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CN-121766208-B - Method, medium and system for calculating mud-rock flow rate reduction rate of wedge-shaped beam type grating dam

CN121766208BCN 121766208 BCN121766208 BCN 121766208BCN-121766208-B

Abstract

The invention relates to the technical field of hydraulic engineering, in particular to a method, a medium and a system for calculating the mud-rock flow rate reduction rate of a wedge-shaped beam type grating dam, and aims to solve the technical problem that a traditional model for predicting the mud-rock flow peak flow rate reduction rate is not suitable for a novel optimized structure. The wedge-shaped beam type grid dam structure is provided, five key control factors including the volume weight, the scale, the channel gradient, the relative opening width and the angle of the wedge-shaped structure of the debris flow are considered by the system through a water tank test, and an experience and theory double-calculation model is constructed. According to the method, the control factors are dimensionless processed, an accurate peak flow reduction rate prediction model is established, and the problem of insufficient parameter consideration in the traditional method is solved. The test data verification shows that the model prediction result is reliable, the accuracy of the debris flow peak flow regulation effect evaluation is remarkably improved, and scientific basis and practical tools are provided for disaster risk prevention and control and prevention engineering design of mountain major engineering.

Inventors

  • HU GUISHENG
  • SHEN WENHAO
  • TIAN SHUFENG
  • PENG SHUAISHUAI
  • XU ZENGQIANG

Assignees

  • 中国科学院、水利部成都山地灾害与环境研究所

Dates

Publication Date
20260512
Application Date
20260302

Claims (7)

  1. 1. The method for calculating the mud-rock flow rate reduction rate of the wedge-shaped beam type grating dam is characterized by comprising the following steps of: s10, acquiring site parameters, selecting a section of a dam construction condition in a debris flow basin on site, determining the debris flow volume weight through a site investigation test, and acquiring the concentration of solid substances Mud depth h of mud-rock flow of front section of dam and average channel gradient in section range of designed wedge-shaped beam type grating dam ; S20, designing dam parameters, primarily determining the dam height H of the wedge-shaped beam type grating dam, and calculating the ratio of the debris flow scale to the reservoir capacity of the wedge-shaped beam type grating dam Or, preset design storage capacity ratio Then calculating the dam height H of the wedge-shaped beam type grating dam; S30, determining the width of an opening, acquiring particle grading curves of a plurality of positions of a debris flow basin, selecting a whole particle grading curve of the basin by combining the duty ratio of large particles in the basin, and determining the width b of the opening of a wedge-shaped beam type grating dam by determining the characteristic particle diameter d 95 of a debris flow sample of the debris flow basin; s40, calculating a flow reduction rate; calculating the mud-rock flow rate cutting rate by the following formula: ; Wherein, the To reduce the peak flow rate based on an empirical model, Is the ratio of the angle alpha of the wedge-shaped beam type grating dam wedge structure to 60 degrees.
  2. 2. The method for calculating the mud-rock flow rate cutting rate of a wedge-beam type grid dam according to claim 1, wherein in said step S10, the solid matter concentration is Calculated by the following formula: ; Wherein, the Is the volume weight of the debris flow, kN/m3, For the volume weight of the clean water, kN/m3, The volume weight of the solid matters wrapped by the debris flow is kN/m < 3 >.
  3. 3. The method for calculating the mud-rock flow rate of the wedge-beam type grating dam according to claim 2, wherein in the step S20, the reservoir capacity of the wedge-beam type grating dam is calculated by the following formula: ; preliminary determination of dam height of wedge beam type grating dam When the storage capacity ratio is Calculated by the following formula: ; Wherein, the The average width of the trench of the cross section of the wedge beam type grating dam is designed for the debris flow basin, For the minimum particle size value of the maximum block stone in the debris flow domain, Is the scale of the primary mud-rock flow.
  4. 4. The method for calculating the flow rate reduction rate of the mud-rock flow of the wedge-beam type grating dam according to claim 2, wherein in the step S20, a preset design storage capacity ratio is set Then, the dam height H of the wedge beam type grating dam is calculated by the following formula: ; Wherein, the The average width of the trench of the cross section of the wedge beam type grating dam is designed for the debris flow basin, For the minimum particle size value of the maximum block stone in the debris flow domain, Is the scale of the primary mud-rock flow.
  5. 5. A method for calculating a mud-rock flow rate reduction rate of a wedge-shaped beam type grating dam according to claim 2 or 3, wherein the angle ratio of the wedge-shaped structure of the wedge-shaped beam type grating dam is as follows The value is 1.0, and the ratio of the total solid matters of the debris flow to the capacity of the wedge-shaped beam type grating dam The value is 3.0.
  6. 6. A non-transitory computer readable storage medium storing a computer program, characterized in that the computer program when executed by a processor implements the steps of the method according to any one of claims 1 to 5.
  7. 7. A debris flow control engineering design system, comprising a memory and a processor, the memory storing a computer program, the processor implementing the steps of the method according to any one of claims 1 to 5 when executing the computer program.

