A drainage system and construction method for a slope-type spoil ground

Abstract

The application provides a slope type waste dump drainage system and a construction method. The drainage system comprises a surface drainage system, a shallow drainage system and a deep drainage system. The surface drainage system comprises a water intercepting ditch and a plurality of horse paths. The water intercepting ditch is arranged around the edge line of the waste dump. The horse paths are arranged across the surface of the waste dump. The inner side of the horse paths is provided with a horse path drainage ditch. The shallow drainage system comprises a plurality of deep intercepting drainage channels and drainage blind trenches. The deep intercepting drainage channels are arranged below the ground surface line of the waste dump in a horizontal and vertical staggered manner. The deep drainage system comprises drainage holes. The drainage holes are arranged below the lower limit of the strong weathering zone and are distributed in a zigzag shape. A plurality of deep drainage holes are arranged in the drainage holes. The surface drainage system composed of the water intercepting ditch and the horse path drainage ditch, the shallow drainage system composed of the deep intercepting drainage channels and the drainage blind trenches and the deep drainage system composed of the drainage holes and the deep drainage holes are combined in a manner of high efficiency and rapidity to reduce the underground water level line and discharge the surface seepage, thereby effectively ensuring the stability of the waste dump.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of environmental engineering, in particular to a slope type waste dump drainage system and construction method. BACKGROUND

[0002] Generally, large civil engineering projects need to set up large waste dumps. According to geological and topographical conditions, relative position to river, flood treatment mode and other factors, waste dumps can be divided into ditch type, river bank type, slope type, flat type and reservoir area type. For general slope type waste dumps, generally only the slope stability under rainstorm working conditions needs to be considered. Therefore, generally, after taking anti-skid measures at the end of the waste dump, horizontal and vertical interlaced surface layer drainage ditches are arranged on the surface of the waste dump to reduce the influence of surface seepage on the slope of the waste dump, so as to ensure the stability of the whole waste dump. However, for the slope waste dump with deep overburden and high underground water level, seepage in the waste body under rainstorm working conditions is difficult to drain out in a short time, and the high underground water level, underground gushing water and surface seepage easily lead to slope instability of the waste dump. SUMMARY

[0003] The first object of the present application is to provide a slope type waste dump drainage system to solve the above-mentioned problems.

[0004] To achieve the above object, the present application adopts the following technical scheme:

[0005] A slope type waste dump drainage system, comprising a surface drainage system, a shallow drainage system and a deep drainage system, the surface drainage system comprising a water intercepting ditch and a plurality of horse paths, the water intercepting ditch being arranged around the edge line of the waste dump, the horse paths being arranged across the surface of the waste body, the inner side of the horse paths being provided with horse path drainage ditches, the two ends of the horse path drainage ditches being connected with the water intercepting ditch;

[0006] The shallow drainage system comprises a plurality of deep intercepting drainage channels and drainage blind trenches, the deep intercepting drainage channels being arranged horizontally and vertically below the ground surface line and above the lower limit of the weathered zone, the deep intercepting drainage channels being connected with the drainage blind trenches, the end of the deep intercepting drainage channels being connected with the drainage steel pipe;

[0007] The deep drainage system comprises a drainage hole, the drainage hole being arranged below the lower limit of the strong weathered zone and being distributed in a zigzag shape, a plurality of deep drainage holes being arranged in the top arch and on the upstream side of the drainage hole, a drainage channel being arranged at the entrance of the drainage hole, the drainage channel being connected with the highway side ditch.

[0008] While adopting the above technical scheme, the present application can also adopt or combine the following technical schemes:

[0009] As a preferred technical scheme of the present application, a geotextile is arranged in the deep intercepting drainage channel.

[0010] As a preferred technical scheme of the present application: the deep drainage groove is sequentially provided with geotextile, graded gravel, geotextile, stone residue and fully weathered soil from bottom to top.

[0011] As a preferred technical scheme of the present application: the geotextile is wrapped outside the geotextile.

