Climate change and urbanization development have brought great challenges to reservoir flood control and disaster mitigation, and reservoir regulation is one of the important non-structural means for controlling floods. Therefore, this study applies the bibliometrics method and visualization analysis tools (CiteSpace and VOSviewer) to conduct a systematic quantitative analysis of the Chinese literature regarding the research topic of reservoir flood control regulation. The results indicate that the number of Chinese literature on reservoir flood control regulation can be divided into three periods in terms of the publication time, and the number of publications in different periods witnesses the development history of reservoir flood control regulation technology in China; The co-occurrence analysis of keywords provided the top 10 keywords in terms of frequency and centrality. The emergence analysis provided the development history of high popularity keywords since 2000. Cluster analysis classified keywords with significant correlation and displayed the relationship between different clusters; The analysis of authors, institutions, and literature sources can provide guidance for relevant researchers in the Chinese journal selection during the manuscript submission and the collaborator choices in Academia.

In order to solve the problem that the one-dimensional SWMM model is difficult to visually display the submerged depth and range of the study area, taking a residential area in Brighton as an example, the SWMM model coupled with the LISFLOOD-FP two-dimensional hydrodynamic model has a low impact on the residential area. The waterlogging situation before the development and renovation was analyzed and the inundation range and water depth map were made, and three different low-impact development (LID) schemes (single green roof scheme, single permeable pavement scheme, and combination scheme) were designed to transform the residential area. The results show that the inundation range is consistent with the actual waterlogging points, which shows that the two-dimensional coupling model has high reliability, and the three low-impact development schemes can effectively eliminate overflow nodes, reduce runoff peaks, and delay peak occurrence time and water receding time, which is of great significance to improve urban drainage and reconstruction technology.

In order to explore the solution to the risk of ponding and waterlogging in the sub-catchment area during sponge city design, SWMM modeling was used to study the peak runoff control characteristics of LID facilities and their combinations under different recurrence interval, as well as the peak runoff control laws of the incremental scale of volumetric LID facilities. The study shows that the peak runoff control effect of volumetric LID facilities is mainly achieved through peak time delay, while the peak runoff control effect of permeable LID facilities is mainly achieved through overall runoff reduction, and the peak runoff control effect of volumetric LID facilities is more significant; Only the combination of permeable LID facilities cannot significantly reduce peak runoff and delay peak time on a rainfall event with a recurrence interval of 5 years or more. When combined with volumetric LID facilities, it can achieve a peak runoff reduction rate of over 20% for rainfall with a recurrence interval of less than 10 years; When the scale of permeable LID facilities increases by 60% or more, the peak runoff reduction effect is more obvious for rainfall with a recurrence interval of 50 years or less; When its scale increases by 80% or more, it can basically ensure that the total runoff volume of post-development does not exceed which of pre-development with a recurrence interval of 50 years or less. The research results are aimed at exploring solutions to the risk of ponding and waterlogging in local areas, which provides theoretical reference for the design of peak runoff control in actual sponge city sub-catchments.

Continued land development around the world has accelerated the construction of impervious surfaces, thereby changing the hydrological cycle of the natural environment itself, resulting in frequent urban waterlogging disasters. Due to its own limitations, the old city not only cannot reasonably utilize rainwater resources, resulting in a waste of rainwater resources, but also is often in the predicament of flooding every time when it rains. Taking the Nandajie area of the old city of Xifeng District in Qingyan City, Gansu Province as an example, the construction effect of different LID measures in each return period was simulated through SWMM modeling. The best LID measures suitable for the study area were selected. The results show that the reduction effect of the combined measures is the best, the reduction rates of the total runoff and the peak runoff are over 68.71% and 68.90%, respectively, the peak time is delayed between 10-15 minutes, and the reduction rate of the overload of the pipe network decreases with the increase of rainfall return period. The research results provide reference for optimization of LID measures in the old urban areas of Northwest China.

Analyzing the spatial and temporal distribution characteristics of flash flood disasters is crucial for flood control and prevention. Taking Guangdong Province as an example, this study first compiled historical data on flash flood disasters in Guangdong Province from 2017 to 2021. Using methods such as standard deviation ellipse and kernel density, the spatial and temporal characteristics were analyzed, and the complex interaction relationships of triggering factors were explored. The results show that there were a total of 79 flash flood disasters, mainly concentrated in May and June, with uneven temporal distribution. The spatial distribution pattern of flash flood disasters exhibited a "dispersed east and west, concentrated north and south" pattern, with the northern cities of Heyuan, Shaoguan, and Meizhou being high-risk areas for flash flood disasters. Short-duration heavy rainfall was the main driving factor for flash flood disasters, with significant influences from topography, vegetation cover, and land use. The findings of this study can provide reference for flash flood disaster prevention and control in Guangdong Province.

