Debris flow along the automatic shunt dredging sand - stop silt combination structure and construction method

Abstract

The present application relates to the field of water conservancy disaster prevention and mitigation, and particularly relates to a debris flow automatic diversion dredging and sand blocking-stopping combination structure and a construction method. The combination structure comprises a plurality of automatic diversion dredging and sand blocking-stopping units arranged in sequence along the flow direction of the river water, each unit comprising a crescent-shaped diversion structure, a self-dredging sand blocking dam structure and a funnel-shaped sand stopping field structure. The crescent-shaped diversion structure is distributed in a crescent shape by concrete columns or gabion columns and connected by impermeable geotextile, filled with soil and stone mixture and covered with vegetation on the top. The self-dredging sand blocking dam structure is transversely arranged in the river, provided with a drainage hole, a gate and an overflow port. The funnel-shaped sand stopping field structure comprises an inclined slope, a funnel-shaped sand stopping pool and a sand discharge hole, and is provided with a planting groove on the periphery. The combination structure arranged in the river can effectively intercept debris flow and realize automatic diversion dredging, reduce manual maintenance, improve the effect of disaster prevention and mitigation, and has the function of ecological restoration.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of water conservancy disaster prevention and mitigation, and particularly relates to a mud flow automatic diversion and dredging sand blocking-stopping combination structure and a construction method thereof. BACKGROUND

[0002] Mud flow is a geological disaster with strong destructive power, suddenness, large damage and wide range of harm, which often leads to river blockage, infrastructure damage and ecological environment destruction. Moreover, with the increase of global climate change and human activities, the frequency and intensity of mud flow disasters are on the rise. In order to effectively prevent and control mud flow disasters, various sand blocking dams, diversion dams and silt stopping fields and other engineering measures are widely used in mud flow channels.

[0003] At present, mud flow prevention and control engineering mainly includes blocking engineering, diversion engineering and silt stopping engineering. The blocking engineering such as sand blocking dam is mainly used to intercept the solid materials in the mud flow to reduce the downstream disaster; the diversion engineering such as diversion dam is used to divert the mud flow to different areas to reduce the impact force of a single area; and the silt stopping engineering such as silt stopping field is used to collect and store the mud and sand in the mud flow to reduce the downstream river channel siltation.

[0004] In the prior art, CN103195024A discloses a mud flow diversion dam for automatically distributing and stopping the amount of mud flow and a design method thereof. The mud flow diversion dam is arranged between a diversion channel and a silt stopping field, and includes a dam body foundation and a dam body arranged on the dam body foundation. The bottom of the dam body is provided with a diversion hole connected with the diversion channel, and the top of the dam body is provided with a diversion weir connected with the silt stopping field, which is used to reasonably distribute the mud flow to the diversion channel and the silt stopping field. However, the mud flow diversion dam is a rigid structure, which is difficult to adapt to the dynamic changes of the erosion path of the mud flow along the path, and is easy to cause local siltation or erosion intensification, thereby reducing the prevention and control effect. Moreover, it is difficult to clean up the deposited mud and sand, the maintenance cost is high, and the mechanical dredging may further damage the ecological environment.

[0005] CN108867569A discloses a mud flow sand blocking dam for natural dredging and application thereof. The mud flow sand blocking dam includes a main dam body and a scouring auxiliary structure located on the backwater side of the main dam body. The natural dredging is achieved by disassembling the prefabricated components and using the mountain flood to scour the mud and sand in the reservoir area, thereby solving the problem of difficulty in dredging after the existing mud flow blocking dam is full. However, the prefabricated components need to be manually disassembled and installed, which is complicated to operate.

[0006] Therefore, the existing debris flow prevention structure still has the following problems: first, the rigid structure is difficult to adapt to the dynamic change of the erosion path of the debris flow along the way, and the prevention effect is poor; second, the traditional sand dam and sedimentation field are difficult to clean up after the deposition of mud and sand, and the maintenance cost is high, even if the natural dredging method disclosed in CN108867569A, artificial disassembly and installation of prefabricated components are required, and the operation is complex; third, mechanical dredging may further damage the ecological environment and affect the recovery of the natural ecological system of the river channel. SUMMARY

[0007] In view of the poor adaptability, difficult dredging and maintenance, and ecological damage of the existing debris flow prevention structure, the present application provides a debris flow automatic diversion and dredging sand-damming and sedimentation combined structure and construction method, which automatically diverts, intercepts, deposits and self-dredges the natural water flow or debris flow in the movement process by reasonably arranging the crescent-shaped diversion structure, self-dredging sand dam structure, funnel-shaped sedimentation field structure and covering vegetation, effectively reducing river channel deposition and erosion, reducing artificial cleaning cost, and using ecological-rock-soil coupling to enhance the stability, durability and environmental friendliness of the structure.

[0008] The present application provides a debris flow automatic diversion and dredging sand-damming and sedimentation combined structure.

[0009] The debris flow automatic diversion and dredging sand-damming and sedimentation combined structure comprises at least one automatic diversion and dredging sand-damming and sedimentation unit. Each automatic diversion and dredging sand-damming and sedimentation unit comprises a crescent-shaped diversion structure, a self-dredging sand dam structure and a funnel-shaped sedimentation field structure arranged in sequence along the flow direction of the water flow.

