Structure and construction method for preventing differential settlement of new roadbed and old roadbed of extended road
By adopting step-like structures and rigid layer structures in the reconstruction and expansion of highways, the problem of differential settlement of new and old roadbeds is solved, and the uniform load distribution of new roadbeds and the improvement of the bearing capacity of the roadbed is achieved, thereby avoiding differential settlement of new and old roadbeds.
Patent Information
- Application Number
- CN202510536938.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-27
- Publication Date
- 2025-06-20
AI Technical Summary
During the highway renovation and expansion process, there is an uneven settlement problem between the new and old roadbeds, resulting in overall settlement or side-slip settlement. How to avoid differential settlement of new and old roadbeds has become an urgent problem to be solved.
A structure and construction method to prevent the differential settlement of new and old roadbeds on the expanded road are adopted, including digging a stepped structure on one side of the original roadbed, laying a homogeneous layer and a rigid layer structure, and laying the new roadbed layers in sequence on the side of the rigid layer structure away from the original roadbed, and improving the bearing capacity of the roadbed through the new roadbed rigid layer to avoid differential settlement of new and old roadbeds.
By evenly distributing the road surface load and lateral soil pressure, prevent local stress failure and settlement of the original roadbed, improve the bearing capacity of the new roadbed, reduce the settlement of the new roadbed, and thus avoid differential settlement of the new and old roadbeds.
Smart Images
Figure CN120174680A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of highway engineering, and in particular relates to a structure and a construction method for preventing differential settlement of new and old roadbeds of an expanded road. Background Art
[0002] With the increase in the number of cars, the original number of lanes in the original highway design is too small and can no longer meet the growing demand for vehicle traffic, so it needs to be rebuilt and expanded. The roadbed of the non-elevated highway section needs to be widened on one side based on the original old roadbed to form a new roadbed; because the old roadbed has been compacted for a long time, its settlement during subsequent use is small, while the new fill expansion roadbed has not been compacted for a long time. Therefore, after the highway reconstruction and expansion is completed, there will inevitably be uneven settlement between the new and old roadbeds during use, the new roadbed itself has overall settlement or uneven settlement, or the new roadbed has side sliding settlement and many other problems. How to avoid uneven settlement of the new and old roadbeds has become an urgent problem to be solved. Therefore, we propose a structure and construction method to prevent differential settlement of the new and old roadbeds of the expanded road. Summary of the invention
[0003] The purpose of the present invention is to provide a structure and a construction method for preventing differential settlement of new and old roadbeds of an expanded road, so as to solve the above-mentioned problem.
[0004] To achieve the above object, the present invention provides the following solutions:
[0005] A structure for preventing differential settlement between new and old roadbeds of an expanded road, comprising:
[0006] A stepped structure is opened on one side of the original roadbed, the stepped structure has a plurality of stepped horizontal surfaces and stepped vertical surfaces, and the stepped structure is used to connect with the new roadbed;
[0007] A uniform layer structure is laid on the stepped horizontal surface;
[0008] A rigid layer structure is laid outside the plurality of force-averaging layer structures and the plurality of stepped vertical surfaces, the rigid layer structure is stepped, the rigid layer structure is fixedly connected to the original roadbed via a fixing portion, and the new roadbed is laid on a side of the rigid layer structure away from the original roadbed;
[0009] The new roadbed includes a new roadbed base layer, a cushion structure, a lifting layer, a new roadbed rigid layer and a new road surface which are arranged in sequence from bottom to top. The top surface of the new road surface is at the same horizontal height as the top surface of the original road surface. The new road surface is spliced with the original road surface, and a slope protection covering layer is laid on one side of the new roadbed.
[0010] Optionally, the force-averaging layer structure includes:
[0011] The coal gangue bearing layer is laid on the stepped horizontal plane.
[0012] Optionally, the coal gangue bearing layer is formed by compacting a mixture of coal gangue and fly ash.
[0013] Optionally, by mass parts, the raw materials of the coal gangue bearing layer include:
[0014] 70 - 85 parts of coal gangue, 10 - 20 parts of fly ash, 5 - 10 parts of lime, 0 - 5 parts of natural soil.
[0015] Optionally, the rigid layer structure is a stepped concrete covering layer, and a number of parallel steel bars are embedded in the stepped concrete covering layer.