The study of water-sediment processes and dam-land-erosion mechanisms under warping-dam-break conditions is of great significance for the construction and later management of warping dams in the Loess Plateau. Based on the literature research and field investigation, this paper identified the main causes of dam-land-erosion under warpingdam-break conditions, including the nature of the dam soil, the formation characteristics of the dam and the check dam break mode. It proposed that the process of dam erosions and gully erosions after warping dam failures was as follows: “warping dam failure → retrogressive erosion → scouring and undercutting → collapse of gully walls → mixed flow of water and sand”. Taking the ^#2 main dam in Macaoli of Lishi District in Lvliang City, Shanxi Province as an example, the numerical calculation results indicate that the water-sand process under the condition of warping dam failures was significantly changed by the siltation of the reservoir areas, and the dam lands have the role of shaving peaks and sinking sands.

Reasonable data mining and accurate prediction and analysis of concrete dam deformation monitoring data are the key means to ensure the safe and long-term operation of the dam. Due to the impact of environmental variables such as temperature and water level, the dam deformation time series has periodic, nonlinear and other change characteristics. Existing intelligent algorithms can not capture the nonlinear relationship of sequences well, A concrete dam deformation prediction model based on EEMD-AEFA-LSTM model was proposed. Ensemble empirical mode decomposition was used to effectively decompose the deformation time series. The long short-term memory network model optimized by the artificial electric field algorithm was used to predict the decomposition components and reconstruct the prediction results. The deformation monitoring data of EX16 and EX24 measuring points of a concrete dam were selected for prediction research. The results show that the prediction accuracy of the EEMD-AEFA-LSTM model is significantly higher than that of the AEFA-LSTM model, PSO-LSTM model, and GA-LSTM model. The average absolute error, mean square error, and root mean square error of the prediction results are the minimum values, providing a new way for accurate prediction of concrete dam deformation.

In view of the fact that traditional neural network models can hardly make full use of the topological relationship of the backward forward information of dam deformation monitoring time series data, while the bidirectional long short-term memory (BiLSTM) can effectively learn the backward forward information, a combined dam deformation prediction model BES-BiLSTM was proposed based on bald eagle search algorithm optimized bidirectional long short-term memory neural network. Firstly, the bald eagle search algorithm was used to optimize parameters of the model. Secondly, the bidirectional learning feature of BiLSTM was used to train the model to enhance the correlation between the data. Then, the settlement value of a concrete dam hydropower station was taken as example 1 for dam deformation prediction based on the BES-BiLSTM model. Another concrete dam horizontal displacement value was taken as example 2 to verify the model performance. Finally, the prediction results of the BES-BiLSTM model were studied in comparison with those of the traditional long and short term memory neural network (LSTM) model and the BiLSTM model. The results show that the BES-BiLSTM model has stronger fitting and prediction capabilities than the single traditional LSTM and BiLSTM models, which can be used for deformation prediction of concrete dams and slopes.

For side channel spillways, although the adjustment section can be arranged on the downstream side to smooth the water flow, it is difficult to completely avoid the interference of the transverse axis spiral flow on the water flow pattern of the chute. Through numerical simulation, the impacts of the curved circulation in the turning section of the chute on the spiral flow on the lateral axis of the side trough were studied. The results show that when the direction of the circulation and the spiral flow are the same (the turning angle is 14.505°), the streamline in the bend rolls obliquely from the concave bank to the convex bank, the superposition of the flow velocity is obvious, and the circulation intensity intensifies. The lateral flow velocity of the outlet section of the curve reaches 3.29 m/s, and the height difference of the outlet water surface has reached 1.140 m (low left and high right); When the circulation flow of channel bend and spiral flow are in opposite directions (the turning angle is -5°); The water flow in the bend turns from both sides to the axis and then flows downstream, and the circulation phenomenon almost disappears; The lateral flow velocity at the outlet section of the bend decreases to -0.19 m/s, and the height difference of the outlet water surface decreases to -0.467 m (high left and low right). That is, the turbulence of the spiral flow in the upstream groove can be improved by providing a curved path in the chute.

The water flow disorder, shock, spray splashing out of the side wall and incomplete water jump are often caused by insufficient discharge energy dissipation in the pool. In order to solve this problem, the influence law of the layout of T-shaped pier and its parameter variation on the hydraulic characteristics in the ballast tank was studied by using the model test method and numerical simulation. The results show that the energy dissipation rate increases with the increase of the length of T-shaped pier legs; The water depth increases with the installation of the impingement baffle, and the efficiency increases, and the energy dissipation rate decreases with the increase of the impingement baffle; The flow state of the water in the stilling pool is stable after the double-row T-shaped piers are arranged, and the energy dissipation increases first and then decreases with the increase of the distance between the front and back. According to the simulation results, a reasonable scheme is recommended and verified by model test. The results show that the energy dissipation rate of the recommended scheme reaches 76.06%, which increases by 12.51%. The flow state is stable and meets the engineering requirements.