[0010] The crescent-shaped diversion structure is in the shape of a crescent as a whole, is arranged at the entrance of the bend of the river channel along the bending direction of the bend of the river channel, and the top is covered with vegetation, which is used to guide the water flow or debris flow to divert along the set path to reduce the impact on the downstream self-dredging sand dam structure, and also to enhance the anti-erosion capacity and self-dredging capacity of the structure; the covering vegetation fixes the soil and protects the slope, and improves the ecological benefits;

[0011] The self-dredging sand dam structure comprises a main dam body transversely arranged on the river channel, which is used to guide the water flow to pass through the main dam body directly to carry away the accumulated body or to enter the funnel-shaped sedimentation field structure for dredging in normal times, and is also used to guide the debris flow to overflow smoothly into the funnel-shaped sedimentation field structure for sedimentation when the debris flow breaks out;

[0012] The funnel-shaped sedimentation field structure is arranged on one side close to the convex bank of the river channel, which is used to accumulate the debris flow and gradually deposit, converge and concentrate the mud and sand in the debris flow through the funnel-shaped structure when the debris flow breaks out.

[0013] Preferably, the crescent-shaped diversion structure comprises a plurality of circular concrete columns; the plurality of circular concrete columns are distributed in a crescent shape and enclosed by impermeable geotextile to form a crescent-shaped space; and the crescent-shaped space is filled with soil-rock mixture.

[0014] The plurality of circular concrete columns are distributed in a crescent shape to form the main frame of the crescent-shaped diversion structure. Adjacent two circular concrete columns can be closely arranged or have a gap. By installing impermeable geotextile to enclose, a crescent-shaped space relatively isolated inside and outside is formed, which is used to hold the soil-rock mixture filled therein.

[0015] Preferably, the crescent-shaped diversion structure comprises square concrete columns and gabion columns; the plurality of square concrete columns and the plurality of gabion columns are arranged alternately and distributed in a crescent shape, and enclosed by impermeable geotextile to form a crescent-shaped space; and the crescent-shaped space is filled with soil-rock mixture.

[0016] One square concrete column, one gabion column, one square concrete column, one gabion column, one square concrete column, and so on, are arranged alternately. The arrangement of square concrete columns and gabion columns alternately can reduce the use of concrete.

[0017] The plurality of square concrete columns and the plurality of gabion columns are arranged alternately and distributed in a crescent shape to form the main frame of the crescent-shaped diversion structure. Adjacent square concrete columns and gabion columns can be closely arranged or have a gap. By installing impermeable geotextile to enclose, a crescent-shaped space relatively isolated inside and outside is formed, which is used to hold the soil-rock mixture filled therein.

[0018] Preferably, the main dam body of the self-dredging sand retaining dam structure is provided with a drainage hole and an overflow port which can communicate the flow face and the back flow face;

[0019] The drainage hole is arranged on the side of the main dam body close to the concave bank of the river, and is provided with a gate which can be opened and closed;

[0020] When the gate is opened, the water flow passes normally, and when the gate is closed, the water flow is accumulated;

[0021] The overflow port is arranged on the side of the main dam body close to the convex bank of the river and at the upper part of the main dam body, and is used to guide the water flow or debris flow to the funnel-shaped deposition field structure.

[0022] Preferably, the funnel-shaped deposition field structure comprises an inclined slope, a funnel-shaped deposition pool, and a deposition hole;

[0023] The inner cavity of the funnel-shaped deposition pool is in a spiral shape with multiple steps, which is large at the top and small at the bottom;

[0024] The inclined slope is arranged at the entrance of the top of the funnel-shaped deposition pool and connected with the overflow port of the self-dredging sand retaining dam structure, and the deposition hole is arranged at the bottom or side of the funnel-shaped deposition pool.

[0025] Preferably, the funnel-shaped deposition field structure further comprises planting grooves arranged at the periphery of the funnel-shaped deposition pool; and the top of the planting grooves is covered with vegetation.

[0026] Preferably, the groove body of the planting groove is mainly made of concrete or gabion, and the inside of the groove body is filled with soil and stone mixture.

[0027] Preferably, the vegetation comprises trees and vines, a steel wire mesh is arranged between a plurality of trees, and the vines climb onto the steel wire mesh relying on the branches of the trees, forming an ecological protection net.

[0028] The application further provides a construction method of the debris flow along the course automatic diversion dredging sand-blocking-deposition combined structure.

[0029] The construction method comprises the following steps: firstly, selecting a site and processing a foundation; then, constructing a crescent-shaped diversion structure, constructing a self-dredging sand-blocking dam structure, constructing a funnel-shaped deposition field structure, and covering vegetation according to the debris flow along the course automatic diversion dredging sand-blocking-deposition combined structure; and finally, performing trial operation and joint debugging on the automatic diversion dredging sand-blocking-deposition unit after the construction is completed.

[0030] Preferably, the site selection refers to selecting a debris flow prone area, determining a river bend with strong water flow power and obvious concave bank erosion as a construction area, and ensuring that the natural water flow can be diverted and dredged.

[0031] Preferably, the foundation processing refers to cleaning the soft soil layer of the riverbed and the two banks in the construction area, and reinforcing the foundation according to the geological conditions, so as to ensure the stability of the foundation.

[0032] The application has the following beneficial effects.

[0033] (1) The water flow is guided by the crescent-shaped diversion structure, the natural scouring effect is used to automatically divert and dredge the mud and sand, the artificial cleaning cost is effectively reduced, and the problem of dredging and maintenance of the traditional debris flow prevention structure is solved.

[0034] (2) The drainage holes and the gate of the self-dredging sand-blocking dam structure can control the discharge of the mud and sand, and the overflow port ensures that the debris flow can smoothly overflow when a large-scale debris flow occurs, thereby improving the adaptability of the structure to the dynamic changes of the debris flow along the erosion path.

