The Past
A century ago, Westergaard gave engineers a first-of-its-kind solution for analyzing a loaded concrete slab resting on soil. His work was applied to highways, airfields, and industrial floors around the world.
Over the decades, design in the road and airfield markets evolved dramatically. 20 years ago, highway concrete pavement design models could already simulate cracking, faulting, roughness, climate effects, traffic spectra, and soil behavior hour-by-hour over decades of service life.
Meanwhile, the industrial slab-on-ground market led the industry in innovation — introducing laser screeds, F numbers, early entry saws, pan floats, and plate dowels. ACI 360R-10, "Guide to Design of Slabs-on-Ground," recognizes many slab types not used in roadwway or airfield design — a testament to the creativity in this space.
Current Practice
Despite the innovations in the slab market, slab-on-ground thickness design methods remain largely anchored to 1920s Westergaard theory.
As ACI 360R-10 states:
"Because the three commonly used slab thickness design methods (PCA, WRI, and COE) all are based on Westergaard's work and the assumption that slabs are always fully supported by the subgrade, they give erroneous results for slab thickness."
"The PCA and WRI methods only address live loads imposed on the slab's interior..."
Yes, the three most common design methods gives erroneous results and usually ignore the joints.
Real slabs curl.
Real slabs lose support.
Real slabs have joints.
And joints are not minor details — they are structural discontinuities that govern performance.
Better Designs...Today
Thankfully, ACI 360R-10 provides the path forward:
"The finite-element method can be used to analyze slabs-on-ground, particularly those with discontinuities."
That is exactly what The Slab Designer does. Well, it does much more than that, but that is a big part of what it does.
The Slab Designer exists to bring slab-on-ground design into the modern modeling era.
Contact
To be considered in our launch group, contact:
access@theslabdesigner.com
All other inquiries, please contact:
info@theslabdesigner.com