Composite foundation treatment structure for deep soft soil area of low-fill high-standard racing track
By adopting low-fill composite foundation treatment structures in the deep soft soil areas of high-standard tracks, including multi-layer structures and CFG pile reinforcement, the problem of difficulty in meeting the ultra-high speed environment and strict settlement control in the existing technology is solved, and the stability and economicality of the roadbed are achieved.
Patent Information
- Application Number
- CN202421455408.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-25
- Publication Date
- 2025-05-06
- Estimated Expiration
- 2034-06-25
AI Technical Summary
When building high-standard tracks in the southeast coast and the Yangtze River Basin, existing foundation treatment methods are difficult to meet the requirements of ultra-high-speed environment and strict settlement control, and the commonly used methods are time-consuming and costly, making it difficult to ensure the stability of the roadbed.
The composite foundation treatment structure is adopted for the deep soft soil area of the low-fill high-standard track, including the road structure layer set from top to bottom, the second layer of cement stabilized soil, the third layer of geogrid, the first layer of cement stabilized soil, the second layer of geogrid, the gravel cushion layer, the first layer of geogrid, the foundation reinforcement, and the filling and excavation slope. The foundation reinforcement includes multiple CFG piles.
It significantly reduces the sliding force of the soil slope, enhances the stability of the fill slope, reduces uneven settlement of the road surface, reduces process difficulty and cost, and is suitable for foundation treatment in deep soft soil areas of high-standard tracks.
Smart Images
Figure CN222834866U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of foundation and basic engineering, and in particular to a composite foundation treatment structure in a deep soft soil area of a low-fill high-standard racetrack. Background Art
[0002] With the continuous development of national economic construction and the acceleration of urbanization, my country's road traffic engineering construction has been carried out on a large scale. However, there are a large number of deep soft clay layers distributed in the southeastern coast and the Yangtze River Basin of my country, and the engineering properties are poor. When building roads in these areas, if the soft foundation is not properly treated, it is very easy to cause embankment instability and post-construction settlement and differential settlement problems. Conventional soft soil foundations mostly use preloading method, vacuum preloading method, vacuum-preloading combined preloading method, cement soil mixing pile composite foundation, high-pressure jet grouting pile composite foundation, rigid pile composite foundation, etc., and have achieved good results. Although there are many kinds of foundation treatment methods available, for deep soft soil areas such as ultra-high-speed environments of racing tracks (vehicle speeds of 300km / h and above), strict settlement control requirements (post-construction settlement does not exceed 5cm), and low fill sections of embankments (not exceeding 3m), methods such as preloading, vacuum preloading, and vacuum-preloading combined preloading are time-consuming and have a large labor cost. The quality of composite foundations such as cement-soil mixing piles and high-pressure rotary jet piles is difficult to guarantee, and the cost of rigid pile composite foundations is high. In addition, the roadbed fillers used in the past are difficult to guarantee the compaction quality, which seriously restricts the healthy development of high-grade road projects. Utility Model Content
[0003] The purpose of the utility model is to overcome the shortcomings of the above-mentioned background technology and to provide a composite foundation treatment structure for deep soft soil areas of a low-fill high-standard track, so that the sliding force of the soil slope can be significantly reduced, thereby enhancing the stability of the fill slope, greatly reducing the uneven settlement of the road surface, and the process difficulty and cost are well controlled.
[0004] The utility model provides a composite foundation treatment structure for deep soft soil areas of a low-fill high-standard track, comprising: a road structure layer, a second layer of cement stabilized soil, a third layer of geogrid, a first layer of cement stabilized soil, a second layer of geogrid, a crushed stone cushion, a first layer of geogrid, a foundation reinforcement body, and fill slopes and excavation slopes on both sides, wherein the foundation reinforcement body comprises a foundation soil body and a plurality of CFG piles arranged in the foundation soil body.
[0005] The beneficial effects of the utility model are as follows: the composite foundation treatment structure of the deep soft soil area of the low-fill high-standard track of the utility model can easily penetrate the soft soil layer to reach the soil layer with relatively high bearing capacity, and has the advantages of small settlement, stable and fast deformation, etc. At the same time, the construction operation is simple, the construction period is short, the quality is controllable, the construction is environmentally friendly, and the economy is good. It is especially suitable for the foundation treatment of deep soft soil areas of high-standard tracks with embankment fill height not exceeding 3m (vehicle speed exceeds 300km / h, and post-construction settlement does not exceed 5cm), and provides a safe, reasonable and reliable solution for the design of composite foundation treatment structures in deep soft soil areas under complex geological conditions.
