Ground movements in soft cohesive soils impose lateral pressure on piles. Among others, here the magnitude of pressure depends on the amount and speed of ground movement, the pile’s bending stiffness and the geometrical boundary conditions. In recent decades, considerable effort has been devoted by many researchers to study the problem of lateral pressure on piles in soft cohesive soils, experimentally and using numerical methods. Unfortunately, these investigations have led, for example, to highly divergent calculation approaches, e.g. pile group factors. In classical Lagrangian Finite Element Method, large soil displacements distort the finite element mesh which might lead to inaccurate results or the numerical analysis does not converge to a stable solution. Therefore, most numerical based research on lateral loads was done for moderate soil displacements. Numerical investigations of the problem are more challenging when large deformation respectively is involved. In continuum-based models, the traditional description of kinematics is either based on Lagrangian or Eulerian approach where each has its own advantages and disadvantages. Coupling the two descriptions in one approach by exploiting the best features of each is therefore desirable. One coupling approach, called the Material Point Method (MPM) will be explained in brief. The potential of the method is shown with respect to the results of a small-scale test on a single pile in soft clay. Furthermore, numerically calculated lateral pressure and group effects will be discussed.
Subjects: None provided
Author: Johannes Aschrafi, Shreyas Giridharan and Christian Moormann, Univ. Prof. Dr.-Ing.
Publisher: DFI, EFFC