[0035] (3) The funnel-shaped deposition field structure adopts a multi-stage deposition mode, avoids one-time large amount of mud and sand accumulation, improves the storage efficiency, ensures the long-term stable operation of the dam body, and effectively deals with multiple frequency debris flow events.

[0036] (4) The vegetation measures such as planting grooves, trees, vines and the like are combined to promote ecological restoration, realize the coordinated coexistence of the project and the natural environment, and reduce the damage of the traditional debris flow prevention structure to the ecological environment.

[0037] (5) By combining hydrodynamics, geomorphic evolution mechanism and ecological restoration technology, the synergy of rock-soil mechanics and ecological restoration is realized, and the sustainability and stability of the project are improved. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 Figure 1 is a schematic diagram of the flow state of a natural river along the erosion path and three key cross sections A, B and C; the dotted arrow in the figure schematically shows the main path of water flow movement.

[0039] Figure 2 Figure 2 is a schematic diagram of the state of two groups of automatic shunting, dredging, sand blocking and stopping units arranged along the path in the automatic shunting, dredging, sand blocking and stopping combined structure of the mud flow along the path.

[0040] Figure 3 Figure 3 is a top view structural schematic diagram of two typical structures of the crescent-shaped shunting structure in the application. Figure 3 Figure 3 (a) is a top view structural schematic diagram of the first typical structure of the crescent-shaped shunting structure, Figure 3 Figure 3 (b) is a top view structural schematic diagram of the second typical structure of the crescent-shaped shunting structure.

[0041] Figure 4 Figure 4 is a longitudinal sectional structural schematic diagram of two typical structures of the crescent-shaped shunting structure in the application. Figure 4 Figure 4 (a) is a longitudinal sectional structural schematic diagram of the crescent-shaped shunting structure formed by the crescent-shaped structure surrounded by circular concrete columns, Figure 4 Figure 4 (b) is a longitudinal sectional structural schematic diagram of the crescent-shaped shunting structure formed by the crescent-shaped structure surrounded by the staggered arrangement of square concrete columns and gabion columns.

[0042] Figure 5 Figure 5 is a forward structural schematic diagram of the self-dredging sand blocking dam structure in the application.

[0043] Figure 6 Figure 6 is a longitudinal sectional structural schematic diagram of the funnel-shaped stopping field structure in the application. Figure 6 Figure 6 (a) is a structural schematic diagram of the funnel-shaped stopping field structure without setting a planting groove, Figure 6 Figure 6 (b) is a structural schematic diagram of the funnel-shaped stopping field structure with a planting groove.

[0044] Figure 7 Figure 7 is a top view structural schematic diagram of the funnel-shaped stopping field structure in the application; the dotted arrow in the figure schematically shows the main flow path of the water flow or mud flow into the funnel-shaped stopping field structure.

[0045] Figure 8Fig. 1 is a schematic diagram of the working principle of water flow passing through the drainage hole of the self-dredging sand dam; the dotted arrow in the figure schematically shows the main flow path of water flow or debris flow passing through the self-dredging sand dam structure.

[0046] Figure 9 Fig. 2 is a schematic diagram of the working principle of water flow passing through the overflow port of the self-dredging sand dam and carrying silt and sand into the funnel-shaped silt storage field structure; the dotted arrow in the figure schematically shows the main flow path of water flow or debris flow passing through the self-dredging sand dam structure.

[0047] Figure 10 Fig. 3 is a schematic diagram of the structure of the steel wire mesh.

[0048] Figure 11 Fig. 4 is a schematic diagram of the state before the steel wire mesh is installed on the vegetation.

[0049] Figure 12 Fig. 5 is a schematic diagram of the state after the steel wire mesh is installed on the vegetation for a period of time.

[0050] Figure 13 Fig. 6 is a schematic diagram of the main flow path of water flow in daily operation after the debris flow automatic shunting and dredging sand-damming and silt storage combined structure is arranged in the river channel; the dotted arrow in the figure schematically shows the main flow path of water flow.

[0051] Figure 14 Fig. 7 is a schematic diagram of the main flow path of debris flow when the debris flow bursts after the debris flow automatic shunting and dredging sand-damming and silt storage combined structure is arranged in the river channel; the solid arrow in the figure schematically shows the main flow path of water flow.

[0052] In the figure:

[0053] 1, crescent-shaped shunting structure; 1.1, circular concrete column; 1.4, square concrete column; 1.5, gabion column;

[0054] 2, self-dredging sand dam structure; 2.1, drainage hole; 2.2, gate; 2.3, overflow port;

[0055] 3, funnel-shaped silt storage field structure; 3.1, inclined slope surface; 3.2, funnel-shaped silt storage pool; 3.3, silt discharge hole;

[0056] 4, vegetation; 4.1, tree; 4.2, vine plant;

[0057] 5, soil and stone mixture;

[0058] 6, planting groove;

[0059] 7, steel wire mesh;

[0060] 9, silt accumulation body;

[0061] 11 natural river channel;

[0062] Hmax is the maximum depth of the debris flow; Hwater is the daily water level; Hdesilt is the desilting water level; Hdam is the height of the designed desilting field; and Hplant is the ecological protection height increased due to the ecological effect of the vegetation in the later stage. DETAILED DESCRIPTION

[0063] The above content of the present application will be further explained in detail in combination with the specific embodiments of the examples. However, it should not be understood that the above-mentioned subject matter of the present application is limited to the following examples. Various substitutions or changes made according to the ordinary technical knowledge and conventional means in the art without departing from the above-mentioned technical idea of the present application should be included in the scope of the present application.

