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Chen Q.,University of Sichuan | Duan B.,Hydrochina Kunming Engineering Corporation
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | Year: 2014

The gravelly clayey soils are commonly used as seepage resistant materials in high embankment dams. The core of the high embankment dam may crack owing to the layered construction placement or arch effect of the core. However, the filter design criteria for cracked gravelly clayey soils are not found. The filter tests are conducted using cracked gravelly clayey soils with different gravel contents and filters with different gradations and dry densities. The existing filter criteria for gravelly clayey soils are summarized and compared with the test results. The results show that the existing filter criteria cannot fully satisfy the need of filter design for cracked gravelly clayey soils. Based on the results of the tests and comparative analyses, the filter criteria for cracked gravelly clayey soils are proposed considering the combination seepage resistant mechanism of cracked gravelly clayey soils and the filters. The verification using the filter test results shows that the proposed filter criteria can be used for the filter design of cracked gravelly clayey soils with different gravel contents.

Xiang T.,CAS Wuhan Institute of Rock and Soil Mechanics | Xiang T.,Hydrochina Kunming Engineering Corporation | Feng X.,CAS Wuhan Institute of Rock and Soil Mechanics | Jiang Q.,CAS Wuhan Institute of Rock and Soil Mechanics | And 2 more authors.
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2011

On the basis of system analysis and summary of the existing research results of failure mode classification, analysis methods and controlling measures of surrounding rock for underground engineering, a new failure mode classification method for surrounding rock of large-scale underground cavern group is proposed. The special features such as large span, high sidewall and cross of multi-cavern influencing on failure modes have been concerned in the method. Based on the three levels: control factors, failure mechanism, generation conditions, 18 typical failure modes have been summarised. The corresponding stability analysis methods and control measures are recommended for each failure modes. Furthermore, a new method is also proposed for dynamic recognition of failure modes and the corresponding control measures according to dynamic updating of geological conditions and characters of surrounding rock revealed during excavation. The new methods have been applied to dynamic construction of Jinping II hydropower station. The potential failure modes and corresponding stability analysis methods as well as control measures on excavation and support design are recommended before the construction of powerhouse. During the excavation layer by layer, the failure modes, excavation and support strategies are calibrated, recognized and modified according to the revealed actual geological conditions and characters of surrounding rocks. The procedure is continued until complete of the construction. The practice indicates that the methods are applicable, scientific and systematic, so as to provide an effective way for excavation and support design optimization during construction and avoid occurrence of local instability problems.

Xie W.,North China Electrical Power University | Ji C.-M.,North China Electrical Power University | Yang Z.-J.,Hydrochina Kunming Engineering Corporation
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2011

To overcome the shortcomings of weak practicability of former short-term power generation scheduling rules, series of optimized scheduling processes are given in this paper by analyzing three typical years' daily runoff process of a cascade hydropower stations in Jinsha River and a large number of simulation daily runoff process through using POA algorithm in combination with GA algorithm. Based on these optimized scheduling processes, the scheduling period is divided into general period and dry-flood transition period. And then, the scheduling rules of a single hydropower station and a cascade hydropower stations during these two periods are also given. The rules can take full advantage of the rolling runoff forecast and carry out the rolling scheduling. Moreover, compared with the optimizing operation of scheduling rules, the maximum relative difference of the simulation results is no more than 1%. The effectiveness and practical applicability of the rules are testified by a case. Therefore, this paper provides a new perspective in formulating the rules of power generation dispatching.

Zhang Z.,Hydrochina Kunming Engineering Corporation
14th Asian Regional Conference on Soil Mechanics and Geotechnical Engineering | Year: 2011

The engineering practice of 200 m high concrete face rockfill dams in China is introduced in this paper. Innovative ideas and techniques involved in engineering design, construction and operation are highlighted during construction of four 200 m high dams, i.e. Tianshengqiao 1st cascade, Hongjiadu hydropower project, Sanbanxi hydropower project and Shuibuya hydropower project. Key issues and countermeasures in the development of super-high dam are addressed including section zonings, design of rockfill materials, deformation control and seepage control.

Luo Y.,Hydrochina Kunming Engineering Corporation
Shuikexue Jinzhan/Advances in Water Science | Year: 2015

The research methods of hydraulics are diverse and each method has its characteristics. It is more concerned for the similarities and differences of reached achievements from all kinds of methods. Based on the bottom outlet of flood discharge with high water head in one hydropower station, the simulation and observation are carried through for the hydraulic issues by applying the physical modeling experiment, the prototype measurement of hydraulics and the time-averaged turbulence mathematical model. The adaptable scope and degree of three kinds of methods are identified. It is identical well for the simulated results of three methods with the macroscopic hydraulic flow state, bottom flow velocity, time-averaged pressure and aerated cavity. Meanwhile, there is a certain difference in the simulation of flow profile. The fluctuation prototypical water surface and longitudinal diffusion of water jets are larger. The achievement can be used to lead the selection of research method and correction of achievement for this type of hydraulic issues. ©, 2015, China Water Power Press. All right reserved.

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