Problematik der Bestimmung der Vortriebsklassen beim Spritzbetonverfahren im Tunnelbau

摘要

The article deals with the determination of the payment principles for the works to be performed by the contractor before and during the construction of a tunnel. Since excavation and securing of the subsoil cause most of the total costs incurring and since deviations of the predicted ground conditions are ― according to Central European law ― risk factors to be coped with by the client, the claim potential is particularly high. When applying the shotcrete tunnelling method the selection and interpretation of the soil exploration measures, the necessary professional handling and assessment of the subsoil behaviour during the tunnel construction process, as well as the dimensioning of the final lining which is based on the experience gained during the construction of the tunnel, affect the time and costs of construction to a considerable degree. Based on these facts the possibilities and limits of contracts are depicted and discussed.