Prestressed concrete surface layer structure of cross-shaped level crossing
By adopting a combined structure of prefabricated prestressed concrete surface layer and cast-in-place self-stressed surface layer at the cross-level intersection, the problem of road rutting at the cross-level intersection is solved, and the durability and bearing capacity of the road surface are improved.
Patent Information
- Application Number
- CN202422670165.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-04
- Publication Date
- 2025-07-11
- Estimated Expiration
- 2034-11-04
AI Technical Summary
On cross-level intersection sections, prestressed concrete structures are not easy to lay rims, resulting in frequent start-up and acceleration and deceleration of asphalt road vehicles, which poses safety hazards.
The combined structure of the prefabricated prestressed concrete surface layer and the cast-in-place self-stressed surface layer is adopted. The prefabricated prefabricated concrete surface layer is set at the non-intersection of the intersection, and the cast-in-place self-stressed surface layer is set at the intersection. The bidirectional self-stressed surface layer is formed through the bidirectional constraints of high-expanded concrete and self-stressed tendons, which bears the complex stress of the vehicle.
It effectively avoids the occurrence of asphalt pavement ruts, improves the durability of the cross-level road surface, prevents cracking of the end of the first-sliding plate, and enhances the load-bearing capacity of the pavement.
Smart Images
Figure CN223088213U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a concrete surface layer structure of a road, and more specifically, to a prestressed concrete surface layer structure at a cross intersection of a road. Background Art
[0002] With the rapid development of China's economy, there are more and more heavy-duty traffic. Correspondingly, there are also more and more assembled prestressed concrete pavements suitable for heavy-duty traffic and capable of standardized production. Compared with asphalt pavements, prestressed concrete pavements have stronger bearing capacity and are not prone to rutting. Especially in the flat intersection section, the effect of preventing rutting is more obvious. However, in the cross-section of the cross intersection section of the road, because it is a double-sided slope and the stress is complex, it is not easy to arrange steel bars in the prestressed concrete structure. Therefore, asphalt concrete pavements are still used at present. However, in the cross-section of the cross intersection section of the road, vehicles start, accelerate and decelerate frequently, resulting in easy rutting of the asphalt pavement, bringing potential safety hazards to traffic. For this reason, the utility model proposes a prestressed concrete surface layer structure at a cross intersection of a road, in which the cross-section and non-cross-section of the cross intersection are respectively provided with a cast-in-place self-stressing surface layer and a pretensioned slab. Summary of the Invention
[0003] The utility model aims to overcome the above-mentioned technical problems and provides a prestressed concrete surface layer structure at a cross intersection of a road.
[0004] The prestressed concrete surface layer structure at a cross intersection of the utility model includes an assembled prestressed concrete surface layer and a cast-in-place self-stressing surface layer. The assembled prestressed concrete surface layer is composed of pretensioned slabs evenly laid. Its characteristics are that: the cast-in-place self-stressing surface layer is arranged at the cross-section of the cross intersection, and the assembled prestressed concrete surface layer is arranged at the non-cross-section in four directions of the cross intersection; the assembled prestressed concrete surface layer at the non-cross-section of the cross intersection is composed of a left surface layer slab and a right surface layer slab. Both the left surface layer slab and the right surface layer slab include edge pretensioned slabs and inner pretensioned slabs. The edge pretensioned slabs and the inner pretensioned slabs are connected by a transverse self-stressing joint. A temperature joint is arranged between the left surface layer slab and the right surface layer slab; the cast-in-place self-stressing surface layer is composed of high-expansion concrete and self-stressing transverse steel bars and self-stressing longitudinal steel bars cast therein. Anchor bars welded to the self-stressing transverse steel bars and self-stressing longitudinal steel bars are anchored at the outer ends of the edge pretensioned slabs.
[0005] In the prestressed concrete surface layer structure at a cross intersection of the utility model, the pretensioned slab is composed of pretensioned slab concrete, steel strands and pretensioned slab transverse steel bars cast therein. The length direction of the steel strands is consistent with the driving direction of the road, and the pretensioned slab transverse steel bars are consistent with the width direction of the road.
[0006] The prestressed concrete surface layer structure of the cross intersection of the utility model, the transverse self-stress joint is composed of high-expansion concrete and self-stress joint longitudinal bars and self-stress joint transverse bars cast therein. The length direction of the self-stress joint longitudinal bars is consistent with the road width direction. The self-stress joint transverse bars are formed by welding the anchor bars respectively anchored at the ends of the inner pre-tensioned slab and the edge pre-tensioned slab.