[0016] Optionally, the above fixing part includes a number of anchor rods. One end of the anchor rod passes through the vertical section of the corresponding stepped concrete covering layer and the stepped vertical plane, and then inserts into the original roadbed. The anchor rod is fixedly connected to the stepped concrete covering layer.
[0017] Optionally, the cushion layer structure includes a second waterproof layer, a graded coal gangue layer, and a first waterproof layer arranged in sequence from bottom to top. The second waterproof layer is laid on the top surface of the bottom layer of the new roadbed.
[0018] Optionally, the lifting layer is a mixture of graded gravel, coal gangue, and fly ash.
[0019] Optionally, by mass parts, the raw materials of the rigid layer of the new roadbed include:
[0020] 70 - 80 parts of coal gangue, 10 - 20 parts of sand, 5 - 8 parts of cement, 3 - 5 parts of fly ash, 2 - 4 parts of lime, 5 - 10 parts of water.
[0021] A construction method for a structure for preventing differential settlement between new and old roadbeds in an expanded road, used for manufacturing the above - mentioned structure for preventing differential settlement between new and old roadbeds in an expanded road, includes the following steps:
[0022] Dig out the stepped structure on one side of the original roadbed;
[0023] Lay the equal - force layer structure on the stepped horizontal plane;
[0024] Cover the rigid layer structure outside the equal - force layer structure, and use the fixing part to fix the rigid layer structure to the original roadbed;
[0025] Lay and compact the bottom layer of the new roadbed, the cushion layer structure, the lifting layer, the rigid layer of the new roadbed, and the new road surface in sequence on the side of the rigid layer structure away from the original roadbed, and lay a slope protection soil covering layer on one side of the formed new roadbed.
[0026] Compared with the prior art, the present invention has the following advantages and technical effects:
[0027] During use, a stepped structure is dug on one side of the original roadbed, the equalizing layer structure is laid on the stepped horizontal plane, the rigid layer structure is covered outside the equalizing layer structure, and the fixing part is used to fix the rigid layer structure to the original roadbed; through such a setting, the road surface load and the lateral earth pressure received by the new road surface can be evenly distributed on the original roadbed, preventing local stress damage and settlement of the original roadbed. On the side of the rigid layer structure away from the original roadbed, the new roadbed bottom layer, cushion structure, lifting layer, new roadbed rigid layer and new road surface are sequentially laid and compacted, and a slope protection soil covering layer is laid on one side of the formed new roadbed. The bearing capacity of the roadbed is improved by the new roadbed rigid layer to reduce the settlement of the new road surface, thereby avoiding differential settlement between the new and old roadbeds. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings:
[0029] Figure 1 It is a schematic structural diagram of the present invention;
[0030] Figure 2 It is a random distribution diagram of the water-containing capsule balls in the new roadbed rigid layer of the present invention;
[0031] Among them, 1, original road surface; 2, original roadbed; 3, new road surface; 4, new roadbed rigid layer; 5, lifting layer; 6, waterproof layer 1; 7, graded coal gangue layer; 8, waterproof layer 2; 9, new roadbed bottom layer; 10, slope protection soil covering layer; 11, stepped concrete covering layer; 12, coal gangue bearing layer; 13, steel bars; 14, anchor bolts; 15, water-containing capsule balls. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.
[0033] To make the above objects, features and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the drawings and specific embodiments.
[0034] Refer toFigures 1 to 2 , the present invention discloses a structure for preventing differential settlement between new and old roadbeds during road expansion, including:
[0035] A stepped structure is opened on one side of the original roadbed 2. The stepped structure has several stepped horizontal planes and stepped vertical planes, and the stepped structure is used to connect with the new roadbed;
[0036] An equalizing layer structure is laid on the stepped horizontal plane;
[0037] A rigid layer structure is laid outside several equalizing layer structures and several stepped vertical planes. The rigid layer structure is stepped, and the rigid layer structure is fixedly connected to the original roadbed 2 through a fixing part. The new roadbed is laid on the side of the rigid layer structure away from the original roadbed 2;
[0038] The new roadbed includes a new roadbed bottom layer 9, a cushion structure, a lifting layer 5, a new roadbed rigid layer 4, and a new road surface 3 arranged in sequence from bottom to top. The top surface of the new road surface 3 is at the same horizontal height as the top surface of the original road surface 1. The new road surface 3 is spliced with the original road surface 1, and a slope protection soil covering layer 10 is laid on one side of the new roadbed.
