How many times did you get angry or even worse, take your car to the garage for expensive repairs caused by potholes? The answer is most probably: too many times. The good news is that potholes could soon become a relic of the past due to futuristic plans to produce self-healing concrete.
The development of self- healing concrete is also aimed at improving the durability of structures and eliminating the endless traffic jams caused by manual repairs to structures. Structures made of self-healing concrete have an inherent healing mechanism that becomes active when a crack appears, thus rendering manual crack repair completely obsolete.
Scientists are experimenting with various groundbreaking new materials to find the ideal formula for to solve this issue.
|Self- healing concrete|
PU precursors have shown great potential
For the efficient healing of cracked concrete, the use of encapsulated PU-based precursors has already shown great potential. So far, results have shown a good regain in mechanical behavior and liquid-tightness. In proof-of-concept tests, glass tubes were used as encapsulation material.
However, to up-scale the technique and make it compatible with conventional concrete production and placing methods, polymeric spherical microcapsules would be more suitable. Therefore, research is ongoing to optimize the encapsulation technique. Moreover, PU-based precursors are adapted to increase the resistance of the healing agents to cyclic loading, so that also the healing of dynamic cracks can be considered.
Using sunlight to fix concrete cracks
Researchers have demonstrated a sunlight-induced, self-healing protective coating designed to fix cracks on the surface of concrete structures before they grow into larger ones that compromise structural integrity.
The new coating contains polymer microcapsules, filled with a solution that, when exposed to light, turns into a water-resistant solid. The idea is that damage to a coated concrete surface would cause the capsules to break open and release the solution, which then would fill the crack and solidify in sunlight.
Bacteria as healing agent
Also bacteria can be used as healing agent. Scientists are experimenting with the groundbreaking new material, which uses special bacteria to plug gaps and cracks opened up by bad weather.
Researchers at the University of Bath, Cardiff University and the University of Cambridge created the concrete blend, which is full of bacteria hidden in tiny capsules. As soon as water seeps into a crack, the bacteria quickly burst out their cases and produce limestone, sealing the gap up before it can widen and become a pothole.
Lower CO2 emissions and 50% lower costs
The scientists believe the technique could vastly increase the life of concrete, remove the need for repairs, and reduce costs by up to 50%.
Carbon dioxide levels in the atmosphere would be lower because there would be no need to constantly replace roads. More than 7% of the world’s CO2 emissions are due to cement production.