[0064] Example 1

[0065] The channel erosion mechanism is mainly affected by the water flow power, topography and geomorphology and riverbed material composition, and the erosion, transportation and deposition processes determine the evolution mode of the river channel. Figure 1 The water flow state of the natural river channel 11 along the erosion path and the three key cross sections A, B and C is shown. The outer side of the bend is the concave bank, and the inner side of the bend is the convex bank. In the curved river section, the water flow presents a spiral flow motion, and the water flow is faster on the concave bank, the shear force is larger, and the erosion effect is enhanced, resulting in the differentiation of the concave bank erosion and the convex bank deposition.

[0066] The present embodiment provides a debris flow along the channel automatic diversion desilting and sand blocking-stopping combination structure, which comprises at least one automatic diversion desilting and sand blocking-stopping unit arranged at the bend of the river channel.

[0067] As shown in Figure 2 , a certain section of the natural river channel 11 has two bends, and one automatic diversion desilting and sand blocking-stopping unit is arranged at each bend. Each automatic diversion desilting and sand blocking-stopping unit comprises a crescent-shaped diversion structure 1, a self-desilting and sand blocking dam structure 2 and a funnel-shaped desilting field structure 3 arranged in sequence along the water flow direction.

[0068] The crescent-shaped diversion structure 1 is in the shape of a crescent as a whole, is arranged at the entrance of the bend of the river channel along the curved direction of the bend, and the top is covered with vegetation 4. It is used to guide the water flow or debris flow to divert along the set path to reduce the impact on the downstream self-desilting and sand blocking dam structure 2, and also to enhance the self-desilting and anti-scouring capacity.

[0069] The self-desilting and sand blocking dam structure 2 comprises a main dam body transversely arranged on the river channel. It is used to guide the water flow to directly pass through the main dam body to carry away the accumulated body 9 or to enter the funnel-shaped desilting field structure 3 for desilting in normal state, and also to guide the debris flow to smoothly overflow into the funnel-shaped desilting field structure 3 for stopping in the event of a debris flow outbreak.

[0070] Funnel type deposition field structure 3 is arranged on one side close to the convex bank of the river channel, and is used for accumulating debris flow and gradually depositing, converging and discharging the mud and sand in the debris flow through the funnel type structure when the debris flow breaks out.

[0071] During daily operation, the main path of the accumulated sludge and mud sand moving with the water flow is as shown in Figure 13 . When the debris flow breaks out, the main path of a large amount of mud and sand in the debris flow moving with the water flow is as shown in Figure 14 . During daily operation, the sludge and mud sand in the water move with the water flow from between the crescent type diversion structure 1 and the concave bank of the curved channel, and are guided to the inlet of the self-dredging sand dam structure 2. When the debris flow breaks out, the debris flow is diverted by the crescent type diversion structure 1, part of which passes between the crescent type diversion structure 1 and the concave bank of the curved channel, and is guided to the inlet of the self-dredging sand dam structure 2; part of which passes between the crescent type diversion structure 1 and the convex bank of the curved channel, and is intercepted by the self-dredging sand dam structure 2; as the sand dam accumulation increases, the excess debris flow will be deposited in the funnel type deposition pool 3.2 through the overflow port 2.3, and the debris flow size is adjusted through the combined multi-stage automatic diversion dredging sand dam-deposition combined structure. After the debris flow stops, the automatic dredging process of the accumulated body 9 in the self-dredging sand dam structure 2 and the funnel type deposition field structure 3 is realized through the erosion process along the natural river channel.

[0072] Therefore, the added crescent type diversion structure 1 can guide the water flow / debris flow to flow along the set path, reduce the impact on the downstream dam body, and also fully utilize the impact force of the high flow velocity of the concave bank to realize dredging, and enhance the self-erosion capacity and self-dredging capacity.

[0073] Embodiment 2:

[0074] This embodiment is based on embodiment 1, and discloses in detail two typical structures of the crescent type diversion structure 1, as shown in Figure 3 , Figure 4 . Figure 4 Hmax in the formula (1) represents the maximum debris flow mud depth designed, and the main body height of the crescent type diversion structure 1 exceeds the maximum debris flow mud depth designed, forming a barrier in the river channel.

[0075] As shown in Figure 3 (a) and Figure 4 (a), the first typical structure of the crescent type diversion structure 1: the crescent type diversion structure 1 includes a plurality of circular concrete columns 1.1; the plurality of circular concrete columns 1.1 are distributed in a crescent shape and surrounded by impermeable geotextile to form a crescent space, and the crescent space is filled with soil and rock mixture 5.

[0076] As shown in Figure 3 (b) and Figure 4As shown in (b), the typical structure of the second crescent-shaped diversion structure 1 is as follows: the crescent-shaped diversion structure 1 includes square concrete columns 1.4 and gabion columns 1.5; multiple square concrete columns 1.4 and multiple gabion columns 1.5 are staggered and distributed in a crescent shape, and are enclosed by impermeable geotextile to form a crescent-shaped space, which is filled with soil-rock mixture 5.

[0077] The other parts of this embodiment are the same as those in the above embodiments, so they will not be described again.

[0078] Example 3:

[0079] Based on embodiment 1 or 2, this embodiment discloses in detail the structure of the self-dredging and sediment-trapping dam structure 2.

[0080] like Figure 5 As shown, the main dam body of the dredging and sediment retention dam structure 2 has drainage holes 2.1 and overflow outlets 2.3 that connect the upstream and downstream sides. Drainage holes 2.1 are located on the concave bank of the river on the main dam body and are equipped with gates 2.2 that can be opened and closed. When gate 2.2 is open, water flows normally; when gate 2.2 is closed, water is stored. Overflow outlets 2.3 are located on the convex bank of the river on the main dam body and at the top of the main dam body, used to guide water or debris flow towards the funnel-shaped sediment retention pond structure 3.

