Flexible water and ice storage slope protection retaining wall

Abstract

The utility model relates to a flexible water and ice storage slope protection retaining wall, and belongs to the technical field of civil engineering. In order to overcome the defects existing in the prior art, the flexible water and ice storage slope protection retaining wall comprises a retaining wall body structure and a drainage ditch adjacent to the outer side of the retaining wall body structure, the retaining wall body structure comprises a gabion set, the gabion set comprises a plurality of gabions arranged from top to bottom, and the gabions are arranged in the drainage ditch. The gabion is filled with aggregate, and galvanized steel wire rings are arranged on the outer side and the bottom of the gabion set. The drainage ditch comprises a side ditch, a seepage ditch located below the side ditch and a drainage pipe buried in the seepage ditch. The utility model provides an integrated retaining wall structure which has an ice retaining function in a high-altitude area and a water and soil protection capability of a cut slope. The slope retaining structure is suitable for slope retaining protection of a water-rich slope with a seasonal freezing and thawing phenomenon in a high-altitude or alpine region.

Description

Technical Field

[0001] The utility model relates to a flexible water and ice storage slope retaining wall, belonging to the technical field of civil engineering, in particular to the construction of roads, railways, water conservancy projects in water-rich areas in high altitude or cold regions. Background Art

[0002] In high-altitude or cold water-rich slopes, seasonal drizzling ice often occurs in winter. Its ice bodies accumulate with the infiltration of flowing water, often forming icicles of considerable area, increasing the protective pressure of retaining facilities; when the water outflow is large, it often flows to the road surface, forming freezing, which seriously affects road driving safety. The existing products on the market are mostly designed based on retaining structures or water dam structures, and can only protect slopes of soil, water, or water-rich rock and soil. In actual applications in high-altitude areas, especially in gullies and cuttings with rich water flow, the frost heave effect of surface and shallow surface water bodies in winter has not been fully considered, resulting in strong frost heave compression of existing retaining wall products, resulting in structural damage or destruction.

[0003] The commonly used ice retaining wall structure is based on non-contact prevention of the slope, so the cutting slope is not effectively supported. Coupled with water erosion, it often collapses and deforms.

[0004] At present, the two support and protection technologies for frozen slopes are: plain concrete or rubble concrete retaining wall structure; technology 2: wire mesh stone cage (gabion stone cage) retaining wall structure.

[0005] The existing technology uses plain concrete or rubble concrete materials, and strives to use concrete materials with good integrity and high structural strength to form a gravity retaining wall to resist the water and soil pressure of the slope. In winter, the retaining wall needs to withstand the frost heave force after the water freezes into ice. At the same time, concrete or rubble concrete materials often suffer from fatigue cracking and structural damage during the seasonal freeze-thaw cycle, and lose the existing design function. Therefore, the commonly used ice retaining wall structure often does not directly contact the seepage slope, leaving a certain space for drainage and ice release, and only plays a certain ice retaining and water retaining function, and the slope support capacity is completely lost.

[0006] At the same time, the overall cost of plain concrete or rubble concrete is relatively high, especially in high-altitude or cold areas, where the quality of concrete materials is difficult to guarantee during construction under low temperature conditions.

[0007] The second existing technology is to enhance the ability of gravity retaining walls to resist fatigue damage, and a wire mesh stone cage (gabion stone cage) retaining wall structure is formed. A composite gravity protection structure is formed by using a gabion cage with good corrosion resistance + piece stone or pebble filler. This technology uses piece stone or pebble with a larger particle size (an average of about 10 to 20 cm) for filling, and the water-facing surface is very permeable. However, during the freezing period of high-altitude water-rich sections, water from the slope often easily seeps out from the gaps in the filling stones and flows to the road surface to form an icy road surface, seriously threatening road driving safety. Utility Model Content

[0008] In order to overcome the defects in the prior art, the utility model aims to provide a flexible water and ice storage slope retaining wall.