[0006] On the basis of the above technical solution, the present invention can also be improved as follows:
[0007] Further: the fill slope has a gradient of 1:2, the fill slope height is the distance from the existing ground surface to the top surface of the road structure layer, the planting soil layer containing vegetation is arranged above the fill slope on both sides, and the planting soil layer containing vegetation is located on one side of the fill slope.
[0008] Furthermore: the slope of the excavation slope is 1:1.5, and the excavation depth is the distance from the existing ground surface to the top of the CFG pile body.
[0009] The beneficial effect of the above further scheme is that by slowing down the slope of the fill and excavation slopes, the sliding force of the soil slope can be significantly reduced, thereby enhancing the stability of the fill slope. At the same time, by filling the fill slope with a planting soil layer containing vegetation and supplementing it with a certain soil stabilizer, water, etc. according to the ratio, it can not only complete the green ecological construction and improve the aesthetics of the slope, but also reduce the erosion of the slope surface by rainwater, further playing the role of soil consolidation.
[0010] Furthermore: the CFG pile includes a CFG pile body and a CFG pile cap, the CFG pile body is vertically buried in the foundation soil, the CFG pile cap is arranged on the top of the CFG pile body by cast-in-place concrete, the upper end of the CFG pile body extends into the CFG pile cap, and the CFG pile body and the CFG pile cap are cast by C30 concrete, so that the CFG pile body and the CFG pile cap form a whole.
[0011] The beneficial effect of the above further scheme is: by mixing crushed stone, stone chips, sand, fly ash, cement and water to form a CFG pile body with high bonding strength, and then connecting the CFG pile body with the CFG pile cap and pouring concrete, the CFG pile body is vertically buried in the foundation soil, which greatly improves the compression modulus and bearing capacity of the composite foundation, reduces the risk of uneven settlement of the soft foundation, and thus ensures the stability of the roadbed.
[0012] Further: the CFG pile cap includes a frame and a pile cap body, the frame is arranged at the upper end of the pile cap body, and the frame and the pile cap body are cast by concrete to form the CFG pile cap.
[0013] The beneficial effect of the above further solution is that the skeleton and the pile cap body are integrally formed by pouring concrete, which can ensure the firmness and uniform force of the CFG pile body and ensure the stability of the CFG pile body and the entire CFG pile structure.
[0014] Further: the crushed stone cushion layer is located on the top of the CFG pile.
[0015] The beneficial effect of the above further scheme is: by laying a crushed stone cushion layer on the top of the pile, the sharing of pile and soil load can be adjusted, the joint effect of the pile and the soil between the piles can be fully utilized, the pile-soil stress ratio can be effectively reduced, and the load can be transferred to the deep foundation, reducing the unevenness of the foundation and achieving coordinated deformation of the foundation.
[0016] Further: the first layer of geogrid is set at 30 cm above the top of the CFG pile cap, the second layer of geogrid is set at the boundary between the first layer of cement stabilized soil and the crushed stone cushion layer, the third layer of geogrid is set at the boundary between the first layer of cement stabilized soil and the second layer of cement stabilized soil, and the geogrid is a polypropylene three-way geogrid.
[0017] The beneficial effect of the above further scheme is: by arranging a three-way geogrid on the top of the CFG pile cap, the force on the pile body and the top of the soil between the piles is made more uniform. At the same time, by arranging the three-way geogrid at the boundary between the cement stabilized soil and the gravel cushion layer, and at the boundary between the first layer of cement stabilized soil and the second layer of cement stabilized soil, the three-way geogrid is fully utilized to exert its large tensile strength in the longitudinal, transverse and three-dimensional directions, greatly enhancing the friction of the medium at the boundary between the cement stabilized soil and the gravel cushion layer, avoiding the loss of roadbed soil particles, and then reducing the risk of roadbed settlement.
[0018] Further: the cement stabilized soil includes the first layer of cement stabilized soil and the second layer of cement stabilized soil. The first layer of cement stabilized soil is located above the gravel cushion layer, and the second layer of cement stabilized soil is located between the first layer of cement stabilized soil and the road structure layer, as well as below the planting soil layer containing vegetation on both sides. The cement stabilized soil should be backfilled and compacted in layers, and the compacted thickness of each layer shall not exceed 20 cm.