[0081] The purpose of drainage hole 2.1 is to remove accumulated water in front of the silt-trapping dam and to drain away accumulated silt and sand under the action of water flow, achieving automatic dredging and reducing manual maintenance. Gate 2.2 is located above drainage hole 2.1 and is normally in the open position. Figure 8 As shown, the daily water level Hwater is low. Opening gate 2.2 allows water to flow through drainage hole 2.1, quickly releasing the silt deposited in front of the dam 9, achieving the dam's self-cleaning function and extending its service life. Figure 9 As shown, when gate 2.2 is closed, the water level continuously rises and exceeds the dredging water level Hdesilt. Then, it enters the funnel-shaped sediment retention structure 3 from the overflow outlet 2.3. Under the rotational action of the water flow, the automatic dredging function of the sediment accumulation body 9 in the funnel-shaped sediment retention structure 3 is achieved. Another design purpose of the overflow outlet 2.3 is to ensure the smooth overflow of debris flows under large-scale debris flow conditions, avoiding dam failure due to excessively high water levels. Simultaneously, the multiple-stage funnel-shaped sediment retention structures 3 control and intercept debris flows, reducing their scale flowing downstream and minimizing downstream disaster losses.

[0082] The other parts of this embodiment are the same as those in the above embodiments, so they will not be described again.

[0083] Example 4:

[0084] Based on any one of embodiments 1-3, this embodiment discloses in detail the structure of the funnel-shaped siltation storage structure 3.

[0085] like Figure 6 , Figure 7 As shown, the funnel-shaped sediment retention pond structure 3 includes an inclined slope 3.1, a funnel-shaped sediment retention pond 3.2, and a discharge hole 3.3. The inner cavity of the funnel-shaped sediment retention pond 3.2 is a multi-step spiral shape, wider at the top and narrower at the bottom. The inclined slope 3.1 is located at the inlet at the top of the funnel-shaped sediment retention pond 3.2 and is connected to the overflow outlet 2.3 of the self-dredging and sediment trapping dam structure 2. The discharge hole 3.3 is located at the bottom or side of the funnel-shaped sediment retention pond 3.2.

[0086] like Figure 8 , Figure 9 As shown, the funnel-shaped sediment retention pond structure 3 is connected to the overflow outlet 2.3 of the self-cleaning silt-trapping dam structure 2 to form an integral whole. It consists of an inclined slope 3.1, a funnel-shaped sediment retention pond 3.2, a discharge hole 3.3, and an outer planting trough 6. The purpose is to efficiently intercept and store debris flows through the multi-stage funnel-shaped sediment retention pond structure 3, reducing its scale, and achieving automatic settling and discharge through gravity and hydraulic action. The inclined slope 3.1 is located at the inlet of the overflow outlet 2.3, guiding the debris flow to concentrate in the sediment retention pond and improving sedimentation efficiency. The funnel-shaped sediment retention pond 3.2 is located in the core area of ​​the sediment retention pond. Utilizing its funnel-shaped structure, it allows silt to gradually settle and concentrate at the bottom of the pond, avoiding dispersed siltation and improving discharge efficiency. Furthermore, during the silt retention pond dredging process, it can form a vortex flow, promoting the removal of silt deposits 9. The discharge hole 3.3 is located at the bottom or side wall of the sediment retention pond, using water flow to carry silt out, realizing the self-cleaning function of the sediment retention pond and reducing maintenance requirements.

[0087] like Figure 6 As shown in (a), the funnel-shaped siltation site structure 3 does not have a planting trough 6; as Figure 6 As shown in (b), the funnel-shaped siltation site structure 3 has a planting trough 6 set around the funnel-shaped siltation pond 3.2; the top of the planting trough 6 is covered with vegetation 4 to achieve the coordinated management of soil and rock and ecology and improve its ecological function.

[0088] The other parts of this embodiment are the same as those in the above embodiments, so they will not be described again.

[0089] Example 5:

[0090] Based on any one of embodiments 1-4, this embodiment discloses in detail the structure of the planting trough 6 and the structure of the ecological protection net.

[0091] The planting trough 6 is mainly made of concrete or gabions, and the inside of the trough is filled with a mixture of soil and stone 5.

[0092] In some embodiments, vegetation 4 includes trees 4.1 and vines 4.2. A wire mesh 7 is laid between multiple trees 4.1, and the vines 4.2 climb onto the wire mesh 7 by relying on the branches of the trees 4.1 to form an ecological protection net.

[0093] The structure of wire mesh 7, such as Figure 10 As shown. Before installing the wire mesh 7 in vegetation 4, as... Figure 11 As shown, the height of planting trough 6 in the diagram is designed with reference to the designed sediment retention pond height Hdam. In the early stages, the plants, besides their ecological function, do not possess protective capabilities. As time increases, such as after 3-5 years, after the trees 4.1 have grown, wire mesh 7 is laid between adjacent trees 4.1. Later, with the growth of vines 4.2, it forms a real ecological protective net with the wire mesh 7 and trees 4.1, not only possessing ecological functions but also preventing debris flows from climbing up when the funnel-shaped sediment retention pond structure 3 encounters exceeding standard debris flows, acting as an ecological barrier. The addition of wire mesh 7 to the vegetation 4 increases the ecological protection height Hplant after the vegetation exerts its ecological effect later on. Figure 12 As shown.

[0094] The other parts of this embodiment are the same as those in the above embodiments, so they will not be described again.

