Crack repairs can be tricky but DAMA is here to help with our unique Screedshield® System developed for us by TPR Systems.
Screedshield® is used for remediation of delaminated, cracked or otherwise failed concrete slabs on grade or structural. The Screedshield® System has been developed in line with the requirements of BS EN 1504, “Products and systems for the protection and repair of concrete structures – Definitions, requirements, quality control and evaluation of conformity”.
The Screedshield® System relies on three steps to remediate the problem. Much depends on whether the slab has achieved equilibrium or not and whether or not the cracks are simply shrinkage related or the result of dynamic loading resulting in the formation of yield lines (hinges, live cracks).
The three steps to the Screedshield® System are:
Stabilise:
This involves the use of an ultra low viscosity MMA (TPR R41) which is allowed to penetrate all openings at the surface of the substrate and soak into any voids or gaps. The volume of material used depends on the porosity of the substrate. The polymerisation of the TPR R41 within the mortar matrix locks the finished system into the substrate.
Stabilisation may also involve the use of TPR F10 to penetrate and fill cracks in excess of 1mm width. This is a material that is flexible and can stretch by up to 400%. It also chemically welds itself to the TPR R41 and is extremely useful for dealing with live cracks.
Large voids or steps can be dealt with by a combination of grinding and/or filling with TPR R17 which is a resin bound aggregate filler material.
Reinforce:
To prevent the stabilised substrate from cracking again (eg: as a result of hogging moments exceeding the tensile capacity of the substrate) it may be necessary to increase its flexural strength at the surface. We achieve this using a proprietary 45º reinforcement which is bonded to the stabilised surface with TPR RU380 or TPR RU320. The material provides continuity of reinforcement on a 45º grid which enables tensile forces to be resolved with minimum shear applied to the bond. The grade of reinforcement applied is calculated and varied according to the increase in flexural strength required.
Protect:
To protect the repairs and ensure the slab longevity is enhanced and not compromised the Screedshield® System is coated with the very heavy duty TPR Quartz system which provides high impact resistance, uniformity of colour, heavy duty abrasion resistance, slip resistance and waterproofing of the substrate. The TPR Quartz system can be extremely hard or flexible to accommodate requirements of the substrate in service.
All TPR Systems materials are fully cured within an hour of installation and works can be carried out during evenings or weekends without disruption to the clients business.
If you want more information on Screedshield® or any Dama product or service give us a call or contact Dama.