[0012] As a preferred technical scheme of the present application: the bottom of the drainage blind ditch is sequentially provided with large stone, pebble, geotextile and sand gravel layer from bottom to top.

[0013] As a preferred technical scheme of the present application: a sand settling tank is arranged at the outlet of the drainage steel pipe.

[0014] As a preferred technical scheme of the present application: a horn mouth is arranged downstream of the sand settling tank and connected with the existing open channel or downstream river channel.

[0015] As a preferred technical scheme of the present application: the drainage hole has a cross section diameter of 3-5 m.

[0016] As a preferred technical scheme of the present application: the deep drainage hole is provided with a PE drainage flower pipe.

[0017] The second object of the present application is to provide a construction method of the slope type spoil ground drainage system.

[0018] To this end, the above object of the present application is achieved by the following technical scheme:

[0019] A construction method of the slope type spoil ground drainage system, the construction method is based on the drainage system as described above, and comprises the following steps:

[0020] S1: constructing a water intercepting ditch around the spoil ground boundary, and the water intercepting ditch adopts a reinforced concrete structure;

[0021] S2: removing the surface covering layer of the mountain, and changing the original gully and open channel into a drainage blind ditch, and layering and compacting from bottom to top in the order of large stone, pebble and sand gravel to the design elevation, and arranging a layer of geotextile between the pebble and sand gravel layers to prevent fine particles from blocking and ensure the drainage effect of the blind ditch;

[0022] S3: constructing a concrete spoil dam at the bottom slope toe of the spoil ground, embedding a drainage steel pipe in the dam body, arranging a reinforced concrete sand settling tank at the downstream outlet of the drainage steel pipe to settle fine particles in the seepage water of the spoil, arranging a horn mouth downstream of the sand settling tank to connect with the existing open channel or downstream river channel to discharge the seepage water of the spoil;

[0023] S4: the full weathered layer is excavated first at the position of the surface deep transverse and longitudinal staggered drainage groove of the mountain, a geotextile tube is arranged at the bottom and wrapped with geotextile, the inside of the drainage groove is backfilled with crushed stone and stone slag, the bottom of the drainage groove is wrapped with geotextile, the excavation platform at the top of the drainage groove is wrapped with geotextile and backfilled with stone slag, and then a layer of full weathered soil is backfilled on the upper part in a way of layering and rolling, and the slag is stacked in the slag yard, and the end of the drainage groove is effectively connected with the drainage steel pipe of the slag dam;

[0024] S5: after the slag is stacked in the slag yard to the designed elevation, a horse path is arranged on the surface, and a horse path drainage ditch is arranged on the inner side of the horse path to drain part of the natural slope precipitation;

[0025] S6: a zigzag drainage hole is excavated below the lower limit of the strong weathering at the bottom of the slag yard, the drainage hole is arranged along the slope to meet the drainage requirement of the drainage hole, the drainage hole is excavated by TBM to save the construction period, the excavation section diameter is preferably 3-5 m, a deep drainage hole is constructed in the drainage hole, a PE drainage flower pipe is buried in the deep drainage hole and wrapped with geotextile, a drainage ditch is excavated at the hole of the drainage hole and led to the existing highway side ditch to drain out.

