Repairing of cracks in concrete elements with resin-injection
RELATED MATERIALS
EPOMAX-EK Two-component epoxy putty
EPOMAX-L20 Two-component epoxy injection resin for cracks 0,1-1,0 mm wide
EPOMAX-L10 Two-component epoxy injection resin for cracks 0,5-3,0 mm wide
DUREBOND Two-component epoxy injection resin for cracks > 3 mm wide -Bonding agent
I. NATURE OF THE PROBLEM – REQUIREMENTS
Cracks in concrete elements (beams, slabs, columns, walls, etc) undermine the monolithic character and strength of the structural element.
II. SOLUTION
The materials used to restore a structural element to a complete monolithic piece, in order to ensure that it can function as originally designed, must have the following properties:
High mechanical strength
Strong bonding and great sealing ability
The appropriate viscosity, in the case of injectable resins, in order to be able to penetrate into the smallest gaps in the crack.
a) Resin injection into 0,1-1 mm wide cracks
Suitable materials:
EPOMAX-L20 injectable epoxy resin
EPOMAX-EK epoxy putty
b) Resin injection into 0,5-3 mm wide cracks
Suitable materials:
EPOMAX-L10 injectable epoxy resin
EPOMAX-EK epoxy putty
c) Resin injection into cracks over 3 mm wide
Suitable materials:
DUREBOND injectable epoxy mortar
EPOMAX-EK epoxy putty
III. APPLICATION
The complete resin injection procedure is as follows:
Any existing plaster in the area of the crack should be removed and the surface of the concrete must be cleaned thoroughly.
The crack is sealed with EPOMAX-EK epoxy putty, using a spatula. At the same time the nozzles are positioned and fixed along the entire length of the crack, at approximately 20 cm intervals, with the same material.
Once the EPOMAX-EK has hardened, the resin injection procedure is carried out, using either EPOMAX-L10 or EPOMAX-L20 injectable epoxy resin or DUREBOND injectable epoxy mortar, depending on the width of the crack:
a) The resin outlet tube (eg. a leveled tube) is placed in the first nozzle. If the crack is horizontal, the procedure starts from one end, if it is vertical, from the lowest nozzle.
b) By manipulating the resin outlet tap on the pressure pot, the resin is forced into the nozzle until it starts to come out of the next nozzle, or until it is impossible to apply more pressure.
c) The first nozzle is sealed with the special cap, then the resin is forced into the immediately adjacent nozzle until it starts to come out of the next one, and so on.
d) The procedure mentioned above is carried out on all the nozzles. The next day the nozzle projections are removed, by being broken off, and any pre-existing plaster may be restored.
IV. REMARKS
Throughout the application, one person should hold steady the outlet tube in the nozzles, cap the nozzles and direct a second person on the manipulation of the resin outlet tap.
The mixture of the epoxy materials must be carried out with great care, so that the whole of components A and B are used each time.
It is recommended that EPOMAX-L10, EPOMAX-L20 and DUREBOND resins are not poured directly into the pressure pot, but, once the two resin components have been mixed in component A’s container, then this container is placed in the pressure pot. This avoids soiling and possible hardening of any remaining resin in the pot, making it useless.
Attention should be paid to the length of time required for application, in connection with the pot life of the material and the ambient temperature, so that the material does not harden during the resin injection procedure.
It is essential to clean the pressure pot and other equipment once the application is complete. This should be done with the SM-12 solvent (rinsing of the pressure pot and outlet tube with SM-12 under pressure).
Protective gloves and goggles must be worn during the injection procedure.
Before application, study the safety advice mentioned on the product’s labels.
