Terrace type debris flow gully slope protection structure

Abstract

The utility model relates to a terrace type debris flow gully slope protection structure, and relates to the technical field of water conservancy projects. The slope surface of the debris flow gully slope is provided with multiple stages of counter-slope terraces from the bottom end to the top end, the terrace structures are distributed at intervals from bottom to top along the contour line, each stage of counter-slope terrace is composed of a terrace surface, a masonry retaining wall and a drainage ditch, hierarchical separation is achieved through the retaining wall, and the terrace surface is covered with a slope native soil layer. And the field ditch is connected with the next stage of terraced field ridge by adopting a mortar rubble material. The field surface has a reverse slope inclination angle of 5-10 degrees, and crops can be planted on the field surface. The field ditches are communicated with main drainage ditches on the two sides of the terrace along the contour line downwards, and metal gates are arranged at the joints to control water flow, are closed when water storage is needed and are opened when water drainage is needed. The structure can effectively reduce the material, construction and maintenance cost, has high debris flow resistance, can stabilize the debris flow channel slope, reduces the water and soil loss of the slope, plays a role in terrace water storage and drainage, and further protects and promotes the growth of crops.

Description

Technical Field

[0001] This application relates to the technical field of slope treatment, and particularly to a terraced debris flow gully slope protection structure. Background Art

[0002] Debris flow is one of the most common and harmful geological disasters in mountainous areas. Due to its sudden outbreak, fast movement speed, huge energy, and strong destructiveness, it often causes great harm to mountainous towns, transportation trunk lines, people's lives and property, and industrial production. In debris flow-prone areas, effective slope protection structures are needed to reduce the destructive impact of debris flows. Traditional slope support structure types such as gravity retaining walls, counterfort retaining walls, cantilever supports, row-pile type anchor bolt retaining wall supports, shotcrete support, and slope ratio method are widely used in debris flow slope protection treatment, for example, to prevent: preventing mountain rock fragments from sliding, preventing roadbed collapse, preventing river channel diversion, protecting the slope of drainage ditches, protecting the slope of debris flow gullies, etc. However, these traditional slope protections have problems such as high material, construction, and maintenance costs, and limited anti-debris flow ability. Therefore, new slope protection technologies need to be developed to solve these problems. In addition, most debris flow-prone areas have a hot and dry valley climate, with hot and less rainy weather, a fragile ecological environment, serious soil erosion, and debris flow disasters are likely to be triggered during short-term heavy rainfall in summer. Therefore, a new terraced structure with drainage and water storage functions should be introduced, which can not only play the role of slope protection but also is beneficial to the growth and development of crops. Summary of the Invention

[0003] In order to reduce the occurrence of collapses and landslides that are not likely to occur on the slopes of debris flow gullies, reduce soil erosion, and at the same time promote the growth of crops, this application provides a terraced debris flow gully slope protection structure.

[0004] The terraced debris flow gully slope protection structure provided by this application adopts the following technical solutions:

[0005] A stepped debris flow gully slope protection structure, characterized in that multiple stepped reverse slopes are arranged on the slope surface of the debris flow gully from the bottom end to the top end. The stepped structures are distributed at intervals along the contour line from bottom to top. Each stepped reverse slope consists of a field surface, a masonry retaining wall and a drainage ditch, and the hierarchical separation is realized through the retaining wall. There is a planting groove above the retaining wall as a ridge, and the planting groove can be used to plant vine plants to cover the retaining wall. The field surface is covered with the original soil layer of the slope, and the drainage ditch is connected to the retaining wall of the next-level terrace using masonry materials. The field surface is designed with a reverse slope inclination angle of 5° to 10°, and crops are suitable for planting on the field surface. The drainage ditch is connected to the main drainage ditch along the contour line downward on one side of the terrace. A metal gate is set at the connection to control the water flow, which is closed when water storage is required and opened when draining to achieve the functions of water storage and drainage. The structural design of this application can stabilize the slope of the debris flow gully, reduce soil and water loss on the slope, and play the role of water storage and drainage for the terraces. According to the statistical terrace size data in Lianshui Town, Wudu District, Longnan City, Gansu Province, and the local hydrological and meteorological conditions, the following size design is adopted for the terraces of this structure:

[0006] Optionally, the cross-sectional shape of the drainage ditch is rectangular, the top width of the drainage ditch is between 20 cm and 30 cm, the bottom width of the field ditch is between 20 cm and 30 cm, and the depth of the field ditch is between 20 cm and 30 cm.

[0007] Optionally, the width of the planting groove above the ridge is between 25 cm and 30 cm, and the height of the ridge is between 15 cm and 20 cm.