[0026] The present application provides a slope type slag yard drainage system and a construction method, which has the following beneficial effects: the surface drainage system composed of the water interception ditch and the horse path drainage ditch, the shallow drainage system composed of the deep drainage groove and the drainage blind ditch, and the deep drainage system composed of the drainage hole and the deep drainage hole are combined, so that the underground water level and the surface seepage water can be efficiently and quickly reduced, and the stability of the slag yard is effectively ensured; the construction sequence is reasonably arranged, the slag stacking function of the slag yard is met as soon as possible, and the construction period is saved; meanwhile, the arrangement of the deep drainage system also provides safety protection for the whole slag yard drainage, and reduces the risk of overall instability and collapse of the slag body when the geotextile is aged or damaged. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 The present application provides a slope type slag yard drainage system and a construction method, which has the following beneficial effects: the surface drainage system composed of the water interception ditch and the horse path drainage ditch, the shallow drainage system composed of the deep drainage groove and the drainage blind ditch, and the deep drainage system composed of the drainage hole and the deep drainage hole are combined, so that the underground water level and the surface seepage water can be efficiently and quickly reduced, and the stability of the slag yard is effectively ensured; the construction sequence is reasonably arranged, the slag stacking function of the slag yard is met as soon as possible, and the construction period is saved; meanwhile, the arrangement of the deep drainage system also provides safety protection for the whole slag yard drainage, and reduces the risk of overall instability and collapse of the slag body when the geotextile is aged or damaged.

[0028] Figure 2 The present application provides a slope type slag yard drainage system and a construction method, which has the following beneficial effects: the surface drainage system composed of the water interception ditch and the horse path drainage ditch, the shallow drainage system composed of the deep drainage groove and the drainage blind ditch, and the deep drainage system composed of the drainage hole and the deep drainage hole are combined, so that the underground water level and the surface seepage water can be efficiently and quickly reduced, and the stability of the slag yard is effectively ensured; the construction sequence is reasonably arranged, the slag stacking function of the slag yard is met as soon as possible, and the construction period is saved; meanwhile, the arrangement of the deep drainage system also provides safety protection for the whole slag yard drainage, and reduces the risk of overall instability and collapse of the slag body when the geotextile is aged or damaged.

[0029] Figure 3 The present application provides a slope type slag yard drainage system and a construction method, which has the following beneficial effects: the surface drainage system composed of the water interception ditch and the horse path drainage ditch, the shallow drainage system composed of the deep drainage groove and the drainage blind ditch, and the deep drainage system composed of the drainage hole and the deep drainage hole are combined, so that the underground water level and the surface seepage water can be efficiently and quickly reduced, and the stability of the slag yard is effectively ensured; the construction sequence is reasonably arranged, the slag stacking function of the slag yard is met as soon as possible, and the construction period is saved; meanwhile, the arrangement of the deep drainage system also provides safety protection for the whole slag yard drainage, and reduces the risk of overall instability and collapse of the slag body when the geotextile is aged or damaged.

[0030] Figure 4 The present application provides a slope type slag yard drainage system and a construction method, which has the following beneficial effects: the surface drainage system composed of the water interception ditch and the horse path drainage ditch, the shallow drainage system composed of the deep drainage groove and the drainage blind ditch, and the deep drainage system composed of the drainage hole and the deep drainage hole are combined, so that the underground water level and the surface seepage water can be efficiently and quickly reduced, and the stability of the slag yard is effectively ensured; the construction sequence is reasonably arranged, the slag stacking function of the slag yard is met as soon as possible, and the construction period is saved; meanwhile, the arrangement of the deep drainage system also provides safety protection for the whole slag yard drainage, and reduces the risk of overall instability and collapse of the slag body when the geotextile is aged or damaged.

[0031] Figure 5 The present application provides a slope type slag yard drainage system and a construction method, which has the following beneficial effects: the surface drainage system composed of the water interception ditch and the horse path drainage ditch, the shallow drainage system composed of the deep drainage groove and the drainage blind ditch, and the deep drainage system composed of the drainage hole and the deep drainage hole are combined, so that the underground water level and the surface seepage water can be efficiently and quickly reduced, and the stability of the slag yard is effectively ensured; the construction sequence is reasonably arranged, the slag stacking function of the slag yard is met as soon as possible, and the construction period is saved; meanwhile, the arrangement of the deep drainage system also provides safety protection for the whole slag yard drainage, and reduces the risk of overall instability and collapse of the slag body when the geotextile is aged or damaged.

