by low temperatures, which slow down the reaction time.
Previous Site Environments
- Confined space
- Over a water course with EA approval
- Working from rafts moored under a bridge
- Tunnel under a working road
- Variety of road bridges from below
- Unrestricted traffic
- Flexible to semi-flexible
- Working beneath a road bridge over rail tracks
- Demark Road Tunnel, Nomenca
- Bishops Ave – Harrison Varma
- White Street – Dyer & Butler
- CrossRail: BFK, Bond St, TCR & Fisher St
- CrossRail: DSJV, Canning Town, Stepney
- Qatar Doha: Qatar Rail, Gold Line, Red Line South & North