In devising a suitable method to seal up cracks detected on concrete surface, it is of paramount importance to determine if further movement would be expected for the cracks. If the crack is not expected to move further, it is sufficient to brush cement grout into it. For wider cracks, other materials like latex-cement mixture may be considered for sealing the crack.
When further movement is expected for the crack, seals wider than the cracks are recommended to be applied over the crack in order to reduce the strain around it to an acceptable level. Moreover, it is desirable to apply the treatment when the cracks are widest so that the sealing material is not subject to further extension. Care should be taken to prevent bonding of sealing material with the bottom of the crack to ensure that only direct tension forces are experienced in the sealing material.
This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.
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