A construction method for embankment structure for landslide foundation treatment

Abstract

This invention relates to embankment structures for landslide foundation treatment, comprising bedrock, a weak sliding layer, a base course, embankment fill, anti-slide piles, counterweight retaining walls, vertical drainage pipes, and horizontal drainage pipes. The weak sliding layer is located above the bedrock, and the base course is located above the weak sliding layer. A water-cutting curtain is installed at the top of the landslide, and a water-cutting ditch is installed at the top of the water-cutting curtain. Vertical and horizontal drainage pipes are installed in the landslide foundation, arranged in rows. The vertical drainage pipes are vertical, with their bottom ends embedded in the bedrock to a certain depth, and their top outlets extending out of the base course and embedded in the gravel layer. The horizontal drainage pipes are horizontal or have their outlets tilted downwards at a certain angle, and are not embedded in the bedrock. The beneficial effects of this invention are: by employing a comprehensive treatment method combining water interception, weak layer drainage, anti-slide measures, load reduction, and counterweight to construct an embankment structure for landslide foundations, this invention significantly improves the anti-slide capacity of the landslide foundation embankment.

Description

Technical Field

[0001] The invention relates to an embankment structure, in particular to an embankment structure for landslide foundation treatment and a construction method, belonging to the field of roadbed engineering. Background Art

[0002] When building an embankment on a hillside foundation with a weak sliding layer, the loading of the embankment often causes landslides in the originally unstable strata. The main reason for the landslide is that the embankment loading causes the sliding force of the landslide to exceed the anti-sliding force. In addition, since the sliding layer itself has weak soil and high water content, the construction of the embankment will cause embankment seepage and slope water to enter the sliding layer. When there is abundant precipitation, the sliding layer is not drained well, causing the weak soil in the sliding layer to lose strength and the landslide to lose anti-sliding force. Existing landslide treatment structures often use huge anti-sliding piles to block landslides. Traditional drainage holes can only passively seep water and cannot actively drain water. There is no way to reduce the embankment load. The above difficulties limit the construction of embankment structures in landslide strata, and new treatment structures and construction methods are urgently needed. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and to provide a landslide foundation treatment embankment structure and a construction method.

[0004] The landslide foundation treatment embankment structure includes bedrock, a weak sliding layer, a base layer, embankment fill, anti-sliding piles, counter-pressure berms, vertical drainage pipes and transverse drainage pipes; the bedrock is above the weak sliding layer, and the soft sliding layer is above the base layer; a water-cutting curtain is arranged at the top of the landslide, and a water-cutting ditch is arranged on the top of the water-cutting curtain; vertical drainage pipes and transverse drainage pipes are arranged in the landslide foundation, and the vertical drainage pipes and transverse drainage pipes are arranged in rows; the vertical drainage pipe is vertically oriented, the bottom end of the vertical drainage pipe is embedded in the bedrock to a certain depth, and the outlet at the top of the vertical drainage pipe extends out of the base layer and is embedded in the gravel layer; the transverse drainage pipe is horizontally oriented or the outlet is tilted downward at a certain angle, the transverse drainage pipe is not embedded in the bedrock, and one end of the transverse drainage pipe is embedded in the bedrock The horizontal drainage pipe is inserted into the weak sliding layer, and the outlet at the other end of the horizontal drainage pipe extends out of the foundation layer and is embedded in the gravel layer; the vertical drainage pipe is filled with gravel; a gravel layer is filled above the foundation layer, and a cable is connected to the top of the vertical drainage pipe, and the cable is led out of the ground from the gravel layer; the outlet of the horizontal drainage pipe is also connected to the cable; embankment fill is filled above the gravel layer, and a graded protection wall is arranged above the embankment fill. The graded protection wall is formed by connecting multiple levels of prefabricated reinforced concrete retaining walls to each other, and foam concrete is poured on the inside of the graded protection wall, and a road surface is arranged on the top of the foam concrete, and the elevation of the road surface is lower than the elevation of the graded protection wall by a certain distance; anti-slip piles are arranged at the foot of the embankment slope, and the top of the anti-slip piles are embedded in the counter-pressure berm above them.

