Paving structure of expansion-joint-free low-noise bridge deck

Abstract

The utility model discloses a pavement structure of a non-expansion joint low-noise bridge floor, which sequentially comprises a stable layer, a waterproof crack-inhibiting layer, a sliding layer, a middle surface layer and an upper surface layer from bottom to top, each layer is a continuous pavement layer, and the surface is non-expansion joint; a gap is formed between the beam body and the bridge abutment, and an anti-leakage net is arranged at the one-third depth position of the gap; a first arc is arranged between the gap and the abutment, the circle center corresponding to the first arc and the leakage-proof net are located on the same horizontal line, the central angle corresponding to the first arc is 90 degrees, and the radius of the corresponding circle is one third of the depth of the gap; a second arc is arranged between the gap and the beam body, the circle center corresponding to the second arc and the leakage-proof net are located on the same horizontal line, and the circle radius corresponding to the second arc is two thirds of the depth of the gap. According to the bridge deck pavement structure, the asphalt mixture is paved in a continuous through paving mode, no expansion joint exists in the whole structure and all layers of structures, the bridge deck pavement can reduce traffic noise, and the problem that the bridge deck pavement is high in noise is solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of road and bridge construction engineering, and specifically relates to a pavement structure of a low-noise bridge deck without expansion joints. The pavement structure is suitable for small and medium-sized bridges and can effectively reduce the traffic noise level of small and medium-sized bridges. Background Art

[0002] As we all know, when bridges are required at special locations such as rivers or existing highways, the bridge deck should be paved with asphalt to ensure drivability. For small and medium-sized bridges, since the bridge beams and abutments are made of cement concrete, which has significant thermal expansion and contraction, a gap must be left between the beams and abutments to ensure the beams can expand and contract freely under these thermal expansion and contraction effects.

[0003] If asphalt pavement is directly laid over the gap between the beam and the abutment, the asphalt pavement material will be susceptible to cracking due to thermal expansion and contraction, uneven settlement, and other effects, leading to damage to the asphalt pavement. Existing technologies typically install expansion joints between the beam and the abutment, paving the asphalt pavement on both sides of the expansion joints to prevent cracking. However, compared to flexible materials such as asphalt mixtures, expansion joints made of rigid materials such as concrete and steel lack a cushioning effect when in contact with vehicle tires. Furthermore, bridgeheads generally experience varying degrees of settlement, and moving vehicles can collide violently with the asphalt pavement due to the bouncing effect. These side effects lead to significant traffic noise pollution on bridge decks, especially at bridgeheads, where the problem is more severe. Therefore, eliminating expansion joints is an effective way to avoid traffic noise pollution from bridges. However, in this case, the technical issue of asphalt pavement being easily damaged by thermal expansion and contraction or uneven settlement must be considered. Therefore, it is necessary to develop a low-noise bridge deck pavement structure without expansion joints to address the problems of the existing technology.

[0004] Utility model patent CN209686234U discloses a seamless, monolithic bridge asphalt pavement structure. This structure involves installing a cover plate above the telescopic ends of two adjacent beams to completely cover the expansion joint between them. Below the cover plate is the beam expansion joint, allowing the beams to expand and contract longitudinally. Above the cover plate is a monolithic asphalt pavement with no expansion joints, thus achieving a seamless, monolithic bridge asphalt pavement. This technical solution is suitable for seamless asphalt pavement on large bridges (i.e., long bridges with gaps between adjacent beams). Utility Model Content

[0005] In order to solve the problems existing in the prior art, the utility model provides a pavement structure for a low-noise bridge deck without expansion joints. The pavement structure is laid above the beam body and the abutment. The pavement structure consists of five layers, which are, from bottom to top, a stabilizing layer, a waterproof crack-inhibiting layer, a sliding layer, a middle surface layer and an upper surface layer. Each layer in the pavement structure is a continuous pavement layer with no expansion joints on the layer surface. A gap is provided between the beam body and the abutment, and a leak-proof net is provided at one-third of the depth of the gap.