[0019] The beneficial effect of the above further scheme is: by backfilling and compacting the cement stabilized soil in layers, the treated cement stabilized soil reaches a sufficient density, thereby improving the overall stability and firmness of the roadbed, ensuring the safe operation of vehicle loads, avoiding deterioration of operating conditions due to long-term subsidence, and greatly reducing uneven settlement of the road surface. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 It is a schematic diagram of the overall structure of the composite foundation treatment structure of the deep soft soil area of the low-fill high-standard track of the utility model;
[0021] Figure 2 It is a schematic diagram of the plane arrangement of CFG piles in the composite foundation treatment structure of the deep soft soil area of the low-fill high-standard track of the utility model;
[0022] Figure 3 It is a schematic diagram of the reinforcement of the CFG pile cap of the CFG pile in the composite foundation treatment structure of the deep soft soil area of the low fill high standard track of the utility model. DETAILED DESCRIPTION
[0023] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments, but the embodiments should not be construed as limiting the present invention.
[0024] like Figure 1 As shown, a composite foundation treatment structure for deep soft soil areas of a low-fill high-standard track comprises: a road structure layer 3, a second layer of cement stabilized soil 4, a third layer of geogrid 8, a first layer of cement stabilized soil 7, a second layer of geogrid 9, a crushed stone cushion layer 11, a first layer of geogrid 10, a foundation reinforcement body, and fill slopes 2 and excavation slopes 6 inclined on both sides of the road structure layer 3, the foundation reinforcement body comprising a foundation soil body 13, and a plurality of end bearing piles or friction piles arranged in the foundation soil body 13, and the end bearing piles or friction piles are CFG piles.
[0025] The composite foundation treatment structure in deep soft soil areas of low-fill high-standard tracks of the utility model can easily penetrate soft soil layers to reach soil layers with relatively high bearing capacity, and has the advantages of small settlement, stable and fast deformation, etc. At the same time, the construction operation is simple, the construction period is short, the quality is controllable, the construction is environmentally friendly, and the economy is good. It is especially suitable for foundation treatment in deep soft soil areas of high-standard tracks (vehicle speed exceeds 300km / h, and post-construction settlement does not exceed 5cm) with embankment fill height not exceeding 3m, and provides a safe, reasonable and reliable solution for the design of composite foundation treatment structures in deep soft soil areas under complex geological conditions.
[0026] In one or more embodiments of the present invention, the distance between the fill slopes 2 on both sides presents a trapezoidal structure in which the top distance is smaller than the bottom distance, the slope of the fill slope 2 is 1:2, the height of the fill slope 2 is the distance from the existing ground surface 1 to the top surface of the road structure layer 3, the planting soil layer 5 containing vegetation is arranged above the fill slopes 2 on both sides, and the planting soil layer 5 containing vegetation is located on the outside of the outer wall of the fill slope 2; the distance between the excavation slopes 6 on both sides presents an inverted trapezoidal structure in which the top distance is greater than the bottom distance, the slope is 1:1.5, and the excavation depth is the distance from the existing ground surface 1 to the top of the CFG pile body 14; by slowing down the slopes of the fill and excavation slopes, the sliding force of the soil slope can be significantly reduced, thereby enhancing the stability of the fill slope 2. At the same time, by filling the fill slope 2 with a planting soil layer 5 containing vegetation and supplementing it with a certain proportion of soil stabilizer, water, etc., not only can the green ecological construction be completed and the aesthetics of the slope be improved, but also the erosion of the slope surface by rainwater can be reduced, thereby further achieving the effect of soil consolidation.
[0027] In one or more embodiments of the present invention, the CFG pile includes a CFG pile body 14 and a CFG pile cap 12, the CFG pile body 14 is vertically buried in the foundation soil 13, the CFG pile cap 12 is arranged on the top of the CFG pile body 14 by cast-in-place concrete, the upper end of the CFG pile body 14 extends into the CFG pile cap 12, the upper part of the CFG pile cap 12 extends into the gravel cushion layer 11, and the CFG pile body 14 and the CFG pile cap 12 are cast by C30 concrete, so that the CFG pile body 14 and the CFG pile cap 12 form a whole. The CFG pile body 14 and the CFG pile cap 12 are an integrally cast structure. A CFG pile body 14 with high bonding strength is formed by mixing crushed stone, stone chips, sand, fly ash, cement and water, and then the CFG pile body 14 is connected to the CFG pile cap 12, and concrete is poured. The CFG pile body 14 is vertically buried in the foundation soil 13, which greatly improves the compression modulus and bearing capacity of the composite foundation, reduces the risk of uneven settlement of the soft foundation, and thus ensures the stability of the roadbed.