Description

Method, medium and system for calculating mud-rock flow rate reduction rate of wedge-shaped beam type grating dam Technical Field The invention relates to the technical field of hydraulic engineering, in particular to a method, a medium and a system for calculating the flow rate reduction rate of mud-rock flow of a wedge-shaped beam type grating dam. Background Debris flow is a sudden geological disaster which is widely distributed in mountain areas in China and seriously harmed. Along with the promotion of heavy projects such as the Sichuan-Tibetan railway, the threat of the heavy projects is increasingly prominent. The physical retaining dams (such as gravity dams) in the traditional prevention and treatment engineering have core defects of poor water permeability, easy storage siltation, easy dam foundation damage and the like in practical application, have short disaster reduction function, and can be converted into secondary material sources by themselves and siltation substances, so that downstream risks are aggravated. In order to overcome the defects of the physical dams, a permeable sand blocking dam (such as a grid dam) is generated, and the concept of blocking coarse rows and fine rows is more ecological. However, the development of the dam body faces two major bottlenecks, namely, firstly, the design theory is seriously lagged behind engineering practice, the current design depends on subjective experience, and lacks general theoretical model guidance, so that the function implementation has great uncertainty, secondly, the structure function and mechanism are unknown, the existing structure optimization focuses on the blocking and discharging effect and stability, and fundamental innovation from the aspects of debris flow motion trail and energy dissipation is generally neglected. Particularly, the debris flow peak flow reduction rate serving as a core index for measuring the regulation effect has obvious defects in the existing prediction model. The control parameters (such as volume weight, channel gradient and the like) considered by most models cannot fully incorporate the influence of the key factor of 'debris flow scale', so that prediction accuracy is limited. Therefore, when the dam structure evolves to a novel optimized structure such as a wedge beam type grating dam according to the present invention, the conventional model is no longer applicable. In view of the foregoing, there is a need in the art for a precise and reliable peak flow reduction rate calculation method capable of tightly combining with the structural features of a novel dam body and considering key control factors such as debris flow scale by a system, so as to fill the gap from theory to design practice. Disclosure of Invention Aiming at the technical problem that the traditional model for predicting the mud-rock flow peak flow reduction rate is not suitable for a novel optimization structure of a wedge-shaped beam type grating dam, the invention provides a mud-rock flow reduction rate calculation method of the wedge-shaped beam type grating dam, provides a scientific, accurate and practical mud-rock flow peak flow reduction rate calculation and engineering design method, and has important theoretical significance and engineering application value. The technical scheme of the invention is as follows: a method for calculating the flow rate reduction rate of mud-rock flow of a wedge-shaped beam type grating dam comprises the following steps: s10, acquiring site parameters, selecting a section of a dam construction condition in a debris flow basin on site, determining the debris flow volume weight through a site investigation test, and acquiring the concentration of solid substances Mud-rock flow mud depth h and ditch bed gradient of front section of dam ; S20, designing dam parameters, primarily determining the dam height H of the wedge-shaped beam type grating dam, and calculating the ratio of the debris flow scale to the reservoir capacity of the wedge-shaped beam type grating damOr, preset design storage capacity ratioThen calculating the dam height H of the wedge-shaped beam type grating dam; S30, determining the width of an opening, acquiring particle grading curves of a plurality of positions of a debris flow basin, selecting a whole particle grading curve of the basin by combining the duty ratio of large particles in the basin, and determining the width b of the opening of a wedge-shaped beam type grating dam by determining the characteristic particle diameter d 95 of a debris flow sample of the debris flow basin; S40, calculating a flow reduction rate. Optionally, in the step S10, the solid matter concentrationCalculated by the following formula: ; Wherein, the Is the volume weight (kN/m 3) of the debris flow,Is the volume weight (kN/m 3) of the clean water,The volume weight (kN/m 3) of the solid matter which is wrapped by the debris flow. Optionally, in the step S20, the reservoir capacity of the wedge beam