[0009] The utility model provides a technical solution to solve the above technical problems: a flexible water and ice storage slope retaining wall, including a retaining wall structure and a drainage ditch adjacent to the outer side of the retaining wall structure, the retaining wall structure includes a gabion gabion group, the gabion gabion group includes a plurality of gabions arranged from top to bottom, the gabions are filled with aggregates, and galvanized steel wire rings are provided on the outer side and bottom of the gabion gabion group; the drainage ditch includes a side ditch, a seepage ditch located below the side ditch, and a drainage pipe buried in the seepage ditch.

[0010] A further technical solution is that the galvanized steel wire ring is hinged to the gabion cage.

[0011] A further technical solution is that the galvanized steel wire ring includes a gabion cage protective cover and a composite geotextile layer attached to the inner side of the gabion cage protective cover.

[0012] A further technical solution is that the gabion cage protective cover is a galvanized steel wire mesh.

[0013] A further technical solution is that the composite geotextile layer includes an anti-seepage geomembrane layer, a honeycomb fiber mesh layer, a geobubble membrane layer, and a water-permeable geotextile layer, which are arranged in sequence from top to bottom.

[0014] A further technical solution is that a plurality of gabion stone cages are stacked in an upper and lower plane or in an upper and lower stepped stacking arrangement.

[0015] A further technical solution is that the cage body material of the gabion stone cage is galvanized steel wire with a tensile strength of 500N / mm 2 , elongation is not less than 10%, and the double-wire twisted length is not less than 3cm.

[0016] A construction method for a flexible water and ice storage slope retaining wall comprises the following steps:

[0017] Step 1: Dig the cut slope and jump the trench;

[0018] Step 2: Determine the minimum bearing capacity of the foundation according to the wall height and perform foundation treatment;

[0019] Step 3: After the foundation treatment is completed, dig a side ditch, set a crushed stone seepage ditch under the side ditch, and bury a corrugated pipe with holes;

[0020] Step 4: Lay the base waterproof layer;

[0021] Step 5: Splice the bottom layer of gabion stone cage skeleton, then fill the aggregate, stagger the layers layer by layer, and stack the gabion stone cages after the stone cage units are completed;

[0022] Step 6: Lay out the geotextile layer. The length and width of the single layer are 5 to 10 cm longer than the length and width of the retaining wall facade. Unfold it layer by layer. Use galvanized steel rings to fix the geotextile layer and the outer gabion stone cage protective cover on the set gabion stone cage body to complete the dressing shape.

[0023] Step 7: Complete the connection between the remaining side ditches and retaining wall ends.

[0024] A further technical solution is that the aggregate pebbles or block stones have a median particle size of 20 cm, the porosity of the pebbles is 20% to 30%, and the porosity of the block stones is 15% to 25%.

[0025] A further technical solution is that the calculation formula for the minimum bearing capacity of the foundation is:

[0026] F a =50(H-3)+200

[0027] Where: F a is the minimum bearing capacity of the foundation, kPa; H is the height of the wall, m.

[0028] A further technical solution is that the specific process of step 4 is: spreading the composite geotextile layer evenly on the base, with the laying width bent inwardly to the slope surface, leaving a surplus of 20 cm.

[0029] The utility model has the following beneficial effects: the utility model provides an integrated retaining wall structure, which has both ice-blocking function in high-altitude areas and water and soil protection ability in cutting slopes. It is suitable for slope support and protection in high-altitude or cold areas where water-rich slopes have seasonal freeze-thaw phenomena. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a cross-sectional schematic diagram of an implementation example 1 of the utility model;

[0031] Figure 2 This is a cross-sectional schematic diagram of implementation case 2 of the utility model;

[0032] Figure 3This is a large-scale drawing of the barrier structure of the utility model;

[0033] Figure 4 This is a schematic diagram of the structure of the gabion stone cage of the utility model;

[0034] Figure 5 This is a schematic diagram of the composite geotextile layer structure of the utility model.

