Scope of hydraulic operating device for gates which have long lifting height is increasing in order to make operating device of dam discharge facility downsize and reduce costs of it in these years. Those, in case of hydraulic motor type there are several pending problems, the cost of the hydraulic motor is expensive, and it is impossible to correspond to it with past maintenance technology. Using a hydraulic cylinder as drive source which have most results and reliability among hydraulic technology for hydraulic cylinder, we have invented and developed a rope hoist combined with advantage of both hydraulic type and electronic motor type.

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Embankment dams are often constructed on soft rock foundations in Japan, so it is important to precisely predict deformation of the foundations due to the fill placement at the design stage. For the accurate evaluation of settlement and strain of rock foundation surface during the construction, the influence of the scattering of the deformability of foundations on the deformation behavior should be investigated. In this paper, the evaluation method of settlement and strain of rock foundation surface during the construction was studied with stochastic deformation analysis changing coefficient of variation of the deformation modulus of dam foundation with a geological boundary. Based on the results of numerical study, the dam foundation design with the deterministic method which ensured the required reliability of the requirement was discussed.

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For the Sg. Kinta dam, which was the first RCC (roller compacted concrete) dam to be constructed in Malaysia, the RCC mix design was designed following RCD (roller compacted dam-concrete) method at the laboratory to arrive at the optimum mix proportions. The RCC design practice developed by USBR (US Bureau of Reclamation) and USCE (US Army Corps of Engineers) also reviewed. The trial mixing resulted in that RCC mix with a maximum aggregate size of 63 mm, was required less water when the proportion of fine aggregates in the mix was 36% and the fines content which was the percentage of the aggregate less than 75 μm size was 1.6%. The optimum mix were selected at the trial mixing and used in the construction of trial embankment to check on the in-situ properties and performance of the mixes. These field trials revealed that the fines content in the mix had to be increased to minimize tendency of the mix to segregate, to improve the compacted density of the RCC and impermeability of lift joint surface. We found that to minimize segregation, the proportion of fine aggregates and fines content needs to be increased to approximately 41% and 5.0% respectively.

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Dam-reservoir water interaction has significant effect on the dynamic responses of concrete dams, and accurate modeling of reservoir water is important in the earthquake response analysis of dams. In this paper, the performances of several finite elements for reservoir water are examined. The application of Perfectly Matched Layer to finite elements for reservoir water are developed to absorb reflecting waves at artificial boundaries, and the high performances are demonstrated by numerical examples.

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The destratification system was considered in ANEGAWA dam reservoir during the dam construction was exceeded, and facilities were installed later. Facilities began to operate and it was reported that they were able to be confirmed the effect. The measures showed an effect by operating the destratification system according to the prediction at first.

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