[0007] The prestressed concrete surface layer structure of the cross intersection of the utility model, the width of the pre-tensioned slab is 3.50m - 3.75m, the length is 6.0m - 9.0m, the thickness is 20cm - 24cm, the grade of the pre-tensioned slab concrete is 40MPa - 45MPa, and the steel strands are arranged at a position 1cm - 2cm below the central axis of the cross section of the pre-tensioned slab.
[0008] The prestressed concrete surface layer structure of the cross intersection of the utility model, the width of the transverse self-stress joint is 20cm - 30cm, the height is 20cm - 24cm, the grade of the high-expansion concrete is 40MPa - 45MPa, and the longitudinal pressure value generated by the high-expansion concrete in the transverse self-stress joint is 4MPa - 5MPa.
[0009] The prestressed concrete surface layer structure of the cross intersection of the utility model, the temperature joint is formed by pouring and solidifying hot asphalt with a width of 2mm - 4mm and a height of 20cm - 24cm.
[0010] The prestressed concrete surface layer structure of the cross intersection of the utility model, the grade of the expansive concrete in the cast-in-place self-stress surface layer is 40MPa - 45MPa, and the self-stress values generated by the expansive concrete in the longitudinal direction and the transverse direction after pouring are 2MPa - 4MPa.
[0011] The beneficial effects of the utility model are as follows: The prestressed concrete surface layer structure of the cross intersection of the utility model is composed of a prefabricated prestressed concrete surface layer and a cast-in-place self-stress surface layer. The prefabricated prestressed concrete surface layer is arranged at the non-crossing part of the crossroads and is composed of uniformly laid road pre-tensioned slabs. The cast-in-place self-stress surface layer is arranged at the crossing part of the crossroads and is composed of expansive concrete and self-stress transverse bars and self-stress longitudinal bars cast therein. During construction, first, the pre-tensioned slabs constituting the prefabricated prestressed concrete surface layer are laid, which is equivalent to forming a limit for the cast-in-place self-stress surface layer at the crossing part of the crossroads. The expansive concrete in the cast-in-place self-stress surface layer is subjected to two-way constraints by the self-stress transverse bars and longitudinal bars to generate two-way self-stress, so that a prestressed concrete pavement structure is formed at the crossing part of the crossroads. The generated two-way self-stress can withstand the tensile stresses in all directions generated by the frequent starting and turning of vehicles on the road surface, eliminating the need to lay asphalt pavement and avoiding the occurrence of rutting phenomena easily occurring in asphalt pavements, thereby improving the durability of the pavement at the cross plane intersection.
[0012] Meanwhile, the inner pretensioned slabs and the edge pretensioned slabs in the left and right deck plates of the surface layer are connected by transverse self-stress joints. This not only realizes the firm connection of adjacent pretensioned slabs, enabling them to jointly bear the vehicle load, but also under the expansion effect of the expansive concrete in the transverse self-stress joints, the ends of the pretensioned slabs are compressed, effectively avoiding the occurrence of cracking at the ends of the pretensioned slabs. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 is a top view of the prestressed concrete surface layer structure of the crossroads of the present utility model;
[0014] Figure 2 is a cross-sectional view of the prestressed concrete surface layer structure of the crossroads of the present utility model.
[0015] In the figures: 1 inner pretensioned slab, 2 edge pretensioned slab, 3 transverse self-stress joint, 4 cast-in-place self-stress surface layer, 5 temperature joint, 6 self-stress transverse reinforcement, 7 self-stress longitudinal reinforcement, 8 expansive concrete, 9 steel strand, 10 transverse reinforcement of pretensioned slab, 11 concrete of pretensioned slab, 12 longitudinal reinforcement of self-stress joint, 13 transverse reinforcement of self-stress joint, 14 high-expansion concrete, 15 left deck plate of surface layer, 16 right deck plate of surface layer, 17 anchoring reinforcement. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0016] The present utility model will be further described below in conjunction with the drawings and embodiments.
[0017] As Figure 1 and Figure 2 shown, the top view and the cross-sectional view of the prestressed concrete surface layer structure of the crossroads of the present utility model are respectively given. The prestressed concrete surface layer structure of the crossroads shown is composed of a prefabricated prestressed concrete surface layer and a cast-in-place self-stress surface layer 4. The prefabricated prestressed concrete surface layer is composed of roadbed pretensioned slabs laid evenly. The cast-in-place self-stress surface layer 4 is arranged at the intersection part of the crossroads, and the prefabricated prestressed concrete surface layer is arranged at the non-intersection parts in four directions of the crossroads. This is because the roadbed pretensioned slabs only have compressive self-stress in the longitudinal direction (i.e., the driving direction), so it is not suitable to be used as the surface layer at the intersection part of the crossroads that is stressed in all directions. Instead, the cast-in-place self-stress surface layer 4 with self-stress in both directions is adopted at the intersection part of the crossroads.
