Concrete has served the mankind well, as world's premier construction material, over the past 150 years. Nonetheless, it is arguable whether concrete has kept pace in developing with time. For example, until the beginning of this century, there has not been a significant movement towards the adoption, in standards for specifying concrete, of composite cements using additions (cement combinations) and recycled and secondary aggregates (including construction demolition) in structural concrete.
Likewise, although the method of specifying concrete has changed, with specific deterioration mechanisms (durability) assigned to exposure classes, current specifications, by and large, still revolve around the citadels of limiting factors namely, minimum compressive strength, water/cement ratio and minimum cement content, which have been allowed to have a stronghold in specifying concrete.
In delivering this presentation, and drawing from his life-time research undertaken at the University of Dundee, in collaboration the U.K. government and construction industry, Professor Dhir takes the view that the citadels of concrete specification inhibit innovation and are in danger of hindering the much required progress of concrete as the world's premier construction material.
He argues strongly a case for breaking out of this straitjacket and instead adopting a responsible shift towards performance-based approach to concrete design and construction.
This will allow the much needed flexibility in concrete design and enable concrete to respond to the demands of changing world, such as,
- Climate change,
- Carbon footprint,
- Economic pressures,
- Client pressures,
- Increasing demands from building insurance and
- High performance concrete requirements
The question is.... Are we ready for adopting this radical change?
Professor Dhir stresses that in order to seize this opportunity and to ensure that concrete emerges as the sustainable solution and continues to serve construction world over, will require a well focused, coordinated and visionary approach across all communities within the concrete construction sector.
Professor Dhir believes that higher education institutions have a vital role to play in meeting this challenge.