Waterproofing materials are a critical component of building construction, protecting structures against water damage and mold growth. Recent innovations in waterproofing technologies are helping to make these systems more effective and long-lasting.
One such innovation is a coating developed by scientists at Swansea University that is nontoxic and economical. This spray-on material could be used to coat a wide variety of surfaces.
Active Water Management Systems
Waterproofing systems protect concrete and other surfaces against moisture infiltration, protecting structural components and finishes from damage. They can also prevent the ingress of corrosive soil and frost. Positive side waterproofing systems can be applied as a liquid membrane or as a built-up or laminate membrane. They can be used alone or in conjunction with other waterproofing systems to meet specific project needs.
Liquid membranes are spray-applied and are typically made from thermoplastic or rubber elastomers or bitumen or epoxy-modified materials. Spray applied membranes can be cured at room temperature or heated, depending on the type of system. These systems are highly sensitive to major temperature fluctuations during curing, so proper installation is critical.
When a spray applied membrane is installed as part of a fully bonded waterproofing system, it can be embedded between two concrete linings. This can increase the watertightness of the primary and secondary linings, which are usually not watertight due to geometry, shear connection or surface roughness.
Morgan Tunnelling was contracted by national grid plc to build a power cable tunnel in SE England. The tunnels were lined with a combination of primary and secondary sprayed concrete linings. The waterproofing system had to form a strong bond with both the primary and secondary sprayed concrete linings as well as with the final cast in-place concrete lining. After extensive testing and evaluation, they chose Stirling Lloyd’s Integritank HF spray-applied methacrylate membrane system to waterproof the front and back shunts of the cable tunnel.
Advanced Coating Systems
The use of advanced coating systems can improve the performance, durability, and functionality of a wide range of materials. These innovative systems can provide improved resistance to wear, corrosion, and other forms of damage, as well as enhancing other properties, such as hardness or electrical conductivity.
There are a variety of ways to apply advanced coatings, including dip coating, chemical vapor deposition (CVD), and plasma spraying. These coating processes allow for the creation of highly specialized and complex coatings with custom designs and specifications.
Other areas of research include the development of smart coatings, which can change their properties in response to environmental changes. For example, a coating that is sensitive to temperature changes may be able to warn users when the surface is too hot. Additionally, researchers are using biomimicry to create coatings that mimic the self-cleaning surfaces of plants and animals.
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Nanotechnology
Nanotechnology is a rapidly growing field that explores the properties of particles at sizes between 1-100 nanometers. Particles at this scale exhibit unique physical and chemical characteristics, which can be manipulated to produce new materials with superior properties. This technology is currently being used to improve building materials, including plaster, by increasing their resistance to water and preventing damage from other sources.
Using nanotechnology, researchers have developed a waterproof coating for plaster that can be applied via spray application. This coating is able to create a seamless bond that is impenetrable by liquids. It also protects the substrate from dirt, corrosion and decay.
This new coating is inspired by the qualities of lotus plants, which are able to grow in muddy environments because their leaves are waterproof and self-cleaning. The waterproofing coating is composed of bentonite clay particles that can expand to 15 times their original volume when submerged in water. The material also has a self-healing ability and can be repaired after cracking or puncturing.
Nano waterproofing can be applied to all types of surfaces, including brick, concrete blocks, cement sheets, mortar, sand stone, and plaster. This coating can reduce the permeability of these materials by up to 99 percent, and it has been tested under harsh weathering cycles. The coatings can even prevent the deterioration of wood structures by preventing the growth of mould and fungus.
Self-Healing Coatings
Waterproofing materials have come a long way in the last thirty years, especially in the construction industry. Some of the biggest innovations have been in waterproofing membranes, which create a seamless barrier to protect structures from water intrusion and damage. Many of these materials use nanotechnology to make them stronger and more resistant to cracking or peeling. Other innovations include self-healing coatings that automatically repair minor damage to maintain their waterproofing properties.
Self-healing coatings are able to repair surface scratches and mesoscopic damage, such as microcracks and cavitation, to prevent further degradation. These coatings can also heal multiple times in the same area, reducing life cycle costs by preventing the need for repairs or replacement. They are also able to reduce corrosion in metals by sealing micro-cracks and pores, which can otherwise allow corrosive liquids into a structure.
Researchers at Nanex are currently working on a new type of self-healing coating that draws inspiration from nature to achieve its functionality. The coating mimics the water-repellent and self-cleaning surfaces of lotus leaves, which are able to stay dirt-free in muddy, semi-aquatic environments. When water drops on a lotus leaf, they beads into nearly perfect spheres and roll off the leaf, picking up and carrying away any dirt and debris along the way. The same technology is being used to develop a protective coating for metallic structures that can automatically heal itself when it gets scratched or damaged.