Abstract: Cracking of face slabs of a concrete faced rockfill dam is one of the key factors affecting its safety and performance. Based on the ABAQUS software, this study carries out secondary development to simulate the long-term deformation of rockfill material and the hydration heat of concrete, imposing a boundary of temperature varying in space and time. We examine the joint action mechanism of continuously increasing in the long-term deformation of rockfill body and spatiotemporal variations in environmental temperature, combining with a case study of a concrete faced rockfill dam in Laos. The main cause of a large number of early horizontal cracks on the panel is revealed－excessive along-slope tensile stress in the panel surface layer that is caused by temperature rising due to concrete hydration heat and by ambient temperature changes in early time after concrete casting. Results show that the tensile stress calculated in the condition of temperature change is higher than that under constant temperature. Thus, this study suggests an important perspective for selecting slab concrete casting timing and controlling temperature cracks or deformation cracks.

Key words: concrete faced rockfill dam, long-term deformation, temperature field, the finite element method, secondary development