An end splicing method for continuously reinforced concrete pavement and asphalt pavement paved on old road

Abstract

The present invention discloses an end splicing method for an old road overlaid with continuously reinforced concrete pavement and asphalt pavement, comprising: Step S1: determining the pavement length of the transition section; Step S2: treating the old cement concrete pavement of the transition section; Step S3: constructing the transition section; the continuously reinforced concrete slab of the continuously reinforced concrete pavement is gradually thickened in the transition section so that the elevation of the continuously reinforced concrete slab at the joint is the same as that of the cement stabilized base layer of the asphalt pavement; the continuously reinforced mesh laid in the transition section keeps the distance from the top of the continuously reinforced concrete slab unchanged; a transverse expansion joint is provided at the joint between the continuously reinforced concrete slab and the cement stabilized base layer in the transition section, and a longitudinal construction joint is provided during the construction of the subgrade division; Step S4: the surface functional layer of the continuously reinforced concrete pavement extends a certain length beyond the joint of the transition section and is connected to the asphalt surface layer of the asphalt pavement section. The present invention has the advantages of simple principle, easy construction, low cost, short construction period, good environmental protection, etc.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of road engineering, and particularly refers to a method for splicing the ends of a continuously reinforced concrete pavement and an asphalt pavement paved on an old road. Background Art

[0002] In the field of pavement facilities in modern construction projects, there are a certain number of cement concrete pavements. With the rapid development of regional economy, the traffic volume is also increasing rapidly, the traffic flow and overweight vehicles are gradually increasing, and coupled with the erosion of natural disasters such as rain and floods, road diseases continue to occur. The pavement structure of traditional cement concrete pavements is severely damaged, and the service performance of some sections has dropped significantly, thus affecting vehicle driving. Therefore, it is necessary to repair and transform the old cement pavement.

[0003] Through the investigation and analysis of the above traditional cement concrete pavement (the original old cement concrete pavement), it can be seen that the deflection detection of the original old cement concrete pavement slabs in the vast majority of sections is small, indicating that the overall structure strength of the old road is still acceptable and has utilization value. If the pavement is completely re-laid, it will require a high cost, and the entire construction period is relatively long, and the road closure time is long, which directly affects the traffic smoothness of the surrounding area. Furthermore, there will be a certain environmental protection impact on the construction site and its surrounding areas during the entire construction process.

[0004] The existing renovation schemes for old cement pavements mainly include:

[0005] 1) Treating the diseases of the original old cement pavement or performing rubblization and then paving an asphalt concrete pavement (changing white to black);

[0006] 2) Treating the original old road and then paving a cement concrete pavement or a continuously reinforced concrete pavement (white plus white).

[0007] However, in the application of traditional technologies in the reconstruction and expansion projects of old roads, there are generally engineering problems in the connection between the ends of CRCP and the ends of asphalt concrete pavements. Usually, the designed thickness of the asphalt pavement is greater than the thickness of the continuously reinforced concrete pavement. Improper splicing of the ends of CRCP and the asphalt pavement will cause diseases such as "jumping vehicles", pavement cracks, and pavement uneven settlement, thus affecting driving comfort and driving safety. There is no treatment method for the overlap of the two pavement structures when simultaneously paving a continuously reinforced concrete pavement and an asphalt pavement on an old cement pavement in the existing specifications and related researches. Summary of the Invention

[0008] The technical problem to be solved by the present invention lies in: aiming at the technical problems existing in the prior art, the present invention provides a method for splicing the ends of a continuously reinforced concrete pavement and an asphalt pavement paved on an old road, which has a simple principle, is easy to construct, has a low cost, a short construction period, and good environmental protection.

