Load transfer method for the calculation of foundations and soil reinforcement systems with rigid columns

The load transfer method (LTM) is an appropriate method for the calculation of systems with rigid columns and piles with relatively simple geometry. It consists in a practical engineering tool with simple diagrams representing the main interactions and results for the soil-column system. The soil above, between and below the columns is described by its constrained modulus. The deformation-dependent soil-column interaction for skin friction and tip resistance is defined with load transfer curves. Non-linear load transfer curves based on in-strumented load tests are recommended in order to represent the real behavior in an optimal way. Load transfer curves are proposed for a larger international use, as an alternative to the well-proven Frank and Zhao (1982) curves based on the pressuremeter modulus and used mainly in France. The load transfer method, which has been originally developed for single columns (piles), is extended for combined systems with columns in wide grids or under footings.