[0006] A first arc is set between the gap and the abutment, the center of the first arc is on the same horizontal line as the anti-leakage net, the central angle of the first arc is 90 degrees, and the radius of the first arc is one-third of the depth of the gap; a second arc is set between the gap and the beam body, the center of the second arc is on the same horizontal line as the anti-leakage net, and the radius of the second arc is two-thirds of the depth of the gap.

[0007] Preferably, the length of the beam does not exceed 100m, and the thickness of the beam is 15-20cm; the length of the abutment is 5m, and the thickness of the abutment is the same as the thickness of the beam; the width of the gap is 5-20mm, and the depth of the gap is the same as the thickness of the beam.

[0008] In any of the above solutions, preferably, a plurality of circular holes are provided on the anti-leakage net, and the diameter of the circular holes is 1-2 mm.

[0009] In any of the above schemes, it is preferred that the stabilizing layer is a high-strength and high-toughness asphalt mortar layer, which is prepared with polymer binder, high-strength sand and filler, with a thickness of 1-3 cm, a dynamic stability at 60°C of 50,000 times / mm, and a low-temperature bending failure strain of -10°C of 5000 με.

[0010] In any of the above schemes, it is preferred that the waterproof crack inhibition layer is paved with asphalt or polymer waterproof membrane with a thickness of 2-5 mm, a high temperature shear resistance of greater than 2.5 N / mm at 60°C, and a low temperature crack resistance of greater than 8 MPa at -20°C.

[0011] In any of the above schemes, it is preferred that the sliding layer is composed of a composite of three layers, which are, from bottom to top, a first ball layer, a bearing plate and a second ball layer; the balls in the first ball layer and the second ball layer are any one of river sand, corundum and steel balls, and their particle size is a single particle size in the range of 1.18-2.36mm, and the thickness of the first ball layer and the second ball layer is 1-5mm; the bearing plate is a steel plate, and its thickness is 5-10mm.

[0012] In any of the above schemes, it is preferred that the middle surface layer is paved with asphalt mixture with a thickness of 5-7 cm; the nominal maximum aggregate particle size of the asphalt mixture is any one of 13.2 mm, 16 mm, 20 mm, and 25 mm, and the type of the asphalt mixture is asphalt concrete AC, mastic asphalt crushed stone mixture SMA, or large-void asphalt mixture PAC.

[0013] In any of the above schemes, it is preferred that the upper layer is paved with large-void asphalt mixture or high-damping asphalt mixture, and its thickness is 3-5 cm; the void ratio of the large-void asphalt mixture is greater than 20%, and the peak sound absorption coefficient is greater than 0.8; the damping ratio of the high-damping asphalt mixture is greater than 40%.

[0014] The pavement structure of the utility model with no expansion joints and low noise bridge deck has the following beneficial effects:

[0015] (1) The pavement structure of the present invention consists of five layers. The overall structure is located above the beam and the abutment. The pavement structure adopts a continuous paving method to pave the asphalt mixture. The overall structure and each layer structure do not have expansion joints. Compared with the traditional paving structure with expansion joints, the pavement structure of the present invention can effectively avoid traffic noise pollution caused by the bridge. When the vehicle is driving, the traffic noise can be reduced by more than 10dB, thereby solving the technical problem of high noise in the bridge pavement.

[0016] (2) A stabilization layer is first laid on the beam, abutment and the gap between them. The stabilization layer can make the overall structure stable and durable and not prone to deformation. When the beam expands and contracts or vibrates and shears up and down, the stabilization layer can absorb stress and prevent the asphalt pavement from cracking. At the same time, the stress absorbed by the stabilization layer will not continue to be transmitted upward, thereby ensuring the durability of the upper structure.

[0017] (3) A waterproof crack-inhibiting layer is laid on top of the stabilization layer. When rainwater, snow water, etc. that seep from the road surface or roadside penetrate into the waterproof crack-inhibiting layer, they will not continue to seep down, thus preventing the bridge concrete and steel bars from being corroded by water. At the same time, the waterproof crack-inhibiting layer can further buffer the stress generated by the thermal expansion and contraction of the beam body or the up and down vibration shear.

