Land-saving, deformation-reducing, green and low-carbon roadbed structure

Abstract

The utility model relates to the technical field of roadbed engineering, in particular to a land-saving, deformation-reducing, green and low-carbon roadbed structure which comprises concrete filled steel tube stirring composite sparse and long piles, criss-cross pile top lattice beams and a wrapped reinforced side slope, the concrete-filled steel tube mixing composite sparse and long piles are arranged at the bottoms of the pile top lattice beams and located at the joint positions of the pile top lattice beams, the wrapped reinforced slope is arranged above the pile top lattice beams, and each concrete-filled steel tube mixing composite sparse and long pile comprises an external mixing pile body and an internal core pile. The core pile is of a steel pipe concrete structure. The utility model has the advantages that the deformation is reduced, the external environment influence resistance of the roadbed is improved, the land is reduced, the concrete consumption is reduced, the manufacturing cost is reduced, the masonry consumption is reduced, and the low-carbon and environment-friendly effects are realized.

Description

Technical Field

[0001] The utility model relates to the technical field of subgrade engineering, in particular to a subgrade structure that saves land, reduces deformation, and is green and low-carbon. Background Art

[0002] At present, in China's subgrade engineering, especially high-speed railway subgrade engineering, there are problems such as wide subgrade occupation, large amount of masonry protection, many uncertain factors in later settlement control, and large investment, resulting in an increasingly small proportion of subgrade engineering, especially high-speed railway subgrade engineering, in the project. Specifically:

[0003] 1) At present, the slope ratio of the subgrade slope is generally not steeper than 1:1.5. Compared with bridges, the land occupation is relatively large. As China's land resources are becoming increasingly tense and land prices are getting higher and higher, the cost of subgrade land acquisition is extremely high.

[0004] 2) Due to the high requirements for subgrade settlement in high-speed railway operation, the commonly used subgrade foundation reinforcement technologies such as CFG piles and pipe piles have limited reinforcement depth, generally not exceeding 30m. As a result, in some subgrade sections, due to the influence of external environments such as groundwater level fluctuations after operation, deformation occurs, affecting the operation of high-speed railways.

[0005] 3) At present, the amount of masonry used for subgrade slope protection is relatively large, which does not meet the current national requirements for green and low-carbon. Summary of the Invention

[0006] The purpose of the utility model is to provide a subgrade structure that saves land, reduces deformation, and is green and low-carbon according to the deficiencies of the above-mentioned existing technologies. By adopting the structural form of steel tube concrete mixing composite piles combined with pile top grid beams, while effectively reducing subgrade settlement, effectively reducing the influence of groundwater level fluctuations on subgrade deformation, and effectively improving the ability of the subgrade to cope with external environmental changes, the subgrade slope ratio and land occupation are reduced.

[0007] The purpose of the utility model is achieved by the following technical solutions:

[0008] A subgrade structure that saves land, reduces deformation, and is green and low-carbon, characterized in that: it includes steel tube concrete mixing composite long and thin piles, vertically and horizontally crisscrossed pile top grid beams, and wrapped reinforced slopes. The steel tube concrete mixing composite long and thin piles are arranged at the bottom of the pile top grid beams and located at the node positions of the pile top grid beams. The wrapped reinforced slopes are arranged above the pile top grid beams. The steel tube concrete mixing composite long and thin piles include an external mixing pile body and an internal core pile, and the core pile is a steel tube concrete structure.

[0009] A steel reinforcement cage is arranged inside the core pile of the steel tube concrete mixing composite long and thin pile, and the steel reinforcement cage is connected with the steel bars of the pile top grid beam to form an integral structure.

[0010] A compaction layer is provided on the upper part of the pile top lattice beam, and the compaction layer is located between the pile top lattice beam and the wrapped reinforced slope.

[0011] The compaction layer includes a filler layer, and a layer of high-strength geogrid, a layer of high-strength geocell and a layer of high-strength geogrid are clamped in the filler layer from bottom to top.

[0012] The wrapped reinforced slope includes a fill, a wrapper and a geosynthetic layer. The wrapper is arranged on the side of the fill, the geosynthetic layer wraps the wrapper, and adjacent upper and lower geosynthetic layers are connected by fasteners.

[0013] Footwalls are provided on both sides of the pile top lattice beam, and the footwalls and the pile top lattice beam form an integral structure.

[0014] A drainage ditch and a fence are sequentially arranged outward on the outer side of the footwall.

