Design of RCC gravity dam of Mianhuatan Hydropower Station

The Mianhuatan RCC gravity dam has its maximum dam height of 111 m and the crest length of 308.5 m. It is divided into seven dam sections, among which No.1 and No.2 sections are the left bank non overflow dam, No.5, No.6 and No.7 sections the right bank non overflow dam, and No.3 and No.4 sections the overflow dam. In the design, the shear strength of dam foundation surface and bedding surface, the stability against sliding of the foundation of different dam sections, and the safe coefficient of stability against sliding of non overflow dam all meet the requirements of the specifications. Under the combination conditions of various basic loads, the stress distribution of different dam sections is safe. By reference to the project practices at home and abroad, the Mianhuatan gravity dam only adopts transverse joints with the distance of 33 64 m but no longitudinal joint. In the seepage control, the second grade RCC seepage control measures have been taken. Meanwhile the strict temperature control measures have been adopted in the construction to guarantee the quality of the RCC dam.