In order to alleviate the water shortage in the development of oil and gas resources, horizontal wells are often used to exploit groundwater resources, but there is little analysis on the factors affecting the water intake of horizontal wells. Therefore, the numerical model is used to simulate the horizontal well mining mode and explore the influence of horizontal well layout direction, burial depth, pipe length and well pipe permeability on the water intake effect. The results show that considering the water intake efficiency and construction difficulty, the optimal horizontal well layout direction should be laid along the incoming water direction, and the location should be located in the upper layer of Luohe Formation as far as possible. The recommended pipe length and well pipe permeability are 800 m-1 000 m and 0.15, respectively, and the corresponding production volume is 1 368 m³/d-2 389 m³/d. The research results have important guiding significance for alleviating the shortage of water resources in the development of oil and gas resources in the eastern region of Longdong and formulating reasonable development strategies of water resources.

In order to improve the accuracy and reliability of runoff prediction, the advantages of EMD in dealing with non-stationary time series are introduced, and a BP neural network prediction model based improved adaptive noise complete set empirical mode decomposition (ICEEMDAN) and whale algorithm (WOA) optimization is established. Taking the inflow runoff prediction of Jinpen Reservoir in Heihe, Shaanxi Province as an example, a simulation model based on multiple intelligent optimization algorithms is established to predict the inflow runoff of the reservoir. At the same time, historical data of different time series, such as precipitation and runoff, are selected as input factors to compare the prediction ability and results of BP, WOA-BP, ICEEMDAN-BP and ICEEMDAN-WOA-BP models under the same input factor conditions. The results show that as far as the input sequence is concerned, the prediction effect of the model with precipitation as the input factor is better than that of the model with runoff as the input factor; For different algorithms, ICEEMDAN-WOA-BP model has good stability, Nash coefficient can reach 80%-90%, and the prediction accuracy is higher. The proposed ICEEMDAN-WOA-BP model can provide technical support for river runoff prediction, reservoir hydrological prediction and watershed water resources management.

In order to solve the problem of instability of the bottom plate and pressure damage of the suspended grid due to the excessive time-average pressure in the suspended grid stilling basin, numerical simulation was used to study the water level difference and pressure field in four different arrangements of the suspended grille under the design and calibration flow. Two optimization schemes of the combined toe pier-suspended grille and circularized suspended grille were proposed on the basis of the scheme 4 with better water stabilization effect. The results show that the combined toe pier-hanging grille optimisation scheme can reduce the time-average pressure at the bottom plate by 63% and 50% compared to scheme 4 at the design and calibration flow rates, effectively reducing the difference in the time-average pressure Δp₂ between the upper surface C and the lower surface D of the grille in the basin. The rounded grille optimisation scheme can make the total pressure distribution at the grille more uniform and avoid local damage to the grille. Therefore, it is recommended to choose a combined auxiliary energy dissipation method of toe pier-suspended grille for high flow stilling basin with pressure requirements.

The Guangxi coastal of Beibu Gulf has abundant water resources, but the inter-annual distribution is uneven under the influence of El Niño/La Niña events. The Nanliu River is the largest river located in the costal of Beibu Gulf, Guangxi. Based on SWAT model, the characteristics of blue water, green water flow, and green water storage in typical El Niño/La Niña years in the river basin were quantitatively analyzed. The results show that from 1971 to 2015, the annual average blue water, green water flow, and green water storage in the river basin was 835.0 mm/year, 929.0 mm/year, and 114.0 mm/year, respectively. In the typical El Niño years (1997)/La Niña years (2007), the blue water, green water flow and green water storage in the river basin are 145.7%/51.6%, 92.4%/96.9% and 115.5%/78.3% of the multi-year average, respectively. The El Niño/La Niña event caused a significant increase/decrease in precipitation in the river basin, which mainly affected the amount of blue water. Due to humid climate in the basin, the amount of green water flow was mainly affected by solar radiation and wind speed. The research can provide an important reference for the rational and efficient utilization of water resources and the high-quality development of the region.

Manually planning concrete gravity dam pouring scheme is time consuming, lower efficiency and complex. It is also difficult to make adjustment and to visualize the process. An automatic BIM-based pouring scheme planning system is proposed. The system associates the pouring information with the BIM model directly, and is capable to do the pouring-related parameters calculation, pouring constraints customization, dam blocks scheduling, Gantt charts drawing, dam timeframe display, pouring process visualization. Finally, this paper uses the Zhuxi Dam as an example to verify the efficiency and intuitiveness of the system, which provides a reference for research on the development of similar systems.