[0018] (4) A sliding layer is laid between the waterproof crack suppression layer and the middle surface layer. The sliding layer can deform freely in the longitudinal direction following the expansion and contraction of the bridge deck, while the middle surface layer and the upper surface layer will not deform due to the rolling action of the balls, and therefore will not crack due to the thermal expansion and contraction of the bridge deck. Specifically, the middle of the sliding layer is a steel plate, and the balls are spread on the upper and lower surfaces, which mainly play the role of free sliding. That is, the sliding layer divides the entire pavement structure into two major layers: the middle surface layer and the layers above it, and the waterproof crack suppression layer and the layers below it. These two layers maintain relatively independent deformation. Due to the existence of the sliding layer, they do not interfere with each other. This completely solves the impact of deformation and stress caused by thermal expansion and contraction of the beam body or vertical vibration and shear on the asphalt pavement layer.

[0019] (5) A leak-proof net is set at one-third of the depth of the gap. The leak-proof net can prevent the stabilization layer material from falling into the deep gap. If all the stabilization layer materials fall into the gap, the stabilization layer becomes incomplete, resulting in instability of the overall structure.

[0020] (6) Asymmetric arcs are set between the gap and the abutment, and between the gap and the beam body. This setting method can avoid stress concentration in the overall structure. In addition, under the action of traffic load and the weight of the overall structure, setting a second arc with a relatively smaller curvature can further reduce the stress concentration phenomenon. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of a preferred embodiment of the pavement structure of a low-noise bridge deck without expansion joints according to the utility model;

[0022] Figure 2 for Figure 1 A schematic diagram of the positional relationship between the gap, the beam body and the abutment in the embodiment shown;

[0023] Figure 3 for Figure 1 Schematic diagram of the structure of the sliding layer in the embodiment shown.

[0024] Explanation of the markings in the figure: 1- beam body, 2- abutment, 3- stabilizing layer, 4- waterproof and crack-inhibiting layer, 5- sliding layer, 501- first ball bearing layer, 502- bearing plate, 503- second ball bearing layer, 6- middle surface layer, 7- upper layer, 8- gap, 9- anti-leakage net, 10- first arc, 11- second arc. DETAILED DESCRIPTION

[0025] In order to further understand the content of the present invention, the present invention will be described in detail below with reference to specific embodiments.

[0026] Example 1:

[0027] like Figure 1-2As shown, according to a preferred embodiment of the pavement structure of the low-noise bridge deck without expansion joints of the utility model, the pavement structure is laid above the beam body 1 and the abutment 2. The pavement structure consists of five layers, which are, from bottom to top, a stabilizing layer 3, a waterproof crack-inhibiting layer 4, a sliding layer 5, a middle surface layer 6 and an upper layer 7. Each layer in the pavement structure is a continuous pavement layer with no expansion joints on the surface. A gap 8 is provided between the beam body 1 and the abutment 2, and a leak-proof net 9 is provided at a position one-third of the depth of the gap 8.

[0028] A first circular arc 10 is arranged between the gap 8 and the abutment 2, the center of the first circular arc 10 is on the same horizontal line as the anti-leakage net 9, the central angle of the first circular arc 10 is 90 degrees, and the radius of the circle of the first circular arc 10 is one-third of the depth of the gap 8; a second circular arc 11 is arranged between the gap 8 and the beam body 1, the center of the second circular arc 11 is on the same horizontal line as the anti-leakage net 9, and the radius of the circle of the second circular arc 11 is two-thirds of the depth of the gap 8.

[0029] The beam 1 is 100 meters long and 20 centimeters thick; the abutment 2 is 5 meters long and the same thickness as the beam 1; the slit 8 is 20 millimeters wide and the same depth as the thickness of the beam 1. The anti-leakage net 9 has a plurality of circular holes with a diameter of 1.5 millimeters.

