Bidirectional four-lane overhaul engineering road structure

Abstract

The bidirectional four-lane overhaul project road structure comprises a wheel protecting belt, an overtaking lane, a traffic lane and a hard road shoulder which are sequentially distributed from left to right, and the wheel protecting belt, the overtaking lane and the hard road shoulder are composed of a lower base layer, an upper base layer and an asphalt surface layer which are distributed from bottom to top; the overtaking lane is characterized in that the traffic lane is composed of a lower base layer, a part of an upper base layer, an asphaltic sand layer and an assembly type prestressed concrete surface layer which are distributed from bottom to top, the assembly type prestressed concrete surface layer is composed of road pre-tensioning plates which are evenly laid, and the left side and the right side of the assembly type prestressed concrete surface layer are connected with the overtaking lane and the hard road shoulder through temperature joints. According to the bidirectional four-lane overhaul engineering road structure, the asphaltic sand layer and the assembly type prestressed concrete surface layer are sequentially arranged in the milled overtaking lane area from bottom to top, and the overtaking lane after overhaul and reconstruction has excellent bearing capacity by utilizing the characteristic that the pre-tensioning plate has good compression strength, so that the service life of the road surface is prolonged.

Description

Technical Field

[0001] The utility model relates to a road structure, and more specifically, to a road structure for a two-way four-lane major repair project. Background Technique

[0002] With the rapid development of China's economy, there is more and more heavy traffic. For a two-way four-lane road, heavy trucks with a large load will drive on the driving lane (i.e., the right lane, also known as the slow lane) for a long time. Coupled with the frequent occurrence of high-temperature weather in China, this has led to an increasing number of ruts on the driving lane of the two-way four-lane road. Especially for roads with a large traffic volume on the driving lane, the ruts are particularly serious. At present, the method to solve the rut problem on the driving lane is to add rut-resistant agents to the asphalt surface layer materials, but the effect is not obvious, and the problem of rut formation and appearance still cannot be solved. Therefore, the utility model proposes a road structure for a two-way four-lane major repair project to solve the problem that ruts are likely to appear on the driving lane. Summary of the Invention

[0003] The utility model provides a road structure for a two-way four-lane major repair project to overcome the above technical problems.

[0004] The road structure for a two-way four-lane major repair project of the utility model includes a curb, an overtaking lane, a driving lane, and a hard shoulder that are distributed in sequence from left to right. The curb, overtaking lane, and hard shoulder are composed of a lower base course, an upper base course, and an asphalt surface layer that are distributed from bottom to top; its characteristics are: the driving lane is composed of a lower base course, a part of the upper base course, an asphalt sand layer, and an assembled prestressed concrete surface layer from bottom to top. The assembled prestressed concrete surface layer is composed of road-use pretensioned slabs laid evenly. The left and right sides of the assembled prestressed concrete surface layer are connected to the overtaking lane and the hard shoulder through temperature joints.

[0005] In the road structure for a two-way four-lane major repair project of the utility model, the temperature joint is composed of a hot asphalt layer and an asphalt sand joint. The hot asphalt layer is formed by the cooling of the asphalt surface layer sprayed on the outer side of the pretensioned slab and the hot asphalt on the outer facade of a part of the upper base course. The asphalt sand joint is formed by the asphalt sand filled between the hot asphalt layer and the outer facade of the pretensioned slab.

[0006] In the road structure for a two-way four-lane major repair project of the utility model, both the lower base course and the upper base course are composed of cement stabilized macadam. The thickness of the upper base course and the lower base course is 15 cm to 27 cm, the strength of the lower base course is 2.5 MPa to 4.0 MPa, and the strength of the upper base course is 4.0 MPa to 6.0 MPa.

[0007] The road structure of the two-way four-lane overhaul project of the present utility model is such that adjacent pretensioned slabs forming the precast prestressed concrete surface layer are connected by self-stressing joints. The pretensioned slab is composed of ordinary concrete, steel strands and transverse steel bars cast therein. The length direction of the steel strands is the same as the length direction of the pretensioned slab, and the length direction of the transverse steel bars is the same as the width direction of the pretensioned slab.