[0005] Preferably: the vertical drainage pipe adopts a metal pipe with a diameter of 300-800mm, and the transverse drainage pipe adopts a metal pipe with a diameter of 100-300mm; the vertical drainage pipe and the transverse drainage pipe are provided with drainage holes on the section pipe body of the weak sliding layer, and filter cloth is installed in the pipe; the filter cloth of the transverse drainage pipe is wrapped with coarse sand; the filter cloth of the vertical drainage pipe is wrapped with gravel, and a grouting pipe is arranged in the gravel; the grouting pipe adopts a metal pipe with a diameter of 20-30mm, and the metal pipe is provided with grouting holes on the section pipe body in the vertical drainage pipe.

[0006] Preferably, the water-cutting curtain is a self-setting mortar wall, which is arranged along the upper slope foot of the embankment fill.

[0007] Preferably, anti-seepage geotextile is laid around the embankment fill.

[0008] Preferably, the multi-level prefabricated reinforced concrete retaining wall adopted by the graded protective wall is a cantilever retaining wall, the top of the prefabricated reinforced concrete retaining wall is provided with embedded screws, the bottom plate of the prefabricated reinforced concrete retaining wall is provided with connecting holes, the embedded screws on the top of the next level prefabricated reinforced concrete retaining wall are inserted into the connecting holes of the bottom plate of the previous level prefabricated reinforced concrete retaining wall and are fixed by anchor heads.

[0009] Preferably, the anti-slide piles are bored cast-in-place piles with a square or circular cross-section.

[0010] Preferably, a drainage ditch is provided at the bottom of the gravel layer.

[0011] Preferably, the top end of the vertical drainage pipe is connected to a horizontal drainage branch pipe, the drainage branch pipe is connected to a longitudinal drainage main pipe, and the drainage main pipe is connected to a vacuum pump.

[0012] The construction method of the landslide foundation treatment embankment structure comprises the following steps:

[0013] 1) Use metal pipes to make vertical drainage pipes, horizontal drainage pipes and grouting pipes. Drainage holes are drilled on the pipe bodies of the vertical drainage pipes and horizontal drainage pipes at the designed positions, and grouting holes are drilled on the pipe bodies of the grouting pipes at the designed positions;

[0014] 2) Use filter cloth to make a bag body, the diameter of the bag body is the same as the inner diameter of the vertical drainage pipe and the horizontal drainage pipe, install the bag body into the vertical drainage pipe and the horizontal drainage pipe, set the grouting pipe at the center of the bag body of the vertical drainage pipe, and fill the bag body of the horizontal drainage pipe with coarse sand;

[0015] 3) Dig steps on the surface of the landslide foundation and lay anti-seepage geotextile;

[0016] 4) A self-setting mortar groove is excavated at the foot of the upper slope of the designed embankment fill. The bottom of the groove penetrates the weak sliding layer and embeds into the bedrock to a certain depth, and self-setting mortar is poured into the groove;

[0017] 5) Construct bored cast-in-place piles as anti-slide piles at the design location of the anti-slide piles;

[0018] 6) Use a vertical drilling rig to drill a hole and use a crane to lift a vertical drainage pipe, fill the vertical drainage pipe with gravel, and connect a cable to the top of the vertical drainage pipe;

[0019] 7) Use a horizontal drilling rig to drill holes and manually insert a horizontal drainage pipe, and connect a cable to the outlet of the horizontal drainage pipe;

[0020] 8) Connect the top of each row of vertical drainage pipes to a horizontal drainage branch pipe, and each drainage branch pipe is connected to a drainage main pipe arranged along the longitudinal direction of the embankment. The drainage branch pipes are arranged in a stepped manner along the transverse direction of the embankment according to the elevation of the top of the vertical drainage pipes. The drainage main pipe is arranged outside the embankment. The drainage main pipe is connected to a vacuum pump to pump water;

[0021] 9) Connect the cables at the top of each row of vertical drainage pipes to the conductors, so that the cables at the top of two adjacent rows of vertical drainage pipes are connected to different conductors, and the conductors of two adjacent rows of vertical drainage pipes are respectively connected to the anode and cathode of the DC power supply, turn on the DC power supply for electroosmosis, and control the voltage within 36V;