[0009] To solve the above technical problems, the present invention adopts the following technical solutions:

[0010] A method for end splicing of an old road overlaid with continuously reinforced concrete pavement and asphalt pavement, the process of which includes:

[0011] Step S1: Determine the pavement length of the transition section; determine the pavement length of the transition section according to the design thickness of the continuously reinforced concrete pavement and the asphalt pavement, the longitudinal slope of the old road at the connection of the continuously reinforced concrete pavement and the asphalt pavement, and the maximum allowable longitudinal slope of this section;

[0012] Step S2: Treat the old cement concrete pavement slab in the transition section;

[0013] Step S3: Construction of the transition section; the continuously reinforced concrete slab of the continuously reinforced concrete pavement is gradually thickened in the transition section so that the elevation of the continuously reinforced concrete slab at the joint is the same as that of the cement stabilized base layer of the asphalt pavement; the continuously reinforced steel mesh laid in the transition section keeps the distance from the top of the continuously reinforced concrete slab unchanged, and the reinforcement ratio in the transition section is the same as that in the CRCP section; a transverse expansion joint is set at the joint between the continuously reinforced concrete slab and the cement stabilized base layer in the transition section, and a longitudinal construction joint is set when constructing in sections;

[0014] Step S4: The surface functional layer of the continuously reinforced concrete pavement crosses a certain length at the joint of the transition section and is connected to the asphalt surface layer of the asphalt pavement section; the thickness of the surface functional layer on the CRC slab in the transition section gradually increases, and through the change in the transition section, the elevation of the surface functional layer at the joint is the same as that of the upper surface layer of the asphalt pavement.

[0015] As a further improvement of the method of the present invention: in the step S1, the pavement structure of the transition section adopts a continuously reinforced concrete pavement structure with variable thickness extension.

[0016] As a further improvement of the method of the present invention: in the step S2, the old cement concrete slabs in the transition section are generally retained, and the old cement pavement near the end of the asphalt pavement at a certain distance and the old cement concrete slabs under the entire asphalt pavement are crushed; the stress absorption layer of the continuously reinforced concrete pavement is adjusted to the same elevation as the leveling layer of the asphalt pavement through the transition section, and the joint between the two requires smoothness and naturalness.

[0017] As a further improvement of the method of the present invention: in the step S3, a joint filler board is arranged in the transverse expansion joint, and an anti-cracking sticker is pasted on the top of the transverse expansion joint.

[0018] As a further improvement of the method of the present invention: in the step S4, the ends of the broken old road slabs, the ends of the cement stabilized base course, and the ends of the lower surface layer of the asphalt pavement are staggered by a certain distance to form a step as a transition, so as to control that the joints of each structural layer are not in the same cross-section.

[0019] As a further improvement of the method of the present invention: The process of step S1 includes:

[0020] Step S101: Obtain the allowable maximum longitudinal slope value; determine the allowable maximum longitudinal slope value i1 according to the designed speed v of this section of the road.

[0021] Step S102: Obtain the shortest length L of the transition section pavement. min ; Calculate the shortest length L of the transition section according to the longitudinal slope i2 of the old road in the transition section and the elevation difference △H between the end of the continuously reinforced concrete pavement and the end of the asphalt pavement. min :

[0022] i = i1 ± i2

[0023]

[0024] Wherein, when it is an uphill section from the end of the continuously reinforced concrete pavement to the end of the asphalt pavement, take the "-" sign; when it is a downhill section, take the "+" sign.

[0025] Step S103: The length L of the transition section is required to be not less than the calculated shortest length L of the transition section. min ;

[0026] Step S104: The pavement structure of the transition section refers to that of the continuously reinforced concrete pavement section, and adopts a continuously reinforced concrete pavement structure with variable thickness extension.

[0027] As a further improvement of the method of the present invention: In step S2, the treatment of the old cement concrete slab satisfies:

[0028] a) Generally retain the old cement concrete slabs in the transition section, but crush the old cement pavement within a certain distance from the end of the asphalt pavement and the old cement concrete slabs under the entire asphalt pavement.

[0029] b) When paving a continuously reinforced concrete surface layer on the old road, set a layer of crack-resistant leveling layer. The crack-resistant leveling layer of the continuously reinforced concrete pavement is adjusted through the transition section to the same elevation as the bottom of the water-stable base layer of the asphalt pavement, and the joint between the two is required to be smooth and natural.

[0030] As a further improvement of the method of the present invention: The process of step S3 includes:

[0031] Step S301: Lay a continuously reinforced concrete slab in the transition section with the same reinforcement ratio as that in the CRCP section.