[0032] In the figure: 1 - water intercepting ditch; 2 - horse path drainage ditch; 3 - deep intercepting drainage groove; 4 - drainage blind ditch; 5 - drainage hole; 6 - drainage steel pipe; 7 - sand settling tank; 8 - horn mouth; 31 - geotextile; 32 - geotextile pipe; 33 - graded crushed stone; 34 - stone residue; 35 - fully weathered soil; 41 - large stone; 42 - pebble; 43 - geotextile; 44 - sand and gravel layer; 51 - drainage hole opening; 52 - deep drainage hole. DETAILED DESCRIPTION

[0033] The application will be further described in detail with reference to the accompanying drawings and specific examples.

[0034] As shown in the figure, a drainage system for a slope-type waste dump includes a surface drainage system, a shallow drainage system and a deep drainage system. Figures 1-5 The surface drainage system includes a water intercepting ditch 1 and a plurality of horse paths, the water intercepting ditch 1 is arranged around the edge of the waste dump, and the horse paths are arranged across the surface of the waste dump body, the inner side of the horse path is provided with a horse path drainage ditch 2 for draining surface seepage water, and the two ends of the horse path drainage ditch 2 are connected with the water intercepting ditch 1.

[0035] The shallow drainage system includes a plurality of deep intercepting drainage grooves 3 and drainage blind ditches 4, the deep intercepting drainage grooves 3 are arranged in a crisscross manner below the ground line of the waste dump and above the lower limit of the fully weathered zone, the deep intercepting drainage grooves 3 are connected with the drainage blind ditches 4, a waste retaining dam is built at the bottom slope of the waste dump for strengthening the anti-sliding stability of the waste body, a drainage steel pipe 6 is embedded downstream of the waste retaining dam, and the end of the deep intercepting drainage groove 3 is connected with the drainage steel pipe 6.

[0036] The deep drainage system includes a drainage hole 5, the drainage hole 5 is arranged below the lower limit of the strong weathered zone and is distributed in a zigzag shape as a whole, a plurality of deep drainage holes 52 are arranged at intervals on the inner top arch and the upstream side of the drainage hole 5, the interval between two adjacent deep drainage holes 52 is 6 m, and a drainage channel is arranged at the drainage hole opening 51 and is connected with a road side ditch.

[0037] The deep intercepting drainage groove 3 is provided with a geotextile 31.

[0038] The deep intercepting drainage groove is sequentially provided from bottom to top with a geotextile pipe 32, graded crushed stone 33, a geotextile pipe 32, stone residue 34 and fully weathered soil 35.

[0039] The geotextile pipe 32 is wrapped with a geotextile to filter fine particles on the surface of the waste body and prevent the geotextile pipe from being blocked.

[0040] The drainage blind ditch 4 is built from the original drainage gully and open channel position, and the bottom of the drainage blind ditch 4 is sequentially provided from bottom to top with large stones 41, pebbles 42, a geotextile 43 and a sand and gravel layer 44.

[0041] A sand settling tank 7 is arranged at the outlet of the drainage steel pipe 6 to precipitate fine particles in the seepage water of the waste body.

[0042] A trumpet mouth 8 is arranged downstream of the sand trap 7 and is connected with the existing open channel or downstream river to discharge the seepage water of the residue.

[0043] The cross-sectional diameter of the drainage hole 5 is 3-5 m.

[0044] The PE drainage flower pipe is arranged in the deep drainage hole 52 and is wrapped with geotextile to filter the fine particles on the surface of the residue.

[0045] To achieve rapid drainage and meet the functional requirements of the residue disposal site, the deep drainage groove 3 and the blind drainage ditch 4 are first constructed on the surface of the residue disposal site after removing the covering layer, and then the residue disposal site is stacked after the construction is completed. Meanwhile, the drainage hole 5 and the deep drainage hole 52 are excavated and constructed, and the horse path and the horse path drainage ditch 2 are arranged on the slope surface after the residue is stacked to the designed elevation.

