Study on stress and deformation and engineering measures for concrete faced rockfill dam built in narrow valley

In order to study the impacts of topography of river valley on the stress and deformation properties of concrete faced rockfill dam (CFRD), an ideal 3D finite element model was used for stress and deformation analysis. Based on the studies and the analysis of a real CFRD project, engineering measures for improving the stress and deformation status of CFRD built in narrow valley are proposed. Research results reveal that the main effects of river valley on CFRD are the restraint and supporting action of abutments on dam body and concrete face slabs, and this effect will be reduced with the increase of the valley shape factor, i.e. the ratio of crest length to the height of the dam. For CFRD built in a narrow valley, the displacement gradient of rockfill and the compressive stress of face slabs are relatively large. Engineering measures such as increasing the compaction density of rockfill, setting up the transition rockfill zone with increased modulus, reasonably determining the timing for face slab construction, and arranging filling material with the capacity to absorb the deformation of face slabs in vertical joints of the slabs, can be taken to improve the stress and deformation status of the dam and the face slab. © 2022 China Water Power Press. All rights reserved.