Waterproofing Membranes for firmer structures

Effective treatment and repair of stations increases life of waterproofing system thereby extending its durability.

Waterproofing technology is continuously progressing. Several concepts have been illustrated that are useful for technology planners and forecasters in the field. The concept of liquid waterproofing has existed since centuries when natural bitumen was combined with jute, straw, rag felt and other man-made materials to provide a waterproofing solution.

Gained popularity
Waterproofing with liquid membranes has gained popularity due to ease of application or user- friendly, it is a fully bonded system, thus ensures greater security against infiltration or damages to liquid membrane, system is seamless, i.e. without joints, they can be installed easily on any contour surface, according to Hasan Rizvi, Sr. Vice President, STP Ltd.

The liquid membranes (bitumen, resin, acrylic, polyurethane, water or solvent based, in one or two-components) can be used in civil, industrial projects. Main application is waterproofing of roofs, balconies, terraces, roof-gardens and planter’s tubs, walls, parking lots and concrete structures, but also they can be used to waterproof surfaces and concrete walls, against-ground water.

Two-components cementitious elastomeric liquid applied waterproofing membrane: ShaliCem EWP of STP Ltd can be reinforced with glass fibers and is used for waterproofing roof, sunken, watertank, swimming pools, foundations, retaining walls etc.
Liquid polyurethane materials: ShaliUrethane LHM and ShaliUrethane BTD, can be used for all types of waterproofing, applied by roller or airless spray to waterproof balconies, roof deck, mechanical equipment rooms, wet rooms, terraces garden system etc.
Liquid applied TarFelt LM material: This category of product is very versatile because they allow repairing old Tarfelt waterproofing solutions without dismantling the existing system.

Evaluation and repair of concrete structures
Waterproofing systems and repairing is the serious issue and it always damages the basic concrete structures like high-rise building, malls and metro stations. It is always seen that specifically government departments are not focussing on these serious issue of water leakages from concrete structures and never treating and repairing with technical and expert agencies. Few specialised products and procedures, specifications are there in the industries which are cent per cent results oriented on leakages issue and offering guarantee for 20-25 years, says Krishna Mestry, Director, K R Waterproofings & Polymers.

According to Mestry, it is always better to check the structural condition and the application system and products properly. Specifically, for metros and railways, roof treatments should be taken care properly with high quality products, need to treat all expansion joint properly with specialised sealant like poly urethane based or waterproofing membrane which as specially designed for waterproofing and expansion treatment like combiflex etc. Always protect the any waterproofing systems and treatment with proper protective layer like for under roof with cement mortar screed or and any specialised protective membrane or coatings. For open to sunlight, always use UV resisting protective membrane or coatings. Use advance developed products like poly urethane-based product, epoxy-based products or some liquid membrane and coatings which are giving 100 per cent results with durability of the system.

Everlasting solutions to waterproofing problems
Tremco provides exceptional solutions for waterproofing underground structures. A combination of Polyurethane Injections to stop active leakages through sheet pile walls and use of our dual waterproofing membranes from the paraseal range, ensure an everlasting solution to waterproofing problems, says Sunny Surlaker, Head Technical Communication and Marketing, Tremco India Pvt Ltd. Paraseal SW is a sheet waterproofing membrane consisting of 0.375mm of HDPE and a layer of expandable granular bentonite. The system is resistant to being submerged in saline conditions. The nature of the Paraseal dual waterproofing system allows for installation over green or damp surfaces accelerating the construction process. The bentonite can expand up to eight times its original thickness to stop water that may make it past the HDPE layer, providing a second layer of protection.

The company also supplement the paraseal range with a range of crystalline waterproofing additives and coatings. One-part, cold fluid-applied elastomeric modified polyurethane waterproofing membrane TREMproof 250GC is a rapid-curing, high solids, VOC-compliant material that can be applied to damp or green concrete. TREMproof 250GC can be applied in as little as 24 hours following the removal of concrete forms. It can also be applied to damp concrete, reducing the delays associated with rain or other sources of moisture. These can be used in station buildings, cut-and-cover tunnels, as well as joint treatment in elevated rail sections.

Our urethane sealants based on Tremco’s unique moisture triggered chemistry have extremely high adhesion, chemical resistance and very high movement accommodation factors, which make easy work of treating both construction as well as moving expansion joints. We also provide abrasion resistant waterproofing systems for Pedestrian, says Surlaker.

Offerings
For metro stations and railways, need to treat and repair the waterproofing system with poly urethane based waterproofing products and systems with protective coating which increases the life of waterproofing system and extend its durability. Further, helps in protecting the main structures and leakages free from water.

For metro station, need to coat all pillars and girders and main concrete structures of the metros with waterproofing coatings or with liquid waterproofing membranes, specifically need to coat or paint the entire concrete structures with epoxy or poly urethane based coating which are giving long last protection to the structures.

Cities like Mumbai, lot of air pollution and industrial pollution, need to be taken care of these mass public transport systems with extreme care so that metros and railways can serve us in a better way.

Few revolutionary products
TREMproof 250GC: A hybrid PU coating based on moisture-triggered chemistry that can be applied to green (freshly de-shuttered) concrete or damp concrete.
Vulkem Range: Trafficable waterpro ofing systems for podiums, terraces and car parking structures
Dymonic 100: A highly versatile, hybrid sealant that has a movement factor of -50 or +100, and can be applied to green concrete or damp concrete.
AlphaGuard MT: Moisture triggered Hybrid PU Coating for roofs that can provide over 25 years of life in addition to heat reduction for cool roofs.
Firestopping: Innovative gunnable and paintable acrylic and silicone fire-stopping sealants to treat penetrations against fire. One of the grades in this range is also in tumescent.
Heavy duty pavement and runway sealants: Jet fuel, abrasion and UV resistant sealants for heavy duty pavements and airport runways. The company is looking to launch a further line of products incorporating Tremco’s patented PUMA technology that brings together all the advantages of Methyl Methacrylate, with the flexibility, ease of use and eco-friendly benefits of PU coatings. The focus on new technology will be the key to furthering the technology available waterproofing segment to new frontiers, says Surlaker.

Waterproofing with liquid membranes has gained popularity due to ease of application or user- friendly, it is a fully bonded system.
Hasan Rizvi, Sr. Vice President, STP Ltd

For metros and railways, roof treatments should be taken care properly with high-quality products.
Krishna Mestry, Director, K R Waterproofings & Polymers

The focus on new technology will be the key to furthering the technology available waterproofing segment to new frontiers.
Sunny Surlaker, Head Technical Communication and Marketing, Tremco India Pvt Ltd

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