A compression body is inserted into the contraction joint between two tunnel lining elements, which body deforms in response to a compressive load caused by the tunnel lining elements moving towards each other. The compression body is composed of a material containing voids, and has a compressive strength of at least 1 MPa and a void fraction of between 10% and 90% of its total volume. The compression body may be composed, for example, of steel foam, or of a mixture which contains cement and blown-glass particles or plastic particles.When a predetermined compressive load is exceeded, the voids within the compression body collapse in a stepwise manner, or are compressed in a stepwise manner.