CN211816060U - Top-sealed dredging structure body for river channel dredging experimental research - Google Patents

Abstract

The top-sealing dredging structure is used for the experimental study of river channel dredging. The longitudinal section of the lower part of the dredging structure is a solid trapezoid. and the backflow surface, the upper part of the dredging structure is a plate body with both front and rear planes, the front and rear planes of the plate body are parallel, and a plurality of overcurrent and sand flushing holes are opened on the plate body. Sand holes are circular or rectangular or trapezoidal or conical or triangular. The basic experimental device of this structure conducts experimental research on dredging, so as to continuously improve and enrich the research on the active dredging method using the water body itself to carry out sediment dredging.

Description

Top-sealed dredging structure for experimental study of river channel dredging

technical field

The utility model relates to a research model of dredging of river channels, in particular to a top-sealing type dredging structure body for experimental research of dredging of river channels, which belongs to the technical field of experimental research models.

Background technique

Many domestic rivers, water diversion channels and urban inland rivers have different degrees of sedimentation. The most direct influencing factor of sediment deposition is the reduction of the sand carrying capacity of water flow. In the field of sediment cleaning research, through the accumulation of long-term practice, it has gradually formed flood discharge and sediment discharge through hydraulic projects (such as Xiaolangdi Water Conservancy Project) and mechanical cleaning. There are two types of silting. The flood discharge and sediment discharge method by hydraulic engineering is an active dredging method by improving the sediment carrying capacity of water flow. Basic device) took the lead in proposing "a basic device for river or channel dredging experiments". The dredging experimental basic device only provides a convenient basic condition for the majority of scholars in the research of dredging experiments, and does not include specific dredging structures. In order to provide reference for researchers in this field to conduct experimental research, the applicant's scientific research team also studied several dredging structures. The applicant has conducted preliminary experimental research on this series of structures. The experimental group has a significantly higher dredging effect than the control group. Because the engineering practice of the structural model involves the determination of various specific parameters of the engineering body, the determination of parameters is obtained through a series of experiments. optimal value or range. Therefore, the model body proposed in this application only involves the scope of experimental research for the time being, and provides scientific guidance for the practical application of the engineering structure through the later systematic experimental research. The determination of the optimal parameter value or range of this structure and the scientific exploration of other dredging structure models await the joint efforts of fellow scholars in the future.

SUMMARY OF THE INVENTION

The purpose of the utility model is to provide a dredging structure matched with the above-mentioned research and development of the above-mentioned basic device for dredging experiments of rivers or channels, which can be further used for experimental research of dredging.

In order to realize the purpose of the present utility model, the following technical scheme is adopted: a top-sealing dredging structure for experimental research on river channel dredging, the longitudinal section of the lower part of the dredging structure is a solid trapezoid, and the two trapezoids are The feet are all acute angles, and the longitudinal sides of the trapezoid are the upstream surface and the downstream surface respectively. The upper part of the dredging structure is a plate body with both front and rear planes. A plurality of overcurrent and sand-washing holes are opened, and the over-current and sand-washing holes are circular or rectangular, trapezoidal, conical or triangular.

Further, the plurality of over-current and sand-washing holes are in one row or multiple rows up and down. If there are multiple rows, the over-current and sand-washing holes are arranged in a matrix or in the shape of a "pin".

The positive and beneficial technical effects of the utility model are: the structure can be combined with the above-mentioned basic experimental device to carry out the experimental research on dredging, which provides a new approach, method and idea for the experimental research in this field. Research scholars provide an entry point to continuously improve and enrich the research on the active dredging method using the water body itself for sediment dredging.

Description of drawings

Figure 1 is a schematic diagram of the dredging structure.

Figure 2 is a schematic diagram of the combination of the dredging structure on the experimental tank.

FIG. 3 is a partial schematic view of the overflow sand flushing hole.

Detailed ways

In order to more fully explain the implementation of the present utility model, implementation examples of the present utility model are provided. These implementation examples are only the description of the present invention, and do not limit the scope of the present invention.

The present utility model will be explained in further detail with reference to the accompanying drawings, in which the marks are: 100: dredging structure; 1: trapezoid; 2: upstream surface; 3: downstream surface; 4: plate body; 5: overflowing sand flushing hole; 6: experimental slot; 7: rectangular hole; 8: triangular hole; 9: trapezoidal hole; 10: tapered hole.

As shown in the attached drawings, the top-sealed dredging structure is used for the experimental study of the river channel dredging. , the two feet of the trapezoid are acute angles, the longitudinal sides of the trapezoid are the upstream surface 2 and the downstream surface 3 respectively, the upper part of the dredging structure is a plate body 4 with both front and rear planes, and the front and rear of the plate body are flat. The planes are parallel, and the plate body is provided with a plurality of over-current and sand-washing holes 5, and the over-current and sand-washing holes are circular or rectangular, trapezoidal, conical, semicircular or triangular. Figure 3 shows the other four different shapes of overcurrent flushing holes. The plurality of over-current and sand-washing holes are in one row or multiple rows up and down. If there are multiple rows, the over-current and sand-washing holes are arranged in a matrix or in the shape of a "pin". The left and right sides of this dredging structure diagram are compatible with the two side walls of the experimental tank.

