Assessing the Sustainability of Alternative Shaft Construction Methods

Abstract

Reducing carbon dioxide (CO2) emissions is a global priority. The concrete industry has a major role in this reduction since it accounts for about 8% of global CO2 emissions. Despite significant improvements in the sustainability of the production of concrete, one of the best solutions is still to improve the design and construction methods, such that the required quantities of concrete are reduced. Using, as a reference, a real case study, this study compares alternative shaft construction methodologies from engineering and sustainability points of view, highlighting the advantages and drawbacks of each solution. To achieve this purpose, a back analysis is performed to ensure that the numerical model is accurately calibrated and the shaft construction methods can be adequately assessed. The results show that, while the considered methods are applicable and satisfy engineering requirements, the characteristics of the lining of the shaft could have been optimized, resulting in a reduction in CO2 emissions by at least 50% without compromising the safety of the construction.

Keywords

• sustainability
• shaft excavation method
• numerical modelling