Plastic-damage analysis of concrete cutoff wall for a concrete face rockfill dam

Through in situ measurement records and numerical analysis, this work investigated the behaviour of a concrete cutoff wall for a concrete face rockfill dam built on an alluvium foundation. Monitoring records were obtained from a detailed monitoring system. A three-dimensional numerical model that uses a plastic-damage model for the stress–strain relationship of concrete was developed to predict the behaviour of the concrete cutoff wall. A coupled hydro-mechanical (HM) method was adopted to characterise the HM coupling effect of the dam and the alluvium foundation. The dam construction and the subsequent reservoir-filling processes were simulated in the numerical model. The results were compared with in situ measurements to validate the numerical model. The loading mechanism, stress and deformation behaviour, damage distribution and cracking of the cutoff wall were analysed. The wall behaviour, especially with relevance to the walls for dams with corewalls or inclined corewalls, and the effects of several factors on wall behaviour were investigated.