June 1, 2011
This last quarter has seen CG Flooring Systems complete its largest and most technically demanding floor joint repair project to date. The repairs to the concrete floor slab at a large distribution centre in Birmingham, UK took place over a 10 week period between February and April, which saw almost 850 linear metres of joint and crack repairs being undertaken. Over 600 linear metres required the concrete arris’ to be rebuilt using our tried and tested arris repair detail, or a modified arris repair detail, was used to treat large cracks within the warehouse floor.
An approach was made to CG Flooring Systems asking if we could provide a solution to repair the existing concrete joints and cracks in the warehouse floor. The challenging aspect of this project was to find a solution for the larger cracks that were present in the centre of the floor panels, which have joints at 12m centres. It would appear these cracks have effectively taken the place of an absent sawn joint. After an initial site visit and a further period of consultation with the client and their engineering consultant, it was agreed that a trial repair would be done and assessed over a period of time. The trial repair was a modified version of our Type 1 Crack Repair detail, which unfortunately was not successful. After a period of approximately 6 weeks, cracking around the repair detail was evident and this was obviously not an acceptable solution for the client.
Our initial thoughts based on the observations from the trial, were that the cracking could be caused by either poor load transference or thermal movement. A further visit to site took place to look at the floor in more detail under operational conditions and this involved monitoring the Materials Handling Equipment (MHE) as they passed over the floor. No physical or visual indications of differential slab movement were observed and it was agreed at the time that there did not appear to be a problem with the load transfer capabilities of the floor slab. It was therefore concluded that the appearance of cracking was a result of thermal movement. Subsequently it was decided the best solution for treating these larger cracks was to carry out a modification to our arris repair detail that would effectively leave them finished as a meandering joint. The key to the success of the modified floor repair detail was to ensure the crack was mirrored through the repair detail and this was achieved by pre-forming the joint sealant and applying in strips along the path of the crack. The specialist CoGri Repair Mortar was applied either side of the joint sealant, prior to finishing the repair flush with surrounding floor profile, to ensure a smooth transition over the floor for the MHE.
This was a technically demanding project that required no shortage of skill and patience from the Technicians on site, as they carried out the repairs with the clients operation continuing around them. A project of this nature highlights the benefits of using an industrial flooring specialist, who not only understands the issues of dealing with a concrete floor slab, but also takes pride in understanding how the floor is used by the customer. CG Flooring Systems called not only on their years of experience in repairing concrete floors, but were also able to call on the experts within the CoGri Group of companies, to ensure the best possible solution was available for the client.
For a site visit or advice on the best solution, contact the experts.