[0095] Example 6:

[0096] Based on any one of embodiments 1-5, this embodiment discloses an automatic diversion, dredging, and sediment retention combined structure for debris flows, comprising multiple automatic diversion, dredging, sediment retention, and sediment retention units arranged sequentially along the river's flow direction. Each automatic diversion, dredging, sediment retention, and sediment retention unit includes a crescent-shaped diversion structure 1, a self-dredging sediment retention dam structure 2, and a funnel-shaped sediment retention area structure 3, arranged sequentially along the river's flow direction.

[0097] The first core component of the combined structure is the crescent-shaped diversion structure 1. Located within the river channel, the crescent-shaped diversion structure 1 effectively divides the river flow in two: one portion continues flowing along the main channel, while the other is guided to the entrance of the funnel-shaped sediment retention structure 3. The top of the crescent-shaped diversion structure 1 is planted with vegetation 4. This vegetation 4 not only enhances the stability of the crescent-shaped diversion structure 1 but also stabilizes the soil with its root system, preventing structural damage caused by water erosion. The selection of vegetation 4 primarily considers species with strong local adaptability and well-developed root systems, such as aquatic or wetland plants like willows and reeds. In the event of a debris flow, this vegetation 4 can initially intercept sediment, reducing the burden on subsequent structures.

[0098] The second core part of the combined structure is the self-cleaning debris dam structure 2. The self-cleaning debris dam structure 2 is placed horizontally across the river channel and is built with high-strength concrete or stone blocks, which have sufficient strength to resist the impact force of debris flow. More importantly, the self-cleaning debris dam structure 2 achieves the function of automatically cleaning the accumulated sediment after the debris flow through a unique structural design. Multiple drainage holes 2.1 are provided on the dam body. When the water flow is small, water can flow out through these drainage holes 2.1; when the debris flow comes, a large amount of sediment will be intercepted in front of the dam, while the water flows through the dam and continues to flow. With the continuous erosion of the water flow, the intercepted sediment will gradually be carried away by the water flow, achieving the self-cleaning function. This design avoids the shortcomings of traditional debris dams relying on manual cleaning, greatly reducing maintenance costs and labor input.

[0099] The third core part of the combined structure is the funnel-shaped sedimentation field structure 3. The funnel-shaped sedimentation field structure 3 is connected to the side of the self-cleaning debris dam structure 2 near the convex bank of the river channel. The design inspiration of the funnel-shaped sedimentation field structure 3 comes from the shape of a funnel, with a wide entrance and a narrow exit. When the debris flow passes through the crescent-shaped diversion structure 1, part of the sediment will be guided into the funnel-shaped sedimentation field structure 3. Due to the characteristics of the funnel-shaped structure, the sediment will deposit due to the slowing down of the flow rate after entering. The bottom of the funnel-shaped sedimentation field structure 3 is designed with a gentle slope, which is convenient for cleaning the deposited sediment later. At the same time, a filtering device is provided at the outlet of the funnel-shaped sedimentation field structure 3 to ensure that the water flowing out is relatively clean, reducing the impact on the downstream environment.

[0100] Multiple automatic diversion and cleaning debris dam and sedimentation units are arranged in sequence along the flow direction of the river channel, forming a complete debris flow control system. This cascading arrangement can intercept the sediment in the debris flow in sections, avoiding excessive pressure on a single structure. The first unit intercepts most of the coarse-grained sediment, and the subsequent units are responsible for intercepting finer sediment particles, ultimately achieving effective control of the debris flow.

[0101] In practical application, the distance between each unit of the debris flow diversion and cleaning structure can be adjusted according to factors such as river characteristics, slope, flow, etc. Generally speaking, in the upstream area where the river slope is steep, the distance between units can be relatively close to enhance the interception effect; in the downstream area where the slope is gentle, the distance between units can be appropriately increased.

[0102] The working principle of the debris flow diversion and cleaning structure is as follows: when the debris flow occurs, the crescent-shaped diversion structure 1 first guides part of the debris flow to the funnel-shaped sedimentation field structure 3, reducing the burden on the main river channel; then the self-cleaning debris dam structure 2 intercepts the sediment in the main river channel, allowing only water and a small amount of fine sediment to pass through; finally, the funnel-shaped sedimentation field structure 3 collects and deposits the diverted sediment. The entire process does not require manual intervention and can automatically complete the diversion, interception, and cleaning of the debris flow, effectively protecting the safety of the downstream area.

[0103] Compared with the traditional debris flow prevention measures, the debris flow shunting and dredging structure has the advantages of high automation, low maintenance cost and environmental friendliness, and is particularly suitable for application in debris flow prevention engineering of mountainous river channels with sparse population and poor transportation.

[0104] The other parts of the embodiment are the same as those of the above-described embodiment, and thus will not be described again.

[0105] Embodiment 7:

[0106] The embodiment discloses a construction method of the debris flow along the automatic shunting and dredging sand-stopping combined structure.

[0107] The construction method first selects a site and processes a foundation, and then constructs the crescent-shaped shunting structure 1, the self-dredging sand dam structure 2, the funnel-shaped sand stopping field structure 3, and the vegetation 4 according to the above-described debris flow along the automatic shunting and dredging sand-stopping combined structure, and finally performs trial operation and joint debugging on the automatic shunting and dredging sand-stopping unit after the construction is completed.

[0108] The site selection refers to selecting a debris flow prone area and determining a river bend with strong water flow power and obvious concave bank erosion as a construction area, so as to ensure that the natural water flow can be used for shunting and dredging.

[0109] The foundation treatment refers to cleaning the soft soil layer of the riverbed and both banks in the construction area and reinforcing according to the geological conditions, so as to ensure the stability of the foundation.

[0110] Specifically, the construction method of the debris flow along the automatic shunting and dredging sand-stopping combined structure includes the following steps.

