High-Performance Concrete Cover – A Smart Way to Increase Service Life and Reduce Co2

Reduction in CO2 emissions of reinforced concrete construction is critical to mitigate the effects of climate change. Durable infrastructure with a long service life is not only an important part of CO2 reduction but is a general sustainability objective for society. However, durable concrete construction traditionally uses high cement content mix designs and increased concrete cover which can increase member thickness. Both will typically result in increased CO2 emission. Use of supplementary cementing materials is acknowledged as being the primary means to reduce CO2 emissions in concrete, but other methods that further reduce emissions include smart construction techniques that either reduce the volume of concrete used or maximize the use of low cement content mix designs. This paper discusses the method of applying a bonded cement-based high-performance shotcrete or hand-applied mortar layer to create a high-performance concrete cover (HPCC) over a low CO2 emission concrete core. Case studies will be presented where this technique is already in regular use for both new construction and restoration to provide enhanced cover properties and replace cover deficiencies. Possibilities for further use of the method will be discussed.