[0032] Step S302: Keep the distance between the continuously reinforced steel mesh laid in the transition section and the top of the continuously reinforced concrete slab unchanged, and the continuously reinforced concrete slab gradually thickens in the transition section so that the elevation of the continuously reinforced concrete slab at the joint is the same as that of the water-stable layer of the asphalt pavement.

[0033] Step S303: Transverse expansion joints are provided at the joints between the continuously reinforced concrete slab in the transition section and the cement stabilized base course.

[0034] Step S304: The setting of the longitudinal construction joints is consistent with the construction of the continuously reinforced concrete pavement.

[0035] As a further improvement of the method of the present invention: The process of step S4 includes:

[0036] Step S401: The surface functional layer of the continuously reinforced concrete pavement extends a certain length beyond the transition section joint and is connected to the asphalt surface layer of the asphalt pavement section.

[0037] Step S402: According to the designed elevation of the asphalt pavement, the thickness of the surface functional layer on the CRC slab in the transition section gradually increases. Through the change in the transition section, the elevation of the surface functional layer at the joint is the same as that of the upper surface layer of the asphalt pavement.

[0038] Step S403: The side connection between the upper asphalt layer and the lower asphalt layer of the asphalt pavement should be well bonded, and the ends of the broken old road slabs, the ends of the cement stabilized base course, and the ends of the lower asphalt layer of the asphalt pavement are staggered by a certain distance to form a step as a transition, controlling that the connection parts of each structural layer are not in the same cross-section.

[0039] Compared with the prior art, the advantages of the present invention are as follows:

[0040] 1. The method for splicing the ends of the old road overlaid with continuously reinforced concrete pavement and asphalt pavement of the present invention has a simple principle, easy construction, low cost, short construction period, and good environmental protection. It solves the engineering problem that when reconstructing the old cement concrete pavement, the ends of the broken old road slabs, the ends of the cement stabilized base course, and the ends of the lower asphalt layer of the asphalt pavement are staggered by a certain distance to form a step as a transition, controlling that the connection parts of each structural layer are not in the same cross-section, and the elevation of the two pavement structures of the stepped continuously reinforced concrete pavement and the asphalt pavement is inconsistent.

[0041] 2. The method for splicing the ends of the old road overlaid with continuously reinforced concrete pavement and asphalt pavement of the present invention lays the same steel mesh in the transition section according to the requirements of the continuously reinforced concrete pavement section. The continuously reinforced concrete pavement and the continuously reinforced concrete slab in the transition section are integrally cast, making the connection at the end of the pavement more firm. The structural parameters of the pavement structure in the transition section refer to the structural design parameters of the continuously reinforced concrete pavement section, and the two are constructed integrally, reducing the construction difficulty and construction cost.

[0042] 3. The method for splicing the ends of the old road overlaid with continuously reinforced concrete pavement and asphalt pavement of the present invention staggers the ends of the broken old road slabs, the ends of the cement stabilized base course, and the ends of the lower asphalt layer of the asphalt pavement by a certain distance to form a step as a rigid transition, controlling that the connection parts of each structural layer are not in the same cross-section, which can make the two pavement structures better combined and further slow down the generation of pavement uneven settlement at the joint. Brief Description of the Drawings

[0043] Figure 1 It is a schematic flow chart of the method of the present invention in a specific application example.

[0044] Figure 2 It is a schematic structural principle diagram of paving continuously reinforced concrete pavement on an old cement pavement in a specific application example of the present invention.

[0045] Figure 3 It is a schematic structural principle diagram of paving asphalt pavement on an old cement pavement in a specific application example of the present invention.

[0046] Figure 4 It is a schematic structural principle diagram of the pavement in the transition section in a specific application example of the present invention.

[0047] Figure 5 It is a schematic structural principle diagram of the lapping treatment in a specific application example of the present invention.