Cross building is inevitable in water diversion projects, and the structural state of cross buildings is crucial to the safe operation of the project. Based on a water transfer project in Henan Province, a three-dimensional finite element model of cross-crossing of water pipeline structures in the inverted siphon and water transfer project of the South-North Water Transfer Central Project was established by taking into account the coupling effect between soil-water-structure in the process of water transfer and diversion. The structural state effect of cross building under each simulation operating condition was analyzed by considering the periods of unconstructed structure, completion, normal operating. The results show that the cross-crossing building has impact on the existing building, especially for the large change of structural state in cross part. The maximum tensile stress in the inverted siphon structure increases from 0.54 MPa to 0.97 MPa, and the maximum settlement increases from -1.38 mm to -1.90 mm; The tensile stress in the aqueduct increases from 1.03 MPa to 1.34 MPa, and the maximum settlement increases from -3.78 mm to -4.07 mm. The stress value and settlement amount can meet the engineering requirements. Moreover, with the increase of the buried depth of the two supports of the water pipeline, the less the impact on inverted siphon is. The research results can provide reference for the analysis of similar projects.

Aiming at the two failure modes of hydraulic steel gates, the relative deformation failure under the normal service state and the bending shear composite strength failure under the limit state of bearing capacity, the corresponding failure probability analysis models were established respectively. The influence of different parameter distribution types on the failure probability of two failure modes of outcrop steel gates and deep-hole steel gates in hydraulic steel gates was explored through Monte Carlo simulations. The results show that under the same failure mode, when the coefficient of variation of the variable itself remains unchanged, the failure probabilities obtained by different distribution types are relatively close. Compared with the outcrop gate, the deep-hole gate has a higher failure probability and is more prone to instability. But the type of parameter distribution has little influence on the failure probability of deep-hole gate and has great influence on the outcrop gate. When the random variables of each parameter follow the logarithmic normal distribution, it will have a relatively maximum failure probability. It is easy to overestimate the reliability of hydraulic steel gates by considering only the normal distribution.

With the increase of economic development and the frequency and intensity of flood disasters, post-disaster emergency management requires rapid understanding of disaster losses. This paper firstly constructed an index system from five aspects including disaster-causing factors, disaster-bearing bodies, disaster-pregnant environment, emergency response capacity and disaster situation, and verified its rationality based on generalized gray correlation analysis. Secondly, Gaussian process regression model was introduced to pre-evaluate and simulate the economic losses of flood disasters. Finally, the method was applied to evaluate the direct economic losses of flood disasters in Beijing-Tianjin-Hebei urban agglomeration from 2010 to 2020. The results show that the generalized gray correlation analysis-Gaussian process regression model has the best fitting accuracy when comparing the simple Gaussian process regression with the neural network assessment model.

When there is a leakage point in the water supply pipe network, it is not easy to be detected due to its concealment, and the long-term leakage accumulation will not only cause waste of water resources, but also lead to the problem of poor production and marketing of water supply. The frequency domain analysis was introduced into the water supply industry, and a node pressure of water supply pipe network based on FFT was proposed. Firstly, the specific method is called EPANET by writing a program to optimize the operation simulation of water supply pipe network, and then solve the optimal pump and valve scheduling scheme back into the simulated leakage point working condition. With the help of Fourier transform to convert the time-varying node pressure into an amplitude signal, the pipeline node pressure was analyzed from the perspective of the frequency domain. Therefore, the length range between the leakage point and the starting node of the pipeline was judged. Through verification and compared with the previous pressure based analysis of the leakage point, the proposed method can judge whether the pipeline is normal operation and the location range of the leakage point from the perspective of frequency domain.

In the condition monitoring of pumped storage units, vibration velocity signal is often integrated into the displacement signal, and then calculate characteristic values for unit evaluation. Taking the horizontal vibration velocity signal of upper bracket of a case unit under stable working condition as an example, the method of integrating velocity signal into displacement signal and the setting of filter parameters are studied. Furthermore, vibration signal in transient working condition is adopted for verification. The results indicate that a high-pass filter shall be used when the vibration velocity signal is integrated into the displacement signal under stable conditions, and the cut-off frequency of the high-pass filter can be set as per 0.2 times of the rotational frequency. Under transient conditions, there is a risk of over estimating unit vibration when using unfiltered displacement signals integrated from velocity signals to calculate characteristic values for unit safety assessment.