[0008] The road structure of the two-way four-lane overhaul project of the present utility model, the self-stressing joint is composed of high-expansion concrete and longitudinal self-stressing bars and transverse self-stressing bars cast therein. The length direction of the longitudinal self-stressing bars is the same as the length direction of the pretensioned slab, and the length direction of the transverse self-stressing bars is the same as the width direction of the pretensioned slab.

[0009] The road structure of the two-way four-lane overhaul project of the present utility model, the grade of the ordinary concrete forming the pretensioned slab is 35MPa - 45MPa, and the steel strands are located 1cm - 3cm below the central axis of the cross-section of the pretensioned slab; the grade of the high-expansion concrete forming the self-stressing joint is 35MPa - 45MPa, and the longitudinal self-stress value generated by the self-stressing joint is 3MPa - 5MPa.

[0010] The road structure of the two-way four-lane overhaul project of the present utility model, the thickness of the asphalt sand layer is 2cm - 3cm, the width of the asphalt sand joint is 5cm - 7cm, and the height of the asphalt sand joint is equal to the thickness of the pretensioned slab.

[0011] The beneficial effect of the present utility model is: For the road structure of the two-way four-lane overhaul project of the present utility model, the curb, overtaking lane and hard shoulder are composed of a lower base course, an upper base course and an asphalt surface layer arranged from bottom to top in sequence. In view of the phenomenon that the overtaking lane is prone to rutting due to long-term rolling by heavily loaded vehicles, the overtaking lane is excavated (such as milling with a milling machine) to part of the upper base course, and then an asphalt sand layer and a precast prestressed concrete surface layer are arranged from bottom to top in sequence in the milled overtaking lane area to form a new type of overtaking lane. By utilizing the characteristic that the precast prestressed concrete surface layer composed of pretensioned slabs has good compressive strength, the overtaking lane in the two-way four-lane road after overhaul and reconstruction has excellent bearing capacity, solves the problem that the existing overtaking lane is prone to rutting, and greatly improves the service life of the road surface. Description of the Drawings

[0012] Figure 1 It is a top view of the road structure of the two-way four-lane overhaul project of the present utility model;

[0013] Figure 2 It is a cross-sectional schematic diagram of the road structure of the two-way four-lane overhaul project of the present utility model;

[0014] Figure 3 It is a longitudinal sectional view of the precast prestressed concrete surface layer in the present utility model.

[0015] In the figure: 1 is the driving lane, 2 is the overtaking lane, 3 is the curb, 4 is the hard shoulder, 5 is the pre-tensioned slab, 6 is the self-stressing joint, 7 is the temperature joint, 8 is the lower base course, 9 is the upper base course, 10 is the asphalt surface course, 11 is the asphalt sand layer, 12 is the hot asphalt layer, 13 is the asphalt sand joint, 14 is ordinary concrete, 15 is the steel strand, 16 is the transverse steel bar, 17 is the high-expansion concrete, 18 is the longitudinal self-stressing bar, 19 is the transverse self-stressing bar. Specific embodiments

[0016] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0017] As Figure 1 and Figure 2 shown, the top view and cross-sectional schematic diagram of the road structure of the two-way four-lane overhaul project of the present invention are respectively given. The road structure of the two-way four-lane overhaul project is composed of the curb 3, overtaking lane 2, driving lane 1 and hard shoulder 4 distributed from left to right. The curb 3, overtaking lane 2 and hard shoulder 4 are composed of the lower base course 8, upper base course 9 and asphalt surface course 10 from bottom to top. The overtaking lane 1 (i.e., the driving lane, also known as the fast lane) is an asphalt road surface. For the driving lane 1 where rutting occurs and affects normal driving, it is excavated downward until part of the upper base course 9 is excavated, such as using a milling machine to mill to part of the upper base course 9. After the driving lane 1 is excavated downward, an asphalt sand layer 11 and a precast prestressed concrete surface layer are arranged from bottom to top.

