Design of No.20 Dam Section in Lingjintan Hydropower Station

The No 20 dam section as described in this paper is situated between the spillway section and the powerhouse section, where a poor geological condition was revealed during excavation and the structural design was complicated. In order to ensure the powerhouse construction during flood season in 1997, the design of this dam section was largely modified. This paper outlines the design of this dam section, including handling measures, joint grouting, calculation and analysis by means of three-dimensional finite element method. The practical operation has justified the success of the dam section design, which has ensured both the power generation on schedule and satisfied the requirements for the safe and reliable operation of the project.