Abstract: This invention relates to a self-propelling construction machine comprising a frame provided with at least two groups of ground engaging members disposed and spaced longitudinally on said frame, either the front or rear end of the frame being provided with means for coupling to a tractor or articulated vehicle. The group of ground engaging members disposed near the end with the coupling means comprises a device for adjusting their height with respect to the frame, enabling them to retract away from the ground when said machine is coupled to the tractor, whereas the ground engaging members other than those disposed near the end with the coupling means are constituted by a wheel assembly which is irremovable whilst the machine is functioning. One application of the present invention is the production of a travelling crane.