Title: Durability of SCC Concrete Structures in Switzerland

Author(s): J. Schlumpf

Publication: Symposium Paper

Volume: 212

Issue:

Appears on pages(s): 427-438

Keywords: durability of SCC; Gotthard base tunnel; long slump life SCC in hot condition; mix design of SCC; prequalification AlpTransit Gotthard; self-compacting concrete (SCC); slump flow; sulfate resistance of SCC; water permeability of SCC

DOI: 10.14359/12700

Date: 6/1/2003

Abstract:
Switzerland is a leading country in Europe regarding the use of Self Compacting Concrete. The current world's largest tunnelling project, the 56km Gotthard base tunnel, which is crossing the Alps from North to South, is designed for a service life of 100 years with only minor maintenance allowed during this period. SCC, as well as conventional concrete have been tested. On the basis of studies effected in 1998 at the TFB, and of the knowledge gained since 1998 with applications in practice, concrete mixtures for SCC were elaborated according to the AlpTransit prequalification specifications for the first time in 1999. The differences in the composition of the mixtures are principally the content of the < 0 .125 mm fines fraction and in the grading of the aggregate. Further differences are in the type and quantity of the high-performance plasticisers (Polycarboxvlate) and the water content in the concrete. On the basis of gained knowledge and past practical experience, it can be said that under the conditions as described here, water content for durable SCC mixtures should not exceed 180 l/m3. With the mixtures presented in this paper it is possible to manufacture SCC meeting the durability specications of AlpTransit Gotthard.