[0022] 10) Connect the cables of each row of transverse drainage pipes to the conductors, so that the cables of two adjacent rows of transverse drainage pipes are connected to different conductors, and the conductors of two adjacent rows of transverse drainage pipes are respectively connected to the anode and cathode of the DC power supply, turn on the DC power supply for electroosmosis, and control the voltage within 36V;

[0023] 11) After the water output of electroosmosis drainage is significantly reduced, remove the cables and DC power supply of the horizontal drainage pipe, keep the DC power supply and vacuum pump of the vertical drainage pipe to continue working, fill the gravel layer and compact it;

[0024] 12) Fill the embankment in layers. After filling to a certain height, remove the cables, DC power supply and vacuum pump connected to the vertical drainage pipe, connect the grouting pipe of the vertical drainage pipe to the grouting pump and inject cement slurry into the vertical drainage pipe;

[0025] 13) Remove the grouting pipe and grouting pump, and continue to fill the embankment to the designed elevation. Set steps on the top of the embankment and lay anti-seepage geotextiles. Also lay anti-seepage geotextiles on the slopes on both sides of the embankment.

[0026] 14) Casting of plain concrete anti-pressure berm at the foot of the lower slope of the embankment fill;

[0027] 15) Hoist the first-level prefabricated reinforced concrete retaining wall, pour foam concrete on the inner side of the first-level reinforced concrete retaining wall, and set settlement joints during pouring;

[0028] 16) Hoist the second-level prefabricated reinforced concrete retaining wall, insert the embedded screws on the top of the first-level reinforced concrete retaining wall into the connection holes of the bottom plate of the second-level prefabricated reinforced concrete retaining wall, fix it with anchor heads, and pour foam concrete on the inside of the second-level prefabricated reinforced concrete retaining wall;

[0029] 17) Hoist the third-level prefabricated reinforced concrete retaining wall and pour foam concrete as needed;

[0030] 18) The pavement is constructed on top of the foam concrete, with the pavement elevation being a certain distance lower than the elevation of the precast reinforced concrete retaining wall.

[0031] The beneficial effects of the present invention are:

[0032] 1. The present invention adopts water interception, weak layer drainage, anti-slip, load reduction and counter-pressure comprehensive treatment of landslide foundation to build embankment structure, so that the anti-slip ability of landslide foundation embankment is greatly improved.

[0033] 2. The self-setting mortar wall is embedded in the bedrock, and the embankment fill is wrapped with anti-seepage geotextile, which can prevent groundwater and precipitation outside the roadbed from entering the roadbed, solving the problem of loss of strength of the weak sliding layer caused by precipitation infiltration.

[0034] 3. The present invention reduces the moisture content of the soil in the weak sliding layer by arranging vertical drainage pipes and horizontal drainage pipes for electroosmosis drainage, which can improve the shear strength of the weak sliding layer and improve the anti-slip ability. The vertical drainage pipe can drain water during the construction period, and can play an anti-slip role by forming steel pipe gravel concrete piles after grouting during the operation period. The horizontal drainage pipe is arranged horizontally or downwardly, and can drain water by gravity during the construction and operation periods. The drainage in the vertical drainage pipe and the horizontal drainage pipe enters the gravel layer, flows out from the gravel layer, and is collected and discharged in the drainage ditch. The gravel layer can play a comprehensive role of drainage, cushioning, and shear resistance.

[0035] 4. Foam concrete embankment is used above the embankment fill. Foam concrete has the characteristics of low weight and self-support, which can greatly reduce the design section of the embankment, reduce the amount of fill and fill load as well as the land area. At the same time, foam concrete can reduce the weight of the embankment itself, achieve the load-reducing effect of the high embankment, and thus reduce the sliding force of the landslide.

[0036] 5. The foam concrete embankment is cast with graded protective walls as the template. The graded protective walls can ensure the stability of the foam concrete embankment. At the same time, the top of the wall is higher than the road surface and can be used as a guardrail.

[0037] 6. Anti-slip piles are set at the foot of the slope to play an anti-slip role. At the same time, concrete counter-pressure berms are set at the bottom of the embankment to further improve the anti-slip stability of the embankment. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1The cross-sectional layout of the embankment structure for landslide foundation treatment;

[0039] Figure 2 It is the layout diagram of the drainage pipe and electro-osmosis system;

[0040] Figure 3 It is a schematic diagram of the structure of the graded protection wall;

[0041] Figure 4 It is a schematic diagram of the vertical drainage pipe structure;

[0042] Figure 5 Schematic diagram of the horizontal drainage pipe structure.

