In view of the current problems such as less research on the combined support of anchor cable and frame lattice beam in slope reinforcement, the actual project of slope support on the left bank of a hydropower station was taken as the background. The stability of the original slope was analyzed by combining the limit equilibrium method and the finite element strength reduction method. The combined support scheme of anchor cables and frame lattice beams was studied. It mainly included anchor cable anchoring force calculation, anchor cable arrangement spacing, anchor cable length, optimal incidence anchoring angle and frame lattice beam size, etc. Finally, the support effect was studied by combining with numerical simulation. The results show that the original slope needs to be reinforced and supported. The error of the original slope safety coefficient obtained by the finite element strength reduction method is less than 1.5%-2.0% with the limit equilibrium method. The temperature loading method was used to simulate anchor cable prestressing for stability analysis of slope with combined support of anchor cable and frame lattice beams, and the combined support is effective and no obvious slip crack surface appears after the support. The study can provide reference for similar slope support projects.

In order to evaluate the water use efficiency of the central Yunnan urban agglomeration accurately, 14 indicators were selected from five aspects of comprehensive, industrial, agricultural, living and ecological water use, and the evaluation index system was constructed. The subjective weights were obtained by analytic hierarchy process. The entropy weight method was used to determine objective weights. The game theory method was adopted to get the combination weight. The TOPSIS evaluation model was established to calculate the relative closeness degree of water use efficiency and the closeness degree of each criterion layer in central Yunnan urban agglomeration from 2011 to 2020, and the national average data was added to the evaluation sample as the criterion for judging the results. The results show that in terms of spatial distribution, Kunming has the highest water use efficiency, followed by Qujing and Yuxi, both of which are at a good level, and Honghe and Chuxiong have the lowest water use efficiency, both of which are lower than the national average water use efficiency, at a poor level; In terms of time series, except for Qujing City, the overall water use efficiency shows an upward trend. Qujing City shows a downward trend before 2016 and slowly recovers in 2016. By analyzing the causes of the changes, this paper put forward the shortcomings of water use efficiency in each city, which can provide reference for improving water use structure and water use efficiency in central Yunnan urban agglomeration.

The dynamic changes of the water ecological footprint and carrying capacity of the representative cities along the first Phase Project of South-to-North Water Diversion East Route Project from 2010 to 2020 were analyzed based on the water ecological footprint and carrying capacity model. The SVR model was used to predict the water ecological condition of these cities from 2021 to 2025. The results show that the per capita water ecological footprint of Shandong displays a general uptrend, and the per capita water ecological footprint of the south section of Luoma Lake and Jiaodong Peninsula is at a high level. The per capita water ecological carrying capacity in the north of Luoma Lake and Jiaodong Peninsula shows an upward trend, while in the south of Luoma Lake and across the Yellow River, it shows a downward trend, among which the south of Luoma Lake is at a high level. The water ecological deficit or surplus of the representative cities along the line began to improve in 2013, indicating that the implementation of the project has a positive effect on the improvement of ecological environment. From 2021 to 2025, the water ecological footprint of Jiangsu section will increase and the water ecological carrying capacity will decrease. With the continuous increase of water consumption in various industries, the sustainable development of this region will face a great threat. Although the water ecological situation in Shandong section is developing well, it will continue to be in a state of water ecological deficit for a period of time, and the situation of water ecological pressure is severe.

Due to the long-term operation in the low-load area, the hydropower unit deviates from the optimal operation area, resulting in large vibration of the unit, poor flow state of water flow, and other adverse consequences, such as cracks in runner blades and serious cavitation of the unit. In view of the complex flow conditions in the draft tube, this paper proposes two improvement schemes. Based on RANS equation, the standard SST κ-ω turbulence model is adopted to calculate the steady and unsteady solutions for three operating conditions of 0.45P_r(P_r is rated output), 0.60P_r, and 0.75P_r. The results show that the installation of the guiding device can effectively reduce the eccentric vortex band of the draft tube, and greatly reduce the pressure pulsation amplitude, so as to reduce the vibration of the unit. Considering the streamline of draft tube, vortex zone of draft pipe, turbine efficiency and pressure pulsation amplitude, especially the importance of pressure pulsation intensity to the stable operation of the turbine, it is concluded that the symmetrical arrangement of two diversion plates at the inlet of the draft tube has the better improvement effect on the Francis turbine. The results provide a certain theoretical basis for the safe operation of the hydraulic turbine unit under low load.

Since the mechanical properties of dam materials can directly affect the settlement deformation and structural stability of core wall DAMS, it is necessary to explore the mechanical properties of soil-rock mixture and the internal deformation and failure mechanism by means of macro and micro in order. Taking the Rumei Hydropower Station in Tibet in Lancang River as research background, particle flow code (PFC) method based on discrete element was used to carry out large-scale triaxial numerical simulation test. The results show that with irregular enhancement in the form of block stone, the stress peak nodes was in advance, peak strength increased obviously with significant softening characteristics, shear shrinkage was not obvious, and the dilatancy is prominent; The shear zone evolved from a single “工” shape to a complex “工” shape. The thickness increases from 45 mm to 105 mm, and the final swelling failure area increases exponentially to 35 000 mm². The extreme value and the number of force chain strength increased. Increasing the stone content was the key to improve the peak strength of the sample. When the rock content was low, the shear shrinkage characteristic was prominent, and the dilatancy characteristic was not obvious. With the increase of the stone content, the “gear” effect of the block stone was enhanced, and the shear zone failure mode was transitioned from smooth reverse “S” shape to multiple irregular shear zones, with the thickness increasing from 47.5 mm to 105 mm, the swelling failure area evolving from 12 800 to 35 000 mm², and the number of strong chains increased. The extreme strength of the force chain was increased from 10.49 kN to 164.30 kN. In conclusion, it is suggested to select blocks with high irregularity and increase the stone content to enhance the structural strength stability. The research can provide reference for the stability evaluation of the project in the later stage and the work of the proposed dam.