[0048] Figure 6 is Figure 5 a partial enlarged schematic structural principle diagram of

[0049] Legend Explanation:

[0050] 1. Longitudinal steel bars; 2. Transverse steel bars; 3. AC-13 fine-grained modified asphalt concrete surface course; 4. SBS modified asphalt synchronous crushed stone seal coat; 5. Continuously reinforced concrete slab; 6. AC-10 fine-grained asphalt concrete bottom layer; 7. Original cement concrete pavement; 8. AC-13 fine-grained modified asphalt concrete surface course; 9. AC-20 medium-grained asphalt concrete bottom layer; 10. SBS modified asphalt synchronous crushed stone seal coat; 11. Cement stabilized crushed stone upper base course; 12. Cement stabilized crushed stone lower base course; 13. Graded crushed stone leveling course; 14. Original cement concrete pavement; 15. Crack resistant tape; 16. Joint filler board; 17. Transition section. Detailed Description of the Preferred Embodiments

[0051] The present invention will be further described in detail below with reference to the accompanying drawings of the specification and specific embodiments.

[0052] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "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 application and simplifying the description, 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 thus should not be construed as a limitation to the present application.

[0053] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality of" means two or more unless otherwise specifically defined.

[0054] In this application, unless otherwise clearly stipulated and defined, terms such as "assemble", "be connected with", "connect", "fix", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0055] As Figures 1 - 6 shown, a method for end splicing of an old road overlaid with continuously reinforced concrete pavement and asphalt pavement according to the present invention includes the following steps:

[0056] Step S1: Determine the pavement length of the transition section;

[0057] Determine the pavement length of the transition section according to the design thickness of the continuously reinforced concrete pavement and the asphalt pavement, the longitudinal slope of the old road at the connection of the continuously reinforced concrete pavement and the asphalt pavement, and the maximum allowable longitudinal slope of this section.

[0058] The pavement structure of the transition section adopts a continuously reinforced concrete pavement structure with variable thickness extension.

[0059] Step S2: Treat the old cement concrete pavement slab in the transition section;

[0060] The old cement concrete slabs in the transition section are generally retained, but the old cement pavement at a certain distance from the end of the asphalt pavement in the transition section and the old cement concrete slabs under the entire asphalt pavement are crushed.

[0061] The stress absorption layer of the continuously reinforced concrete pavement is adjusted to the same elevation as the leveling layer of the asphalt pavement through the transition section, and the joint between the two requires smoothness, naturalness, and good bonding.

[0062] Step S3: Construction of the transition section;

[0063] The continuously reinforced concrete slab 5 of the continuously reinforced concrete pavement gradually thickens in the transition section to make the elevation of the continuously reinforced concrete slab 5 at the joint the same as that of the water-stable layer of the asphalt pavement.

[0064] The continuously reinforced mesh laid in the transition section remains at a constant distance from the top of the continuously reinforced concrete slab 5, and the reinforcement ratio in the transition section is the same as that in the CRCP section;

[0065] At the joint between the continuously reinforced concrete slab 5 and the cement stabilized base layer in the transition section, a transverse expansion joint with an appropriate width is set. A joint filler board is set in the joint, and a polymer anti-cracking sticker is pasted on the top of the expansion joint; When constructing in sections, longitudinal construction joints are set;

[0066] Step S4: The surface functional layer of the continuously reinforced concrete pavement should extend beyond the joint of the transition section by a certain length and connect with the asphalt surface layer of the asphalt pavement section.

[0067] The thickness of the surface functional layer on the CRC slab in the transition section should gradually increase. Through the change in the transition section, the elevation of the surface functional layer at the joint is the same as that of the upper surface layer of the asphalt pavement.

[0068] The ends of the broken old road slabs, the ends of the cement stabilized base layer, and the ends of the lower asphalt pavement layer are staggered by a certain distance to form steps for transition, so as to control that the joints of each structural layer are not on the same cross-section.

[0069] In a specific application example, according to the actual application needs, the process of step S1 may include:

[0070] Step S101: Obtain the allowable maximum longitudinal slope value;

[0071] According to the current specification "Technical Standard for Highway Engineering" (JTG B01 - 2014), based on the designed speed v of this section, determine the allowable maximum longitudinal slope value i1;

[0072] Step S102: Obtain the shortest length L of the transition section pavement min ;

[0073] According to the longitudinal slope i2 of the old road in the transition section and the elevation difference △H between the end of the continuously reinforced concrete pavement and the end of the asphalt pavement, calculate the shortest length L of the transition section min .

