Uplift Pressure below Horizontal Apron with Cutoff at Intermediate Points, Founded on Anisotropic Pervious Medium of Finite Depth

The two essential factors to be considered in the designing of the aprons of Hydraulic structures are (i) uplift pressures and (ii) exit gradient. In this country. Khosla’s curves still form the basis for determmation of uplift pressure below the weir floor and exit gradient at the toe. However his work is based on the assumption that the apron is founded on anisotropic pervious medium of infinite depth. The present investigation takes into account the effect of (i) anisotropy, and (ii) the finite depth of the medium, for the case of an apron having cutoff at intermediate points. The electrical analogy method has been used to determine the uplift pressures. Theoretical analysis, based on the lines of Pavlovsky’s original solution, has also been given, taking into account anisotropy of soil medium. It is found that the experimental results are very close to the theoretically calculated values. Design curves are also presented for finding uplift pressures at some key points.