Sustainable Structural Design: Lessons from History

As issues of sustainability in the design of infrastructure are in the starting phase of being addressed, historical case studies can illustrate successful and unsuccessful designs. The article presents two sustainable bridge types which have survived for centuries and continue to carry traffic today: a Roman arch bridge and an Inca suspension bridge. Each bridge is made from natural materials and each is well-suited to its design task. Both bridges offer important lessons for today's engineer seeking to learn more about the philosophy of sustainable structural design.