[0008] Optionally, the included angle between the retaining wall and the horizontal plane is between 70° and 80°, and the bottom width of the retaining wall is between 60 cm and 80 cm. Drainage holes with a diameter of 5 cm are evenly arranged at intervals of 40 cm to 50 cm in the retaining wall, and a filter screen is provided at the connection between the back of the drainage hole and the soil mass.

[0009] Optionally, the reverse inclination angle of the field surface is between 5° and 10°, and the width of the field surface can be selected according to the slope of the slope. For slopes of 30° to 45°, it can be 2 m to 4 m, and for slopes of 20° to 30°, it can be 4 m to 8 m.

[0010] By adopting the above technical solution, the stepped surface forms an inclined plane, which can effectively prevent the soil and water on the stepped surface from flowing easily towards the slope body during rainy weather, thereby achieving the purpose of soil fixation and water conservation.

[0011] Optionally, it further includes a main drainage ditch, which is arranged on the slope surfaces on both sides of the stepped reverse slope along the direction perpendicular to the contour line.

[0012] Optionally, the gate is located at the connection between the drainage ditch and the main drainage ditch, and the gate has the same width as the drainage ditch and is lifted and lowered in a rotary manner.

[0013] By means of the above measures, the sluice gate is closed during drought and little rain to store water and maintain the field water holding capacity; after heavy rainfall, the sluice gate is opened in time to drain water, so as to avoid adverse geological disasters caused by rainwater flooding on the slope.

[0014] Optionally, the height difference between the field surfaces of two adjacent levels of the terraced structure is between 2m and 2.2m.

[0015] By adopting the above technical solution, not only the stability of the slope body of the debris flow ditch is realized, but also the scouring of sediment is effectively prevented, so as to effectively fix the slope soil and prevent the sliding deformation of the shallow soil layer.

[0016] In summary, the present application includes the following beneficial technical effects:

[0017] By setting multi-level reverse slope terraces on the slopes of the slope bodies on both sides of the debris flow ditch, the transformation of sloping farmland is realized. The multi-level terrace structures are arranged in sequence along the direction perpendicular to the contour line to transform the sloping farmland into terraces, thereby reducing soil erosion and promoting crop yield increase. Crops are planted on the terrace surface of the reverse slope terrace, and the roots of the crops help to fix the soil and retain moisture. In addition, a drainage ditch is provided at the rear end of the field surface, and the drainage ditch is connected to the main drainage ditch through a sluice gate, which can play the role of draining and storing water. In hot and dry seasons with little rain, the reverse slope terrace can close the sluice gate, converge the runoff into the drainage ditch, collect and store the precipitation, and then store and collect the precipitation through the drainage ditch, so that the precipitation is fully utilized, and the loss of soil and nutrients can be effectively prevented. In the case of short-term heavy rainfall, the reverse slope terrace can open the sluice gate in time during short-term heavy rainfall, and timely discharge the water coming from the slope surface into the debris flow ditch through the main drainage ditch, so as to reduce the damage of the runoff to the terrace structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a structural sectional view of the terraced slope protection of the debris flow ditch in the present application.

[0019] Figure 2 is a structural top view of the terraced slope protection of the debris flow ditch in the present application.

[0020] Description of the reference numerals: 1, retaining wall; 2, ridge; 3, drainage hole; 4, filter screen; 5, field surface; 6, drainage ditch sluice gate; 7, drainage ditch; 8, soil baffle. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] The following is a further detailed description of the present application in conjunction with Figure 1 and Figure 2 to further illustrate the present application in detail.

[0022] The embodiment of the present application discloses a terraced slope protection structure for a debris flow ditch slope.

[0023] Reference Figure 1 The terraced slope protection structure of the debris flow channel slope includes a slope body, on the slope surface of the slope body, there are arranged multiple levels of reverse slope terraces arranged from the bottom of the slope body to the top of the slope body, and a planting trough 2 is arranged at the edge of the highest point of the terrace surface 5 of each layer of the reverse slope terrace, that is, at the ridge above the retaining wall, and vines are planted inside the planting trough 2, so that the vines hang down and cover the surface of the retaining wall below, playing the role of greening and preventing rainwater erosion. The vines that can be selected include single or multiple plants such as red yew, bougainvillea of ​​foreign ivy, wood fragrance, perfume rose, winter jasmine, honeysuckle, golden cup vine, etc., which have the characteristics of high survival rate, strong environmental adaptability, good vine spreading, etc., and can effectively play the role of greening the slope body and reducing rainwater erosion.

[0024] Each layer of the reverse slope terrace field surface 5 is covered and compacted by the original soil of the slope. By covering and compacting, the construction of the reverse slope terrace retaining wall 1, the terrace surface 5 and the planting trough 2 on the slope can be strengthened to ensure the plant planting conditions on the mountain slope, thereby improving the slope protection effect of the slope.

