<p>The invention relates to a seal for pipes to be driven in the ground. The essential feature of this invention is that the seal (3), consisting of rubber or material similar to rubber, has grooved slots (4, 5) on both sides and can be activated by means of a medium which can be injected and increases the total volume, the cavity (7) which is initially available for this medium being small in comparison with the total volume of the seal in the non-activated state. <IMAGE></p>
