Estimating on-site emissions during ready mixed concrete (RMC) delivery: A methodology

Sustainability represents a critical challenge in the construction industry and many approaches have been developed to reduce the environmental impact of on-site construction processes. However, scant academic attention has been given to the environmental impact of logistical support for ready mixed concrete (RMC) on-site delivery emissions in developing countries. This paper develops a methodology for capturing emissions from RMC equipment and material during on-site delivery operations. A literature review was conducted to define and delineate upon greenhouse gases emitted during RMC operations and the appropriate methods to calculate them. A methodology was then developed and validated by analysing ten delivery cycle times in a case study. Data collected was analysed using simple descriptive summary statistics (viz: mean, bar charts and standard deviation). The study's results illustrate that on-site emissions incurred were: CO2 account for 99.38 % of the total emissions from RMC equipment while HC (0.03 %), CO (0.11 %), NOx (0.26 %), PM10 (0.02 %), and SO2 (0.20 %) account for 0.62 %. Embodied CO2 in RMC also contributes majorly to emissions in on-site delivery operations. Alternative materials such as fly ash represent a viable means of reducing embodied emissions in RMC but proper handling is required to avert harmful environmental impacts. The study provides deeper insights into the on-site emissions arising from RMC delivery operations and a bespoke methodology that could be used as an organisational learning tool for RMC companies. (C) 2020 The Authors. Published by Elsevier Ltd.