[0028] Specifically, the diameter of the CFG pile is 60 cm, the cement in the CFG pile uses ordinary Portland cement with a strength grade of 42.5, and the concrete strength of the pile body should reach C20.
[0029] Specifically, Figure 2 As shown, the arrangement of the multiple end bearing piles or friction piles is to be arranged vertically and horizontally and extend in all directions, and the vertical and horizontal intervals between adjacent end bearing piles or friction piles are equal. In this embodiment, the end bearing piles or friction piles, such as CFG piles, are arranged in a square shape with a pile spacing of 2m, and the CFG pile body 14 enters the CFG pile cap 12 to a depth of 50cm.
[0030] Specifically, the fly ash material in CFG piles should be grade III or above fly ash with a fineness (0.045mm square hole sieve residue percentage) not exceeding 45%, and the fly ash dosage per cubic meter should be 80kg.
[0031] Specifically, the maximum particle size of the gravel in the CFG pile is no more than 20 mm.
[0032] Specifically, the sand content in the CFG pile is not more than 5%.
[0033] Specifically, the inspection frequency of CFG pile position is 2%, the allowable deviation of pile position is 10cm, and the pile diameter and pile length should not be less than the design value.
[0034] Specifically, the CFG pile body 14 vertically penetrates the soft soil layer and enters the plastic-hard plastic clay layer or sand layer in the foundation soil body 13 to a depth of not less than 1 m.
[0035] In one or more embodiments of the present invention, the CFG pile cap 12 includes a skeleton and a pile cap body, the skeleton is arranged at the middle of the upper end of the pile cap body, and the skeleton and the pile cap body are poured with concrete to form the CFG pile cap 12. The skeleton and the pile cap body formed by pouring concrete together constitute the integral CFG pile cap 12, which can ensure the firmness and uniform force of the CFG pile body 14, and ensure the stability of the CFG pile body 14 and the entire CFG pile structure.
[0036] In practice, if Figure 3 As shown, the skeleton is composed of a plurality of circular pile cap top longitudinal bars 15, a plurality of pile cap bottom longitudinal bars 16, a plurality of pile cap side longitudinal bars 17, a plurality of pile cap tension bars 18 and a plurality of pile cap stirrups 19. A plurality of pile cap side longitudinal bars 17 are uniformly distributed along the circumferential direction and connect the pile cap top longitudinal bars 15 and the pile cap bottom longitudinal bars 16 between the outermost pile cap top longitudinal bars 15 and the outermost pile cap bottom longitudinal bars 16. A plurality of circles of pile cap tension bars 18 are uniformly distributed along the circumferential direction and connect the pile cap top longitudinal bars 15 and the pile cap bottom longitudinal bars 16 between the inner circle pile cap top longitudinal bars 15 and the corresponding pile cap bottom longitudinal bars 16. A plurality of pile cap stirrups 19 which are annular as a whole are respectively provided at the top and bottom ends of the plurality of pile cap side longitudinal bars 17. The plurality of pile cap top longitudinal bars 15 and the pile cap bottom longitudinal bars 16 are horizontally spaced apart, and then the pile cap as a whole with a protective layer is formed by pouring concrete.
[0037] Specifically, the CFG pile cap 12 has a size of 100 cm×100 cm×30 cm.
[0038] Specifically, the steel bar protection layer thickness of the CFG pile cap 12 is 50 cm.
[0039] Furthermore: the gravel cushion layer 11 is located on the top of the CFG pile. By laying the gravel cushion layer 11 on the top of the pile, the sharing of pile and soil loads can be adjusted, the combined effect of the pile and the soil between the piles can be fully utilized, the pile-soil stress ratio can be effectively reduced, and the load can be transferred to the deep foundation, reducing the unevenness of the foundation and achieving coordinated deformation of the foundation.
[0040] Specifically, the crushed stone cushion layer 11 has a thickness of 60 cm and a compaction coefficient of not less than 0.96.
