Concrete in aggressive ground

Abstract

BRE publishes guidance on concrete in sulphate-bearing ground and groundwater in the form of BRE digests. A new edition of Special Digest 1 (SD1), first published in 2001 with a revised edition in 2003, was published in 2005 following the completion of a four-year programme of research on the thaumasite form of sulphate attack (TSA). TSA was first identified on high-quality concrete foundations on bridges on the M5 motorway in the UK. Thaumasite results from the reaction of sulfates with the calcium silicate phase of Portland cement. SD1:2005 deals with the specification of concrete for buildings and civil engineering construction in contact with aggressive ground in the UK. The six parts of SD1 have the following titles: introduction, chemical attack on conaete, assessing the aggressive chemical environment, specifying concrete for general cast-in-situ use, specifying surface-carbonated precast concrete for general use in the ground, and design guides for specific precast concrete products. The key changes between the 2003 and 2005 editions are explained. The relationship between SD1:2005 and BS and EN standards is outlined.