Dr. Timo Nijland
- Built cultural heritage
- natural stone
- buildig materials
The usual masonry material for exterior walls is brick, with some historic buildings built with natural stone. Mortar - a mixture of water, binder (cement, lime), fine sand and additives - holds the bricks together. The open pore structure of brick allows transport of moisture and salt solutions. TNO investigates modern and historic mortars and advises on measures to deal with damaged masonry.
The effective repair of historic masonry requires new restoration mortars to be compatible with historic material already present. TNO has the expertise to ascertain this compatibility, by determining the composition of the mortars in existing masonry and examining its microstructure, along with the nature of the damage. For specific projects and circumstances we assess the performance of mortars in the laboratory.
TNO is developing masonry desalination methods and various other techniques for preventing long-term damage. Two other current research themes are making masonry resistant to biodeterioration and the development of additives to enhance the salt-resistance of mortars.