The design of this dredging structure is derived from the study of geological disaster prevention and control of mountain torrents and debris flows, and is proposed based on the very common sand-damping dam engineering structure in the prevention and control measures of mountain torrents and debris flow projects. Among them, debris flow dams are divided into permeable dams and impermeable dams. The former is optimized from the latter in order to reduce the hydrostatic pressure of the accumulation in front of the dam and improve the stability of the dam in the process of engineering practice. The application of sand dams in the field of mountain torrent and debris flow prevention and control comes from hydraulic dams built for flood regulation, water storage, and power generation. The most direct manifestation of hydraulic dams is water storage. The leading role of the sand dam is to trap and drain sand, while the role of the dredging structure proposed in this application is to conduct water and disturb the water body, thereby improving the turbulence and sand carrying capacity of the water body. . Compared with the dredging structure proposed in this patent, both the sand dam and the hydraulic dam use the storage capacity generated by the size of the large structure to intercept the target objects (sand dam to block sand and hydraulic dam to block water). It is placed inside the river channel, the structure is completely immersed in the water environment, and the disturbance of the structure is used to improve the turbulence of the water body, and the final macroscopic performance is to improve the sand-carrying capacity of the water flow.

The experimental model body of the top-sealing dredging structure of the present application is a structure body with a trapezoidal lower section and a rectangular upper section. Based on the current experimental research, the section of the groove section is generally rectangular or trapezoidal, and the cross section of the structure reflected in this patent is a trapezoidal section. The lower part of the structure is a solid structure, which has two main functions: 1) Increase the gravity of the structure itself and enhance the stability of the structure in the water environment; 2) Under the influence of the structure, the water flow with sand will increase the impact on the riverbed. 3) The scouring and erosion at the bottom of the channel, the lower solid structure will effectively prevent the water body from producing transitional dredging of the river channel; 3) The lower solid structure will affect a certain range of the upstream area of the river channel, and allow a certain amount of sediment deposition and sedimentation within this range. The silted sediment can further effectively protect the bottom of the river channel from erosion. The upper part of the structure has a rectangular cross-section, and additional sand-flushing holes are added. The sand-flushing holes have the following functions: 1) Based on the fact that the structure exists in the underwater environment, the vertical water pressure is used to enhance the flow of water through the flow and flushing. 2) The addition of this structure will significantly increase the water level at the structure and upstream, reduce the cross-sectional area of the river channel, and the sand flushing holes will be enhanced. The overcurrent capability of the structural section is to try to reduce the above-mentioned undesirable factors.

The lower part of the structure is a trapezoid section, that is, the bottom angle of the trapezoid is an acute angle. The reasons are qualitatively described as follows: 1) The slope gradient of the oncoming surface of the structure is "1:i" (i>0); the oncoming surface of the structure is inclined Compared with the upright state, the backflow disturbance of the water body near the upstream direction of the structure body is more effectively reduced, which is conducive to retaining the original kinetic energy of the water body; the inclined state of the upstream surface of the structure body is conducive to bearing more hydrostatic pressure from directly above it, which is more conducive to the structure Anti-slip and anti-overturning ability of the body. 2) The slope gradient of the backflow surface of the structure is “1:j” (j>0), and the inclined state of the backflow surface of the structure is more effective than the vertical state to reduce the energy dissipation of the water body that causes the “waterfall” effect when the water body crosses the structure body. It is beneficial to retain the kinetic energy after the water body crosses the structure body; the inclined state of the backflow surface of the structure body is more conducive to the anti-overturning ability of the structure body than the upright state.

The sand-carrying capacity of the water flow after passing through the sand-flushing hole is related to the size and shape of the sand-flushing hole and the head difference at the sand-flushing hole. However, it is considered that the head difference at the overflowing sand hole is related to the cross-sectional area of the river channel and the upstream flow rate, and generally speaking, the upstream flow rate of a specific river channel is relatively stable in the short term and relatively stable in the long term. or gradient variables. Therefore, the influence of the head difference factor is not considered here. In order to better compare the influence ability of different flow-through sand-flushing holes, we tentatively set equal or similar flow-crossing cross-sectional area or flow-wet circumference as the pore body quantification, and the pore body shape as a variable. On the premise of obtaining the optimal cross-sectional shape without a large number of experiments, we tentatively recommend some common drainage hole shapes in the water-permeable sand-blocking dam protection project. The arrangement above the structure can be arranged in a "matrix" or "zigzag" arrangement. In addition, there should be no or as few sand-passing holes in the two edge areas of the structure close to the river channel, which can effectively reduce the hydrodynamic strength of the river channel slope on both sides of the structure body, so as to protect the river channel slope from being damaged. At the same time, the lower hydrodynamic environment can cause some sediment to deposit to a certain extent at the connection between the structure and the river channel, and the deposited sediment will further protect the slopes on both sides of the river channel.

After describing the embodiments of the present invention in detail, those who are familiar with the technology can clearly understand that various changes and modifications can be made without departing from the scope and spirit of the above-mentioned patent application. Any simple modifications, equivalent changes and modifications made in the examples belong to the scope of the technical solutions of the present invention, and the present invention is not limited to the implementation of the examples in the description.

Claims (2)

1. The top-sealing type dredging structure for the experimental study of river channel dredging is characterized in that: the longitudinal section of the lower part of the described dredging structure is a solid trapezoid, and the two feet of the trapezoid are acute angles, and the longitudinal two sides of the trapezoid are both acute angles. The sides are the upstream surface and the downstream surface respectively. The upper part of the dredging structure is a plate body with front and rear planes, the front and rear planes of the plate body are parallel, and a plurality of overcurrent and sand flushing holes are opened on the plate body. The over-current sand flushing hole is circular or rectangular or trapezoidal or conical or triangular. 2. The top-sealing type dredging structure for experimental research on dredging of river channels according to claim 1, is characterized in that: the multiple over-current scouring holes are one row or multiple rows up and down, if it is multiple rows, The overcurrent flushing holes are arranged in matrix or "pin" shape.

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