All metals have the natural tendency to revert to the lesser energy state of iron. In other words, this natural phenomenon is well known as CORROSION, and is commonly seen on iron ore or rust. Steel is an excellent building material – it is readily available, highly recyclable and has a high strength-to-weight ratio and relatively long durability. However, it is inevitable – steel corrodes.
Though corrosion may be more visible, all building materials (concrete, plastic, wood, etc.) diminish and decay over time. Bare steel is more obvious – it will show alerting signs at problem areas. But steel used inside structure, for example, as reinforcement in concrete may not show any visible signs of corrosion until it is too late and catastrophic disaster may happen – being tragic and extremely costly.
Steel corrosion is costly – nearly $423 Billion are spent annually in the US for repairs and corrosion prevention actions. Public infrastructure is the one that suffers the most from corrosion. In the end it means taxes are paid for the inevitable problem that has a real and natural solution to it.
The long-held attitude in public construction of cheapest bid wins has been already proven flawed. Building with the cheapest methods and materials often means greater costs in future.
However, the problem of corrosion is not only costly money-wise. Beyond the huge funds outlaid to repair and/or replace corroded and/or decaying structures there are indirect costs (natural resources, potential hazards, and lost opportunity). When a project is constructed with a building material that is not able to withstand environment it is exposed to within the length of its design life, natural resources are needlessly consumed to continually repair and maintain the structure. Wasting natural resources is a direct contradiction to the growing focus and desire for sustainable development to benefit future generations.
In addition to the waste of natural resources, building structures that cannot sustain their environment can lead to hazardous situations. Accidents caused by corroded structures can lead to huge safety concerns, loss of life, resources, and more. One failed pipeline, collapsed bridge or other catastrophe may cause huge indirect costs (more traffic delays, loss of business, etc.) and public outcry. Depending on which market sector (industrial, infrastructure, commercial, etc.) is being considered, these indirect costs may be up to ten times bigger than direct cost.