Buildings in Australia are designed to resist wind forces by complying with Australian Standards. The “design gust wind speed” for a particular site is determined by considering the height of the building, the location of other buildings and topography on all sides of the building. Houses in exposed locations or on tops of hills are designed for higher wind speeds and consequently higher forces than buildings in built-up areas.
We use the latest version of Australian Standard AS1170.2 to determine the wind speed for your structure. Where the building complies with AS4055, we can classify the wind speed using that standard too.
Call us for a wind assessment for your building today!
On behalf of Jess and Kim, I’d like to wish our clients, friends and associates a very Merry Christmas and Happy New Year. Our office is closed now until 13 January. Have a safe holiday season and we look forward to helping you again in 2014. Matt Cornell
At Cornell Engineers we have been referring to this document since its release in 2006 and it’s still the best way to ensure satisfactory performance of your driveway slab. Remember that in the absence of better information, this is the manual that will be referred to in the event of a dispute about uncontrolled cracks in your driveway.
Steel reinforcing mesh is used in driveway slabs to control the width and length of cracks in concrete. If the mesh is “walked in” or placed at the bottom of the concrete slab, it is ineffective and won’t control cracks. Ensure your mesh is correctly positioned when pouring by chairing it on bar chairs at 1000 x 1000 centres.
I was also asked recently if driveway slabs need the black plastic membrane (200 micron polyethylene membrane) under them before pouring. If you have the plastic on site, then I recommend using it. The purpose it serves is to prevent the dry ground sucking moisture out of the wet concrete. That moisture is needed by the cement powder in the chemical reaction called hydration. Don’t worry if your driveway slab has already been poured without the plastic membrane. Not having it won’t decrease your slab’s strength too much.
Got a structural engineering question? Ask us on the contact page or comment here!