Title:
Slab-on-Ground Analysis for Storage Rack Concentrated Uplift Loading
Author(s):
Nathan Bissonnette
Publication:
Structural Journal
Volume:
122
Issue:
6
Appears on pages(s):
101-112
Keywords:
model concrete; seismic uplift; slab-on-ground (S.O.G.); storage racks
DOI:
10.14359/51746820
Date:
9/1/2025
Abstract:
Slabs-on-ground supporting storage racks are often subjected to concentrated uplift under building code seismic forces. While methods for determining slab-on-ground capacity for downward loads are well-defined, guidance for resistance to uplift has been limited and relies on finite element analysis. A simplified approach is presented for calculating slab-on-ground uplift capacity as a function of slab thickness, reinforcement content, and storage rack frame depth. Testing is conducted on small-scale concrete samples in bending to obtain the material properties. Model slabs are created and tested for an upward and downward force couple representing concentrated seismic uplift on a reinforced slab-on-ground. The plastic hinge failure mechanism of the slab samples is correlated with finite element models, and straightforward formulas are developed to produce a table of uplift capacities for common storage rack and slab-on-ground configurations.
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