A protection system for riverbank spoil sites in steep mountainous areas and its construction method

Abstract

The present invention relates to a protection system for river beach abandoned soil sites in steep mountainous areas. The protection system for river beach abandoned soil sites in steep mountainous areas includes an upstream retaining wall, a downstream retaining wall, and a drainage system; the upstream retaining wall and the downstream retaining wall are both composite retaining walls, the dam bottom is a gravity retaining wall, and the back of the wall is divided into multiple levels of slag piles; the drainage system includes an intercepting ditch arranged along one side of the abandoned soil site close to the mountain body, a flood discharge ditch arranged along the other side of the abandoned soil site close to the mountain body, a blind ditch arranged at the bottom of the abandoned soil site and arranged along the original river ditch, and a flood discharge tunnel arranged in one side of the mountain body for diverting upstream water to a natural river channel. The protection system for river beach abandoned soil sites in steep mountainous areas can effectively improve the stability of the abandoned soil site and is not prone to mudslides. The present invention also relates to a construction method for a protection system for river beach abandoned soil sites in steep mountainous areas.

Description

Technical Field

[0001] The invention relates to the technical field of engineering waste slag treatment, in particular to a protection system for river beach waste dumps in steep mountainous areas, and a construction method of the protection system. Background Art

[0002] The geological environment of mountain highways is complex, and the terrain is undulating. No matter what construction plan is adopted, a large amount of waste will be generated. In addition, the mountains along the route are high and the slopes are steep, so there are few sites suitable for waste soil. The waste soil sites are either located in gullies with large water volume, on slopes, or on river beaches with small water volume. The unreasonable stacking of waste soil and waste rocks generated during the construction process will damage the original environment, and it is easy to cause various secondary disasters such as mudslides due to the unreasonable setting of waste soil sites. Summary of the invention

[0003] In view of this, it is necessary to provide a protection system for river beach waste dumps in steep mountainous areas and a construction method of the protection system in response to the above-mentioned problems.

[0004] In a first aspect, the present invention provides a system for protecting riverbank waste dumps in steep mountainous areas.

[0005] The protection system of the river beach spoil field in the steep mountainous area includes an upstream retaining wall, a downstream retaining wall, and a drainage system;

[0006] The upstream retaining wall is set at the front edge of the spoil field, and the dam bottom is a gravity retaining wall. The back of the wall is divided into multiple levels of slag piles. The first level of the slope includes a cement mortar cushion layer, a geomembrane, a sand layer, and a gravel layer arranged from bottom to top, and adopts prefabricated concrete column blocks for slope protection. Each level of the upper slope adopts a concrete frame beam and grass planting for slope protection, and a horse path is set between each level of the slope;

[0007] The downstream retaining wall is set at the rear edge of the spoil field, the dam bottom is a gravity retaining wall, the back of the wall is divided into multiple levels of slag, the first level of slope is protected by dry block stone, each level of upper slope is protected by concrete frame beams and grass, and a horse path is set between each level of slope;

[0008] The drainage system includes an intercepting ditch set along one side of the spoil site close to the mountain, a flood discharge ditch set along the other side of the spoil site close to the mountain, a blind ditch set at the bottom of the spoil site and arranged along the original river ditch, and a flood discharge tunnel set in one side of the mountain for diverting upstream water to the natural river channel.

[0009] Optionally, the blind ditch includes a concrete foundation, a circular culvert arranged on the concrete foundation, and a slab-stone blind ditch paved with slabs arranged on both sides of the concrete foundation.

[0010] Optionally, the bottom of the sheet stone blind ditch is located below the original ditch bottom, and the bottom of the inner hole of the circular culvert is located at the same horizontal plane as the original ditch bottom.

[0011] Optionally, the water inlet of the flood discharge tunnel adopts a pressure-free tunnel design, and the water outlet of the flood discharge tunnel is provided with an underflow stilling pool.

[0012] Optionally, the intercepting ditch and the flood drainage ditch are both provided with dividing joints, and the joints are filled with asphalt wooden boards.

[0013] Optionally, the steep mountain river beach spoil dump protection system further comprises a ditch bottom clear clay layer covering the top surface of the spoil dump slope.

[0014] In a second aspect, the present invention provides a construction method for a protection system for a river beach waste dump in a steep mountainous area as described in the first aspect.

