Categories
Tips & Tricks

Wind Speed

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.

The structural engineers at Cornell Engineers use the latest version of Australian Standard AS1170.2 to determine the wind speed for your structure.

Wind Classification to AS4055

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!

Categories
Tips & Tricks

Merry Christmas from the crew at Cornell Engineers

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

Categories
Concrete Tips & Tricks

Concrete Driveways and Paths

If you are after some definitive advice on the thickness of residential concrete driveways or what driveway slab reinforcement to use and how far apart crack control joints should be then you have come to the right place.

Check out this Residential Concrete Driveways and Paths manual produced by Cement Concrete and Aggregates Australia.

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.

The residential concrete driveway manual also has concrete driveway construction details including isolation joints and expansion joints.

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 and movement in your driveway.

Don’t forget local authorities (councils) have their own requirements for driveways, cross-overs and paths. For example, here is the link to the Driveway Technical Standards for Brisbane City Council:

We would love to design your driveway concrete for you. Please contact Cornell Engineers on 07 3102 2835.

If you have a cracked driveway slab, maybe we can help you. Call Matt Cornell for advice or to arrange an inspection.

Concrete Thickness for Commercial Driveways

Ask Cornell Engineers to design your commercial driveway. We’ll specify the concrete thickness, the strength of the concrete for your driveway.

Commercial concrete driveways are designed specifically for the weight of the vehicles using the driveway, the number of times a day a vehicle uses the driveway and the ground conditions under the driveway.

Contact Cornell Engineers for more information.

Concrete Driveway Repairs

Oh no. Your concrete driveway has cracks in it. Cracks in a concrete driveway aren’t necessarily a bad thing but if your concrete driveway is brand new and you have concerns, Cornell Engineers can check to ensure your concrete driveway was constructed correctly.

There are quite a few tools available to us for investigating cracks in concrete driveways. Some of these tools are:

  • Schmidt Hammer testing to determine the strength of the concrete surface. This is useful to determine if the concreter added too much water on site and weakened the concrete mix.
  • Slab coring. This is useful to determine if the concreter used a plastic membrane under the slab, the thickness of the slab and whether the steel reinforcement was chaired at the correct height in the concrete.
  • Crack plans. These plans record the location and width of surface cracking to allow an assessment of why the slab cracked.
  • Ground Penetrating Radar. GPR is useful to determine the location and type of concrete reinforcement that was used and also variations in the slab thickness.

Call us for a chat or Contact Us.

Categories
Tips & Tricks

Driveway Slab Reinforcement and membranes

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.

Does a Concrete Driveway need Black Plastic

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 – especially if your concreter wet the ground before pouring.

Got a structural engineering question? Ask us on the contact page or comment here!

Matt Cornell
Cornell Engineers

Categories
5 Questions

Five Questions with Craig Bullen

House Raise and Build in Under Project

Craig Bullen is the Owner/Manager of RE/MAX First Residential, Coorparoo.

Craig ran his own house raise project in Coorparoo which finished construction in 2013.

Craig Bullen Real Estate Executive
Craig Bullen

We caught up with Craig Bullen after his project finished and asked him 5 questions about his house raise and build in under renovation project.

Describe the scope of your project?

Full raise and rebuild of a Queenslander.

What is the best feature of your project?

Huge rear patio with Cathedral ceilings overlooking the yard and pool.

What simple lesson have you learned during this project?

Compromise is unavoidable.

Would you attempt a similar project again?

Yes, because by the 5th time I have done it I will know what I am doing… 🙂

How did Cornell Engineers add value to your project?

Matt came up with a great design for engineering and was available for solutions as problems arose. Very happy with the service.

Thanks Craig Bullen

Talk to Craig Bullen about real estate in Brisbane. Here’s his link: https://www.remax.com.au/agent-profile/41065

Thank you, Craig.

Want to Know More?

Planning a house raise and build in under project and want to know more?

We have some great resources for you right here on our website.

Check out this handy article:

https://www.cornellengineers.com.au/house-raise-and-build-under/