[0039] During use, a stepped structure is excavated on one side of the original roadbed 2, the equalizing layer structure is laid on the stepped horizontal plane, the rigid layer structure is covered outside the equalizing layer structure, and the rigid layer structure is fixed to the original roadbed 2 using a fixing part; by setting like this, the road surface load and lateral earth pressure received by the new road surface 3 can be evenly distributed on the original roadbed 2, preventing local stress damage and settlement of the original roadbed 2. On the side of the rigid layer structure away from the original roadbed 2, the new roadbed bottom layer 9, the cushion structure, the lifting layer 5, the new roadbed rigid layer 4, and the new road surface 3 are laid and compacted in sequence, and a slope protection soil covering layer 10 is laid on one side of the formed new roadbed. The bearing capacity of the roadbed is improved through the new roadbed rigid layer 4 to reduce the settlement of the new road surface 3, thereby avoiding differential settlement between the new and old roadbeds.
[0040] As an alternative embodiment, the equalizing layer structure includes:
[0041] A gangue pressure-bearing layer 12 is laid on the stepped horizontal plane.
[0042] As an alternative embodiment, the gangue pressure-bearing layer 12 is formed by compacting a mixture of gangue and fly ash.
[0043] As an alternative embodiment, by mass fraction, the raw materials of the gangue pressure-bearing layer 12 include:
[0044] 70 - 85 parts of gangue, 10 - 20 parts of fly ash, 5 - 10 parts of lime, and 0 - 5 parts of natural soil.
[0045] The slope of the original roadbed 2 is excavated into a stepped structure, and the gangue bearing layer 12 is laid at the steps to form a mechanical interlocking interface, and the shear strength of the interface is increased by 20%-30%.
[0046] The gangue has the following advantages as a differential settlement prevention filling layer:
[0047] Lightweight and high strength: Through gradation optimization and lightweight modification, the dual requirements of mechanical properties and load reduction are met;
[0048] Environmental protection and economy: The resource utilization of solid waste significantly reduces costs and carbon emissions;
[0049] Engineering adaptability: Characteristics such as water permeability and humidity adjustment, and frost resistance in cold regions adapt to complex environments;
[0050] Long-term stability: Creep characteristics and chemical stability ensure the performance of the road throughout its life cycle.
[0051] The natural bulk density of gangue is 1.6 - 1.8 g / cm 3 , which is much lower than that of traditional sand and gravel fillers (2.0 - 2.2 g / cm 3 ). After filling, the self-weight of the new roadbed is reduced by 10%-20%, significantly reducing the additional load and lateral thrust on the old roadbed. After the gangue is crushed and screened, the angular particles form a "skeleton-dense" structure through reasonable gradation (the proportion of particles larger than 4.75 mm is 40%-60%). After compaction, the CBR value can reach 8%-15%, and the shear strength is increased to 35-40 kPa, which can significantly enhance the anti-slip ability of the joint surface between the new and old roadbeds.
[0052] As an alternative implementation, the rigid layer structure is a stepped concrete covering layer 11, and several parallel steel bars 13 are embedded in the stepped concrete covering layer 11.
[0053] As an alternative implementation, the fixing part includes several anchor bolts 14. One end of the anchor bolt 14 passes through the vertical section of the corresponding stepped concrete covering layer 11 and the stepped vertical surface, and then inserts into the original roadbed 2, and the anchor bolt 14 is fixedly connected to the stepped concrete covering layer 11.
[0054] As an alternative implementation, the cushion layer structure includes a second waterproof layer 8, a graded gangue layer 7, and a first waterproof layer 6 arranged in sequence from bottom to top. The second waterproof layer 8 is laid on the top surface of the bottom layer 9 of the new roadbed.
[0055] As an alternative implementation, the lifting layer 5 is a mixture of graded gravel, gangue, and fly ash.
[0056] As an alternative implementation, by mass, the raw materials of the rigid layer 4 of the new roadbed include:
[0057] 70 - 80 parts of coal gangue, 10 - 20 parts of sand, 5 - 8 parts of cement, 3 - 5 parts of fly ash, 2 - 4 parts of lime, 5 - 10 parts of water.