[0074] i = i1 ± i2

[0075]

[0076] Among them, when it is an uphill section from the end of the continuously reinforced concrete pavement to the end of the asphalt pavement, take the "-" sign, and when it is a downhill section, take the "+" sign;

[0077] Step S103: The length L of the transition section is required to be not less than the calculated shortest length L of the transition section min ;

[0078] Step S104: The pavement structure of the transition section refers to the continuously reinforced concrete pavement section and adopts a continuously reinforced concrete pavement structure with variable thickness extension.

[0079] In a specific application example, according to the actual application needs, in step S2, the treatment of the old cement concrete slab should meet the following requirements:

[0080] a) Generally, the old cement concrete slabs in the transition section are retained, but the old cement pavement with a length of 0.3 m near the end of the asphalt pavement and the old cement concrete slabs under the entire asphalt pavement are crushed.

[0081] b) When a continuously reinforced concrete surface layer is paved on the old road, an anti-cracking leveling layer needs to be set. The anti-cracking leveling layer of the continuously reinforced concrete pavement is adjusted through the transition section to the same elevation as the bottom of the cement stabilized base of the asphalt pavement. The joint between the two requires smoothness, naturalness, and good bonding.

[0082] In a specific application example, according to the actual application needs, the detailed process of step S3 can include:

[0083] Step S301: Adopt the same reinforcement ratio as the CRCP section and pave a continuously reinforced concrete slab 5 in the transition section;

[0084] Step S302: Keep the distance between the continuously reinforced steel mesh laid in the transition section and the top of the continuously reinforced concrete slab 5 unchanged. The continuously reinforced concrete slab 5 gradually thickens in the transition section so that the elevation of the continuously reinforced concrete slab 5 at the joint is the same as that of the cement stabilized layer of the asphalt pavement;

[0085] Step S303: Set a transverse expansion joint with an appropriate width at the joint between the continuously reinforced concrete slab 5 and the cement stabilized layer in the transition section. For example, the width of the expansion joint can be taken as 2 cm according to actual needs; the filling board material at the expansion joint is a rubber foam board; paste a polymer anti-cracking sticker at the top of the expansion joint, the thickness of the anti-cracking sticker is 2 mm, and the width is 30 cm with the expansion joint as the center line;

[0086] Step S304: The setting of the longitudinal construction joint is consistent with the construction of the continuously reinforced concrete pavement.

[0087] In a specific application example, according to the actual application needs, the detailed process of step S4 can include:

[0088] Step S401: The surface functional layer of the continuously reinforced concrete pavement should extend beyond the transition section joint by a certain length and connect with the asphalt surface layer of the asphalt pavement section;

[0089] Step S402: According to the designed elevation of the asphalt pavement, the thickness of the surface functional layer on the CRC slab in the transition section should gradually increase. Through the change in the transition section, the surface functional layer at the joint is the same elevation as the upper surface layer of the asphalt pavement;

[0090] Step S403: The side joints between the asphalt surface course and the lower asphalt pavement layer should be well bonded. The ends of the broken old road slabs, the ends of the cement stabilized base course, and the ends of the lower asphalt pavement layer should be staggered by a certain distance to form steps as a transition, so as to control that the joints of each structural layer are not on the same cross-section.

[0091] The following will further illustrate the present invention with a specific application example.

[0092] In this embodiment, the specific calculation parameters of the structure of the continuously reinforced concrete pavement and the asphalt pavement overlaid on the old cement concrete pavement are as follows: Design speed: 60 km / h (40 km / h in the town section), road width 10.5 m, structure form of the continuously reinforced concrete pavement overlaid on the old cement pavement: 30 cm thick C35 cement concrete pavement 7 + 3 cm thick AC-10 fine-grained asphalt concrete lower layer 6 (A-70#) + 18 cm thick continuously reinforced concrete slab 5 + 1 cm thick SBS modified asphalt synchronous crushed stone seal coat 4 + 5 cm thick AC-13 fine-grained modified asphalt concrete surface layer 3;