[0041] Specifically, the maximum particle size of the crushed stone cushion layer 11 is not greater than 20 mm.
[0042] In one or more embodiments of the utility model, the first geogrid 10 is arranged at a position 30 cm above the top of the CFG pile cap 12, the second geogrid 9 is arranged at the boundary between the first cement stabilized soil 7 and the crushed stone cushion layer 11, and the third geogrid 8 is arranged at the boundary between the first cement stabilized soil 7 and the second cement stabilized soil 4, and the geogrid is a polypropylene three-dimensional geogrid. By arranging the three-dimensional geogrid on the top of the CFG pile cap 12, the pile body and the top of the soil between the piles are subjected to more uniform force. At the same time, by arranging the three-dimensional geogrid at the boundary between the cement stabilized soil and the crushed stone cushion layer 11, and at the boundary between the first cement stabilized soil 7 and the second cement stabilized soil 4, the tensile strength in the longitudinal, transverse and three-dimensional directions is fully utilized, and the friction of the medium at the boundary between the cement stabilized soil and the crushed stone cushion layer 11 is greatly enhanced, thereby avoiding the loss of roadbed soil particles and reducing the risk of roadbed settlement.
[0043] Specifically, the quality-controlled tensile modulus of the first geogrid layer 10, the second geogrid layer 9, and the third geogrid layer 8 should not be less than 185 kN / m / 2%.
[0044] Specifically, the cross-sections of the first geogrid layer 10, the second geogrid layer 9, and the third geogrid layer 8 are rectangular, the inner holes are equilateral triangles, and the outer sides are regular hexagons.
[0045] Optionally, in one or more embodiments of the utility model, cement stabilized soil includes the first layer of cement stabilized soil 7 and the second layer of cement stabilized soil 4, the first layer of cement stabilized soil 7 is located above the gravel cushion layer 11, the second layer of cement stabilized soil 4 is located between the first layer of cement stabilized soil 7 and the road structure layer 3, and below the planting soil layer 5 containing vegetation on both sides, and the cement stabilized soil should be backfilled and rolled in layers, and the compacted thickness of each layer is not more than 20 cm. By backfilling and compacting the cement stabilized soil in layers, the treated cement stabilized soil reaches a sufficient density, improves the overall stability and firmness of the roadbed, ensures the safe operation of vehicle loads, avoids the deterioration of operating conditions due to long-term subsidence, and greatly reduces the uneven settlement of the road surface.
[0046] Specifically, the thickness of the first layer of cement stabilized soil 7 is 30 cm, and the thickness of the second layer of cement stabilized soil 4 is the distance between the first layer of cement stabilized soil 7 and the road structure layer 3.
[0047] Specifically, the compaction degree of the first cement stabilized soil layer 7 is not less than 0.94, and the compaction degree of the second cement stabilized soil layer 4 within 1.5 m of the roadbed top is not less than 0.97 and the compaction degree of the area greater than 1.5 m is not less than 0.96.
[0048] Specifically, the cement in the first layer of cement stabilized soil 7 and the second layer of cement stabilized soil 4 is 42.5 ordinary Portland cement with an initial setting time greater than 3 hours and a final setting time not less than 6 hours, and the cement content is 7%.
[0049] Specifically, the uniformity coefficient of the first layer of cement-stabilized soil 7 and the second layer of cement-stabilized soil 4 should be greater than 10, the liquid limit should be no greater than 40%, and the plasticity index should be 10-17.
[0050] The specific implementation steps of the composite foundation treatment structure of the low-fill high-standard track deep soft soil area of the utility model are as follows:
[0051] Step 1: Survey the site, clear obstacles that may affect pile foundation construction, determine the starting position of construction, earthwork construction boundaries, and machinery travel routes, etc.
[0052] Step 2: Excavate the slope to the designed elevation according to the designed slope and level the top of the pile.
[0053] Step 3: Remove obstacles such as plant roots, stones, bricks, concrete blocks, and underground abandoned buildings (structures) that affect pile construction;
[0054] Step 4: laying the gravel cushion layer 11, compacting it, and then constructing the CFG pile body 14;
[0055] Step 5: After the CFG pile body 14 is constructed and tested to be qualified, the CFG pile cap 12 is cast, and then the first layer of geogrid 10 is laid, and the crushed stone cushion layer 11, the second layer of geogrid 9 and the first layer of cement stabilized soil 7 are laid, and the first layer of cement stabilized soil 7 is backfilled and rolled in layers;
[0056] Step 6: After the first layer of cement stabilized soil 7 is completed and tested to be qualified, the third layer of geogrid 8 is laid, and the second layer of cement stabilized soil 4 is continued to be laid, and the second layer of cement stabilized soil 4 is backfilled and rolled in layers;
[0057] Step 7: After the construction of the cement stabilized soil is completed and tested to be qualified, the road structure layer 3, the planting soil layer 5 containing vegetation and other road facilities are constructed.
