Elastomer seal arrangements between segments of tubular tunnel

摘要

An arrangement (6) for sealing longitudinal and lateral gaps between two adjacent concrete, steel or reinforced concrete segments (2',2'') forming a tubular tunnel includes a profiled elastomer seal (8) which is housed in a recess (7) along the edges of each segment. The seal (8) has grooves on the surface facing the recess (7) and also internal channels. On the back face of each seal (8) is an open channel holding an emergency seal (9) which expands on contact with water and hence seals between opposing seals (8) if segments (2',2'') move excessively. Pref. the back of the profiled seal (8) may have either a single open channel on the centre line or two open channels symmetrically located on both sides of the centre line. Further closed channels may be included on both sides of a single open channel or between two open channels. Additional closed channels can be included between the open channel base and the base of the profiled seal. The flanks of the open channels can be a) arched into the channel base to give a circular cross-section with a hopper-like entry; b) concave and running into a flat base or c) conical with the narrow part at the channel base. Noses in the open channel prevent the emergency seal (9) falling out. Emergency seals (9) are strips with a rectangular or trapezium cross-section or a circular cross-section card, and may either occupy part of the open channel or completely fill it. Emergency seals (9) are placed in the open channel immediately before joining adjacent segments (2',2'').