[0093] Structure form of the asphalt pavement overlaid on the old cement pavement: 30 cm thick crushed old cement concrete pavement 14 + 5 cm thick graded crushed stone leveling layer 13 + 17 cm thick 5% cement stabilized sub-base 12 + 17 cm thick 5% cement stabilized upper base 11 + 1 cm thick SBS modified asphalt synchronous crushed stone seal coat 10 + 5 cm thick AC-20 medium-grained asphalt concrete lower layer 9 (A-70#) + 4 cm thick AC-13 fine-grained modified asphalt concrete surface layer 8. The elevation of the asphalt pavement is 22 cm higher than that of the continuously reinforced concrete pavement. Improper treatment will affect driving comfort and driving safety. The detailed steps of the lap treatment method for the continuously reinforced concrete pavement and the asphalt pavement overlaid on the old cement pavement in this embodiment are as follows:

[0094] Step S1000: According to the original design document of this section, the design speed v of this section is 40 km / h, and the allowable maximum longitudinal slope i1 = 7% is determined;

[0095] Step S2000: According to the on-site measurement data, the longitudinal slope i2 of the old road in the transition section 17 is 0.5%. According to the overhaul design document, the elevation difference △H between the end of the continuously reinforced concrete pavement and the end of the asphalt pavement is 22 cm, and the shortest length L of the transition section 17 is calculated min .

[0096] i = i1 ± i2

[0097]

[0098] Among them, when it is a downhill section from the end of the continuously reinforced concrete pavement to the end of the asphalt pavement, the "+" sign is taken;

[0099] After calculation, L is obtained min = 293.3 cm, and the length L of the transition section 17 is taken as 300 cm;

[0100] Step S3000: Process the old cement concrete pavement slabs in the transition section. The old cement concrete slabs in the transition section are generally retained, but the old cement pavement with a length of 30 cm near the end of the asphalt pavement and the old cement concrete slabs under the entire asphalt pavement are crushed.

[0101] Step S4000: Determine the design parameters of each structural layer of the transition section pavement, and lay the corresponding structural layers according to the design drawing of the transition section pavement structure. The transition section pavement structure is as Figure 3 shown.

[0102] Step S5000: The stress absorption layer (the AC-10 fine-grained asphalt concrete lower layer 6) of the continuously reinforced concrete pavement is adjusted from 3 cm thick in the transition section to 5 cm thick, so that it has the same elevation as the leveling layer of the asphalt pavement. The joint between the two requires smoothness, naturalness and good bonding;

[0103] Step S6000: Lay the continuously reinforced concrete slab 5 on the stress absorption layer (the AC-10 fine-grained asphalt concrete lower layer 6). The continuously reinforced concrete slab 5 of the continuously reinforced concrete pavement is gradually thickened in the transition section, adjusted from 20 cm thick in the transition section to 34 cm thick, so that the continuously reinforced concrete slab 5 at the joint has the same elevation as the water-stable layer (the cement stabilized macadam upper base course 11) of the asphalt pavement. The steel mesh of the continuously reinforced concrete slab 5 keeps the distance from the top of the slab unchanged. The spacing, diameter and steel grade of the transverse steel bars 2 and longitudinal steel bars 1 all adopt the same reinforcement design parameters as those in the continuously reinforced concrete section. Specifically, it can be: φ16@18.5 longitudinal steel bars 1, φ12@62 transverse steel bars 2;

[0104] Step S7000: Set a transverse expansion joint with an appropriate width at the joint between the continuously reinforced concrete slab 5 and the water-stable layer (the cement stabilized macadam upper base courses 11, 12) in the transition section. The width of the expansion joint is taken as 2 cm, and the material of the joint filler board at the expansion joint is rubber foam board; Paste a crack-resistant sticker 15 at the top of the expansion joint. The crack-resistant sticker 15 can be made of polymer material, and the thickness of the crack-resistant sticker 15 is 2 mm. Taking the expansion joint as the center line, the width is 30 cm;

[0105] Step S8000: Set longitudinal construction joints, and the setting of the longitudinal construction joints is consistent with the construction of the continuously reinforced concrete section pavement. Specifically, extend the transverse steel bars 2 in the transition section by 60 cm as transverse tie bars and carry out chiseling treatment on the side.

