The paper deals with the field behaviour of an innovative kind of micropiles made with reinforced expanded polyurethane resin under both tension and compression external loads. To analyze the frictional resistance between the soil and the lateral surface of a single micropile and to determine the bearing capacity in different conditions, a series of field load tests were carried out in various sample sites. The paper explains how to build the micropiles and it describes the execution of field tests. On the basis of field tests, a method to evaluate the ultimate load has been defined. Moreover, the micropile-soil mechanical interaction has been modelled by applying a recently introduced analytical solution of the load-displacement behaviour.