[0015] The advantages of the present utility model are as follows:

[0016] 1) Reducing deformation and increasing the ability of the subgrade to resist the influence of the external environment: The steel tube concrete mixing composite pile is used for foundation reinforcement, and the long and sparse pile structure (pile length above 30m, pile spacing 4 - 6m) is adopted, so that the subgrade can achieve the purpose of deep treatment under relatively economical conditions, reduce the settlement deformation of the subgrade, and greatly enhance the anti-deformation ability of the subgrade when resisting external environmental changes such as groundwater decline after the subgrade is built.

[0017] 2) Reducing land use: The wrapped reinforced slope structure is adopted, and the slope ratio can be reduced from the conventional 1:1.5 to 1:0.5 - 1:1; after the integral footwall is adopted at the slope toe, the drainage ditch and the fence can be set closer to the slope toe, and these measures can greatly reduce the land use of the subgrade project.

[0018] 3) The pile top lattice beam + compaction layer structure reduces the concrete consumption and lowers the cost: Different from the conventional sparse pile structure where a reinforced concrete raft slab structure is required at the pile top, the reinforced concrete lattice beam + geosynthetic compaction layer is used as the pile top structure, which fully applies the stress dispersion and soil arch effect of the compaction layer, reduces the concrete consumption at the pile top, reduces the project investment, and conforms to the low-carbon environmental protection policy.

[0019] 4) Reducing the masonry work amount and being low-carbon and environmentally friendly: After the wrapped reinforced structure is adopted for the slope, the masonry protection is not required, which greatly reduces the concrete consumption of the subgrade project and conforms to the low-carbon environmental protection policy. Description of the Drawings

[0020] Figure 1 It is a structural schematic diagram of the present utility model;

[0021] Figure 2 Construction process of the present utility model Figure Ⅰ ;

[0022] Figure 3 Construction process of the present utility model Figure Ⅱ Top view;

[0023] Figure 4 Construction process of the present utility model Figure Ⅱ Partial enlarged view;

[0024] Figure 5 Construction process of the present utility model Figure Ⅲ ;

[0025] Figure 6 Construction process of the present utility model Figure Ⅳ ;

[0026] Figure 7 Construction process of the present utility model Figure Ⅳ Partial enlarged view;

[0027] Figure 8 Construction process of the present utility model Figure Ⅴ 。 Specific embodiments

[0028] The features of the present utility model and other related features will be further described in detail below with reference to the accompanying drawings through embodiments, so as to facilitate the understanding of those skilled in the same industry:

[0029] As Figures 1-8 shown, the marks 1-16 in the figure respectively represent: concrete-filled steel tube mixing composite long pile 1, pile top grid beam 2, wrapped reinforced slope 3, compacted layer 4, fill 5, foot wall 6, steel reinforcement cage 7, steel bar 8, filler layer 9, high-strength geogrid 10, high-strength geocell 11, wrapper 12, geosynthetic layer 13, fastener 14, drainage ditch 15, fence 16.

[0030] Embodiment: As Figures 1 to 8 shown, the subgrade structure that saves land, reduces deformation, and is green and low-carbon in this embodiment mainly includes concrete-filled steel tube mixing composite long pile 1, pile top grid beam 2, wrapped reinforced slope 3, and compacted layer 4.

[0031] Among them, each concrete-filled steel tube mixing composite long pile 1 as a pile foundation is arranged at the bottom of the whole. It includes an outer mixing pile body and a concrete-filled steel tube core pile arranged in the mixing pile body. The concrete-filled steel tube core pile includes a steel tube inserted in the mixing pile body and concrete poured into the steel tube. By designing the concrete-filled steel tube mixing composite long pile 1, the subgrade settlement can be effectively reduced, the influence of groundwater level rise and fall on subgrade deformation can be effectively reduced, and the ability of the subgrade to cope with external environmental changes can be effectively improved.

[0032] The pile top lattice beam 2 is arranged at the top position of each concrete-filled steel tube mixing composite long pile 1, and is arranged in a crisscross pattern and covers the range of the overlying wrapped reinforced slope 3. Each concrete-filled steel tube mixing composite long pile 1 is arranged at the center of the crisscross nodes of the pile top lattice beam 2.

[0033] In this embodiment, the pile top frame beam 2 adopts a reinforced concrete structure, and the steel bars 8 inside it are connected with the steel bar cage 7 arranged in the core pile of the lower concrete-filled steel tube mixing composite long pile 1 to form an integral structure; after construction is completed, the pile top lattice beam 2 and each concrete-filled steel tube mixing composite long pile 1 are connected into an integral structure, thereby improving the overall structural performance.

