Final answer:
Steel reinforcing is commonly used in concrete to enhance its tensile strength. Steel and concrete have similar coefficients of linear expansion, allowing them to expand and contract without causing thermal stress. Reinforced concrete is crucial in construction for its strength, longevity, and thermal protection, though it does require maintenance against corrosion.
Step-by-step explanation:
Most of the time, steel reinforcing is used in concrete to strengthen the concrete in tensile situations. While concrete is inherently strong in compression, it lacks sufficient strength in tension. This is where steel comes in handy, as it is strong in both tension and compression. The use of reinforcing rods, or rebar, made of steel in concrete is crucial because steel's coefficient of linear expansion is almost identical to that of concrete. This similarity helps prevent thermal stresses that can cause cracks as the materials expand and contract at nearly the same rate.
In addition to bridges and highways, where expansion gaps or steel I-beams are utilized to reduce bending strains and allow for thermal expansion, steel reinforcement is prevalent in structures subject to flexible demands, such as ships' superstructures, metro trains, and even in overhead power cables that contain a steel core for added strength. Moreover, modern construction makes use of lightweight concrete, which includes a mixture of lightweight coarse aggregate with fine aggregates, providing advantages such as reduced load and more efficient building rates, along with being a durable material that acts as an excellent thermal protector.
While steel reinforcement greatly enhances the strength and longevity of concrete structures, consideration must also be given to potential issues such as corrosion, which can undermine the structural integrity over time. This necessitates regular maintenance and monitoring to ensure safety and the full benefits of reinforced concrete, as historically seen in catastrophic events like the collapse of the Silver Bridge due to corrosion.