[0043] Explanation of the reference numerals: bedrock 1, water-cutting curtain 2, weak sliding layer 3, foundation layer 4, water-cutting ditch 5, embankment fill 6, road surface 8, graded protective wall 9, foam concrete 10, anti-slide piles 11, counter-pressure berm 12, drainage ditch 13, anti-seepage geotextile 14, gravel layer 15, grouting pipe 16, vertical drainage pipe 17, horizontal drainage pipe 18, conductor 19, DC power supply 20, vacuum pump 21, embedded screw 22, anchor head 23, prefabricated reinforced concrete retaining wall 24, cable 25, filter cloth 26, gravel 27, coarse sand 28. DETAILED DESCRIPTION

[0044] The present invention is further described below in conjunction with embodiments. The description of the following embodiments is only used to help understand the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principles of the present invention, several improvements and modifications may be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0045] The landslide foundation treatment embankment structure includes bedrock 1, a water cut-off curtain 2, a weak sliding layer 3, a base layer 4, embankment fill 6, a foam concrete embankment, anti-slide piles 11, a back-pressure berm 12, a horizontal drainage pipe 18, and a vertical drainage pipe 7.

[0046] A water cut-off curtain 2 is provided at the top of the landslide, and a water cut-off ditch 5 is provided at the top of the water cut-off curtain 2. The water cut-off curtain 2 is a self-setting mortar wall, which is provided along the foot of the embankment fill slope. The bottom of the water cut-off curtain 2 is embedded in the bedrock 1. The thickness of the water cut-off curtain 2 is 600-800 mm. The self-setting mortar wall is embedded in the bedrock 1, and the embankment fill 6 is wrapped with an anti-seepage geotextile 14, which can prevent groundwater and precipitation outside the roadbed from entering the roadbed, and solve the problem of loss of strength of the weak sliding layer caused by precipitation infiltration.

[0047] A vertical drainage pipe 17 and a horizontal drainage pipe 18 are arranged in a row in the landslide foundation. The vertical drainage pipe 17 is vertical, and the bottom end is embedded in the bedrock 1 to a certain depth. The horizontal drainage pipe 18 is horizontal or the outlet is tilted downward at a certain angle, and the bottom end is not embedded in the bedrock 1. The top of the vertical drainage pipe 17 and the outlet of the horizontal drainage pipe 18 extend out of the foundation 4 and are embedded in the gravel layer 15. The vertical drainage pipe 17 is filled with gravel 27. One end of the horizontal drainage pipe 18 is embedded in the weak sliding layer 3, and the other end extends out of the foundation 4. The gravel layer 15 is filled above the foundation 4. The top of the vertical drainage pipe 17 is connected to a cable 25, and the cable 25 is led out of the gravel layer 15 to the ground. The end of the horizontal drainage pipe 18 outside the roadbed is also connected to a cable 25. The vertical drainage pipe 17 is a metal pipe with a diameter of 300-800mm, and the horizontal drainage pipe 18 is a metal pipe with a diameter of 100-300mm. The metal pipe is full of drainage holes on the section pipe body of the weak sliding layer 3, and a filter cloth 26 is installed in the pipe; the filter cloth 26 of the horizontal drainage pipe 18 is wrapped with coarse sand 28; the filter cloth 26 of the vertical drainage pipe 17 is wrapped with crushed stone 27, and a grouting pipe 16 is arranged in the crushed stone 27; the grouting pipe 16 is a metal pipe with a diameter of 20-30mm, and the metal pipe is full of grouting holes on the section pipe body in the vertical drainage pipe 17. The vertical drainage pipe 17 is made of a thick steel pipe, which is conductive, and the crushed stone inside it can be used as a drainage body. The top of the vertical drainage pipe 17 is connected to a horizontal drainage branch pipe, and the drainage branch pipe is connected to the longitudinal drainage main pipe, and the drainage main pipe is connected to a vacuum pump 21, and the water is discharged through the vacuum pump 21. Each row of vertical drain pipes 17 is connected to a drainage branch pipe through a tee, a hole is drilled on the tee, and the grouting pipe 16 in the vertical drain pipe 17 passes through the drilled hole on the tee, and then the water-expanding rubber and tape are wrapped to seal the drilled hole. Coarse sand is used as the drainage body in the horizontal drain pipe 18, which is horizontally arranged or tilted downward, so there is no need to use a vacuum pump 21 to pump water, and gravity drainage can be achieved. Each row of vertical drain pipes 17 is connected together with the same wire 19 as an anode or cathode, and an adjacent row of vertical drain pipes is used as a cathode or anode. Each row of horizontal drain pipes 18 is connected together with the same wire as an anode or cathode, and an adjacent row of horizontal drain pipes 18 is used as a cathode or anode. Under the action of electroosmosis, the moisture in the weak sliding layer 3 flows from the anode drain pipe into the cathode drain pipe, and then is discharged by the vacuum pump 21. In addition to drainage by electroosmosis, fill load will also cause the moisture in the weak sliding layer to be discharged. After the drainage volume is significantly reduced, the vertical drainage pipe can be grouted to form a crushed stone grouting steel pipe pile, which plays the role of an anti-slip pile. The transverse drainage pipe is not grouted, and drainage can continue during the highway operation stage. The outlets of the vertical drainage pipe 17 and the transverse drainage pipe 18 are both in the crushed stone layer 15, and drainage can be carried out through the crushed stone layer. In addition, the crushed stone layer can also play the role of a cushion layer and an anti-slip effect.By setting up vertical and horizontal drainage pipes for electroosmosis drainage to reduce the moisture content of the soil in the weak sliding layer, the shear strength of the weak sliding layer can be improved and the anti-sliding ability can be improved.