[0046] The arrangement of the deep drainage system also provides safety guarantee for the overall drainage of the residue disposal site. It is mainly considered that if the geotextile in the horizontal and vertical staggered drainage groove 3 in the shallow drainage system is aged or damaged during use, the fine particles in the residue will be taken away during the drainage in the drainage groove 3, which will easily lead to the instability of the residue and the collapse.

[0047] Specifically, the above-mentioned drainage system of the slope residue disposal site is implemented by the following steps:

[0048] S1: A drainage ditch is constructed around the edge line of the residue disposal site, and the drainage ditch is made of reinforced concrete structure;

[0049] S2: After removing the covering layer on the surface of the mountain, the original gully and open channel on the surface are changed into blind drainage ditches, and the large stones, pebbles and gravel are layered and compacted from bottom to top to the designed elevation. In order to ensure the drainage effect of the blind drainage ditch and prevent the fine particles from being blocked, a layer of geotextile is arranged between the pebble and gravel layers;

[0050] S3: A concrete residue retaining dam is built at the bottom of the residue disposal site, a drainage steel pipe is embedded in the dam body, a reinforced concrete sand trap is arranged at the downstream outlet of the drainage steel pipe to deposit the fine particles in the seepage water of the residue, and a trumpet mouth is arranged downstream of the sand trap to connect with the existing open channel or downstream river to discharge the seepage water of the residue;

[0051] S4: The full weathering layer is removed at the position of the deep horizontal and vertical staggered drainage groove on the surface of the mountain, the geotextile pipe is arranged at the bottom and wrapped with geotextile, the stone and residue are backfilled in the drainage groove, the geotextile is wrapped at the bottom of the drainage groove, the geotextile pipe is wrapped with geotextile and the stone is backfilled on the excavation platform at the top of the drainage groove, and then the residue is stacked on the full weathering soil in the layered and compacted manner, and the drainage groove is effectively connected with the drainage steel pipe of the residue retaining dam at the end.

[0052] S5: After the slag is stacked to the design elevation, a horse path is set on the surface, and a horse path drainage ditch is set inside the horse path to drain part of the natural slope precipitation;

[0053] S6: Zigzag drainage holes are excavated below the lower limit of strong weathering at the bottom of the slag yard. To meet the drainage requirements of the drainage holes, the drainage holes are arranged along the slope. To save construction period, the drainage holes can be excavated by TBM method. The excavation section diameter is preferably 3-5 m. Deep drainage holes are constructed in the drainage holes. PE drainage flower pipes are buried in the deep drainage holes and are treated with geotextile. A drainage ditch is excavated at the hole opening of the drainage hole and is led to the existing highway side ditch for drainage.

[0054] The above specific embodiments are used to explain and illustrate the present application, and are only preferred embodiments of the present application, rather than limiting the present application. Any modification, equivalent replacement, improvement, etc. made to the present application within the spirit of the present application and the protection scope of the claims falls within the protection scope of the present application.

Claims

1. A drainage system for a slope-type spoil heap, characterized in that: It includes a surface drainage system, a shallow drainage system and a deep drainage system. The surface drainage system includes a water interception ditch (1) and several horse walkways. The water interception ditch (1) is set around the edge of the slag yard. The horse walkways are set across the surface of the slag pile. The horse walkway drainage ditch (2) is provided on the inner side of the horse walkway. The two ends of the horse walkway drainage ditch (2) are connected to the water interception ditch (1). The shallow drainage system includes several deep intercepting drainage channels (3) and drainage blind ditches (4). The deep intercepting drainage channels (3) are arranged in a crisscross pattern below the ground line of the spoil disposal site and above the lower limit of the fully weathered zone. The deep intercepting drainage channels (3) are connected to the drainage blind ditches (4), and the end of the deep intercepting drainage channels (3) is connected to the drainage steel pipe (6). The deep drainage system includes a drainage tunnel (5), which is located below the lower limit of the strong weathering zone and is distributed in a zigzag shape. The drainage tunnel (5) has several deep drainage holes (52) spaced at intervals on the inner arch and the upstream side. The opening (51) of the drainage tunnel is provided with a drainage channel, which is connected to the roadside ditch.

