Growing urban populations and deteriorating infrastructure are driving unprecedented demands for concrete, a material for which there is no alternative that can meet its functional capacity. The production of concrete, more particularly the hydraulic cement that glues the material together, is one of the world’s largest sources of greenhouse gas (GHG) emissions. While this is a well-studied source of emissions, the consequences of efficient structural design decisions on mitigating these emissions are not yet well known. Here, we show that a combination of manufacturing and engineering decisions have the potential to reduce over 76% of the GHG emissions from cement and concrete production, equivalent to 3.6 Gt CO₂-eq lower emissions in 2100. The studied methods similarly result in more efficient utilization of resources by lowering cement demand by up to 65%, leading to an expected reduction in all other environmental burdens. These findings show that the flexibility within current concrete design approaches can contribute to climate mitigation without requiring heavy capital investment in alternative manufacturing methods or alternative materials.

The sustainability of concrete buildings and infrastructure must be considered both in terms of its benefits to society and the environmental impact associated with its use in construction. Production of Portland cement (PC), in particular, is energy intensive and generates a significant amount of carbon dioxide. Cement is, however, only a relatively small component of concrete and overall the material is resource efficient and has moderate embodied energy and carbon dioxide footprint. Concrete is widely used due to its low cost, ease of use, good track record, versatility, local availability, thermal benefits, acoustic dampening, and durability. Durability performance of construction materials is important, and concrete is often considered to be inherently durable due to its chemical and physical resistance to various environments and dimensional stability. Concrete structures are assumed to be largely maintenance-free and to provide long service lives. Figure 1 shows an 80-year-old concrete bri...