[0018] The asphalt sand layer 11 is composed of asphalt sand laid on top of part of the upper base course 9. The precast prestressed concrete surface layer is composed of evenly laid pre-tensioned slabs 5. Adjacent two pre-tensioned slabs 5 in the longitudinal direction are connected by self-stressing joints 6. The left and right sides of the precast prestressed concrete surface are connected to the overtaking lane 2 and the hard shoulder 4 through temperature joints 7. The temperature joint 7 has the function of offsetting the thermal expansion and contraction of the pre-tensioned slab 5 when the temperature changes, and the temperature joint 7 can also prevent rainwater from entering the lower upper base course 9.

[0019] It can be seen that for the road structure of the two-way four-lane overhaul project of the present invention, the driving lane 1 with rutting is excavated and the asphalt sand layer 11 and the precast prestressed concrete surface layer are laid. The pre-tensioned slab 5 that constitutes the precast prestressed concrete surface layer has good compressive performance, so that the formed driving lane 1 has rutting resistance under heavy traffic and extends the service life of the road surface.

[0020] The shown temperature joint 7 is composed of a hot asphalt layer 12 and an asphalt sand joint 13. The hot asphalt layer 12 is formed by the cooling of the asphalt surface layer 10 sprayed on the outer side of the pretensioned slab 5 and the hot asphalt on the outer facade of a part of the upper base course 9. The asphalt sand joint 13 is formed by the asphalt sand filled between the hot asphalt layer 12 and the outer facade of the pretensioned slab 5. In this way, by utilizing the water impermeability and good ductility of asphalt, it can not only prevent rainwater from entering the lower upper base course 9, but also accommodate the width change of the temperature joint 7 caused by the thermal expansion and contraction of the pretensioned slab 5.

[0021] As Figure 3 shown, a longitudinal cross-section view of the precast prestressed concrete surface layer in the present utility model is given. The pretensioned slab 5 that constitutes the precast prestressed concrete surface layer is composed of ordinary concrete 14, steel strands 15 and transverse steel bars 16 cast in the ordinary concrete 14. The length direction of the steel strands 15 is consistent with the length direction of the pretensioned slab 5, that is, along the road driving direction; the length direction of the transverse steel bars 16 is consistent with the width direction of the pretensioned slab 5, that is, along the road width direction. During the prefabrication process of the pretensioned slab 5, after the tensile force applied to the pretensioned slab 5 is withdrawn, the pretensioned slab will have a compressive stress in the longitudinal direction to offset the tensile stress generated by vehicle driving when it is used as a road surface slab.

[0022] The self-stress joint 6 connecting two adjacent pretensioned slabs 5 shown is composed of high-expansion concrete 17, longitudinal self-stress bars 18 and transverse self-stress bars 19 cast in the high-expansion concrete 17. The longitudinal self-stress bars 18 are consistent with the length direction of the pretensioned slab 5, and the transverse self-stress bars 19 are consistent with the width direction of the pretensioned slab 5. The longitudinal self-stress bars 18 are formed by welding two sections of steel bars, and the two sections of steel bars are embedded in the outer end faces of the pretensioned slab 5.

[0023] The shown lower base course 8 and upper base course 9 are both composed of cement-stabilized macadam. The thicknesses of the upper base course 8 and the lower base course 9 are both 15 cm to 27 cm. The strength of the lower base course 8 is 2.5 MPa to 4.0 MPa, and the strength of the upper base course 9 is 4.0 MPa to 6.0 MPa. The grade of the ordinary concrete 14 that constitutes the pretensioned slab 5 is 35 MPa to 45 MPa, and the steel strands 15 are located 1 cm to 3 cm below the central axis of the cross-section of the pretensioned slab 5; the grade of the high-expansion concrete 17 that constitutes the self-stress joint 6 is 35 MPa to 45 MPa, and the longitudinal self-stress value generated by the self-stress joint 6 is 3 MPa to 5 MPa. The thickness of the asphalt sand layer 11 is 2 cm to 3 cm, the width of the asphalt sand joint 13 is 5 cm to 7 cm, and the height of the asphalt sand joint 13 is equal to the thickness of the pretensioned slab 5.

