Conibase® Infrastructure Waterproofing and Protection

Pramod V. Patil, Product Manager (Waterproofing Systems), BASF India Ltd, Mumbai

BASF Construction Chemicals has developed a range of waterproofing, repair and protection systems utilising the latest cementitious, epoxy, polyurethane and composite technologies. Its Conibase® waterproofing systems have been developed to serve the needs of infrastructure builders and owners.

BASF India competence in terms of both refurbishment and new build applications is based on many years of experience gained across the world in a variety of climatic and service conditions. It has specified, manufactured and supplied over 5 million m² of performance waterproofing, surfacing, repair and protection products to an international list of Conibase® projects which include names such as: Bedford Lakes office development in the UK, Korushima/Akinada Bridge, Shimizu Omija Tunnel and Kuriyama Dam in Japan, MTR Rail tracks and MTR cut and cover tunnel in Hong Kong, Changi water reclamation plant and Resort World in Singapore, Simmering Power Station and Flemington Racecourse tunnel in Australia.

Choosing the Correct Solution

Infrastructures such as cut and cover tunnels elevated railways and water retaining structures are constantly exposed to aggressive chemicals found in ground water and from urban run-off; therefore it is essential to protect the exposed surfaces to prolong their lifespan. Specifying the correct solution for the waterproofing and protection of infrastructures is a complex decision, balancing current and future performance criteria against cost and installation time constraints. A well specified solution reduces whole-life cost and preserves the infrastructure to allow its long-term use. Conibase® helps to reduce this complexity with simple robust systems.

Company range of Conibase® systems can cope with the harshest environments from acidic ground waters, to seawater and where tunnels are installed by the push through method. The systems, which are applied by fast curing, spray application, can keep up with the most demanding construction schedule and have exceptional resistance to mechanical abrasion. Able to bridge minor cracks and compatible with cold jointing systems, Conibase® allows the structure to be fully waterproofed.

Areas of Application

While the tunnel is exposed, it is important to ensure that it is fully waterproofed before the overburden is returned. As the Conibase® can be sprayed over the cold joints and can cope with surface cracking; it suits itself to this style of application. The system requires a minimum of space to install reducing the need to have large excavations often needed for other systems. Combined with a range of priming systems suitable for application to newly cast concrete, it can enhance the construction schedule. The system must be able to accommodate movement and prevent the ingress of water and gases into the structure. The membrane must be of sufficient thickness, strength and integrity to bridge the cracks.

Basements

Basements and floors below ground are at risk from ingress of ground water or seepage after rain. This water ingress can create a long-term deleterious effect on the concrete and should be excluded. Creating a complete envelope to prevent the ingress of water can be easily achieved with Conibase® systems for both the floor and walls of the structure.

Water Handling Structures

Water is one of the planet’s most precious resources and much infrastructure is now being constructed to secure water supplies. The reduction of seepage from reservoirs, the building of water recycling and desalination plants provide many headaches for the designer. Conibase® has been used to line reservoirs to stop the loss of water in hydro electric plants, to waterproof the outside of water recycling plants to prevent ingress of the ground water and to line channels to prevent the super saturated salt solution discharge from contaminating the surrounding land. Conibase® can also be used for secondary containment by creating a waterproof and UV stable coating of bunds or retention ponds. Having high chemical resistance, it will give temporary protection allowing remedial action to take place.

Case Study

Conibase® can be used in most waterproofing applications and can be used in conjunction with other range of conipur systems to give a complete package for basements. It is also suitable for upgrading water retaining structures to prevent the ingress of potential pollutants. One such project where this system has been used is Changi Water Works in Singapore and the built up of the systems consists of a Primer layer, Broadcast sand, Membrane layer (sprayable PU membrane) and a Topcoat (for UV resistance).

Changi Water Works in Pictures