[0035] As shown in the figure: 1. Slope gully (with flowing water); 2. Gabion stone cage; 3. Composite geotextile layer; 31. Anti-seepage geomembrane layer; 32. Honeycomb fiber mesh layer; 33. Geobubble membrane layer; 34. Permeable geotextile layer; 4. Side ditch; 5. Road surface; 6. Seepage ditch; 7. Drainage pipe; 8. Aggregate; 9. Water seepage in the slope; 10. Gabion stone cage protective cover. DETAILED DESCRIPTION

[0036] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0037] like Figure 1 , 2 As shown, a flexible water storage and ice storage slope retaining wall of the utility model includes a retaining wall structure outside the slope surface and a drainage ditch adjacent to the outside of the wall. The slope surface can be close to the retaining wall structure. The retaining wall structure is arranged in the form of a road cutting retaining wall. Depending on the terrain and geological conditions, a 0.5-1.5m flange burial depth is retained. A plane stacking type ( Figure 1 ), or a stepped stack ( Figure 2 ); the drainage ditch comprises a side ditch 4, a seepage ditch 6 and a drainage pipe 7 buried in the seepage ditch 6, wherein the seepage ditch 6 is arranged below the side ditch 4;

[0038] The retaining wall structure includes a gabion gabion group, wherein the gabion gabion group includes a plurality of gabion gabions 2 arranged from top to bottom, and the gabion gabions 2 are filled with aggregate 8;

[0039] The utility model gabion stone cage structure schematic diagram is as follows Figure 4 As shown, the cage body material of the gabion stone cage is galvanized steel wire with a tensile strength of 500N / mm 2 , elongation is not less than 10%, double-wire twisted length is not less than 3cm, mesh diameter is 6cm, it has the characteristics of high strength, fatigue resistance, corrosion resistance and long life.

[0040] The gabion stone cage 2 used in the wall structure of the utility model can be plane-type (upward-inclined type, vertical type), can also be spliced ​​in a stepped manner, and can also be freely combined and spliced ​​in stone cage sizes according to terrain conditions.

[0041] like Figure 3 and Figure 4 As shown, galvanized steel wire rings are provided on the outside and bottom of the gabion gabion group, and the galvanized steel wire rings include a gabion gabion protective cover 10 and a composite geotextile layer 3, and the gabion gabion protective cover 10 is a galvanized steel wire mesh.

[0042] The galvanized steel wire mesh is attached to the composite geotextile layer 3 and installed and disassembled together to ensure the extension and stability of the geotextile.

[0043] The galvanized steel wire mesh can refer to the material specifications used for gabion cages. By hingedly connecting the galvanized steel wire ring with the rectangular gabion cage body, it can be freely installed and disassembled from the cage body. The galvanized steel wire ring is a common installation accessory for the composite geotextile layer 3 and the galvanized steel wire mesh. After the galvanized steel wire mesh and the composite geotextile layer 3 are bonded together, they are installed and disassembled together to ensure the extension and stability of the geotextile.

[0044] like Figure 5 As shown, in this embodiment, one implementation of the composite geotextile layer 3 includes an anti-seepage geomembrane layer 31, a honeycomb fiber mesh layer 32, a geobubble membrane layer 33, and a water-permeable geotextile layer 34, which are arranged in sequence from top to bottom.

[0045] In actual use, the implementation method of this embodiment can be selected according to actual conditions, and a single-layer or multi-layer permeable geotextile or a single-layer or multi-layer anti-seepage geomembrane can also be used.

[0046] A construction method for a flexible water and ice storage slope retaining wall comprises the following steps:

[0047] Step 1: Dig the cut slope and jump the trench;

[0048] Step 2: Determine the minimum bearing capacity of the foundation according to the wall height and perform foundation treatment;

[0049] F a =50(H-3)+200

[0050] Where: F a is the minimum bearing capacity of the foundation, kPa; H is the height of the wall, m;

[0051] Step 3: After the foundation treatment is completed, dig a side ditch, set a crushed stone seepage ditch under the side ditch, and bury a corrugated pipe with holes;

[0052] Step 4: Spread the composite geotextile layer 3 evenly on the base, with the laying width bent inwards and close to the slope surface, leaving a surplus of 20 cm;