2. The drainage system for a slope-type spoil heap according to claim 1, characterized in that: Geotextile (31) is installed inside the deep drainage ditch (3).

3. The drainage system for a slope-type spoil heap according to claim 1, characterized in that: The deep drainage trench is arranged from bottom to top as follows: geotextile pipe (32), graded crushed stone (33), geotextile pipe (32), stone chips (34), and completely weathered soil (35).

4. The drainage system for a slope-type spoil heap according to claim 3, characterized in that: The geotextile pipe (32) is wrapped with geotextile.

5. The drainage system for a slope-type spoil heap according to claim 1, characterized in that: The bottom of the drainage blind ditch (4) is arranged from bottom to top as large stones (41), pebbles (42), geotextile (43), and gravel layer (44).

6. The drainage system for a slope-type spoil heap according to claim 1, characterized in that: A sedimentation tank (7) is installed at the outlet of the drainage steel pipe (6).

7. The drainage system for a slope-type spoil heap according to claim 6, characterized in that: The sedimentation basin (7) is provided with a funnel-shaped opening (8) downstream, which is connected to the existing open channel or downstream river channel.

8. The drainage system for a slope-type spoil heap according to claim 1, characterized in that: The diameter of the drainage hole (5) is 3-5 m.

9. The drainage system for a slope-type spoil heap according to claim 1, characterized in that: The deep drainage hole (52) is equipped with a PE drainage pipe.

10. A construction method for a drainage system for a slope-type spoil heap, characterized in that: The construction method is based on the system described in any one of claims 1-9 and includes the following steps: S1: Construct intercepting ditches around the perimeter of the slag dump. The intercepting ditches shall be constructed of reinforced concrete. S2: After removing the surface cover layer of the mountain, the original gullies and open channels on the surface are converted into drainage blind ditches. The ditches are laid and compacted in layers from bottom to top in the order of large stones, pebbles and gravel to the design elevation. To ensure the drainage effect of the blind ditches and prevent fine particles from clogging them, a layer of geotextile is placed between the pebble and gravel layers. S3: Concrete retaining dam is built at the bottom slope of the spoil disposal site. A drainage steel pipe is pre-embedded in the dam body. A reinforced concrete sedimentation tank is set at the downstream outlet of the drainage steel pipe to settle fine particles in the seepage water of the spoil. A funnel-shaped opening is set at the downstream of the sedimentation tank to connect with the existing open channel or downstream river to discharge the seepage water of the spoil. S4: First, remove the completely weathered layer from the deep, crisscrossing interception and drainage trenches on the mountain surface. Then, lay geotextile pipes at the bottom and wrap them with geotextile fabric. Backfill the inside of the interception and drainage trenches with crushed stone and stone chips, and wrap the bottom of the interception and drainage trenches with geotextile fabric. After the excavation platform at the top of the drainage trenches is treated with geotextile pipes wrapped with geotextile fabric and stone chips backfilled, backfill a layer of completely weathered soil on top and pile the waste in the spoil disposal site by layered compaction. The end of the drainage trench is effectively connected to the drainage steel pipe of the slag retaining dam. S5: After the spoil heap is piled up to the design elevation, a horse walkway is set up on the surface, and a horse walkway drainage ditch is set up on the inside of the horse walkway to drain some of the natural slope rainwater. S6: A zigzag drainage tunnel will be excavated below the strong weathering limit at the bottom of the slag heap. To meet the drainage needs of the drainage tunnel, it will be arranged along the slope. To save construction time, the drainage tunnel will be excavated using the TBM method. The diameter of the excavation section should be 3-5 m. Deep drainage holes will be constructed inside the drainage tunnel. PE drainage pipes will be buried in the deep drainage holes and wrapped with geotextile. A drainage ditch will be excavated at the entrance of the drainage tunnel to lead to the existing roadside ditch for discharge.

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