Liebherr ensures cost savings in Brazil
By Richard High14 July 2009
Brazil is not generally associated with tower cranes despite its hi-rise towers preferring instead to use materials hoists. However, as labour costs rise use of tower cranes on the plethora of high-rise projects around the country is starting to rise.
Sao Paulo-based contractor ETC is one company currently changing its modus operandi when it comes to using tower cranes for site lifting duties.
Marcos Fernandes, project manager at ETC has many years experience of Brazil's construction sector, while ETC has for many years been recognised as an earthmoving and transportation specialist.
However, as more and more high-rise projects spring up around Sao Paulo the company has begun to win more and more work in the sector.
It is currently using a Liebherr 71 EC-B tower crane for the first time on a three-tower condominium project in Casa Verde, a suburb 5 km north of downtown Sao Paulo.
ETC undertook a feasibility study into the use of a tower crane compared with the traditional hoist concept and as a result, said Mr Fernandes, opting for the country's first Liebherr 71 EC-B ‘topless' tower crane for its ease of erection and dismantling.
According to Mr Fernandes, the study indicated a payback of just five years. "It is extremely expensive to rent a new crane in Sao Paulo, with a typical rental rate of BRL 35000 (US$ 17800) per month. We also estimated that we would need 25 fewer labourers ensuring a further saving of around BRL 18000 per month (US$ 9130)," he added.
Bordered on three sides by busy roads, the three towers -Solaris, Vitalis and Acqua - are 20, 23 and 23 storeys respectively.
The site features an underground car park plus two above ground parks over an area of 4282 m2. All three towers rise above the second floor terrace level and offer 228 apartments.
With a ‘footprint' of 300 m2 the Solaris tower provides 15 floors of apartments before reducing its ‘footprint' to 200 m2 for a duplex and triplex apartment; with a final height of 70 m.
The Vitalis and Acqua towers offer 18 floors of standard three-bedroom apartments with a ‘footprint' of 370 m2 reducing to 300 m2 for a duplex and triplex to provide a final height of 80 m.
According to Mr Fernandes, ETC were able to complete a floor cycle in one week, which while comparable to using a hoist system, meant it was able to reduce the workforce required by 25.
The 71 EC-B is used extensively to lift rebar, timber formwork and concrete, placing it where required, saving not only the reduction in labour but significant time savings.
"We still use the hoist for small material lifts such as sand and blocks for the wall infill, plus of course the workforce," explained Mr Fernandes.
The 71 EC-B is strategically positioned on Vitalis, the centre tower and features a 50 m jib, which is able to cover both Vitalis and Acqua and 75% of Solaris.
With two tie bars on the external walls of the tower, the crane will have a final hook height of 89.20 m.
Having previously only worked on traditional hoist operations, Mr Fernandes is now a convertee for tower cranes.
"It is so much more efficient and provides so many cost saving benefits," he said.
ETC is expected to start work on its second condominium project at the end of the year - a high quality 29-storey tower with a terrace, lobby area of leisure and three underground car park levels.
"Without a doubt we will be transferring the Liebherr crane to the project next year in March/April," he said. "We have, together with sister company and developer, Incorportec, a goal of one condominium project a year and will definitely be looking at the Liebherr tower crane option for future projects."
CAPTION: Brazilian contractor ETC takes delivery of the country's first Liebherr 71 EC-B tower crane for a triple tower condominium project in Sao Paulo