[0024] In summary, for the road structure of the two-way four-lane overhaul project of the present utility model, when the driving lane 1 of the two-way four-lane road is affected by rutting and affects the normal driving of vehicles, the driving lane 1 is excavated downward, and a part of the upper base course 9 is removed. Then, an asphalt sand layer 11 is laid. Next, hot asphalt is sprayed on the outer surface of the asphalt surface course 10 outside the pretensioned slab 5 and a part of the outer surface of the upper base course 9 and cooled to form a hot asphalt layer 12. Then, the pretensioned slab 5 is laid, and adjacent pretensioned slabs 5 are connected by self-stressing joints 6. Finally, asphalt sand is filled between the hot asphalt layer and the outer surface of the pretensioned slab to form an asphalt sand joint 13.

Claims

1. A road structure for a two-way four-lane overhaul project, including a curb (3), an overtaking lane (2), a driving lane (1), and a hard shoulder (4) distributed in sequence from left to right. The curb, overtaking lane, and hard shoulder are composed of a lower base course (8), an upper base course (9), and an asphalt surface course (10) distributed from bottom to top; it is characterized in that: The carriageway consists of a lower base course, a partial upper base course, an asphalt sand layer (11), and a precast prestressed concrete surface course that are distributed from bottom to top. The precast prestressed concrete surface course is composed of road-use pretensioned slabs (5) laid evenly. The left and right sides of the precast prestressed concrete surface course are connected to the overtaking lane and the hard shoulder through temperature joints (7).

2. The road structure of the two-way four-lane major overhaul project according to claim 1, characterized in that: The temperature joint (7) consists of a hot asphalt layer (12) and an asphalt sand joint (13). The hot asphalt layer is formed by the cooling of the asphalt surface course (10) sprayed on the outer side of the pretensioned slab (5) and the hot asphalt on the outer facade of the partial upper base course (9). The asphalt sand joint is formed by the asphalt sand filled between the hot asphalt layer and the outer facade of the pretensioned slab.

3. The road structure of the two-way four-lane major overhaul project according to claim 1 or 2, characterized in that: Both the lower base course (8) and the upper base course (9) are composed of cement stabilized macadam. The thickness of the upper base course and the lower base course is 15 cm to 27 cm. The strength of the lower base course is 2.5 MPa to 4.0 MPa, and the strength of the upper base course is 4.0 MPa to 6.0 MPa.

4. The road structure of the two-way four-lane major repair project according to claim 1 or 2, characterized in that: Adjacent pretensioned slabs (5) that make up the precast prestressed concrete surface course are connected through self-stressing joints (6). The pretensioned slab is composed of ordinary concrete (14), steel strands (15) and transverse steel bars (16) cast therein. The length direction of the steel strands is consistent with the length direction of the pretensioned slab, and the length direction of the transverse steel bars is consistent with the width direction of the pretensioned slab.

5. The road structure of the two-way four-lane major repair project according to claim 4, characterized in that: The self-stressing joint (6) consists of high-expansion concrete (17), longitudinal self-stressing bars (18) and transverse self-stressing bars (19) cast therein. The length direction of the longitudinal self-stressing bars is consistent with the length direction of the pretensioned slab (5), and the length direction of the transverse self-stressing bars is consistent with the width direction of the pretensioned slab.

6. The road structure of the two-way four-lane major overhaul project according to claim 5, characterized in that: The grade of the ordinary concrete (14) that makes up the pretensioned slab (5) is 35 MPa to 45 MPa, and the steel strands (15) are located 1 cm to 3 cm below the central axis of the cross-section of the pretensioned slab; the grade of the high-expansion concrete (17) that makes up the self-stressing joint (6) is 35 MPa to 45 MPa, and the longitudinal self-stress value generated by the self-stressing joint is 3 MPa to 5 MPa.

7. The road structure of the two-way four-lane major overhaul project according to claim 2, characterized in that: The thickness of the asphalt sand layer (11) is 2 cm to 3 cm, the width of the asphalt sand joint (13) is 5 cm to 7 cm, and the height of the asphalt sand joint is equal to the thickness of the pretensioned slab (5).

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