Predicting the elastic vertical working load response of friction pile groups embedded in cohesive soils is a problem still requiring a solution that can be easily implemented by practising engineers. A design procedure based on an extensive analysis of the results of a computer program is presented as a solution to the problem.The program was used to study the effects of the interaction of closely spaced piles in groups, on the pile group response to loading. It is possible to define an average pile stiffness (load per unit displacement) and discuss a reduction of this stiffness, due to pile interaction, when the pile is placed in a group of similar piles. This interaction is accounted for by a stiffness reduction factor, ρ.The design approach is compared with load tests at model and full scale, with good agreement. Key words: piles, pile groups, working loads, elastic pile displacements.
Modeling the lateral response of pile groups in cohesionless and cohesive soils