Methods for evaluating the reactivity of supplementary cementitious materials (SCMs) for use in concrete

The use of pozzolans as a supplementary cementing material (SCM) to partially replace Portland cement in concrete is well established and can lead to many benefits including improved durability and a lower carbon footprint. The concrete industry needs to find alternative sources of pozzolans to replace fly ash and slag; among the most promising alternatives are natural pozzolans, ground glass and ash “harvested” from landfill sites where fly ash has been dumped for decades. The term “natural pozzolans” covers a very broad range of materials from raw deposits of volcanic ash, pumice and trass (to name a few) to calcined clays and shales; the impact of these materials on the performance of concrete varies widely. Unfortunately, existing standardized tests in the cementitious materials standards (e.g. CSA A3000) are not capable of reliably determining the suitability of pozzolans for use in concrete, and their use can often result in acceptance of unsuitable inert materials with little to no pozzolanic properties. A number of new tests and modifications to existing tests have been proposed but research is required to determine which of these tests are the most reliable and what acceptance limits would be appropriate.

Faculty Supervisor:

Arezki Tagnit-Hamou;Michael Thomas

Student:

Partner:

CSA Group

Discipline:

Engineering

Sector:

Construction and infrastructure; Professional, scientific and technical services

University:

Université de Sherbrooke; University of New Brunswick

Program: