Crack Formation and Control Strategies in Concrete Systems

Abstract

Concrete cracks in buildings are a common and routine occurrence that occurs in civil engineering, regardless of the nature and size of the work. It is almost unavoidable due to the nature of concrete material, i.e., its weak tensile strength, and for several environmental and structural reasons. The cracks not only deteriorate the aesthetic finish and appearance of the buildings but, above all, compromise their mechanical stability, safety, and life. They result in the weakening of major structural members such as slabs, beams, and columns, and thus destabilise the building. Concrete cracking is initiated by a number of causes, such as construction defects, defects in design, poor-quality materials, defective curing, and environmental factors such as variations in temperature, shrinkage, or chemical reaction. Engineers and scientists have been working hard over the past couple of years with the aim of understanding the crack initiation and propagation, with the aim of utilising appropriate preventive and corrective action. Detection and structural vs. non-structural differentiation of cracks are now possible, as the majority of them are obligated to carry out the right type of repair jobs. Their ability to repair is a factor of knowing the right repair method and material, depending on the width, direction, location, and level of the crack. There are cracks that are surface minor imperfections and others that are inherent flaws that require treatment with some level of urgency. This paper aims to induce cracking in concrete structures, i.e., causes, nature, and effects of some patterns of cracking in general. It also provides prevention strategies and remedial techniques, i.e., chemical injection, control joints, reinforcement, and advanced repairs such as epoxy injection, stitch cracking, and dry packing. Proper practice during construction and vigilant observation of structures have been stressed. They are significant steps in averting further increases in cracks. In short words, understanding causative causes of crack initiation and respective remedies can go a long way in the durability, safety, and performance of concrete structures over their required period.