Lightweight Floor Screeds
Foamed Concrete was chosen as a suitable floor screed by contractor Korman Homes to seal and screed the floors of some 60 apartments on its new hotel and leisure complex in Famagusta , Northern Cyprus.
The contractor had a knowledge of foamed concrete and recognised the benefits that it would bring to their development but had never used the material previously or indeed had any equipment with which to make or pump the foamed material.
Propump Engineering were contacted via our web-site and became involved with an associate company of Korman homes, AMPC Ltd.
The screed was required to be poured to a depth of some 150mm be capable of being pumped vertically 25 metres and exhibit good thermal and acoustic properties. Following a number of trials a foamed screed mix was designed that potentially satisfied all of the clients requirements. Once the material specification was satisfied the client now required a means with which to manufacture and place the foamed concrete screed mix. Within our stock of reconditioned plant and equipment we had a self contained trailer unit. This unit comprised of a hopper and agitator, high pressure electric foam generator, computer controlled management circuit, Sp 50 squeeze pump and a diesel power generator.
The unit was self supporting and only needed a supply of pre-mixed base materials in order to produce high quality foamed concrete’s at a range of densities. The client owned and operated a number of Readymix plants in Cyprus so the supply of pre-mixed base materials was not a problem so the system suited their requirements perfectly. The system had been reconditioned in our own workshops and was available for immediate dispatch.
To produce the pre-formed foam our protein based Propump 26 was utilised and both machine and chemical were shipped to Cyprus.
Working on a consultancy based fee, Propump attended site for a number of days to fine tune the mix and machinery, and to train the operatives in the use of the equipment.
The chosen mix had a plastic density of 800kg/m3 and was based on a 1 part cement to 1 part sand, base material and was found to be ideally suited to the extreme temperatures experienced in Northern Cyprus . The water cement ratio was kept high and this proved invaluable in keeping the base materials fluid during their journey from the concrete batching plant to the construction site, a journey that took upto 1.5 hours in temperatures of 25-30 Degrees Celcius.
Once the foamed mix and the foaming plant were proven at ground level, the foamed concrete was pumped vertically up 25 metres with both the equipment and the foamed concrete performing well. The density of the foamed concrete remained the same despite the 25 metre vertical lift, with the foamed screed exhibiting the same characteristics after being pumped up 25 metres as it did when it was simply pumped at ground level.
The final foamed screed was extremely fluid and practically self levelling. It pumped easily, with the operatives able to pump and level some 200 square metres in approximately 1 hour.
The initial on site trials were completed in late April 2005 with 25% of the project completed by early May 2005.
The client is currently investigating the use of different materials to aid the setting time and increasing the final strength of the foamed concrete with to date extremely encouraging results.