Snap-through cracking of desiccating plastic concrete slabs, which is occasionally observed in practice, can reduce significantly the service life of concrete structures. However, its underlying mechanism has remained largely unexplained, with very limited literature available. In this paper, theoretical analyses…
Snap-through cracking of desiccating plastic concrete slabs, which is occasionally observed in practice, can reduce significantly the service life of concrete structures. However, its underlying mechanism has remained largely unexplained, with very limited literature available. In this paper, theoretical analyses of snap-through cracking in plastic concrete slabs, which are based on combined geotechnical engineering and fracture mechanics models, are presented. The results obtained capture the essential features of snap-through cracking, showing how surface cracks in plastic concrete can become unstable, deepen rapidly, and either be- come stable again or propagate through the full depth of the slab. They also clarify the roles and significance of pre-existing surface cracks and surface defects, pore moisture suction, and the depth of desiccation in this process. Most importantly, they also confirm the critical role of good construction practices, including the control of compaction and desiccation, in preventing this form of cracking.