Inspire : Public Works May Jun 2013
52 Public Works Professional May-June 2013 FIBRE REINFORCED CONCRETE FOR FOOTPATHS PAUL TATHAM SENIOR ENGINEER PROJECT/DESIGN, COUNCIL OF CITY OF SYDNEY, ASKS: Has anyone used fbre reinforced concrete for footpaths instead of steel reinforced concrete? If so, what material was used, how successful has it been and did it increase the total cost for each job? ARTHUR INGLIS INFRASTRUCTURE PLANNER, WELLINGTON SHIRE COUNCIL, SAYS: We used it on a subdivision development at the request of a contractor, but we won’t be approving it for further subdivisions due to defects during the defect period. The Infrastr ucture Design Manual adopted by Council requires 125mm reinforced paving, which will be the minimum for all future developments. SALLY ROZEMULDER REGIONAL RISK MANAGER, STATEWIDE MUTUAL, SYDNEY, SAYS: We used steel fbres in Gunnedah for cycleways a couple of years ago and it was cost neutral. But everyone had to wear gloves so as not to get fbres in their hands. The quality was similar to reo, but we will have to wait and see how it goes over time. MARK WOOD DIRECTOR PUBLIC WORKS & SERVICES, WAVERLEY COUNCIL, SAYS: We have used a plastic fbre as steel reinforcement on several projects. You are welcome to come and have a look - we have a site at Bondi or Bronte. We’ve been using an EPC product (Barchip R50). VANESSA DUTTON SOUTHERN REGION MANAGER, PROPEX CONCRETE, MCLAREN VALE, SAYS: Here are some answers: Micro fbres are for plastic shrinkage cracking, preventing explosive spalling, increasing abrasion resistance or extending the life of infrastructure in or near water. As they reduce plastic shrinkage cracking, they reduce permeability of concrete providing protection to the steel reinforcement that is the key to str uctural support. Macro fbres are polymer fbres for replacing traditional mesh reinforcement. We supply Novomesh 950 for pavements. Steel fbres are mainly for heavily loaded pavements or slabs. We advise councils not to use steel fbres in public areas. If one extr uded from a pavement it could cause injury. Macro fbres (called plastic fbres) don’t run that risk. Also, they don’t rust, so they suit foreshore developments. KNOWLEDGE CENTRE ASK YOUR MATES THE HOT TOPICS OF DISCUSSION ON THE IPWEA ONLINE FORUMS. JOIN THE DISCUSSION NOW AT www.ipwea.org.au/askyourmates ALSO UP FOR DISCUSSION • Predicting road maintenance expenditure • Olympic pool fltration system • Standard drawings – grow your resource • Asset disposal policy and process • Private drainage infrastructure in parks • Gas pipe intrusion into stormwater • Mower transport between sites • Rehabilitation of sealed rural roads. # STREET SWEEPER ASSET LIFE PETER SMITH MANAGER ASSETS/PUBLIC SPACE, CITY OF HOLDFAST BAY, ASKS: We run 2 sweepers 7 days a week in a busy seaside area. Our asset plan has them due for replacement every 8 years. How do councils in similar environments treat the asset life of street sweepers? ROSS MOODY EXECUTIVE OFFICER, IPWEA NATIONAL, SAYS: While the seaside is an infuence, replacement should be based on age or utilisation, not age alone. The IPWEA National panel of feet managers’ benchmark is 8 yrs or 8000 engine hrs, whichever comes frst. If the sweepers work 7 days, chances are they do at least 1700 hrs/yr and will need replacement before 8 years. For more details see the IPWEA Plant & Vehicle Management Manual 3rd Edition.
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