Resilient Foundations: Building In Repair Capability

There is considerable literature on strategies for the repair and self-healing of concrete structures. However, in geotechnical engineering there has been much less interest in the repair of foundation elements. Typical remediation strategies involve provision of extra piles or further ground improvement. One of the approaches which is seen as promising in concrete repair is the use of bio-cements. These are solutions where bacterial actions result in the precipitation of a chemical that can act as a cementing agent. The most widely investigated of these is the use of ureolytic bacteria to precipitate calcium carbonate.

The paper provides a review of repair strategies and techniques used in concrete to encourage self-healing should damage occur. It describes the MICP process, and presents data showing how bio-cement can improve the strength and stiffness of sandy soils. Finally the paper reports results from some preliminary laboratory model tests performed to investigate the ability of bio-cement to repair cemented soil columns.