In terms of advancements in concrete technology the driving forces have been durability and speed of construction. However the environmental impact of construction materials is becoming an increasingly important driver. In this paper Mehta evaluates concrete technologies using the criteria of construction speed durability and environmental impact. One of the technologies he examines is high volume fly ash and slag concrete particularly in terms of their use in structural concretes roller compacted concrete dams concrete pavement for highways and base courses and embankments.
Technical Report Author: P. K. Mehta
Based on a review of existing information the team examined the technical environmental and economic benefits and costs of using naturally pozzolanic materials from provincial deposits as compared with those associated with the use of fly ash from coal-fired thermal electrical power plants as a supplementary cementing material in British Columbia. Based on their findings the team concludes that there is no indication that the natural pozzolans from any of the identified sources in British Columbia have any apparent technical advantage relative to the fly ashes being imported into the province and used as portland cement replacement materials. Further in terms of the present supplementary cementing materials market in British Columbia there would be no environmental benefit derived from using a natural pozzolan instead of fly ash. Finally the delivered cost of a natural pozzolan suitable for use as a supplementary cementing material will be of the same order of magnitude but possibly higher than the price of fly ash in the Greater Vancouver Area market.
Consequently it is recommended that no further investigation of this issue be carried out by the EcoSmartâ„¢ Concrete Project until it can be demonstrated that there is a demand for portland cement replacement materials in the province that cannot be satisfied by the importation of fly ash form Washington State and/or Alberta at an acceptable cost.
Technical Report Author: Robert Gray, Ph.D., P.Eng., James Atwater, P.Eng., W. Dunbar, Ph.D., P.Eng., CMP Technologies Ltd.,
Fast and Epp s investigative report reviews the potential use of high volume fly ash concrete in high rise construction in a way that introduces no cost premiums to the existing construction process. The report concludes that an hvfa mix that is transparent in terms of set times and cure rates is not practical at this time and that the best opportunity for HVFA usage lies in the podium and parkade areas of typical highrise buildings.
Case Study Report Author: Robert Schmidt, P.Eng., Paul Fast, P.Eng., Fast + Epp,