When the diffusion angle of each side of the wing wall in the gate is 12°, the horizontal distribution of outlet velocity of single-stage stilling basin is easy to be uneven in the medium and low water level period. To solve this problem, based on the physical model test, the law of horizontal distribution of outlet velocity of two-stage stilling basin was studied. The results show that with the decrease of downstream water level, the outlet velocity at the left and right banks of the second stage stilling basin changes in four stages: decrease- increase-decrease-increase, and the initial water level and water level range of each stage were closely related to the Fr. The smaller the incoming flow Fr is, the stronger the horizontal diffusion ability of hydraulic jump in the second stage stilling basin is, and it will be less disturbed by the backflow on both sides of the first stage stilling basin. The range of water level in the second stage will be larger, and it is more suitable for the medium and low water levels. The closer the downstream water level is to the end water level of the second stage, the greater the outlet velocity at both sides of the second stage stilling basin is, and the horizontal distribution of outlet velocity is more uniform. When the incoming flow Fr is the same, the regulating effect of the second stage stilling basin is more significant at low water level, and the energy dissipation rate is greater. The results can be used as a reference for the design of energy dissipation facilities under the gate and the operation management of the gate.

Long distance and concealment of underground cable in hydropower station result in difficulties in cable fault location. Due to the simple wiring, the impulse high-voltage flashover method is commonly used to locate cable faults, which needs technicians with rich waveform analysis experience to locate fault accurately. For the above situation, by studying the fault positioning principle and waveform analysis method of impact high voltage flashover, a cable fault location technology based on traveling wave cross-correlation method was proposed. The simulation analysis results show that the proposed method can effectively realize automatic cable fault location. Finally, the analysis steps and procedures of power cable fault location has been practiced in Houziyan Power Generation in Dadu River and realized high-precision positioning of 10 kV cable fault point, which reduced the cable fault locating workload and working hours while improving the efficiency of cable fault location.

The vertical slit fishway has the capacity to better cope with the fluctuation of water level in both upper and lower sections and favorable water flow conditions. Three schemes were designed for the shape of the fishway tank chamber of a certain project fishway. The physical models verified with a 1∶5 scales were used to investigate the impact of the tank chamber's structure on the flow pattern, maximum flow velocity, and hydraulic properties of mainstream region under different size and type of baffle and guide plates. This was done through numerical simulation calculation. They performed a test of the physical model on the optimal shape with scale of 1∶5. The physical model of the overall with scale 1∶20 was used to analyze the maximum velocity along the water depth and the vertical slit, and the diversion flow of the fishway under different water depth conditions was proposed, providing reference and reference for similar projects.

Xiangjiaba Hydropower Station has six functions: power generation, navigation, flood control, irrigation, reverse regulation, sediment retaining. Since the project was put into operation in 2012, all other benefits except irrigation have begun to show gradually. With the completion of the first water intaking tunnel project of the north and south main canal of Xiangjiaba, and the comprehensive construction of the first phase project of the north general irrigation area, the research on the impact of irrigation water intaking on the power generation of Xiangjiaba hydropower station is an urgent work. Based on the adjustment calculation of 43 years series runoff during 1970-2013, inflow variation of Xiangjiaba hydropower station was calculated by considering the impact of the six large reservoirs regulation and storage in the upstream and water diversion in the Yunnan province. On this basis, the impact of water intaking after the first phase of north irrigation area, north second phase of irrigation area, and irrigation district being completed on the power generation of the Xiangjiaba Hydropower Station was analyzed. The research shows that irrigation water intaking reduces the power generation of Xiangjiaba, which is 1.78×10⁸ kW·h, 2.84×10⁸ kW·h and 3.78×10⁸ kW·h, respectively, compared with that before water intaking, and mainly in the dry season. After the intake of water in each period, the water discharge can be reduced by 109 m³/s at most, the annual average output can be reduced by 105 MW at most, and the number of installed hours can be reduced by 63 h at most.

In order to research the growth adaptability and engineering applicability plants in the floodplain ecological restoration area in the lower reaches of the Three Gorges dam area under flooded environment, four kinds of shrub plants such as distylium chinense, myricaria laxiflora, salix variegata and rosa sp were planted and observed in the floodplain area at the same water level in the lower reaches of the Three Gorges dam area. Four shrub plants experienced a certain degree of flooding period. The results show that the survival rates of the four shrub plants were different under flooding conditions, and the plant preservation rates from high to low were as follows: salix variegata, distylium chinense, myricaria laxiflora and rosa sp. The morphological changes, plant height growth and recovery growth were observed. Among them, salix variegata, distylium chinense and myricaria laxiflora showed better flooding adaptability under flooding stress. The applicability of ecological restoration engineering of 4 Shrub plants was evaluated by weighted scoring method. The scores from high to low are distylium chinense, myricaria laxiflora, rosa sp and myricaria laxiflora. It is determined that distylium chinense can be used as the main shrub plant in the floodplain ecological restoration project.