Trade Journals for the Concrete Industry

Cracks are a normal, but controllable state of reinforced concrete; the SLS (Serviceability Limit States) limits their opening. If cracks do not exceed a certain aperture, they do not reduce the structure’s strength or the structure’s serviceability. Current building codes, such as Eurocode 2, focus on durability and serviceability, such as preventing mesh reinforcement corrosion and preventing cosmetic damage and ensuring water-tightness. This immediately implies limiting the opening of cracks. For reinforced concrete, the rules and formulas for calculating crack opening are state of the art. Usually this involves imposing a minimum mesh reinforcement. Aside from the minimum mesh reinforcement for controlling the cracking, there are other rules to determine the minimum mesh reinforcement to ensure the ductility and safety of a structure (Ultimate Limit State). Even by applying these minimum reinforcement rules, excessive cracking of reinforced concrete is a common problem.