[0015] The construction method comprises the following steps:

[0016] S1. Remove the humus and cultivated soil on the original surface and pile them on one side of the abandoned soil field for protection, so as to be used for the later greening project and the restoration of the abandoned soil field;

[0017] S2. Level the base of the abandoned soil field and construct a blind ditch at the base of the abandoned soil field;

[0018] S3. Construction of upstream retaining wall and downstream retaining wall;

[0019] S4, construction of flood discharge tunnel;

[0020] S5, the abandoned soil and slag in the abandoned soil and slag field shall be filled and compacted in layers;

[0021] S6. Construction of intercepting ditches and flood drainage ditches;

[0022] S7. Recultivate and reforest abandoned land.

[0023] The invention discloses a protection system for a river beach abandoned soil field in a steep mountainous area. The invention adopts a composite retaining wall, and arranges intercepting ditches and flood discharge ditches on the ground surface, blind ditches on the base, flood discharge tunnels and other three-dimensional drainage systems on one side of the mountain, and adopts reasonable slope protection to form a comprehensive protection system for the abandoned soil field, which can effectively improve the stability of the abandoned soil field and is not easy to cause mud and rock flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The included drawings are used to provide a further understanding of the embodiments of the present application, which constitute a part of the specification, are used to illustrate the implementation methods of the present application, and together with the text description, explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0025] Figure 1 It is a plan layout diagram of an exemplary embodiment of a protection system for riverbank spoil sites in steep mountainous areas of the present invention;

[0026] Figure 2 for Figure 1 Longitudinal section layout of the middle and upper reaches of the retaining wall;

[0027] Figure 3 for Figure 1 The general drawing of the grass-planted slope protection of the medium concrete frame beam;

[0028] Figure 4 for Figure 1 Schematic diagram of the structure of the middle blind ditch;

[0029] Figure 5 for Figure 1 Longitudinal section of the inlet and outlet of the middle flood discharge tunnel.

[0030] Explanation of the reference numerals: 1. upstream retaining wall; 2. downstream retaining wall; 3. gravity retaining wall; 4. first-level slope; 5. horseway; 6. concrete frame; 7. double beams; 8. intercepting ditch; 9. flood discharge ditch; 10. blind ditch; 11. flood discharge tunnel; 12. concrete foundation; 13. circular culvert; 14. stone blind ditch; 15. bottom flow stilling pool. DETAILED DESCRIPTION

[0031] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0032] In the description of the present invention, it is necessary to understand that the orientations or positional relationships indicated by terms such as “center”, “up”, “down”, “top”, “bottom”, “inside” and “outside” are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0033] Project Overview: The LJ20 contract section of the Sichuan Jiuzhaigou (Gansu-Sichuan border) to Mianyang highway subgrade civil engineering project is located in the Mupi Tibetan Township and Long'an Town of Pingwu County, Mianyang City. The total length of the line is 7.705 kilometers, of which the bridge-tunnel ratio is 100%, and the planned abandoned earthwork is about 1.9 million m 3 , an area of ​​about 80,000 m 2 .

[0034] According to the proportion of bridges and tunnels in the project, the amount of abandoned earthwork, and local terrain conditions, choose Figure 1 The dry river beach at the junction of the two rivers is selected as the site of this abandoned soil site. Combined with the actual topographic and geological conditions of the river beach, the abandoned soil site adopts a full-section pile plan.

[0035] Figures 1 to 5The protection system of the river beach spoil field in steep mountainous area shown in the figure is the protection system of the above spoil field. The protection system of the river beach spoil field in steep mountainous area includes an upstream retaining wall 1, a downstream retaining wall 2 and a drainage system.

[0036] The upstream retaining wall 1 is arranged at the front edge of the spoil field. Figure 2 As shown, the upstream retaining wall adopts a composite retaining wall, the dam bottom is a gravity retaining wall 3, the back of the wall is divided into multiple levels of slag piles, the first level of slope 4 includes a cement mortar cushion layer, a geomembrane, a sand layer, and a gravel layer arranged from bottom to top, and prefabricated concrete columns are used for slope protection, each level of the upper slope adopts concrete frame beams and grass planting for slope protection, and a horseway 5 is set between each level of the slope.

[0037] In this embodiment, the gravity retaining wall of the upstream retaining wall is 6m high, 1.5m wide, the wave ratio of the water-facing slope is 1:0.35, the back of the wall is multi-level slag piled according to the wave ratio of 1:3, the first level slope is 5m high, each level of the upper slope is 8m high, and the horseway is 4m wide. The cement mortar cushion layer is 10cm thick, and the geomembrane model is 500g / m 2 The sand layer is 5 cm thick, the gravel layer is 5 cm thick; the prefabricated concrete column block is a prefabricated hexagonal block with a thickness of 10 cm. It should be understood that the upstream retaining wall can also use other suitable size parameters according to actual conditions.