[0034] Foot walls 6 are arranged on both sides of the pile top lattice beam 2 and form an integral structure with it. The compacted layer 4 is arranged above the pile top lattice beam 2 and between the foot walls 6 on both sides. The compacted layer 4 includes a filler layer 9, a high-strength geogrid 10, and a high-strength geocell 11. Among them, the filler layer 9 is composed of high-quality fillers such as crushed stone soil or improved soil. A layer of high-strength geogrid 10, a layer of high-strength geocell 11, and another layer of high-strength geogrid 10 are sequentially clamped from bottom to top in the filler layer 9, thereby improving the structural performance of the compacted layer. By adopting the pile top structure composed of the pile top lattice beam 2 and the compacted layer 4, the pile top stress can be effectively dispersed, the amount of pile top concrete can be reduced, the cost can be reduced, and the requirements of national green and low-carbon are met.

[0035] The wrapped reinforced slope 3 includes a fill 5, a wrapper 12, a geosynthetic layer 13, and fasteners 14. Among them, the fill 5 constitutes the main structure of the slope, and the wrapper 12 such as a geotextile bag is arranged on its side. The wrapper 12 is wrapped back by the geosynthetic layer 13 such as a geogrid and a geotextile, and the two geosynthetic layers 13 are connected by fasteners 14. Through the wrapped reinforced slope structure form, the slope ratio of the subgrade slope can be made as steep as 1:0.5 - 1:1, reducing land occupation; at the same time, the slope can only adopt green protection and not masonry protection, reducing the amount of masonry, meeting the requirements of national green and low-carbon.

[0036] In this embodiment, a drainage ditch 15 and a fence 16 are sequentially arranged outward on the outside of the foot wall 6. The drainage ditch 15 plays a drainage role, and the fence 16 plays a role of enclosure; at this time, since the foot wall 6 and the pile top lattice beam 2 are set as an integral structure, the drainage ditch 15 and the fence 16 can be closer to the foot wall 6, further reducing the subgrade land occupation.

[0037] This embodiment can be widely applied to various subgrade projects, especially high-speed railway subgrades, reducing subgrade land use, increasing the ability of the subgrade to resist external environmental changes, reducing subgrade investment, and having a wide application prospect.

[0038] Although the above embodiments have described in detail the concept and embodiments of the object of the present utility model with reference to the accompanying drawings, those of ordinary skill in the art can recognize that various improvements and modifications can still be made to the present utility model without departing from the scope defined by the claims, so they will not be elaborated one by one here.

Claims

1. A land-saving, deformation-reducing, green and low-carbon roadbed structure, characterized by: It includes a steel tube concrete mixing composite sparse pile, a crisscross pile top frame beam, and a wrapped reinforced slope. The steel tube concrete mixing composite sparse pile is arranged at the bottom of the pile top frame beam and is located at the node position of the pile top frame beam. The wrapped reinforced slope is arranged above the pile top frame beam. The steel tube concrete mixing composite sparse pile includes an external mixing pile body and an internal core pile, and the core pile is a steel tube concrete structure.

2. The land-saving, deformation-reducing, green and low-carbon roadbed structure according to claim 1 is characterized by: A steel cage is arranged inside the core pile of the steel tube concrete mixing composite elongated pile, and the steel cage is connected with the steel bars of the pile top frame beam to form an integral structure.

3. The land-saving, deformation-reducing, green and low-carbon roadbed structure according to claim 1 is characterized by: A hardened layer is arranged on the upper part of the pile top frame lattice beam, and the hardened layer is located between the pile top frame lattice beam and the wrapped reinforced slope.

4. The land-saving, deformation-reducing, green and low-carbon roadbed structure according to claim 3 is characterized by: The compacted layer comprises a filler layer, in which a layer of high-strength geogrid, a layer of high-strength geocell and a layer of high-strength geogrid are sandwiched from bottom to top.

5. The land-saving, deformation-reducing, green and low-carbon roadbed structure according to claim 1 is characterized by: The wrapped reinforced slope includes fill, a wrapping body and a geotechnical material layer. The wrapping body is arranged at the side of the fill, and the geotechnical material layer wraps the wrapping body. The upper and lower adjacent geotechnical material layers are connected by fasteners.

6. The land-saving, deformation-reducing, green and low-carbon roadbed structure according to claim 1 is characterized by: Foot walls are arranged on both sides of the pile top frame beam, and the foot walls and the pile top frame beam form an integral structure.

7. The land-saving, deformation-reducing, green and low-carbon roadbed structure according to claim 6 is characterized by: The outer side of the foot wall is provided with drainage ditches and fences in sequence.

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