[0048] The embankment fill 6 is filled above the gravel layer 15, and a graded protection wall 9 is arranged above the embankment fill 6. The graded protection wall 9 is formed by connecting multiple prefabricated reinforced concrete retaining walls. Foamed concrete 10 is poured inside the graded protection wall 9, and a road surface 8 is arranged on the top of the foamed concrete 10. The elevation of the road surface is lower than the elevation of the graded protection wall by a certain distance. Anti-sliding piles 11 are arranged at the foot of the embankment slope, and the top of the anti-sliding piles 11 is embedded in the anti-pressure berm 12 above it. The multi-stage prefabricated reinforced concrete retaining wall used in the graded protection wall 9 is a cantilever retaining wall. The top of the prefabricated reinforced concrete retaining wall 24 is provided with embedded screws 22, and the bottom plate is reserved with connection holes. The embedded screws on the top of the next level of prefabricated reinforced concrete retaining wall are inserted into the connection holes of the bottom plate of the previous level of prefabricated reinforced concrete retaining wall and fixed by anchor heads 23. The anti-sliding piles 11 are bored piles with square or circular cross-sections. The foam concrete embankment is used above the embankment fill 6. The foam concrete has the characteristics of low weight and self-sustaining, which can greatly reduce the design section of the embankment, reduce the amount of fill, fill load and land area, and at the same time, the foam concrete can reduce the weight of the embankment itself, achieve the load reduction effect of the high embankment, and thus reduce the sliding force of the landslide. The foam concrete embankment is cast with a graded protection wall as a template. The graded protection wall can ensure the stability of the foam concrete embankment, and the top of the wall is higher than the road surface and can be used as a guardrail. Anti-slip piles are set at the foot of the slope to play an anti-slip role, and a concrete counter-pressure berm is set at the lower part of the embankment to further improve the anti-slip stability of the embankment.