[0018] The precast prestressed concrete surface layer at the non-crossing part of the crossroads in each direction is composed of the left surface layer plate 15 and the right surface layer plate 16. Both the left surface layer plate 15 and the right surface layer plate 16 are composed of the inner pretensioned plate 1 and the edge pretensioned plate 2. The outside of the edge pretensioned plate 2 is the crossing part of the crossroads. For the concrete road surface, the number of the inner pretensioned plates 1 is more than one, and a certain number of the inner pretensioned plates 1 are laid to form the concrete road surface. The inner pretensioned plate 2 is connected to the inner pretensioned plate 1 through the transverse self-stress joint 3. Correspondingly, two adjacent inner pretensioned plates 2 are also connected through the transverse self-stress joint 3. A temperature joint 5 is arranged between the left surface layer plate 15 and the right surface layer plate 16.
[0019] The cast-in-place self-stress surface layer 4 shown is composed of the expansive concrete 8, the self-stress transverse bars 6 and the self-stress longitudinal bars 7 cast in the expansive concrete 8. The self-stress transverse bars 6 and the self-stress longitudinal bars 7 are evenly spaced and perpendicular to each other. The end parts of the edge pretensioned plates 2 are evenly anchored with the anchor bars 17, and the anchor bars 17 are connected to the end parts of the self-stress transverse bars 6 and the self-stress longitudinal bars 7 in the cast-in-place self-stress surface layer 4. In this way, the two opposite edge pretensioned plates 2 on both sides of the crossing part of the crossroads are fixedly connected together through the anchor bars 17 and the self-stress transverse bars 6 or the self-stress longitudinal bars 7.
[0020] During construction, first, the precast prestressed concrete surface layer is laid, and then the cast-in-place self-stress surface layer 4 is poured. During the process of the expansion and solidification of the expansive concrete 8 in the cast-in-place self-stress surface layer 4, pressure will be applied to the edge pretensioned plates 2 on both sides of it. At the same time, the edge pretensioned plates 2 will generate a reverse pressure on the cast-in-place self-stress surface layer 4. In this way, the cast-in-place self-stress surface layer 4 generates bidirectional self-stress in the longitudinal and transverse directions, enabling it to withstand the complex forces at the crossing part of the crossroads, which is beneficial to improving the durability of the road surface at the plane intersection.
[0021] The pretensioned plate constituting the precast prestressed concrete surface layer is composed of the pretensioned plate concrete 11, the steel strands 9 and the pretensioned plate transverse bars 10 cast in the pretensioned plate concrete 11. The steel strands 9 and the pretensioned plate transverse bars 10 are evenly arranged and perpendicular to each other in the pretensioned plate concrete 11. The length direction of the steel strands 9 is consistent with the length direction of the pretensioned plate, that is, along the driving direction of the road, and the length direction of the pretensioned plate transverse bars 10 is consistent with the road width direction. During the prefabrication process of the pretensioned plate, after the steel strands 9 are tensioned and released, longitudinal compressive stress will be generated in the pretensioned plate, enabling it to withstand the tensile stress generated by the vehicle during driving and being suitable for use as a road surface slab.
[0022] The horizontal self-stress joint 3 shown is composed of high-expansion concrete 14, longitudinal self-stress joint reinforcement bars 12 and transverse self-stress joint reinforcement bars 13 cast in the high-expansion concrete 14. The longitudinal self-stress joint reinforcement bars 12 are in the same direction as the length of the 3-layer of the self-stress joint, that is, along the road width direction, and the transverse self-stress joint reinforcement bars 13 are in the same direction as the driving direction. The transverse self-stress joint reinforcement bars 13 are formed by welding the anchor bars respectively anchored at the ends of the inner pretensioned slab 1 and the edge pretensioned slab 2. It can be seen that the inner pretensioned slab 1 and the edge pretensioned slab 2 are not only firmly connected by the horizontal self-stress joint 3 to jointly bear the vehicle load, but also the high-expansion concrete 14 in the horizontal self-stress joint 3 generates compressive stress on the ends of the pretensioned slabs, which can effectively avoid the occurrence of transverse cracks at the ends of the pretensioned slabs. The temperature joint 5 shown is formed by pouring and solidifying hot asphalt with a width of 2 mm to 4 mm and a height of 20 cm to 24 cm to adapt to the thermal expansion and contraction of the pretensioned slabs caused by temperature changes.
