I'm a structural engineer and YouTuber who loves to talk about building, construction, and engineering. Subscribe to my newsletter for easy-to-read tips and insights!
The tiny wall that tricked the slab model
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A small nib wall can make your slab model look much better than it really is. In one suspended slab model, the deflection was around 6 mm with the nib wall included. But as soon as the nib wall was removed, the deflection jumped to around 20 mm. Same slab. Same loads. So what happened? The software thought the nib wall was helping to hold the slab up. Because of that, the slab was getting extra restraint at that location. But was it actually? That is the important question. The danger is not the software. The danger is believing the model without asking: “Will this actually behave like that on site?” A short nib wall may exist on the architectural plan. But that does not always mean it can act as a reliable structural support. Ask yourself: Can that nib wall actually take the reaction? Is it reinforced concrete or masonry? Is it connected properly? Does it continue down to proper support? Sometimes removing the wall from the model gives a worse result. But it may also give a more realistic result. And in engineering, realistic beats pretty every time. PS: Next week inside BengLab, we’re hosting a live webinar with the Inducta team on suspended concrete slab modelling and design for beginners. If you’re already in, I’ll see you there. If you’re not, you can join us here: https://www.skool.com/benglab/about Cheers, |
BEng Gabriel
I'm a structural engineer and YouTuber who loves to talk about building, construction, and engineering. Subscribe to my newsletter for easy-to-read tips and insights!
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