[0058] As an additional implementation method, calculated by mass parts, the raw materials of the new roadbed rigid layer 4 include:
[0059] 65 - 70 parts of coal gangue, 8 - 10 parts of cement, 10 - 12 parts of fly ash, 5 - 8 parts of graded broken stone, 2 - 3 parts of water, 1 - 1.5 parts of antifreeze.
[0060] As an additional implementation method, water is filled into the water-containing capsule ball 15, and the water-containing capsule ball 15 is mixed with coal gangue, cement, fly ash, graded broken stone and antifreeze.
[0061] As an additional implementation method, the water-containing capsule ball 15 is made of modified gelatin, the particle size of the water-containing capsule ball 15 is 2 - 5 mm, and the water content of the water-containing capsule ball 15 is 0.3 g.
[0062] During use, first mix the dry materials such as coal gangue, crushed stone, cement, fly ash, etc., and the stirring time is ≥ 3 min. Finally, add the water-containing capsule ball 15, and the stirring time is ≤ 1 min, and the rotation speed is ≤ 20 rpm to prevent premature rupture.
[0063] During paving and compaction, the layered paving thickness is ≤ 25 cm. Use a convex block vibrating roller (vibrating force ≥ 350 kN) and roll in the order of "static pressure 1 time → weak vibration 2 times → strong vibration 4 - 6 times". For capsule rupture control: when the monitored vibration acceleration reaches 4 - 6 g, the capsule starts to rupture and release water.
[0064] During the compaction process, while coal gangue or graded broken stone are extruded to generate supporting force, the water-containing capsule ball 15 is squeezed and broken, causing water to flow out. The water is mixed with cement and fly ash to form a gelling material, which wraps around the outside of coal gangue or graded broken stone and fills the voids, making the new roadbed rigid layer 4 form a whole, with better supporting effect and avoiding local settlement. Through the dynamic water release technology of the water-containing capsule ball, the "compaction - capsule rupture - gelling" integrated forming is realized.
[0065] Furthermore, through the design of the shell thickness gradient, the water-containing capsule balls 15 in the new roadbed rigid layer 4 have various thicknesses. The water-containing capsule balls 15 with smaller thickness are broken first, and the water-containing capsule balls 15 with thicker wall thickness have not been broken yet. During the road use process, as the use load continuously acts on the roadbed, the water-containing capsule balls 15 with thicker wall thickness inside the new roadbed rigid layer 4 are also squeezed and broken, and after being mixed and hardened with the cement and water that have not participated in the gelling reaction, they generate strength, which can delay the roadbed settlement and thus avoid the differential settlement between the new and old roadbeds.
[0066] A construction method for a structure for preventing differential settlement between new and old roadbeds during road expansion, which is used for manufacturing the above-mentioned structure for preventing differential settlement between new and old roadbeds during road expansion, includes the following steps:
[0067] Dig out a stepped structure on one side of the original roadbed 2;
[0068] Lay the equalizing layer structure on the stepped horizontal plane;
[0069] Cover the rigid layer structure outside the equalizing layer structure, and use the fixing part to fix the rigid layer structure to the original roadbed 2;
[0070] Sequentially lay and compact the new roadbed bottom layer 9, cushion structure, lifting layer 5, new roadbed rigid layer 4 and new road surface 3 on the side of the rigid layer structure away from the original roadbed 2, and lay a slope protection soil covering layer 10 on one side of the formed new roadbed.
[0071] When in use, since the original roadbed 2 is denser and has a higher bearing capacity compared to the new roadbed, by setting the stepped structure, it has a better supporting relationship with the new roadbed to prevent the new roadbed from slipping relative to the original roadbed 2. At the same time, in order to avoid uneven stress in the new roadbed causing damage to the original roadbed 2, by setting the equalizing layer structure, the force transmitted downward by the new road surface 3 is evenly distributed and then acts on the original roadbed 2 to avoid stress concentration. At the same time, the stepped concrete covering layer 11 and the steel bars 13 form a stable protection structure for the edge of the original roadbed 2 and are fixed by the anchor bolts 14. The lateral earth pressure and vertical load generated by the new roadbed first act on the stepped concrete covering layer 11 and then are transmitted to the original roadbed 2, effectively protecting the original roadbed 2 from being damaged. The new roadbed rigid layer 4 provided below the new road surface 3 improves the bearing capacity to avoid settlement of the new road surface 3 and prevent cracks from occurring at the joint between the original road surface 1 and the new road surface 3 due to settlement of the new road surface 3.
