The effect of design on interaction of foundation slabs with the base

Grounds and foundations, underground structures

The paper suggests advanced trend in reduction of materials consumption for the base slabs owing to their design. As an example, the stress and strain state of the models of solid slabs and slabs with controlled forces interacting with sand base, are addressed in the paper. The models were loaded by static system of concentrated vertical forces. Stress and strain state of the models was assessed by the results of laboratory tray experiments with strain measurement and by the data of numeric calculations by finite element method with application of Coulomb-Mohr soil model. Based on the comparison of obtained results, it is demonstrated that the slab with controlled forces has advantages over a solid slab. For example, owing to the control of forces, it becomes possible to avoid alternation in bending moments diagram, flatten the values of support bending moments for intermediate supports and achieve more smooth deflection of the slab, thus creating prerequisites for significant reduction of materials consumption. Apart from this, it was established that experimental values of bending moments and slab deflection are qualitatively consistent with numerical prediction, while the finite element calculation gives slightly inflated absolute values as compared to the experiment results. The results of the studies may appear useful in the design of base slabs for supports of overhead roads, trestlework along with industrial civil buildings and frame type structures with regular grids of columns.