[0053] Step 5, splicing the bottom gabion stone cage skeleton, and then filling with aggregate (the aggregate floating pebble material or piece stone material, the median particle size of which is 20cm, the porosity of the floating pebble material is 20% to 30%, and the porosity of the piece stone material is 15% to 25%), staggering and arranging layer by layer, and after the stone cage unit is completed, stacking the gabion stone cages;

[0054] Step 6: Lay out the geotextile layer 3. The length and width of the single-layer fabric are 5 to 10 cm longer than the length and width of the retaining wall facade. Unfold it layer by layer, and use galvanized steel rings to fix the geotextile layer 3 and the outer gabion stone cage protective cover on the set gabion stone cage body to complete the dressing shape.

[0055] Step 7: Complete the connection between the remaining side ditches and retaining wall ends.

[0056] Implementation principle:

[0057] The utility model has both the general cutting slope protection function and the water and ice storage function.

[0058] The basic principle of the utility model to realize the general slope protection is to balance the soil by relying on the overall gravity of the wall structure. The calculation principle is based on the basic principle of soil mechanics: the soil pressure takes into account the active soil pressure. Because the wall is a highly permeable material, water is quickly drained away, and dynamic or static water pressure can be ignored. The resistance of the retaining wall is mainly the passive soil pressure provided by the friction force at the bottom of the wall and the buried depth of the collar:

[0059] According to the force polygon theory, the calculation principle under non-seismic conditions is briefly described. The active earth pressure E a :

[0060]

[0061] Where: G is the deadweight of the fractured wedge; c is the equivalent cohesion of the slope rock and soil; is the equivalent internal friction angle of the slope rock and soil; θ is the angle between the fracture wedge and the horizontal plane; δ is the friction angle between the back of the retaining wall and the fracture wedge; l is the length of the fracture surface of the fracture wedge;

[0062] The basic principle of the utility model to achieve the function of storing water and ice is to set a geotextile structure layer on the far slope side and the bottom of the wall. The geotextile can be selected according to the actual water output and the construction cost-effectiveness. Since the main aggregate of the retaining wall is a large-size piece of stone or floating pebble, its permeability coefficient is much greater than the permeability coefficient of the geotextile structure. After the slope water or seepage water enters the wall, it will be greatly restricted at the geotextile structure, and most of it will be retained in the aggregate pores, and move along the vertical direction and parallel to the wall surface, so as to achieve the ability of storing water and ice. Excess water will soak the geotextile structure or be discharged along the side ditch close to the wall.

[0063] The wall volume is V, the filler porosity is n, the porosity of the pebble material is controlled at 20%-30%, and the porosity of the block stone is controlled at 15%-25%. The full load capacity of the pebble material retaining wall for storing water and ice is (0.2-0.3)V, and the full load capacity of the pebble material retaining wall for storing water and ice is (0.15-0.25)V. Under full storage conditions, the frost heave rate of ice is 9%, and the frost heave rate of the frozen wall is 0.09n.

[0064] The geotextile structure layer on the outside of the wall body mainly considers the permeability coefficient to be much smaller than the wall aggregate. Therefore, whether it is a permeable geotextile structure or an impermeable geotextile structure, or a flexible filling filter layer with a low permeability coefficient, the required function can be achieved. Therefore, the material itself only needs to meet the requirements of environmental protection and durability, and the structure layer is a detachable structure for later replacement. The default wall body geotextile structure layer is set to the far slope side (outside) of the wall body and the bottom of the wall, which can achieve the minimum requirements required by the principle of this utility model.

[0065] In order to better improve the durability of the material, it is recommended that the geotechnical structure of the utility model meet the following requirements: the longitudinal and transverse fracture strength should not be less than 20kN / m, the elongation corresponding to the nominal fracture strength should not be less than 80%, the bursting strength should not be less than 3.2kN, the longitudinal and transverse tearing strength should not be less than 0.5kN / m, the acid and alkali resistance (strength retention rate) should not be less than 80%, the oxidation resistance (strength retention rate) should not be less than 80%, and the UV resistance (strength retention rate) should not be less than 80%. 85 0.07~0.20mm can be selected according to the needs, and the vertical permeability K (value range 1.0~9.9) reference index is (10 -1 ~10 -3 )K.