[0038] The downstream retaining wall is arranged at the rear edge of the spoil dump. The downstream retaining wall is a composite retaining wall. The dam bottom is a gravity retaining wall. The back of the wall is divided into multiple levels of slag piles. The first level of slope is protected by dry block stones. Each level of the upper slope is protected by concrete frame beams and grass. A horse path is set between each level of slope.

[0039] In this embodiment, the gravity retaining wall of the downstream retaining wall is 7.5m high, 2m wide at the top, with multi-level slag piles at a wave ratio of 1:3 on the back of the wall, the first level of slope is 5m high, each level of slope on the upper part is 8m high, the bridleway is 4m wide, and the dry block stone slope protection is 30cm thick. It should be understood that the downstream retaining wall can also use other suitable size parameters according to actual conditions.

[0040] See also Figure 3 In this embodiment, the concrete frame 6 is a C25 concrete frame with a size of 30*30 cm. A set of double beams 7 is arranged every 13.03 m along the dam axis. A gap is arranged between the double beams 7 and filled with asphalt wood boards. It should be understood that the concrete frame beams can also adopt other suitable size parameters.

[0041] Return now Figure 1 The drainage system includes a diversion ditch 8 arranged along one side of the spoil site close to the mountain, a flood discharge ditch 9 arranged along the other side of the spoil site close to the mountain, a blind ditch 10 arranged at the bottom of the spoil site and along the original river ditch, and a flood discharge tunnel 11 arranged in one side of the mountain for diverting upstream water to the natural river channel.

[0042] The intercepting ditch and flood drainage ditch are mainly used to intercept the surface runoff flowing to the spoil site, protect the spoil site from being eroded by water flow, and guide the water to the natural river or ditch outside the spoil site. In this embodiment, the intercepting ditch and flood drainage ditch are split every 10m, with a seam width of 2cm, and asphalt wood boards are used to fill the seams. The other dimensions of the intercepting ditch and flood drainage ditch refer to the relevant specifications of soil and water conservation and the Sichuan Province Storm Flood Calculation Manual, as well as the local previous precipitation conditions. The design flood standard is calculated based on the 30-year storm condition.

[0043] See now Figure 4 The blind ditch is used to divert the water in the river ditch in the early stage and to drain the seepage water in the abandoned soil field in the later stage. It includes a concrete foundation 12, a circular culvert 13 arranged on the concrete foundation 12, and a sheet stone blind ditch 14 paved with sheet stones arranged on both sides of the concrete foundation 12. Specifically, the bottom of the inner hole of the circular culvert is at the same horizontal plane as the original ditch bottom, and the bottom of the sheet stone blind ditch is 30 mm below the original ditch bottom.

[0044] In this embodiment, the circular culvert is a Φ150mm reinforced concrete circular culvert; the bottom of the stone blind ditch is 30mm lower than the original ditch bottom, the stone blind ditch is 120mm high, 100mm wide, and the outer side slope ratio is 1:0.5. It should be understood that the blind ditch can also adopt other suitable size parameters.

[0045] In this embodiment, the flood discharge tunnel is designed for a flood standard of once in 100 years, with a designed peak flow of 153m / s. The tunnel is 366.53m long, with a designed longitudinal gradient of 0.027, a gate-shaped cross-section, and reinforced concrete lining. The energy dissipation facility is designed for a flood standard of once in 30 years, with a designed peak flow of 108m / s. Figure 5 The tunnel inlet is designed as a pressure-free tunnel. The tunnel inlet section has a bottom width of 7m and a height of 7m. The tunnel body section has a bottom width of 7m and a height of 7m. The design flow is 153m / s. The maximum water depth before the culvert is 5m. The roughness coefficient of the tunnel lining is 0.025. The tunnel outlet enters the river after dissipating energy in the bottom flow stilling pool 15.

[0046] In this embodiment, the protection system for the river beach spoil field in steep mountainous areas also includes a ditch bottom clear clay layer covering the top surface of the spoil field slope to seal the top surface of the spoil field slope, thereby achieving three-dimensional drainage of the spoil field with upper sealing and lower drainage.

[0047] The construction method of the steep mountain river beach spoil field protection system comprises the following steps:

[0048] S1. Remove the humus and cultivated soil on the original surface and pile them on one side of the abandoned soil field for protection, so as to be used for the later greening project and the restoration of the abandoned soil field;

[0049] S2. Level the base of the abandoned soil field and construct a blind ditch at the base of the abandoned soil field;

[0050] S3. Construction of upstream retaining wall and downstream retaining wall;

[0051] S4. Construction of flood discharge tunnels should be completed before the rainy season arrives;

[0052] S5, the abandoned soil and slag in the abandoned soil and slag field shall be filled and compacted in layers;

[0053] S6. Construction of intercepting ditches and flood drainage ditches;

[0054] S7. Recultivate and reforest the abandoned soil site. After the site is formed, the slopes, platforms and top surfaces of the site will be greened with grass, shrubs and other plants to restore the ecological environment as soon as possible.