[0030] The stabilization layer 3 is a high-strength, high-toughness asphalt mortar layer made from a polymer binder, high-strength sand, and fillers. It is 2 cm thick, has a dynamic stability of 50,000 times / mm at 60°C, and a low-temperature bending failure strain of 5000 με at -10°C. The waterproof crack suppression layer 4 is made of SBS-modified asphalt waterproof membrane, 4 mm thick, has a high-temperature shear resistance of 5.6 N / mm at 60°C, and a low-temperature crack resistance of 12.4 MPa at -20°C.

[0031] like Figure 3 As shown, the sliding layer 5 is composed of three composite layers, which are, from bottom to top, the first ball layer 501, the bearing plate 502 and the second ball layer 503; the balls in the first ball layer 501 and the second ball layer 503 are both corundum with a particle size of 2.36 mm, and the thickness of the first ball layer 501 and the second ball layer 503 are both 3 mm; the bearing plate 502 is a steel plate with a thickness of 8 mm.

[0032] The middle surface layer 6 is paved with an asphalt mixture with a thickness of 5 cm. The asphalt mixture has a nominal maximum aggregate size of 20 mm and is of AC asphalt concrete. The upper layer 7 is paved with a large-void asphalt mixture with a thickness of 3 cm. The large-void asphalt mixture has a void ratio of 22% and a peak sound absorption coefficient of 0.85.

[0033] The pavement structure of the low-noise bridge deck without expansion joints in this embodiment has the following beneficial effects: (1) The pavement structure consists of five layers. The overall structure is located above the beam and the abutment. The asphalt mixture is paved in a continuous paving manner. The overall structure and each layer of the structure have no expansion joints. The pavement structure can effectively avoid traffic noise pollution caused by the bridge and reduce traffic noise by more than 10dB when vehicles are driving, thereby solving the technical problem of high noise in the bridge pavement. (2) A stabilization layer is first laid above the beam, the abutment and the gap between them. The stabilization layer can make the overall structure stable and durable and not easy to deform. (3) A waterproof crack-inhibiting layer is laid above the stabilization layer. When rainwater, snow water, etc. that seeps from the road surface or the roadside penetrates into the waterproof crack-inhibiting layer, it will not continue to seep into the waterproof crack-inhibiting layer, thereby preventing the bridge concrete and steel bars from being corroded by water. At the same time, the waterproof crack-inhibiting layer can further buffer the stress generated by the thermal expansion and contraction of the beam or the up and down vibration shear. (4) A sliding layer is laid between the waterproof crack suppression layer and the middle surface layer. The sliding layer can deform freely in the longitudinal direction following the expansion and contraction of the bridge deck, while the middle surface layer and the upper layer will not deform due to the rolling action of the balls, and therefore will not crack due to the thermal expansion and contraction of the bridge deck. (5) A leak-proof net is set at one-third of the depth of the gap. The leak-proof net can prevent the stabilization layer material from falling into the deep gap. If the stabilization layer material falls into the gap, the stabilization layer becomes incomplete, resulting in instability of the overall structure. (6) Asymmetric arcs are set between the gap and the abutment, and between the gap and the beam body. This setting method can avoid stress concentration in the overall structure. In addition, under the action of traffic load and the weight of the overall structure, setting a second arc with a relatively small curvature can further reduce stress concentration.

[0034] Example 2:

[0035] According to another preferred embodiment of the pavement structure of the utility model with no expansion joints and low noise, the number of layers of the pavement structure, the positional relationship between the layers, the technical principles and the beneficial effects are basically the same as those of the first embodiment, except that:

[0036] The length of the beam is 100m and the thickness is 15cm; the length of the abutment is 5m, and the thickness of the abutment is the same as the thickness of the beam; the width of the gap is 5mm, and the depth of the gap is the same as the thickness of the beam; a number of circular holes are opened on the anti-leakage net, and the diameter of the circular holes is 2mm.

