Dissolution of No‐Fines Concrete Slab due to Soft‐Water Attack

Abstract

A case history is presented of a no‐fines concrete subgrade slab through which soft waters had been percolating for several years. The slab was intended to act as a drainage layer, but elements of the drainage system became blocked due to calcium‐based deposits after a relatively short period in service. The paper presents the results of water and solid‐deposit analyses that were carried out, and discusses the mechanism of deposition and blockage of the drainage system. The rates of dissolution of the slab and the potential for continued blockage of the drainage pipes are also examined. Remedial measures based on these assessments were adopted. The case serves as a useful example of the importance of proper understanding of materials technology in civil engineering construction.