Surface Sealing and Crack Repair Definition

1. Downloaded from: justpaste.it/c7eqn Surface Sealing and Crack Repair Definition In order to stop the infiltration of water, chlorides, and other impurities, fissures occasionally need to be sealed. The methods described in this section only deal with sealing the cracks at the concrete's outside surface, but other crack sealing procedures can restore capacity or offer total filling of a fissure. First Approach: Rout and Seal Cracks When a limited amount of movement is expected owing to service loads, thermal impacts, or other factors, routing and sealing cracks can be an efficient technique to stop water infiltration. The Contractor must use a grinder to cut a V-shaped groove with the crack placed in the center of the groove while routing a crack. Bond breaker tape needs to be put at the bottom of the groove for cracks where there will likely be a lot of movement before sealing. To be effective, the tape needs to remain at the bottom of the groove. Due to the bond breaker, adhesion is only allowed on two sides as opposed to three, which greatly increases the sealant's flexibility. NOTE: Although in theory a nice idea, it is challenging to lay bond breaker tape in the bottoms of the grooves such that the tape won't move when the sealant is applied. The bonding surface on one side of the joint may be reduced or eliminated if the bond breaker goes up, which would render them ineffective. 2nd technique: surface sealing Applying an adhesive directly over the crack will suffice to seal its surface and stop water, chlorides, and other impurities from seeping in. Only when no considerable fracture movement is predicted should crack surfaces be sealed. This is relevant for small fractures in compression members as well as cracks in prestressed members brought on by fabrication, tensioning, or handling difficulties. Work the epoxy into the fracture before wiping away any extra before it hardens.

2. Commentary Gravity-feeding epoxy is a useful tool for sealing crack tops. The depth of penetration, however, may vary. Use it only in places with shallow cracks or where bigger fissures are acceptable but need to be protected from water and chloride infiltration. The tops of cracks can be effectively filled with gravity-feeding sealant. However, the penetration depth can vary, and frequently it won't go further than 14" into the fissures. Gravity-fed sealants are primarily used to repair very small bridge deck cracks; when applied properly, they provide a barrier that prevents water and chloride from penetrating the reinforcing steel.