Rebar is a barbed steel rod used for the reinforcement of concrete slabs. The product is placed beneath the surface of the cement prior to smoothing the surface. Rebar is not extremely expensive but can corrode over time if exposed. Any cement structure, no matter how small, needs reinforcement to be stable. Alternatives to standard rebar include plastic replacements, corrosion-resistant steel rebar and the use of direct alternatives.
Fiber-Reinforced Plastic (FRP) is a relatively new product. The product follows design specifications for classical steel rebar but is made out of plastic and plastic composites that use various types of fiber to add strength and flexibility to the product. The use of plastics and fibers helps to prevent the corrosive damage that occurs with normal steel due to salts in the cement and surrounding ground. The costs associated are slightly higher, but the long-term benefits promote a more stable and enduring structure.
Steel is stronger and more sturdy than most other replacement options for rebar. The downside to steel is the chemical reaction with salts in the ground and concrete. The resulting corrosion degrades the quality of the concrete slab. Steel rebar in concrete allows for thinner slabs, but corrosion makes the thinner slabs more prone to cracking and damage. Modern engineering has developed steel alloys that combine the strength of steel with a high resistance to corrosion or rust. Stainless steel offers this level of protection but was cost prohibitive for use as concrete reinforcement. Engineering techniques allow for similar protection as stainless steel at more economical rates.
Direct alternatives to rebar include the use of aggregate materials or metal mesh. Metal mesh ranges from chicken coop wire to fencing. Any type of metal mesh that you may have lying around can be used as a substantial support for concrete. Treated metal fencing works very well as a form of reinforcement for small cement slabs. Aggregate materials are stones and rocks used as a filler material for a concrete slab. Rather than blindly dumping rocks into a concrete mold and then pouring the cement on top, adding large chunks of stones or rocks to the mix before pouring allows the cement to be more stable over a longer period.