1Delft University of Technology, Faculty of Civil Engineering and GeoSciences, Department of
Materials & Environment, Stevinweg 1, NL-2628 CN Delft, the Netherlands
In 2006 a research program was launched at Delft University of Technology aiming for the development of a new class of materials, i.e. materials with an inbuilt healing mechanism. The idea is that these novel materials can selfrepair damage resulting in substantially decreased maintenance and repair costs and increased service life. Several research projects focus on cement-based materials such as concrete and asphalt. One project that will be discussed here concerns bacterial-based concrete. The bacteria, which are added to the concrete mixture in form of encapsulated particles, are able to produce calcium carbonatebased minerals, a process that results in sealing and water tightening of cracks. These and more examples show that novel materials and constructions which are designed to control damage rather than prevent damage by featuring an inbuilt healing mechanism could be more economical than traditional ones.