[0058] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.
[0059] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.
Claims
1. A composite foundation treatment structure for a low-fill high-standard track in a deep soft soil area, located between the existing ground surfaces (1) on both sides, characterized by: The invention comprises a road structure layer (3), a second layer of cement stabilized soil (4), a third layer of geogrid (8), a first layer of cement stabilized soil (7), a second layer of geogrid (9), a first layer of geogrid (10), a crushed stone cushion layer (11) and a foundation reinforcement body, which are arranged in sequence from top to bottom. The road structure layer (3) is provided with fill slopes (2) arranged in an inclined manner on both sides. The second layer of cement stabilized soil (4), the third layer of geogrid (8), the first layer of cement stabilized soil (7), the second layer of geogrid (9), the first layer of geogrid (10) and the crushed stone cushion layer (11) are provided with excavation slopes (6) on both sides. The distance between the fill slopes (2) on both sides presents a trapezoidal structure in which the top distance is smaller than the bottom distance. A planting soil layer (5) is provided on the outer side wall of the fill slope (2). The distance between the excavation slopes (6) on both sides presents an inverted trapezoidal structure in which the top distance is larger than the bottom distance.
2. The composite foundation treatment structure for deep soft soil area of low fill high standard track according to claim 1 is characterized by: The foundation reinforcement body comprises a foundation soil body (13) and a plurality of end bearing piles or friction piles arranged in the foundation soil body (13).
3. The composite foundation treatment structure for deep soft soil area of low fill high standard track according to claim 2 is characterized by: The plurality of end bearing piles or friction piles are arranged in a longitudinal and transverse manner and are extended in all directions, and the longitudinal and transverse intervals between adjacent end bearing piles or friction piles are equal.
4. The composite foundation treatment structure for deep soft soil area of low fill high standard track according to claim 3 is characterized by: The end bearing pile or friction pile is a CFG pile.
5. The composite foundation treatment structure for deep soft soil area of low fill high standard track according to claim 4 is characterized by: Each CFG pile comprises a CFG pile body (14) and a CFG pile cap (12) located at the top of the CFG pile body (14); the top of the CFG pile body (14) extends into the CFG pile cap (12); the upper part of the CFG pile cap (12) extends into the gravel cushion layer (11); and the CFG pile body (14) and the CFG pile cap (12) are an integrally cast structure.
6. The composite foundation treatment structure for deep soft soil area of low fill high standard track according to claim 5 is characterized by: The CFG pile cap (12) comprises a frame and a pile cap body, the frame is arranged in the middle of the pile cap body, and the frame and the pile cap body formed by concrete pouring together constitute the CFG pile cap (12).
7. The composite foundation treatment structure for deep soft soil area of low fill high standard track according to claim 6 is characterized by: The frame has a plurality of pile cap top longitudinal bars (15) located at the upper part of the frame, and the frame has a plurality of pile cap bottom longitudinal bars (16) located at the lower part of the frame. A plurality of pile cap side longitudinal bars (17) uniformly distributed along the circumferential direction and connecting the pile cap top longitudinal bars (15) and the pile cap bottom longitudinal bars (16) are provided between the outermost pile cap top longitudinal bars (15) and the outermost pile cap bottom longitudinal bars (16). A plurality of pile cap tension bars (18) uniformly distributed along the circumferential direction and connecting the pile cap top longitudinal bars (15) and the pile cap bottom longitudinal bars (16) are provided between the inner circle pile cap top longitudinal bars (15) and the corresponding pile cap bottom longitudinal bars (16). A plurality of pile cap hoop bars (19) in an overall annular shape are provided at the top and bottom ends of the plurality of pile cap side longitudinal bars (17).
8. The composite foundation treatment structure for deep soft soil area of low fill high standard track according to claim 7 is characterized by: The slope of the fill slope (2) is 1:2, and the slope of the cut slope (6) is 1:1.5.