The concrete industry is lowering carbon emissions by looking for cement alternatives and substitute aggregates, as well as pursuing carbon sequestration for cement, writes engineer Kelly Roberts, a principal in Walter P. Moore’s Structural Group. “To make a meaningful impact, most projects will need to take a multi-faceted approach by incorporating cement reduction, cement replacement, and a variety of new technologies,” Roberts writes.
Another emerging technology in concrete production is to utilize carbon sequestration and injection. Technologies such as CarbonCure, CarbiCrete, and Solidia have been emerging in markets around the country.
Nationally, Walter P Moore used CarbonCure on a variety of project types and concrete applications. For a commercial office building development in Atlanta, our team was able to work with the concrete supplier for the drilled pier foundations to inject CO2 into the concrete mixture at the batch plant and reduce the cement content by 7% for that application.
This technology and technologies similar to it, when used in combination with other cement alternatives such as traditional supplementary cementitious alternatives can help project teams achieve embodied carbon reduction goals on their projects.
In order to evaluate the relative environmental impact of different technologies and cement alternatives in various concrete mixtures, it is important to have environmental product declarations (EPDs). EPDs quantify the environmental impact of materials across multiple environmental categories including global warming potential.
While different technologies and cement alternatives can each tout their benefits, their proven impact is truly only verifiable with mix-specific EPDs. The demand for product-specific EPDs on projects is certainly growing and producers should expect to see this more and more in specifications in the coming years.