Why All Roads Lead to Concrete Paving for economy and the environment By Sherry Sutherland, M.A.Sc, P.Eng., LEED AP C oncrete pavements are known for their strength, durability, and longevity. In the past, they have also been associated with a high initial price. However, in a number of lifecycle cost studies, concrete pavements prevail due to the significantly lower maintenance and rehabilitation needs.1 The initial price still remains at the forefront of owners’ minds, but many do not realize concrete pavements are now competitive on a first-cost basis. The new paving realities are that comparative initial bid cost and lifecycle cost assessments increasingly favour concrete over asphalt in the foreseeable future, essentially allowing municipal owners to eat their cake and have it too.2 Public officials across the country are faced with the increasing challenge of managing road assets on a stagnant—or in some cases, decreasing—budget. It is essential that an agency critically evaluates its paving material options and determines the best course of action when spending taxpayer dollars. Concrete pavement basics Due to its versatility and durability, concrete is the most widely used construction material in the world. In fact, it is second only to water as the most consumed substance on earth.3 Concrete is an inorganic and inert material produced by mixing cement, supplementary cementitious materials (SCMs), water, fine aggregate (i.e. sand), and coarse aggregate (i.e. gravel or crushed stone) with or without various admixtures, reinforcement, fibres, or pigments. Types of concrete pavements There are three basic design types and each can provide long-lasting concrete pavements that meet or exceed specific project requirements. Jointed plain, jointed reinforced, and continuously reinforced concrete pavements are all suitable for new construction, reconstruction, and overlays of existing roads (Figure 1). 22 January 2010 Construction Canada CC_JanFeb10.indd 22 12/22/09 11:55:37 AM Image courtesy Ross Monsour, RMCAO Feature