EcoSmart concrete was used for the piles pile caps and precast panels of the new light station at Sandheads. High volume fly ash -HVFA- concrete provides greater strength and less permeability which will result in a higher durability in the harsh marine environment. In the case of this project the slower setting time of HVFA concrete was beneficial as the concrete trucks had to be brought to the site by tug boat and barge increasing the time that the concrete was in the trucks before pumping and placing. The manufacturing of the concrete for the Sandheads Light Structure avoided approximately 44% of the C02 emissions that manufacturing of conventional all-cement concrete would have created.
Case Study Report Author: Brian Konrad
As this case study illustrates implementing EcoSmart concrete technology is particularly challenging in remote areas of Canada. Availability of fly ash limited or lack of experience with the use of fly ash in concrete limited competition for concrete supply and cold and rainy weather conditions all contributed to the challenges of introducing EcoSmart concrete on this project. To overcome these challenges a strong commitment to â€œgreenâ€ construction and collaboration among stakeholders are needed.
The beginning stages of EcoSmart concrete implementation on this project were very successful in terms of increasing the knowledge about this technology among new users. In the end however EcoSmart concrete was not used on this project.
This report summarizes the steps taken during the design and tender stages of the project as well as outlines the steps that a similar project would need to take to continue with the implementation of EcoSmart concrete during the construction stage.
Case Study Report Author: EcoSmart Concrete Project
The Greater Vancouver Regional District -GVRD- is constructing a 38.5 million gallon reservoir at Little Mountain Vancouver. The Project is known as the Little Mountain Reservoir Reconstruction -LMRR- . The use of EcoSmart concrete at the LMRR demonstrates that this type of concrete is ideal for large infrastructure projects. The resulting wall concrete evaluated here had in excess of 35% fly ash replacement for portland cement resulting in significant GHG reductions at no premium cost.
The concrete had excellent workability resulting in corresponding excellent surface finishes. It was readily pumped and consolidated even at slumps that would be considered low for the wall configuration. High durability necessary for the 100 year design service life was demonstrated by low porosity and permeability in concrete tests. In addition the concreteâ€™s high resistivity will assist in long term passivation of the reinforcing steel from corrosion. As is typical of concretes containing higher fly ash replacements slower setting times and lower early age strength resulted. However the in-situ strength of the semi-massive walls concrete was adequate to achieve conventional formwork stripping schedules. Finally use of EcoSmart concrete achieved relatively low shrinkage which resulted in crack-free walls and supported control joints at larger than normal spacings.
Case Study Report Author: Levelton Consultants Ltd