[0055] The present embodiment provides a protection system for a river beach dump in a steep mountainous area. The composite retaining wall is used, and intercepting ditches and flood discharge ditches are arranged on the surface, blind ditches are arranged on the base, and a flood discharge tunnel is arranged on one side of the mountain. A three-dimensional drainage system is provided, and reasonable slope protection is adopted to form a comprehensive protection system for the dump, which can effectively improve the stability of the dump and is not easy to cause mud and rock flow.

[0056] The above-mentioned embodiments only express some implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A protection system for riverbank spoil sites in steep mountainous areas, characterized by: Including upstream retaining wall, downstream retaining wall, drainage system; The upstream retaining wall is set at the front edge of the spoil field, and the dam bottom is a gravity retaining wall. The back of the wall is divided into multiple levels of slag piles. The first level of the slope includes a cement mortar cushion layer, a geomembrane, a sand layer, and a gravel layer arranged from bottom to top, and adopts prefabricated concrete column blocks for slope protection. Each level of the upper slope adopts a concrete frame beam and grass planting for slope protection, and a horse path is set between each level of the slope; The downstream retaining wall is set at the rear edge of the spoil field, the dam bottom is a gravity retaining wall, the back of the wall is divided into multiple levels of slag, the first level of slope is protected by dry block stone, each level of upper slope is protected by concrete frame beams and grass, and a horse path is set between each level of slope; The drainage system includes a ditches arranged along one side of the spoil field close to the mountain, a flood discharge ditch arranged along the other side of the spoil field close to the mountain, a blind ditch arranged at the bottom of the spoil field and along the original river ditch, and a flood discharge tunnel arranged in one side of the mountain for diverting upstream water to the natural river channel; The upstream retaining wall has a water-facing slope wave ratio of 1:0.35, and the back of the wall is multi-staged with slag according to a wave ratio of 1:3; the back of the downstream retaining wall has a multi-staged with slag according to a wave ratio of 1:3; The blind ditch comprises a concrete foundation, a circular pipe culvert arranged on the concrete foundation, and a slab stone blind ditch formed by paving slab stones arranged on both sides of the concrete foundation; The intercepting ditch and the flood drainage ditch are both provided with dividing joints, and the joints are caulked with asphalt wooden boards.

2. The protection system for riverbank spoil sites in steep mountainous areas according to claim 1 is characterized by: The bottom of the sheet stone blind ditch is located below the original ditch bottom, and the bottom of the inner hole of the circular culvert is located at the same horizontal plane as the original ditch bottom.

3. The protection system for riverbank spoil sites in steep mountainous areas according to claim 1 is characterized by: The water inlet of the flood discharge tunnel adopts a pressure-free tunnel design, and the water outlet of the flood discharge tunnel is provided with an underflow stilling pool.

4. The protection system for riverbank spoil sites in steep mountainous areas according to claim 1 is characterized by: It also includes the clear clay layer at the bottom of the ditch covering the top surface of the slope of the abandoned soil field.

5. The protection system for riverbank spoil sites in steep mountainous areas according to any one of claims 1 to 4, characterized in that: The gravity retaining wall of the upstream retaining wall is 6m high, 1.5m wide at the top, 5m high at the first level of slope, 8m high at each level of slope at the top, and 4m wide at the bridleway; the gravity retaining wall of the downstream retaining wall is 7.5m high.

6. The protection system for riverbank spoil sites in steep mountainous areas according to claim 5 is characterized by: The thickness of the cement mortar cushion layer is 10 cm, and the geomembrane model is 500 g / m 2 The sand layer is 5cm thick and the gravel layer is 5cm thick; the precast concrete column blocks are precast hexagonal blocks with a thickness of 10cm.

7. The construction method of the protection system of river beach spoil field in steep mountainous area according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1. Remove the humus and cultivated soil on the original surface and pile them on one side of the abandoned soil field for protection, so as to be used for the later greening project and the restoration of the abandoned soil field; S2. Level the base of the abandoned soil field and construct a blind ditch at the base of the abandoned soil field; S3. Construction of upstream retaining wall and downstream retaining wall; S4, construction of flood discharge tunnel; S5, the abandoned soil and slag in the abandoned soil and slag field shall be filled and compacted in layers; S6. Construction of intercepting ditches and flood drainage ditches; S7. Recultivate and reforest abandoned land.

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