[0111] Step S1, site selection and foundation treatment: selecting a debris flow prone area and determining a river bend with strong water flow power and obvious concave bank erosion as a construction area to ensure that the natural water flow can be used for shunting and dredging; cleaning the soft soil layer of the riverbed and both banks and reinforcing according to the geological conditions to ensure the stability of the foundation and prevent settlement or scouring failure.

[0112] Step S2, construction of the crescent-shaped shunting structure 1: pouring a circular concrete column 1.1, using an abrasion-resistant concrete material, or staggered arranging a square concrete column 1.4 and a gabion column 1.5; filling impermeable geotextile between the concrete columns to reduce permeation damage; filling soil and stone mixture 5 behind the geotextile to enhance the overall stability; planting plants on the surface of the soil and stone mixture 5 to enhance the ecological restoration capacity and provide long-term slope protection.

[0113] In a preferred embodiment, the circular concrete columns 1.1 of the crescent-shaped diversion structure 1 have a diameter of 0.8–1.2 meters, a height of 2–3 meters, and a column spacing of 1.5–2.5 meters. The square concrete columns 1.4 have cross-sectional dimensions ranging from 0.6 meters × 0.6 meters to 1 meter × 1 meter, and the gabion columns 1.5 have a diameter of 0.8–1.5 meters. The impermeable geotextile adopts a double-layer structure, with bentonite filling the middle to enhance the seepage prevention effect.

[0114] Step S3, Construction of the self-dredging sediment trap structure 2: The sediment trap is constructed at a suitable location on the concave bank using reinforced concrete or earth-rock dam to ensure the ability to intercept debris flows; a drainage hole 2.1 is reserved at the lower part of the dam body near the concave bank for daily dredging; a gate 2.2 is installed above the drainage hole 2.1, which is opened daily to remove deposited sediment and can be closed when necessary to raise the water level; an overflow outlet 2.3 is constructed at the upper part of the convex bank to ensure that excessive debris flows can overflow smoothly and be diverted to the sedimentation site.

[0115] In another preferred embodiment, the self-dredging silt-trapping dam is constructed of reinforced concrete with an arc-shaped design, the curvature facing upstream to enhance its impact resistance. The drainage holes 2.1 are designed in multiple layers, with three layers located at 1 / 5, 2 / 5, and 4 / 5 of the dam height, respectively, with 3 to 5 drainage holes 2.1 in each layer, forming a three-dimensional drainage system.

[0116] Step S4, Construction of the funnel-shaped sedimentation pond structure 3: Construct an inclined slope 3.1 below the overflow outlet 2.3 to guide silt into the sedimentation pond and improve sedimentation efficiency; adopt a multi-stage arrangement to form a stepped sedimentation pond to improve sedimentation capacity; reserve silt discharge holes 3.3 at the bottom or side wall of the sedimentation pond to periodically remove silt using water flow dynamics, reducing maintenance requirements.

[0117] In another preferred embodiment, the funnel-shaped sediment retention pond structure 3 adopts a four-stage stepped design, with a total area not less than three times the interception area of ​​the silt-trapping dam, ensuring sufficient sedimentation capacity. Each stage of the sediment retention pond has a 2% reverse slope at the bottom to facilitate the concentration of sediment towards the discharge holes 3.3. The discharge holes 3.3 are equipped with an automatic control system that automatically opens and closes according to the sedimentation thickness.

[0118] Step S5, construction of ecological planting trough 6: Build planting trough 6 around the silt retention pond and fill it with soil and rock mixture 5; plant trees 4.1, and later install wire mesh 7 in between to form an ecological interception net with vine plants 4.2 to improve the debris flow interception capacity;

[0119] Step S6, structure joint debugging and running: after construction is completed, check stability of each structure, ensure that the drainage hole 2.1, overflow 2.3, the silt hole 3.3 and the like function normally; carry out water flow test, observe water flow path, deposition effect and dredging efficiency, optimize the opening mode of the gate 2.2 and the silt hole 3.3; in the debris flow event, monitor the interception and deposition effect of the sand dam and the silt pond, and timely adjust the operation mode of the gate 2.2 and the silt hole 3.3.

[0120] After construction is completed, check stability of each structure, ensure that the drainage hole 2.1, overflow 2.3, the silt hole 3.3 and the like function normally; carry out water flow test, observe water flow path, deposition effect and dredging efficiency, optimize the opening mode of the gate 2.2 and the silt hole 3.3; in the debris flow event, monitor the interception and deposition effect of the sand dam and the silt pond, and timely adjust the operation mode of the gate 2.2 and the silt hole 3.3.

[0121] Through the above construction method, the debris flow along the way automatic shunt dredging sand-stopping and silt combination structure can effectively deal with debris flow disaster, realize the shunt, interception and deposition function of debris flow, at the same time, has self-dredging capacity, reduces the artificial dredging workload, improves the long-term operation efficiency of the system. The structure also has good ecological restoration function, reduces the damage to the natural environment, realizes the organic combination of engineering measures and ecological measures.

[0122] The above is only the preferred embodiment of the present application, not any form of the present application, any simple modification, equivalent change of the above embodiment according to the technical essence of the present application, falls within the scope of the present application.

