3 Strange Innovations in Construction Materials

June 13, 2016 | Comments

The construction industry is a relatively conservative practice and the World Economic Forum wants to change this. It has recently released its first publication entitled Shaping the Future of Construction, wherein it intends to give an overview of the industry’s present state in terms of technology.

It also features some best practices and case studies of innovative approaches or solutions in today’s world—including a few weird ones.

 

Self-Healing Concrete

Scanning electron microscope image is of a sample of the self-healing mechanism in a slab of concrete that had effectively reformed itself after it experienced a crack. (Image courtesy of University of Cambridge.)
Scanning electron microscope image is of a sample of the self-healing mechanism in a slab of concrete that had effectively reformed itself after it experienced a crack. (Image courtesy of University of Cambridge.)

It might sound like something right out of a sci-fi movie, but teams of researchers at the universities in Cambridge, Cardiff and Bath have developed and are improving on a mixture of concrete that can self-heal when ruptured.

It works by using a set of micro-scale, self-repair mechanisms embedded in the concrete media. When a miniature crack occurs and breaks apart these capsules, a self-healing agent is released, repairing the crack before it gets any larger.

While these self-healing agents are effective for nano- and micro-scale cracks, more research will still need to be conducted for larger cracks. To achieve this, plans are in place to complement the microcapsules using spore-forming bacteria. These bacteria will feed on nutrients added to the cement, simultaneously facilitating calcite precipitation to plug the cracks in the concrete.

Integrating these capsules into the concrete is a challenge, as they need to be strong enough to survive the mixing process, yet delicate enough that they break apart during a rupture. If this integration were to be successful, however, it could have an enormous impact on the longevity of a material that is found in almost every piece of infrastructure.

 

Sweating Roofs for Green Cooling

The above image displays thermal testing of two different polymers that were considered for the hydrogel product. The polymer on the right was used for the patented technology as it facilitated faster cooling than the conventional polymer on the left. (Image courtesy of Wiley VCH.)
The above image displays thermal testing of two different polymers that were considered for the hydrogel product. The polymer on the right was used for the patented technology as it facilitated faster cooling than the conventional polymer on the left. (Image courtesy of Wiley VCH.)

Thermoresponsive hydrogel roof covering is essentially a technology that attempts to mimic the cooling effect of perspiration, but on buildings.

A team at the Swiss Federal Institute of Technology, ETH Zurich, estimates that this method of passive cooling could lower CO2 emissions produced by building air conditioners by at least 60 percent.

Essentially, the gel contains polymers that store rainwater on roofs for an extended period of time. After a rainfall, the sun heats up the gel, causing it to dispel water which evaporates, cooling the interior of the house through the release of latent energy.

The researchers compared the cooling effect of the hydrogel to a house with a bare roof. In both cases, the houses were air-conditioned to keep the internal temperature at 20 °C. The results of the study found that the house without the gel would emit 220 kg of CO2 per year if the electricity was generated by a gas-fired power station and the building with a hydrogel coated roof would emit just 80 kg of CO2 per year.

According to Wendelin Stark from the research team, plans have not been put in place yet to commercialize the technology. However, since these findings are already published, other companies are prevented from patenting it, meaning the technology is free to be implemented anywhere. If this method of applying hydrogel to a roof is being tried out, hopefully it will hold water.

 

Slippery, Liquid-Infused Porous Surface

The carnivorous nepenthes is the inspiration behind this design, as its slippery surface causes insects to fall into the plant.
The carnivorous nepenthes is the inspiration behind this design, as its slippery surface causes insects to fall into the plant.

An ultra-slippery surface can potentially be used for a number of applications “ranging from biomedical devices to architecture and fuel transport,” according to the Wyss Institute.

The new SLIPS technology, inspired by the nepenthes plant, is a combined porous medium with a lubricating film. The medium is capable of repelling a wide variety of substances from ice to crude oil under extreme temperatures and pressures.

According to researchers at the Wyss Institute, it can accomplish this under a low budget. SLIPS surfaces can be constructed from a broad range of simple, inexpensive materials without the need for specialized manufacturing facilities.

It is no coincidence that these technologies are all based on material science. The European Commission estimates that 70 percent of product innovation across all industries is derived from new or improved materials.

For more information, see the website of the World Economic Forum.

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