[0049] The construction method of the landslide foundation treatment embankment structure comprises the following steps:

[0050] 1) Use metal pipes to make vertical drainage pipes 17, horizontal drainage pipes 18 and grouting pipes 16. Drainage holes are drilled at the designed positions on the pipe bodies of the vertical drainage pipes 17 and the horizontal drainage pipes 18, and grouting holes are drilled at the designed positions on the pipe body of the grouting pipe 16;

[0051] 2) A bag body is made of filter cloth 26, the diameter of the bag body is the same as the inner diameter of the vertical drainage pipe 17 and the horizontal drainage pipe 18, the bag body is installed into the vertical drainage pipe 17 and the horizontal drainage pipe 18, the grouting pipe 16 is set at the center of the bag body of the vertical drainage pipe 17, and the coarse sand 28 is filled in the bag body of the horizontal drainage pipe 18;

[0052] 3) Dig steps on the surface of the landslide foundation and lay anti-seepage geotextile;

[0053] 4) A self-setting mortar groove is excavated at the foot of the upper slope of the designed embankment fill. The bottom of the groove penetrates the weak sliding layer 3 and is embedded in the bedrock 1 to a certain depth, and self-setting mortar is poured into the groove;

[0054] 5) Construct bored cast-in-place piles as anti-slide piles at the anti-slide pile design location 11;

[0055] 6) Drill a hole using a vertical drilling rig and hoist a vertical drainage pipe 17 into the hole using a crane, fill the vertical drainage pipe 17 with gravel 27, and connect a cable 25 to the top of the vertical drainage pipe 17;

[0056] 7) Drilling a hole with a horizontal drilling rig and manually inserting a transverse drainage pipe 18, and connecting a section of cable 25 to the outlet of the transverse drainage pipe 18;

[0057] 8) Connect the top of each row of vertical drainage pipes 17 to a horizontal drainage branch pipe, and each drainage branch pipe is connected to a drainage main pipe arranged along the longitudinal direction of the embankment. The drainage branch pipes are arranged in a stepped manner along the transverse direction of the embankment according to the elevation of the top of the vertical drainage pipes. The drainage main pipe is arranged outside the embankment. The drainage main pipe is connected to a vacuum pump 21 to pump water;

[0058] 9) Connect the cable 25 at the top of each row of vertical drainage pipes 17 to the wire 19, so that the cables 25 at the top of two adjacent rows of vertical drainage pipes 17 are connected to different wires 19, and the wires 19 of two adjacent rows of vertical drainage pipes 17 are respectively connected to the anode and cathode of the DC power supply 20, and the DC power supply 20 is turned on for electroosmosis, and the voltage is controlled within 36V;

[0059] 10) Operate each row of transverse drainage pipes 18 in the same manner as in step 7;

[0060] 11) After the water output of electroosmosis drainage is significantly reduced, the cable 25 and the DC power supply 20 of the horizontal drainage pipe 18 are removed, the DC power supply 20 and the vacuum pump 21 of the vertical drainage pipe 17 are retained to continue working, and the gravel layer 15 is filled and compacted;

[0061] 12) Fill the embankment soil 6 in layers. After filling to a certain height, remove the cable 25, DC power supply 20 and vacuum pump 21 connected to the vertical drainage pipe 17, connect the grouting pipe 16 of the vertical drainage pipe 17 to the grouting pump, and inject cement slurry into the vertical drainage pipe 17;

[0062] 13) Remove the grouting pipe 16 and the grouting pump, and continue to fill the embankment fill 6 to the designed elevation. Set a step on the top of the embankment fill 6 and lay an anti-seepage geotextile 14. Also lay an anti-seepage geotextile 14 on the slopes on both sides of the embankment fill 6.

[0063] 14) Casting a plain concrete anti-pressure berm 12 at the foot of the lower slope of the embankment fill 6;

[0064] 15) hoisting the first-level prefabricated reinforced concrete retaining wall 24, pouring the foamed concrete 10 inside the first-level prefabricated reinforced concrete retaining wall 24, and setting a settlement joint in the longitudinal direction during pouring;

[0065] 16) The second-level prefabricated reinforced concrete retaining wall 24 is hoisted, the embedded screws 22 on the top of the first-level prefabricated reinforced concrete retaining wall 24 are inserted into the connection holes of the bottom plate of the second-level prefabricated reinforced concrete retaining wall 24, and are fixed with anchor heads 23, and foam concrete 10 is poured inside the second-level prefabricated reinforced concrete retaining wall 24;

[0066] 17) Hoist the third-level prefabricated reinforced concrete retaining wall 24 and pour the foam concrete 10 as needed;

[0067] 18) A road surface 8 is constructed on top of the foam concrete 10 , and the elevation of the road surface 8 is lower than the elevation of the prefabricated reinforced concrete retaining wall 24 by a certain distance.

