Buildings Crack

Joshua Gaquit

Arnel Christian Minierva

Most buildings crack at some time during their service life. The appearance of cracks is a symptom of distress within the fabric of the building. Often the cracking is of little consequence and once it is established as static, simple repair by filling or re-pointing is all that is required. However a crack maybe the first sign of a serious defect which may affect the serviceability or the stability of the building. The appearance of cracks can also affect the value of the building, its insurability, the saleability and can be the subject of litigation. Therefore correctly assessing the significance of cracks is essential. However it is a far from a simple task and is often a subjective exercise. The implications of an incorrect assessment can lead to expensive and unnecessary remedial work. In some instances the remedial work may exacerbate the problem resulting in yet further and more extensive cracking.

The most common materials for damage repair works of various types are cement and steel. In many situations non-shrinking cement or an admixture like aluminium powder in the ordinary portland cement will be admissible. Steel may be required in many forms, like bolts, rods, angles, channels, expanded metal and welded wire fabric. Wood and bamboo are the most common material for providing temporary supports and scaffolding etc., and will be required in the form of rounds, sleepers, planks, etc. In restoration of work, it is important to realise that even fine cracks in load bearing members which are unreinforced, like masonry and plain concrete reduce their resistance very largely. Therefore all cracks must be located and marked carefully and the critical ones fully repaired either by injecting strong cement or chemical grout or by providing external bandage. The techniques are described below along with other restoration measures. The external surfaces are cleaned of non-structural materials and plastic injection...