Self-Healing Buildings: Smart Construction of the Future
“Self-healing building techniques are like how we depend on our skin when it heals itself after a cut,” said Mohamed Nagib AbouZeid (MSc ‘91), professor of construction engineering, on this innovative concept. One of AbouZeid’s lifelong interest is sustainable construction, to which he dedicated several research projects in collaboration with both undergraduate and graduate students.
A study that he has previously conducted several times and later supervised looks at the of use self-healing bacteria in minimizing cracks and ruptures in buildings. Working alongside his student, AbouZeid has made some interesting discoveries that he believes reveal a promising technique for future construction in Egypt.
Self-Healing, Safety and Sustainability
“If the material has the ability to heal itself, we prevent large cracks – and more importantly, the process itself shows us if something has been damaged,” AbouZeid said on the benefits of using bacteria in construction. While Egypt is not geographically prone to many natural disasters that create damages, there have been many incidents of construction failures, demolition of old structures and deterioration in the quality of buildings. For both faculty and students in construction engineering, the goal of preventing these occurrences and constructing ‘smart’ is one that will be taking over Egypt in the next few years.
The process began with an idea, AbouZeid recalled. “We went from putting some kind of material that breaks and leaks and fills the cracks, and then we heard of Dutch and French schools experimenting with bacteria, so we switched to that," he said. "We have the concept, we question the concept and we experiment with it.”
In an interdisciplinary fashion, AbouZeid and students collaborated with the Department of Biology, coming across bacteria called Bacillus Pseudofirmus. This specific type of bacteria is one that can endure under dire conditions, but also reacts with materials, such as concrete and limestone. “The bacteria feel the moisture in the air and react to it by forming a material that fills the crack with a white color," explained AbouZeid. "When we see this color, we know there must have been a crack here and is being dealt with."
This method can be extremely beneficial for construction in Egypt. “It’s definitely possible to implement here," AbouZeid attested. "It reduces repair costs and is safer." When it comes to adding quarters to existing buildings, such as extra rooms or floors, it may not be necessary, but is strategic for large-scale construction. “In structures like bridges over the Suez Canal, tunnels and huge water tanks, where water will leak and will cause damage, you want to relieve the load where you know it is prone to damage.”
While many students under AbouZeid’s supervision have examined the concept of self-healing construction over the years, their research has been hindered by the gap between academia and the market. “If it’s academics talking to academics, we won’t go very far," said AbouZeid.
AbouZeid hopes AUC's Technology Transfer Office, which facilitates the growth and development of new technology, can assist in that process and that their findings can make their way into Egypt’s massive upcoming construction project for the New Administrative Capital. “When political leadership talks about the New Administrative Capital, they say that they want the buildings to be smart," said AbouZeid. "One of those characteristics is for the buildings to have the ability to heal themselves."
Self-healing buildings are just one part of AbouZeid’s research interest. He is intensively immersed in promoting durability, recycling and safety in construction. “People are moving in a new direction for new buildings," he shared. "After a building has been in use, almost the entire structure can be reused. Constructors can take out the glass, the wood, the concrete, the aluminum and everything. Reconstructing it in another structure is a lot like Legos. This will save time and cost.”
Contributing to Engineering Research
AbouZeid is keen on supervising and nurturing his students' talent. He embraces research as a practice that encompasses multiple experiments, and more importantly, one that paves the road for future students at any level.
Other research projects he has been involved in revolve around the use of eco-friendly alternatives and methods in construction. One such project aimed to cut the use of non-friendly construction materials, such as Portland cement, which lessens the harmful effects of carbon dioxide emissions. Other projects involve making use of waste and recycled materials, refraining from the use of fresh water during construction, constructing with translucent materials to allow daylight to pass through designated parts of the building, reducing energy consumption and providing light and warmth.
AbouZeid praised AUC’s support of student research. University students have published in the American Concrete Institute Journal and were represented in the Canadian Society for Civil Engineers as publishers and conference attendees. At international events for engineers, he has encountered former students who now contribute substantially to the engineering field. “I am fortunate to be supervising a large number of undergraduate theses – those who gain recognition, not only from us at AUC, but through international publications and at conferences,” he said. “We are not a large University, but with our qualitative potential, I like to think of ourselves as pioneers in the field of advanced construction material and repair. I would like to acknowledge the University's support of graduate studies and research, as well as the undergraduate division, for the fact that they opened pools of funds and support. Not all universities do that.”