Causes of and Responsibilities for an Excessive Amount of Leaking Cracks in a Massive Concrete Mat Foundation

Abstract

Integral watertight concrete structures can be an effective and durable solution for underground facilities. The paper presents an evaluation of the major causes of and responsibilities for wide through cracks in a large mat foundation. A large number of leaking cracks with a width of up to .8 mm were observed in the mat foundation. Considering the importance of water leaking through the cracks in terms of the serviceability and durability of watertight concrete structures, emphasis is placed on the effect of early-age temperature rise in mat foundation. Mitigation strategies to prevent the formation and propagation of early-age through cracks are discussed. The concrete technology methods are aimed at reducing the concrete temperature by using low-heat generating concrete. In general, when assessing the risk of early-age cracking, drying and autogenous shrinkage may be ignored. The role of cement type, concrete cover and reinforcement to limit the width of cracks was analyzed.