[0106] Step S9000: The transition section is overlaid with an SBS modified asphalt synchronous chip seal layer 4 and a fine-grained modified asphalt concrete surface course 3 as the surface functional layer. The thickness of the SBS modified asphalt synchronous chip seal layer 4 remains unchanged at 1 cm, and the thickness of the fine-grained modified asphalt concrete surface course 3 gradually increases from 5 cm to 9 cm. Through the transition section change, the surface functional layer (SBS modified asphalt synchronous chip seal layer 4 + fine-grained modified asphalt concrete surface course 3) at the joint is made to have the same elevation as the surface course of the asphalt pavement (AC-20 medium-grained asphalt concrete lower layer 9 (A-70#) + 4 cm thick AC-13 fine-grained modified asphalt concrete surface course 8). The surface functional layer of the continuously reinforced concrete pavement should extend 30 cm beyond the transition section joint and connect with the asphalt surface course of the asphalt pavement section.

[0107] Step S1100: The ends of the asphalt surface course and the lower layer of the asphalt pavement should be well bonded to the connections of each structural layer in the transition section. Moreover, the ends of the broken old road slabs, the ends of the cement stabilized base course, and the ends of the lower layer of the asphalt pavement are staggered by a certain distance to form steps as a transition, controlling that the connecting parts of each structural layer are not on the same cross-section.

[0108] The above are only the preferred embodiments of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions falling within the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for those of ordinary skill in the art in this technical field, several improvements and refinements made without departing from the principle of the present invention should be regarded as within the protection scope of the present invention.

Claims

1. A method for splicing the end of a continuously reinforced concrete pavement and an asphalt pavement paved on an old road, characterized in that, The process includes: Step S1: Determine the pavement length of the transition section; determine the pavement length of the transition section according to the design thickness of the continuously reinforced concrete pavement and the asphalt pavement, the longitudinal slope of the old road at the connection between the continuously reinforced concrete pavement and the asphalt pavement, and the maximum allowable longitudinal slope of the section. Step S2: Treat the old cement concrete pavement in the transition section. Step S3: Construction of the transition section; the continuously reinforced concrete slab of the continuously reinforced concrete pavement is gradually thickened in the transition section so that the elevation of the continuously reinforced concrete slab at the joint is the same as that of the cement stabilized base layer of the asphalt pavement; the continuously reinforced mesh laid in the transition section keeps the distance from the top of the continuously reinforced concrete slab unchanged, and the reinforcement ratio in the transition section is the same as that in the CRCP section; a transverse expansion joint is set at the joint between the continuously reinforced concrete slab and the cement stabilized base layer in the transition section, and a longitudinal construction joint is set when constructing in sections. Step S4: The surface functional layer of the continuously reinforced concrete pavement extends beyond the joint of the transition section by a certain length and is connected to the asphalt surface layer of the asphalt pavement section; the thickness of the surface functional layer on the CRC slab in the transition section gradually increases and changes through the transition section so that the elevation of the surface functional layer at the joint is the same as that of the upper surface layer of the asphalt pavement.

2. The method for end splicing of an old road overlaid with a continuously reinforced concrete pavement and an asphalt pavement according to claim 1, characterized in that, In the step S1, the pavement structure of the transition section adopts a continuously reinforced concrete pavement structure with variable thickness extension.

3. The method for end splicing of continuously reinforced concrete pavement and asphalt pavement paved on the old road according to claim 1, characterized in that, In the step S2, the old cement concrete slabs in the transition section are generally retained, and the old cement pavement at a certain distance from the end of the transition section near the asphalt pavement and the old cement concrete slabs under the entire asphalt pavement are crushed. The stress absorption layer of the continuously reinforced concrete pavement is adjusted through the transition section to the same elevation as the leveling layer of the asphalt pavement, and the joint between the two requires smoothness and naturalness.

