ABSTRACT

The paper discusses ultimate bearing capacity of spherical anchors in cohesionless soil under vertical pulling force. For that reason, several representative anchor diameter and embedment depth ratios were laboratory tested. The anchors were pulled out by given their vertical displacements, and the corresponding force intensity was measured. Regularities were observed in limit force increase with growing anchor depth and diameter, as well as the convergence of pulling force to certain limit value. The pulling force computations for the test cases were performed by Finite Elements Method (FEM). The problem was treated as an axial-symmetrical case. The vertical displacements of anchor are given in steps. Opening of cracks was modelled by exclusion of the elements subject to tensile stresses, thus providing a clear insight into the development of tension zones as the anchor displacement increased. The relationships between the anchor displacement and the pulling force as obtained by experiments and by numerical method have been statistically analyzed.