Abstract: An improved joint for pile sections which have a nut at the ends, fastened such that one of its end surfaces is in the same plane as the end surface of the pile section. The joint being effected by a threaded bolt which engages with the nuts on two cooperating pile sections. The nut is provided with an annular groove having radially-directed locking notches in the bottom. A locking disk is inserted into the groove. The disk has resilient locking tongues with radial edges which are directed against the unscrewing direction and which engage with the notches in the nut.