A Method for Considering Variability in the Environmental Impact of Concrete

The construction industry faces an extraordinary challenge to reduce its environmental impact. An essential precondition for this effort is an objective measure of the environmental indicators for different construction materials. The authors propose a probabilistic approach similar to the concepts already established in structural reliability. To this end more than a 100 EPDs for concrete from all around the world have been gathered and analysed statistically. The large number of outliers in the data points to inconsistencies in the environmental assessment between the program operators. The analysis revealed that the global warming potential (GWP), the abiotic depletion potential for fossil resources (ADPF), the total use of renewable primary energy resources (PERT), the total use of nonrenewable primary energy resources (PENRT) and the use of net fresh water (FW) can be approximated by a normal distribution. Furthermore, a correlation between the cubic compressive strength of concrete and the GWP, PERT and PENRT could be established. The regression line obtained can serve as an estimate for the mean of the GWP depending on the concrete grade. In essence the statistical analysis of EPD data yielded valuable insights into the environmental impact of concrete and is therefore a method which can be an important tool on our way to a sustainable society.