Sealing holes after clamping screws

Sealing of shuttering holes is a necessary and very important stage when pouring any reinforced concrete structures. Coupling screws are used to fix the formwork panels, and after their removal, through holes remain in the concrete body, which must be properly and securely sealed.

The best way to seal the holes from the tie screws is to use a bentonite cord and a repair mixture.

The bentonite cord of the SANPOL Hydrostop consists of 75% bentonite clay, which, when in contact with water, tends to swell and increase in volume, thus filling voids and reliably sealing the concrete structure. 

How to seal holes:

We cut the cord 10 cm shorter than the thickness of the formwork, use a round bentonite cord with a diameter of 22 mm, insert it inside the hole.

On both sides, we seal the hole with a thixotropic repair compound Teknorep 300EX. 

Teknorep 300 EX is a one-component non-shrink repair compound with increased bending strength, which includes polymer fibers. The material has a number of advantages: it does not shrink, is easy to apply, has high compressive strength, resistance to concrete carbonation, is used in structural repairs, is suitable for vertical and horizontal applications.

Sealing the holes from the tie screws with ordinary sand-cement mortar, of course, you will reduce the cost, but such seals soon shrink, crack, fall out or leak water.