EPFL scientists have developed a new approach to stabilizing clay soils.
EPFL scientists have developed a new approach to stabilizing clay soils. The method involves using a battery-like system to apply electric current to carbonate and calcium ions in order to promote soil consolidation. Their findings were published yesterday in Scientific Reports.
According to figures released by the UN yesterday, natural disasters have killed more than 1.2 million people since 2000 and cost nearly $ 3 trillion.These pressing threats bring into sharp focus the need for new answers to the problem of soil stabilization. Scientists at EPFL’s Laboratory of Soil Mechanics (LMS) have developed a number of sustainable solutions, including one that uses enzyme metabolism. Although these methods work for a wide range of soil types, they are considerably less effective when it comes to clay soils. In a paper published yesterday in Scientific Reports, the team demonstrates how chemical reactions can be enhanced by using a battery-like system to apply electric current.
A new type of biocement – produced in situ and at ambient temperature – has recently been put forth as a promising method for stabilizing various soil types. The method harnesses bacterial metabolism to produce calcite crystals that durably bond soil particles together. This biogeochemical process is energy-efficient and cost-effective, and could be rolled out quickly in the coming years. But since the ground needs to be impregnated for the method to work, it is less suited to low-permeability clay soils. Now, the LMS team has developed and successfully tested a viable alternative, which involves applying electric current using sunken electrodes. “Our findings show that this geoelectrochemical system does indeed influence key stages of the calcification process, especially the formation and growth of the crystals that bind the soil together and enhance its behavior,” says Dimitrios Terzis, a scientist at LMS and one of the co-authors of the paper.
Read more at Ecole Polytechnique Fédérale de Lausanne
