Sealing moving cracks and non-moving cracks
In developing a suitable method to seal up cracks detected on concrete surface, it's of paramount importance to conclude if further movement will be expected for the cracks. If the crack isn't expected to move further, it's sufficient to brush cement grout into it. For wider cracks, other materials such as latex-cement mixture can be considered for sealing the crack.
When further movement is expected for crack, seals wider than cracks are suggested to be applied over the crack in order to decrease the strain around it to an acceptable level. Furthermore it's desirable to apply the treatment when cracks are widest so that sealing material isn't subject to further extension. Care must be taken to prevent bonding of sealing material with the bottom of crack to confirm that only direct tension forces are experienced in sealing material.