Concrete Regulations Stand in the Way of Sustainability Ambitions

Abstract

The Dutch Concrete Act sets ambitious goals for sustainability, including significant CO2 reduction and high-quality reuse of concrete by 2030. Rijkswaterstaat, the Directorate-General for Public Works and Water Management, aims for circular practices by this time. Structural engineers play a crucial role in assessing existing structures. But too often it leads to the replacement of a structure because it is at the end of the designed service life. Concrete regulations influence engineering decisions, with changes increasing the use of reinforcement, although they may offer more flexibility than perceived. Structural engineers can influence sustainability by professionally assessing existing structures, potentially avoiding unnecessary replacements. However, there’s a tendency to prematurely classify structures as old, leading to conservative assumptions and modelling methods that may underestimate the structural safety. Despite limited technological advancements in concrete and reinforcement steel, existing structures often exceed strength requirements for new structures. Shear force requirements have evolved, yet structures without shear reinforcement are feasible under current regulations. The emphasis on reuse over new construction is proposed, urging a reconsideration of the necessity of shear reinforcement. Structural engineers can optimize material use by carefully considering modelling methods, structure dimensions and reinforcement amounts, aligning with the basic principles of reinforced concrete techniques while following the regulations.