Knowledge CentreTechnical Resources SearchConference PapersPavement preservation through the use of long‐life concrete pavements while also lowering carbon footprint: Quebec Case Study

Pavement preservation through the use of long‐life concrete pavements while also lowering carbon footprint: Quebec Case Study


Contempra, also known as GUL according to CSA Standards, is manufactured in Canada by intergrinding regular cement clinker with up to 15% limestone. From an environmental point of view, successful implementation of Contempra cement across Canada would decrease CO2 emissions by 10% while still producing concrete with the same level of strength and durability as concrete produced with regular Portland cement (GU). Contempra contributes to lowering the industry’s carbon footprint not only during the manufacturing process, but also beyond. While cement typically represents only 11% of a concrete mix, it accounts for more than 80% of all energy required to produce concrete. The environmental benefits are thus exponential. Once it is adopted for all suitable concrete applications, it is expected to reduce Canada’s greenhouse gas emissions by up to 900,000 tonnes annually. Contempra has been widely used across Europe during the last decade. Today, the European cement standard allows for Portland limestone cement made with up to 35% limestone content. These types of cement are the most popular cement sold in Europe today. The objective of the research presented in this paper was to assess the performance of concrete pavement made with Contempra cement in comparison with typical GU cement. This project, Highway 40 in Quebec near L’Assomption, was constructed on September  2011. 338m³ of concrete made with Contempra were placed and assessed. Three laboratories were present to perform quality control testing on the fresh and hardened concrete. It was noticed that the workability of the concrete was improved using Contempra due to its thixotropic behaviour. For given slump and air content values, concrete made with Contempra cement tended to show a better consolidation throughout the slipform paver than concrete made with GU cement. This resulted in faster and easier finishing operations.   Compared to laboratory testing, that showed faster set times and strength development for concrete made with Contempra cement, no significant changes were observed in terms of early age strength development. Saw cuts were made in a similar time frame and one day compressive strength was in the range of the actual standard deviation.   Finally, additional testing that could significantly affect long‐term durability of concrete pavement, such as freezing and thawing, salt scaling resistance, air‐void spacing factor, as well as chloride permeability were performed on both reference GU and Contempra concrete mixes. Test results for both concretes showed very similar behaviours.

Conference Paper Details

Session title:
Guillaume Lemieux
Jean‐Claude Leduc
sabelle Dupré