[0072] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.
[0073] The above embodiments are only descriptions of the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention should fall within the protection scope determined by the claims of the present invention.
Claims
1. A structure for preventing differential settlement of new and old roadbeds of an expanded road, characterized in that: include: A stepped structure is provided on one side of the original roadbed (2), the stepped structure having a plurality of stepped horizontal surfaces and stepped vertical surfaces, and the stepped structure is used to connect with the new roadbed; A uniform layer structure is laid on the stepped horizontal surface; A rigid layer structure is laid on the outside of the plurality of force-averaging layer structures and the plurality of stepped vertical surfaces, the rigid layer structure is stepped, the rigid layer structure is fixedly connected to the original roadbed (2) via a fixing portion, and the new roadbed is laid on a side of the rigid layer structure away from the original roadbed (2); The new roadbed comprises a new roadbed base layer (9), a cushion structure, a lifting layer (5), a new roadbed rigid layer (4) and a new road surface (3) which are arranged in sequence from bottom to top. The top surface of the new road surface (3) is at the same horizontal height as the top surface of the original road surface (1). The new road surface (3) is spliced with the original road surface (1). A slope protection covering layer (10) is laid on one side of the new roadbed.
2. A structure for preventing differential settlement of new and old roadbeds of an expanded road according to claim 1, characterized in that: The force-averaging layer structure comprises: A gangue bearing layer (12), the gangue bearing layer (12) being laid on the stepped horizontal plane.
3. The structure for preventing differential settlement of new and old roadbeds of an expanded road according to claim 2 is characterized by: The gangue bearing layer (12) is formed by compacting a mixture of gangue and fly ash.
4. A structure for preventing differential settlement of new and old roadbeds of an expanded road according to claim 3, characterized in that: In terms of mass fraction, the raw materials of the gangue pressure-bearing layer (12) include: 70-85 parts of coal gangue, 10-20 parts of fly ash, 5-10 parts of lime, and 0-5 parts of natural soil.
5. The structure for preventing differential settlement of new and old roadbeds of an expanded road according to claim 1 is characterized in that: The rigid layer structure is a stepped concrete covering layer (11), and a plurality of parallelly arranged steel bars (13) are embedded in the stepped concrete covering layer (11).
6. The structure for preventing differential settlement of new and old roadbeds of an expanded road according to claim 5, characterized in that: The fixing part comprises a plurality of anchor rods (14), one end of each anchor rod (14) passes through the vertical section of the corresponding stepped concrete covering layer (11) and the vertical surface of the step, and is then inserted into the original roadbed (2), and the anchor rod (14) is fixedly connected to the stepped concrete covering layer (11).
7. The structure for preventing differential settlement of new and old roadbeds of an expanded road according to claim 1, characterized in that: The cushion structure comprises a second waterproof layer (8), a graded coal gangue layer (7) and a first waterproof layer (6) which are arranged in sequence from bottom to top, and the second waterproof layer (8) is laid on the top surface of the new roadbed layer (9).
8. The structure for preventing differential settlement of new and old roadbeds of an expanded road according to claim 1, characterized in that: The lifting layer (5) is a mixture of graded crushed stone, coal gangue and fly ash.
9. The structure for preventing differential settlement of new and old roadbeds of an expanded road according to claim 1, characterized in that: The raw materials of the new roadbed rigid layer (4) include, by mass: 70-80 parts of coal gangue, 10-20 parts of sand, 5-8 parts of cement, 3-5 parts of fly ash, 2-4 parts of lime, and 5-10 parts of water.
10. A construction method for preventing differential settlement of new and old roadbeds of an expanded road, used for making a structure for preventing differential settlement of new and old roadbeds of an expanded road as claimed in any one of claims 1 to 9, characterized in that: The steps include: Excavating the stepped structure on one side of the original roadbed (2); Laying the force-averaging layer structure on the stepped horizontal surface; Covering the rigid layer structure outside the force-balancing layer structure, and using the fixing part to fix the rigid layer structure to the original roadbed (2); The new roadbed base layer (9), the cushion layer structure, the lifting layer (5), the new roadbed rigid layer (4) and the new road surface (3) are laid and compacted in sequence on the side of the rigid layer structure away from the original roadbed (2), and a slope protection covering layer (10) is laid on one side of the formed new roadbed.