[0066] Example 1

[0067] The construction site is located in Gonggar County, Tibet Autonomous Region, with high mountain canyon landforms, an average altitude of 3700m, and an average winter temperature of -10 to -20℃. The site is a national highway cutting, with an average slope height of 5m and a natural slope of about 45°. The gullies flow all year round and freeze in winter. The surface is Quaternary loose gravel soil, and the main geological diseases are saliva ice and shallow landslides. Due to the large amount of water discharge in this section, the surface water freezes in winter, and the highway's own drainage facilities can no longer meet the normal drainage needs. The excess water overflows to the road surface to form an icy road surface, posing a great safety hazard.

[0068] Analyzing the topographic and geological conditions of the construction site, it is found that the drainage system of the highway facilities cannot be further enhanced due to the narrow route corridor. It is necessary to enhance the drainage capacity of the slope and the road cutting protection at the same time, and consider implementing the water storage and ice retaining wall involved in the utility model for treatment.

[0069] 1) Excavation of the cut slope and the existing roadbed is soaked in water all year round, and the gravel is replaced with the wall height of 4m. The bearing capacity of the foundation reaches 350kPa after treatment, which is greater than the F calculated by the empirical formula. a =250kPa.

[0070] 2) Side ditch: After the foundation treatment is completed, the side ditch is dug, and a crushed stone seepage ditch is set under the side ditch. At the same time, a corrugated pipe with holes is buried to further enhance the drainage capacity of the side ditch structure.

[0071] 3) Bottom waterproof layer: Lay the base waterproof layer. This project is located in a remote area, with cold winters and strong freezing force. Considering comprehensive considerations, a double-layer permeable geotextile can be used. Spread the geotextile structure in layers and spread it flat on the base. The laying width is bent inwards and close to the slope surface, leaving a surplus of 20cm.

[0072] 4) After the base geotextile is fully spread, the bottom gabion frame is spliced, and then the aggregate is filled: the aggregate is selected according to the construction area and the floating pebbles (median particle size 20cm) are staggered layer by layer. After the gabion unit is completed, the wire gabion layer is stacked. The overall facade of the gabion is flat ( Figure 1 ).

[0073] 5) Continue to lay out the high-impermeability composite antifreeze structural geotextile. The length and width of the single-layer fabric should be 5 to 10 cm longer than the length and width of the retaining wall facade. Unfold it layer by layer, and use galvanized steel rings to fix the composite geotextile layer 3 and the outer stone cage cover surface on the set lead wire gabion body to complete the dressing shape.

[0074] 6) Improve the connection of remaining side ditches and retaining wall ends.

[0075] Example 2

[0076] The construction site is located in Muli County, Liangshan Yi Autonomous Prefecture, Sichuan Province, with high mountain canyon landforms, an average altitude of 2,500m, and an average winter temperature of -2 to 8°C. The site is a provincial highway cutting with an average slope height of 6m, a natural slope of about 50°, and gullies with water flowing all year round. The surface is Quaternary loose gravel soil, and the main geological disease is shallow landslide. Due to the narrow terrain conditions in this section, the highway's own drainage facilities can no longer meet the normal drainage needs. Excess water overflows to the road surface and forms dark ice at night in winter, posing a great safety hazard.

[0077] Analyzing the topographic and geological conditions of the construction site, it is found that the drainage system of the highway facilities cannot be further enhanced due to the narrow route corridor. It is necessary to enhance the drainage capacity of the slope and the road cutting protection at the same time, and consider implementing the water storage and ice retaining wall involved in the utility model for treatment.

[0078] 1) Excavation of the cut slope and the existing roadbed is soaked in water all year round. Replacement of qualified fillers is carried out. The wall height is 4m. The bearing capacity of the foundation reaches 300kPa after treatment, which is greater than the F calculated by the empirical formula.a =250kPa.

