Extension of the Gravity Method for 3D Cracking Analysis of Spillway Piers Including Uplift Pressures

Abstract

The classical structural stability evaluation of concrete hydraulic structures, such as spillways, is based on the application of rigid body equilibrium to compute force and moment resultants, and in most instances beam theory assuming linear stress distribution. The computations are done supposing a symmetric structure subjected to load acting in the upstream/downstream direction leading to a unidimensional axial force (P) -bending moment (M) interaction problem. However, several load conditions (ice floes, earthquakes) could apply transverse force components leading to a nonlinear biaxial flexural problem (P- Mx - My ) taking into account the potential cracking of the sections, as well as pressurized water penetration in cracks. A three-dimensional extension of the gravity method is presented herein for arbitrary sections such as those of spillway piers. Robust algorithms based on the strength of materials have been developed to compute the kernel of arbitrary sections, locate the neutral axis (NA), and...