4. The method for end splicing of continuously reinforced concrete pavement and asphalt pavement overlaid on old road according to claim 1, characterized in that, In the step S3, a joint filler board is set in the transverse expansion joint, and an anti-cracking sticker is pasted on the top of the transverse expansion joint.

5. The method for end splicing of an old road overlaid with a continuously reinforced concrete pavement and an asphalt pavement according to claim 1, characterized in that, In the step S4, the ends of the broken old road slabs, the ends of the cement stabilized base layer, and the ends of the lower surface layer of the asphalt pavement are staggered by a certain distance to form a step as a transition, and the connection parts of each structural layer are controlled not to be on the same cross-section.

6. The method for end splicing of continuously reinforced concrete pavement and asphalt pavement paved on old road according to any one of claims 1-5, characterized in that, The process of the step S1 includes: Step S101: Obtain the maximum allowable longitudinal slope value; determine the maximum allowable longitudinal slope value i1 according to the designed speed v of this section. Step S102: Obtain the shortest length of the transition section pavement L min ; Calculate the shortest length of the transition section according to the longitudinal slope i2 of the old road in the transition section and the elevation difference △H between the end of the continuously reinforced concrete pavement and the end of the asphalt pavement L min : Among them, when it is an uphill section from the end of the continuously reinforced concrete pavement to the end of the asphalt pavement, take the "-" sign, and when it is a downhill section, take the "+" sign. Step S103: The required length L of the transition section shall not be less than the calculated shortest length L of the transition section min ; Step S104: The pavement structure of the transition section refers to the continuously reinforced concrete pavement section and adopts a continuously reinforced concrete pavement structure with variable thickness extension.

7. The method for end splicing of continuously reinforced concrete pavement and asphalt pavement on the old road as claimed in claim 3, characterized in that, In the step S2, the treatment of the old cement concrete slabs satisfies: a) The old cement concrete slabs in the transition section are generally retained, but the old cement pavement at a certain distance from the end of the transition section near the asphalt pavement and the old cement concrete slabs under the entire asphalt pavement are crushed. b) When a continuously reinforced concrete surface layer is paved on the old road, a layer of anti-cracking leveling layer is set. The anti-cracking leveling layer of the continuously reinforced concrete pavement is adjusted through the transition section to the same elevation as the bottom of the cement stabilized base layer of the asphalt pavement, and the joint between the two requires smoothness and naturalness.

8. The method for end splicing of the continuous reinforced concrete pavement and the asphalt pavement paved on the old road according to any one of claims 1-5, characterized in that, The process of the step S3 includes: Step S301: Adopt the same reinforcement ratio as in the CRCP section and lay a continuously reinforced concrete slab in the transition section. Step S302: Keep the distance between the continuously reinforced mesh laid in the transition section and the top of the continuously reinforced concrete slab unchanged, and gradually thicken the continuously reinforced concrete slab in the transition section so that the elevation of the continuously reinforced concrete slab at the joint is the same as that of the cement stabilized base layer of the asphalt pavement; Step S303: Set a transverse expansion joint at the joint between the continuously reinforced concrete slab and the cement stabilized base layer in the transition section; Step S304: The setting of the longitudinal construction joint is consistent with the construction of the continuously reinforced concrete pavement.

9. The method for end splicing of continuously reinforced concrete pavement and asphalt pavement paved on old road according to any one of claims 1-5, characterized in that, The process of the said Step S4 includes: Step S401: The surface functional layer of the continuously reinforced concrete pavement extends a certain length beyond the joint of the transition section and connects with the asphalt surface layer of the asphalt pavement section; Step S402: According to the designed elevation of the asphalt pavement, the thickness of the surface functional layer on the CRC slab in the transition section gradually increases. After changing through the transition section, make the elevation of the surface functional layer at the joint the same as that of the upper surface layer of the asphalt pavement; Step S403: The side connection between the asphalt upper surface layer and the lower surface layer of the asphalt pavement should be well bonded, and the ends of the broken old road slabs, the ends of the cement stabilized base layer, and the ends of the lower surface layer of the asphalt pavement are staggered by a certain distance to form a step as a transition, so as to control that the connecting parts of each structural layer are not on the same cross-section.

Images