Costain is supporting the development of self-healing concrete by carrying out trials on one of its live highway projects in Wales.
As one of the main industrial partners of the Engineering and Physical Sciences Research Council (EPSRC)-funded Materials 4 Life research project, Costain has been sponsoring research by Cardiff, Cambridge and Bath Universities into such materials. The aim is to improve the durability of concrete structures.
Self-healing concrete uses a combination of shape memory polymers, microcapsules and microbial healing to reduce or slow down the effects of deterioration due to ageing or damage.
The importance of the research, the progress of which Costain civil engineer Oliver Teall (pictured) presented at the 5th International Conference on self-healing materials at Duke University in Durham, North Carolina, this summer, can be seen in the identity of some of its backers, with Highways England and the Welsh Government among those interested in the outcomes of the project.
“We are the only major research group in the UK investigating this, and have been recognised by the international community as a key global player,” said Teall. “We’re planning to start construction of a trial structure in August on the Heads of the Valleys highways improvement project in South Wales.
“This will give the research team an opportunity to monitor the performance of the material in a real site-based environment and is a key element of the research.
“We’ll be building a full-scale wall structure with a number of concrete panels. Into each panel we will incorporate different combinations of self-healing techniques. These will be loaded to artificially damage them, and then monitored to see how they react and recover over time.
“We plan to start testing at the end of September, running for a minimum of six months. From this trial we should gain an insight into the feasibility of constructing a full-scale structure with these techniques and their early-stage effects on structural properties.
“We’ll be looking at the effect of the healing techniques on areas such as stiffness, permeability and the mechanical damage recovery of the trial panels.”
Oliver is currently on secondment to Cardiff University where he is completing a PhD as part of the project. His role includes the coordination of the site tests of the material and developing the shape memory polymer system.