Claims

1. A combined structure for automatic diversion, dredging and sand blocking along the course of a debris flow, characterized in that: The automatic shunt dredging and sand blocking and stopping unit comprises a crescent-shaped shunt structure (1), a self-dredging sand blocking dam structure (2) and a funnel-shaped stopping field structure (3) arranged in sequence along the water flow direction. ​ The crescent-shaped shunt structure (1) is in a crescent shape as a whole, is arranged at the entrance of a river bend along the bending direction of the river bend, and is covered with vegetation (4) at the top, is used for guiding water flow or debris flow to shunt along a set path to reduce the impact on the self-dredging sand blocking dam structure (2) downstream, and is used for enhancing the self-dredging capacity and the self-dredging capacity. The self-dredging sand blocking dam structure (2) comprises a main dam body arranged horizontally on the river, is used for guiding water flow to directly pass through the main dam body to carry away the accumulated body (9) or to enter the funnel-shaped stopping field structure (3) to dredge in normal times, and is used for guiding debris flow to smoothly overflow into the funnel-shaped stopping field structure (3) to stop in the event of a debris flow outbreak. The funnel-shaped stopping field structure (3) is arranged on the side close to the convex bank of the river, is used for accumulating debris flow and gradually depositing, converging and concentrating the mud and sand in the debris flow to discharge when the debris flow breaks out.

2. The debris flow automatic in-line flow splitting, dredging and sand blocking-retention-stopping combined structure according to claim 1, characterized in that: The crescent-shaped shunt structure (1) comprises a plurality of circular concrete columns (1.1); the plurality of circular concrete columns (1.1) are distributed in a crescent shape and are enclosed by water-impermeable geotextile to form a crescent-shaped space, and the crescent-shaped space is filled with soil and stone mixture (5).

3. The debris flow automatic shunting and dredging sand-blocking and sediment-stopping combined structure along the way according to claim 1, characterized in that: The crescent-shaped shunt structure (1) comprises square concrete columns (1.4) and gabion columns (1.5); the plurality of square concrete columns (1.4) and the plurality of gabion columns (1.5) are arranged alternately and in a crescent shape, and are enclosed by water-impermeable geotextile to form a crescent-shaped space, and the crescent-shaped space is filled with soil and stone mixture (5).

4. The debris flow automatic shunting and dredging sand-blocking-retaining structure along the way according to claim 1, characterized in that: The main dam body of the self-dredging sand blocking dam structure (2) is provided with a drainage hole (2.1) and an overflow port (2.3) capable of communicating the flow face and the back flow face; The drainage hole (2.1) is arranged on the side of the main dam body close to the concave bank of the river, and is provided with a gate (2.2) capable of being opened and closed; the gate (2.2) is opened when the water flow is normal, and the gate (2.2) is closed when the water flow is accumulated; The overflow port (2.3) is arranged on the side of the main dam body close to the convex bank of the river and is located at the upper part of the main dam body, and is used for guiding water flow or debris flow to the funnel-shaped stopping field structure (3).

5. The debris flow automatic shunting and cleaning and sand blocking-stop silting combined structure along the way according to claim 4, characterized in that: The funnel-shaped stopping field structure (3) comprises an inclined slope (3.1), a funnel-shaped stopping pool (3.2) and a dredging hole (3.3); The inner cavity of the funnel-shaped stopping pool (3.2) is in a spiral shape with multiple steps from large at the top to small at the bottom; The inclined slope (3.1) is arranged at the entrance of the top of the funnel-shaped stopping pool (3.2) and is connected with the overflow port (2.3) of the self-dredging sand blocking dam structure (2), The dredging hole (3.3) is arranged at the bottom or side of the funnel-shaped stopping pool (3.2).

6. The debris flow automatic shunting and cleaning and sand blocking-stop silting combined structure along the way according to claim 5, characterized in that: The funnel-shaped stopping field structure (3) further comprises a planting groove (6) arranged on the periphery of the funnel-shaped stopping pool (3.2); and the top of the planting groove (6) is covered with vegetation (4).

7. The debris flow automatic shunting and cleaning and sand blocking-stop silting combined structure along the way according to claim 6, characterized in that: The groove body of the planting groove (6) is mainly made of concrete or stone cage, and the inside of the groove body is filled with soil and stone mixture (5).

8. The debris flow automatic shunting and cleaning and sand blocking-stopping combination structure according to claim 1 or 6, characterized in that: The vegetation includes trees (4.1) and vines (4.2), a plurality of trees (4.1) are arranged with steel wire meshes (7), and the vines (4.2) climb on the branches of the trees (4.1) to the steel wire meshes (7), forming an ecological protection net.

9. The construction method of the debris flow automatic shunting, dredging and sand blocking-stopping combination structure along the way, characterized in that: After site selection and foundation treatment, according to the debris flow along the automatic shunting dredging sand blocking-stopping sediment combination structure according to any one of claims 1-8, a crescent-shaped shunting structure (1) is built, a self-dredging sand blocking dam structure (2) is built, a funnel-shaped stopping sediment field structure (3) is built, and vegetation (4) is covered, and after construction is completed, the automatic shunting dredging sand blocking stopping sediment unit is tested and jointly debugged.

10. The construction method of debris flow along the automatic shunting dredging sand - stop muddy combined structure of claim 9, characterized in that: The site selection and foundation treatment refer to selecting a debris flow prone area, determining a river bend with strong water flow power and obvious concave bank erosion as a construction area, to ensure that the natural water flow can be shunted and dredged; in the construction area, the soft soil layer of the riverbed and the two banks is cleaned, and is reinforced according to the geological conditions, to ensure the stability of the foundation. The groove body of the planting groove (6) is mainly made of concrete or stone cage, and the inside of the groove body is filled with soil and stone mixture (5). The vegetation includes trees (4.1) and vines (4.2), a plurality of trees (4.1) are arranged with steel wire meshes (7), and the vines (4.2) climb on the branches of the trees (4.1) to the steel wire meshes (7), forming an ecological protection net.

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