[0079] 2) Side ditch: After the foundation treatment is completed, the side ditch is dug, and a crushed stone seepage ditch is set under the side ditch. At the same time, a 110 perforated corrugated pipe is buried to further enhance the drainage capacity of the side ditch structure.

[0080] 3) Bottom waterproof layer: Lay the base waterproof layer. The water output of this project is large, and the freezing phenomenon in winter is mainly dark ice before sunrise. Consider setting a high-impermeability composite antifreeze structure geotextile layer to greatly control the slope seepage within the retaining wall-drainage ditch drainage system. From the inside of the slope to the outside of the slope (along the direction of water flow), it is: anti-seepage geomembrane layer 31, honeycomb fiber mesh layer 32, geotextile bubble membrane layer 33, and permeable geotextile layer 34. Spread the geotextile structure in layers and spread it flat on the base. The laying width is bent toward the inside of the slope and close to the slope surface, with a surplus of 20 cm.

[0081] 4) After the base geotextile is fully spread, the bottom gabion frame is spliced, and then the aggregate is filled: the aggregate is selected according to the construction area and the block stone (median particle size 20cm) is staggered layer by layer. After the gabion unit is completed, the wire gabion layer is stacked. The overall facade of the gabion is stepped ( Figure 2 );

[0082] 5) Continue to lay out the high-impermeability composite antifreeze structural geotextile. The length and width of the single-layer fabric are 5 to 10 cm longer than the length and width of the retaining wall facade. Unfold it layer by layer, and use galvanized steel rings to fix the composite geotextile layer 3 and the outer stone cage surface on the set lead wire gabion body to complete the dressing shape;

[0083] 6) Improve the connection of remaining side ditches and retaining wall ends.

[0084] The above description does not impose any form of limitation on the present invention. Although the present invention has been disclosed through the above embodiments, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are within the scope of the technical solution of the present invention.

Claims

1. A flexible water and ice storage slope retaining wall, characterized in that: The invention comprises a retaining wall structure and a drainage ditch adjacent to the outer side of the retaining wall structure, wherein the retaining wall structure comprises a gabion gabion cage group, wherein the gabion gabion cage group comprises a plurality of gabion gabions (2) arranged from top to bottom, wherein the gabion gabions (2) are filled with aggregate (8), and the outer side and bottom of the gabion gabion cage group are provided with galvanized steel wire rings; the drainage ditch comprises a side ditch (4), a seepage ditch (6) located below the side ditch (4), and a drainage pipe (7) buried in the seepage ditch (6).

2. A flexible water and ice storage slope retaining wall according to claim 1, characterized in that: The galvanized steel wire ring is hinged to the gabion cage (2).

3. A flexible water and ice storage slope retaining wall according to claim 2, characterized in that: The galvanized steel wire ring comprises a gabion gabion protective cover (10) and a composite geotextile layer (3) attached to the inner side of the gabion gabion protective cover (10).

4. The flexible water and ice storage slope retaining wall according to claim 3 is characterized in that: The gabion cage protective cover (10) is a galvanized steel wire mesh.

5. The flexible water and ice storage slope retaining wall according to claim 3 is characterized in that: The composite geotextile layer (3) comprises an anti-seepage geomembrane layer (31), a honeycomb fiber mesh layer (32), a geobubble membrane layer (33), and a water-permeable geotextile layer (34) which are arranged in sequence from top to bottom.

6. The flexible water and ice storage slope retaining wall according to claim 1, characterized in that: A plurality of gabion stone cages (2) are arranged in an upper and lower plane stacking arrangement or an upper and lower stepped stacking arrangement.

7. The flexible water and ice storage slope retaining wall according to claim 1, characterized in that: The cage body material of the gabion stone cage (2) is galvanized steel wire with a tensile strength of 500N / mm 2 , elongation is not less than 10%, and the double-wire twisted length is not less than 3cm.

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