[0023] As specific requirements, the width of the pretensioned slab is 3.50 m to 3.75 m, the length is 6.0 m to 9.0 m, the thickness is 20 cm to 24 cm, the grade of the pretensioned slab concrete 11 is 40 MPa to 45 MPa, and the steel strands 9 are arranged at a position 1 cm to 2 cm below the central axis of the cross-section of the pretensioned slab.
[0024] The width of the horizontal self-stress joint 3 is 20 cm to 30 cm, the height is 20 cm to 24 cm, the grade of the high-expansion concrete 14 is 40 MPa to 45 MPa, and the longitudinal pressure value generated by the high-expansion concrete in the horizontal self-stress joint is 4 MPa to 5 MPa. The grade of the expansive concrete 8 in the cast-in-place self-stress surface layer 4 is 40 MPa to 45 MPa, and the self-stress values generated by the expansive concrete in the longitudinal and transverse directions after pouring are 2 MPa to 4 MPa.
Claims
1. A prestressed concrete surface layer structure for a cross intersection, comprising a prefabricated prestressed concrete surface layer and a cast-in-place self-stressing surface layer (4), wherein the prefabricated prestressed concrete surface layer is composed of pretensioned slabs laid evenly; characterized in that: The cast-in-place self-stressing surface layer is laid at the intersection part of the crossroads, and the precast prestressed concrete surface layer is laid at the non-intersection parts in four directions of the crossroads; the precast prestressed concrete surface layer at the non-intersection parts of the crossroads is composed of the left surface layer plate (15) and the right surface layer plate (16). Both the left surface layer plate and the right surface layer plate include the edge pretensioned plate (2) and the inner pretensioned plate (1). The edge pretensioned plate and the inner pretensioned plate are connected by a transverse self-stressing joint (3). A temperature joint (5) is arranged between the left surface layer plate and the right surface layer plate; the cast-in-place self-stressing surface layer is composed of expansive concrete (8) and self-stressing transverse bars (6) and self-stressing longitudinal bars (7) cast therein. The outer end of the edge pretensioned plate is anchored with anchor bars (17) welded to the self-stressing transverse bars and self-stressing longitudinal bars.
2. The prestressed concrete surface layer structure of the cross intersection according to claim 1, characterized in that: The pretensioned plate is composed of pretensioned plate concrete (11) and steel strands (9) and pretensioned plate transverse bars (10) cast therein. The length direction of the steel strands is consistent with the driving direction of the road, and the pretensioned plate transverse bars are consistent with the width direction of the road.
3. The prestressed concrete surface layer structure of the cross intersection according to claim 1 or 2, characterized in that: The transverse self-stressing joint (3) is composed of high-expansion concrete (14) and self-stressing joint longitudinal bars (12) and self-stressing joint transverse bars (13) cast therein. The length direction of the self-stressing joint longitudinal bars is consistent with the width direction of the road. The self-stressing joint transverse bars are formed by welding anchor bars respectively anchored at the ends of the inner pretensioned plate (1) and the edge pretensioned plate (2).
4. The prestressed concrete surface layer structure of the cross intersection according to claim 2, characterized in that: The width of the pretensioned plate is 3.50 m to 3.75 m, the length is 6.0 m to 9.0 m, and the thickness is 20 cm to 24 cm. The grade of the pretensioned plate concrete (11) is 40 MPa to 45 MPa. The steel strands (9) are arranged at a position 1 cm to 2 cm below the central axis of the cross-section of the pretensioned plate.
5. The prestressed concrete surface layer structure of the cross intersection according to claim 3, characterized in that: The width of the transverse self-stressing joint (3) is 20 cm to 30 cm, the height is 20 cm to 24 cm. The grade of the high-expansion concrete (14) is 40 MPa to 45 MPa. The longitudinal pressure value generated by the high-expansion concrete in the transverse self-stressing joint is 4 MPa to 5 MPa.
6. The prestressed concrete surface layer structure of the cross intersection according to claim 1 or 2, characterized in that: The temperature joint (5) is formed by pouring and solidifying hot asphalt with a width of 2 mm to 4 mm and a height of 20 cm to 24 cm.
7. The prestressed concrete surface layer structure of the cross intersection according to claim 1 or 2, characterized in that: The grade of the expansive concrete (8) in the cast-in-place self-stressing surface layer (4) is 40 MPa to 45 MPa. The self-stressing values generated by the expansive concrete after pouring in the longitudinal direction and the transverse direction are 2 MPa to 4 MPa.