the drive shield 10 and where the latter is composed of individual drive members the rams 15 would connect with the frame thereof as the shield 10 advances in the course of the driving work the member 13 can be drawn up with the aid of the rams 15 either continuously or intermittently the tubular member or inner shuttering 12 can likewise be connected with the shield 10 or its frame with the aid of additional double acting hydraulic rams 16 which enables this component to be drawn up to follow the progress as well it is however possible to utilize transferable or transposable means such as a series of tubular members arranged end to end to constitute the inner shuttering 12 and in this case the rams 16 are omitted and there is then no connection established between the shuttering 12 and the shield 10 during operation it is desirable to produce the lining 11 progressively in accordance with the driving progress and as the member 13 is drawn up with the rams 15 concrete is pumped into the reception space continuously or intermittently in the latter case the member 13 is advanced in incremental stages each corresponding to the length of one concrete section once the preceding concrete section has become self supporting this means that its member 13 must be held in a stationary position for some time until the corresponding concrete section has been created fig2 depicts by way of example an array.