[0025] A drainage ditch 7 is provided at the lowest point of the terrace 5, and a mortar-stone material is used for anti-seepage treatment. The height of the ridge 2 of each layer of the terrace 5 of the reverse slope terrace is higher than the height of the drainage ditch 7. The greater the inclination angle of the field surface 5, the easier it is for precipitation to flow into the drainage ditch 7. However, the inclination angle should not be too large to avoid affecting the stability of the terrace structure. Therefore, the inclination angle of the terrace 5 is preferably 8°. Crops are planted on the surface of the terrace.

[0026] Drain holes 3 with a diameter of 5 cm are evenly arranged at intervals of 40 cm to 50 cm in the retaining wall 1, and a filter screen 4 is provided at the connection between the drainage holes 3 and the soil. When encountering heavy rainfall, the drainage holes can discharge the saturated water in the soil in the field surface 5 in time and flow into the drainage ditch 7 after the next terrace to improve the drainage efficiency. The filter screen 4 can filter large particles in the water to prevent the drainage holes 3 from being blocked.

[0027] The knob gate 6 is located at the junction of the drainage ditch 7 and the main drainage ditch 9. The gate adopts a knob lifting design. One end of the valve shaft is connected to the gate plate, and the other end is connected to the knob handle through a thread, which converts the rotary motion into a linear lifting of the gate plate. The knob above the rotating gate can realize the opening and closing operation of the gate. In drought and little rain, closing the gate can play a role in water storage to maintain the water holding capacity of the field. After heavy rainfall, opening the gate in time can discharge water to the bottom of the slope and then merge into the debris flow ditch to avoid rainwater flooding and cause adverse geological disasters on the slope.

[0028] The location of the main drainage ditch 9 should be selected according to local conditions in combination with the hillside terrain conditions, and it should be selected at the valley or gully position. The interval of the main drainage ditch 9, that is, the length of the terraced field surface, should not exceed 10 m to ensure the drainage efficiency of the drainage ditch 7 and prevent the untimely drainage from affecting the structural stability.

[0029] The drainage ditch 7 is provided with a slope of 5° and slopes towards the drainage ditch 9 to ensure that the water in the drainage ditch 7 flows by gravity into the main drainage ditch 9.

[0030] The soil barriers 8 are located on both sides of the field surface 5 and are arranged along the width direction to form a water storage unit to prevent the water accumulated on the field from flowing out to both sides.

[0031] The content of this application is not limited to the examples listed. Any equivalent transformation of the technical solution of this application by those of ordinary skill in the art by reading the specification of this invention shall be covered by the claims of this application.

Claims

1. A terraced debris flow ditch slope protection structure, comprising a debris flow ditch bank slope, characterized in that: The slope surface of the debris flow ditch is provided with multiple reverse slope terraces from the bottom to the top. The terrace structure is spaced from bottom to top along the contour line. Each reverse slope terrace consists of a field surface, a mortar-laid stone retaining wall and a drainage ditch, and the level separation is achieved by the retaining wall. A planting trough is provided above the retaining wall as a ridge. Vines can be planted in the planting trough to cover the retaining wall. The field surface is covered with the original soil layer of the slope. The drainage ditch is connected to the retaining wall of the next terrace with mortar-laid stone materials. The field surface has a reverse slope inclination of 5° to 10°, and crops can be planted on the field surface. The drainage ditch is connected to the main drainage ditch along the contour line on one side of the terrace. A metal gate is provided at the connection to control the water flow, which is closed when water storage is required and opened when drainage is required.

2. A terraced debris flow ditch slope protection structure according to claim 1, characterized in that: A knob-type gate (6) is provided at the connection between the drainage ditch (7) and the main drainage ditch (9), and the gate can be opened or closed to control whether the water stored on the field surface is discharged.

3. The terraced debris flow ditch slope protection structure according to claim 1, characterized in that: The height of the front ridge of each reverse slope terrace is higher than the height of the rear drainage ditch, so that the terrace surface of each reverse slope terrace is an inclined slope, and the formed slope angle is 5° to 10°.

4. The terraced debris flow ditch slope protection structure according to claim 1, characterized in that: Each layer of reverse slope terrace is separated by a mortar-masonry retaining wall, the angle between the retaining wall and the horizontal plane is between 70° and 80°, the bottom width of the retaining wall is between 60cm and 80cm, the retaining wall has drainage holes with a diameter of 5cm evenly arranged at intervals of 40cm to 50cm, and a filter is provided at the connection between the drainage holes and the soil.

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