Claims

1. A construction method for a landslide foundation treatment embankment structure, characterized in that: The invention comprises a bedrock (1), a weak sliding layer (3), a foundation layer (4), embankment fill (6), anti-sliding piles (11), a back pressure berm (12), a vertical drainage pipe (17) and a horizontal drainage pipe (18); the weak sliding layer (3) is located above the bedrock (1), and the foundation layer (4) is located above the weak sliding layer (3); a water cut-off curtain (2) is arranged at the top of the landslide, and a water cut-off ditch (5) is arranged at the top of the water cut-off curtain (2); a vertical drainage pipe (17) and a horizontal drainage pipe (18) are arranged in the landslide foundation. The axial drainage pipe (18), the vertical drainage pipe (17) and the transverse drainage pipe (18) are arranged in a row; the vertical drainage pipe (17) is vertically oriented, the bottom end of the vertical drainage pipe (17) is embedded in the bedrock (1) to a certain depth, the outlet of the top end of the vertical drainage pipe (17) extends out of the foundation layer (4) and is embedded in the gravel layer (15); the transverse drainage pipe (18) is horizontally oriented or the outlet is inclined downward at a certain angle, one end of the transverse drainage pipe (18) is embedded in the weak sliding layer (3), and the transverse drainage pipe (18) is vertically oriented, the bottom end of the vertical drainage pipe (17) is embedded in the bedrock (1) to a certain depth, the outlet of the top end of the vertical drainage pipe (17) extends out of the foundation layer (4) and is embedded in the gravel layer (15); The outlet of the other end of the water pipe (18) extends out of the base layer (4) and is embedded in the gravel layer (15); the vertical drainage pipe (17) is filled with gravel (27); the gravel layer (15) is filled above the base layer (4); the top of the vertical drainage pipe (17) is connected to a cable (25), and the cable (25) is led out of the ground from the gravel layer (15); the outlet of the horizontal drainage pipe (18) is also connected to the cable (25); the gravel layer (15) is filled with embankment fill (6) A graded protection wall (9) is arranged above the embankment fill (6), the graded protection wall (9) is formed by connecting multiple levels of prefabricated reinforced concrete retaining walls, foam concrete (10) is poured inside the graded protection wall (9), a road surface (8) is arranged on the top of the foam concrete (10), and the elevation of the road surface (8) is lower than the elevation of the graded protection wall (9) by a certain distance; anti-sliding piles (11) are arranged at the foot of the embankment slope, and the top of the anti-sliding piles (11) is embedded in the anti-pressure berm (12) above it; The vertical drainage pipe (17) is a metal pipe with a diameter of 300-800 mm, and the horizontal drainage pipe (18) is a metal pipe with a diameter of 100-300 mm; the vertical drainage pipe (17) and the horizontal drainage pipe (18) are provided with drainage holes on the pipe body of the weak sliding layer (3), and filter cloth (26) is installed in the pipe; the filter cloth (26) of the horizontal drainage pipe (18) is wrapped with coarse sand (28); the filter cloth (26) of the vertical drainage pipe (17) is wrapped with crushed stone (27), and a grouting pipe (16) is arranged in the crushed stone (27); the grouting pipe (16) is a metal pipe with a diameter of 20-30 mm, and the metal pipe is provided with grouting holes on the pipe body of the vertical drainage pipe (17); The following steps are involved: 1) using metal pipes to make vertical drainage pipes (17), horizontal drainage pipes (18) and grouting pipes (16), drilling drainage holes at designed positions on the pipe bodies of the vertical drainage pipes (17) and the horizontal drainage pipes (18), and drilling grouting holes at designed positions on the pipe body of the grouting pipe (16); 2) using filter cloth (26) to make a bag body, the diameter of the bag body being the same as the inner diameter of the vertical drainage pipe (17) and the horizontal drainage pipe (18), installing the bag body into the vertical drainage pipe (17) and the horizontal drainage pipe (18), setting the grouting pipe (16) at the center position inside the bag body of the vertical drainage pipe (17), and filling the bag body of the horizontal drainage pipe (18) with coarse sand (28); 3) Dig steps on the surface of the landslide foundation and lay anti-seepage geotextile (14); 4) A self-setting mortar groove is excavated at the toe of the upper slope of the designed embankment fill. The bottom of the groove penetrates the weak sliding layer (3) and is embedded in the bedrock (1) to a certain depth. The self-setting mortar is poured into the groove. 5) Construct bored cast-in-place piles as anti-slide piles at the anti-slide pile design locations (11); 6) Drilling a hole with a vertical drilling rig and hoisting a vertical drainage pipe (17) with a crane, filling the vertical drainage pipe (17) with gravel (27), and connecting a section of cable (25) to the top of the vertical drainage pipe (17); 7) Drilling a hole with a horizontal drilling rig and manually inserting a transverse drainage pipe (18), and connecting a section of cable (25) to the outlet of the transverse drainage pipe (18); 8) Connecting the top of each row of vertical drainage pipes (17) to a horizontal drainage branch pipe, each drainage branch pipe is connected to a drainage main pipe arranged along the longitudinal direction of the embankment, the drainage branch pipes are arranged in a stepped manner along the transverse direction of the embankment according to the elevation of the top of the vertical drainage pipes, the drainage main pipe is arranged outside the embankment, and the drainage main pipe is connected to a vacuum pump (21) to pump water; 9) connecting the cable (25) at the top of each row of vertical drainage pipes (17) to the wire (19), so that the cables (25) at the tops of two adjacent rows of vertical drainage pipes (17) are connected to different wires (19), and the wires (19) of two adjacent rows of vertical drainage pipes (17) are respectively connected to the anode and cathode of a direct current power supply (20), and the direct current power supply (20) is turned on for electroosmosis, and the voltage is controlled within 36V; 10) connecting the cable (25) of each row of transverse drainage pipes (18) to the conductor (19), so that the cable (25) of two adjacent rows of transverse drainage pipes (18) are connected to different conductors (19), and the conductors (19) of two adjacent rows of transverse drainage pipes (18) are respectively connected to the anode and cathode of a direct current power supply (20), and the direct current power supply (20) is turned on for electroosmosis, and the voltage is controlled within 36V; 11) After the water output of the electroosmotic drainage is significantly reduced, the cable (25) and the DC power supply (20) of the horizontal drainage pipe (18) are removed, and the DC power supply (20) and the vacuum pump (21) of the vertical drainage pipe (17) are retained to continue to work, and the gravel layer (15) is filled and compacted; 12) filling the embankment soil (6) in layers, and after filling to a certain height, removing the cable (25), the DC power supply (20) and the vacuum pump (21) connected to the vertical drainage pipe (17), connecting the grouting pipe (16) of the vertical drainage pipe (17) to the grouting pump, and injecting cement slurry into the vertical drainage pipe (17); 13) Remove the grouting pipe (16) and the grouting pump, and continue to fill the embankment fill (6) to the designed elevation. Set a step on the top of the embankment fill (6) and lay an anti-seepage geotextile (14). Also lay an anti-seepage geotextile (14) on the side slopes of the embankment fill (6). 14) Casting a plain concrete anti-pressure berm (12) at the lower slope foot of the embankment fill (6); 15) hoisting the first-stage precast reinforced concrete retaining wall, pouring foamed concrete (10) inside the first-stage precast reinforced concrete retaining wall, and setting settlement joints during pouring; 16) hoisting the second-level precast reinforced concrete retaining wall, inserting the embedded screw rod (22) on the top of the first-level precast reinforced concrete retaining wall into the connection hole of the bottom plate of the second-level precast reinforced concrete retaining wall, fixing it with an anchor head (23), and pouring foam concrete (10) on the inner side of the second-level precast reinforced concrete retaining wall; 17) Hoist the third-level prefabricated reinforced concrete retaining wall and pour foam concrete (10) as needed; 18) A road surface (8) is constructed on top of the foamed concrete (10), and the elevation of the road surface (8) is lower than the elevation of the prefabricated reinforced concrete retaining wall (24) by a certain distance.

2. The construction method of the embankment structure for treating landslide foundation according to claim 1 is characterized by: The anti-slide pile (11) is a bored cast-in-place pile with a square or circular cross-section.

3. The construction method of the embankment structure for treating landslide foundation according to claim 1 is characterized by: A drainage ditch (13) is provided at the bottom of the gravel layer (15).

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