[0037] The thickness of the stabilizing layer is 3cm. The thickness of the waterproof crack-suppressing layer is 5mm, the high-temperature shear resistance at 60℃ is 4.6N / mm, and the low-temperature crack resistance at -20℃ is 11.9MPa. The sliding layer is composed of three layers, which are the first ball layer, the bearing plate and the second ball layer from bottom to top. The balls in the first ball layer and the second ball layer are river sand with a particle size of 1.18mm. The thickness of the first ball layer and the second ball layer is 5mm; the bearing plate is a steel plate with a thickness of 10mm. The thickness of the middle surface layer is 7cm, and the nominal maximum aggregate particle size of the asphalt mixture is 16mm. The upper layer is paved with a large-void asphalt mixture with a thickness of 5cm. The void ratio of the large-void asphalt mixture is 23%, and the peak sound absorption coefficient is 0.88.

[0038] Example 3:

[0039] According to another preferred embodiment of the pavement structure of the utility model with no expansion joints and low noise, the number of layers of the pavement structure, the positional relationship between the layers, the technical principles and the beneficial effects are basically the same as those of the first embodiment, except that:

[0040] The length of the beam is 100m and the thickness is 18cm; the length of the abutment is 5m, and the thickness of the abutment is the same as the thickness of the beam; the width of the gap is 10mm, and the depth of the gap is the same as the thickness of the beam; a number of circular holes are opened on the anti-leakage net, and the diameter of the circular holes is 1mm.

[0041] The thickness of the stabilizing layer is 1 cm. The thickness of the waterproof crack-suppressing layer is 2 mm, the high-temperature shear resistance at 60°C is 5.1 N / mm, and the low-temperature crack resistance at -20°C is 12.3 MPa. The sliding layer is composed of three composite layers, which are, from bottom to top, the first ball layer, the bearing plate, and the second ball layer. The balls in the first ball layer and the second ball layer are all steel balls with a particle size of 2.36 mm. The thickness of the first ball layer and the second ball layer is 1 mm. The bearing plate is a steel plate with a thickness of 5 mm. The thickness of the middle surface layer is 6 cm, and the nominal maximum aggregate particle size of the asphalt mixture is 13.2 mm. The upper layer is paved with a large-void asphalt mixture with a thickness of 4 cm. The void ratio of the large-void asphalt mixture is 25%, and the peak sound absorption coefficient is 0.82.

[0042] Comparative Example:

[0043] This comparative example designed a conventional bridge deck pavement structure consisting of three layers: a rubberized asphalt chip seal, a 6cm AC-20 mid-surface, and a 4cm SMA-13 top layer. A concrete grommet was installed above the gap between the beam and the abutment.

[0044] The traffic noise of the above three embodiments and comparative examples was tested in accordance with "T 0986-2019 Statistical Method for Testing the Impact of Road Surface on Traffic Noise" in the "Field Testing Procedure for Highway Roadbed and Pavement" (JTG 3450-2019). The test results are shown in Table 1.

[0045] Table 1 Traffic noise test results of different pavement structures

[0046] Different pavement structures Traffic noise (dB) Example 1 92 Example 2 90.1 Example 3 91.6 Comparative Example 103.7

[0047] From the test results in Table 1, it can be seen that the pavement structure of the expansion joint-free low-noise bridge deck of the above three embodiments can effectively reduce the traffic noise level. The traffic noise is significantly lower than that of the pavement structure of the conventional bridge deck, with a reduction of more than 12.7%.

[0048] Those skilled in the art will readily appreciate that the expansion joint-free, low-noise bridge deck pavement structure of the present invention comprises any combination of the components described in the utility model specification and the detailed embodiments, as well as the components illustrated in the accompanying drawings. Due to space limitations and to maintain clarity, not all of the various schemes comprising these combinations are described. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model are intended to be included within the scope of protection of this utility model.

Claims

1. A paving structure for a bridge deck without expansion joints and with low noise, characterized by: The pavement structure is laid above the beam and the abutment. The pavement structure consists of five layers, which are, from bottom to top, a stabilization layer, a waterproof crack suppression layer, a sliding layer, a middle surface layer, and an upper surface layer. Each layer of the pavement structure is a continuous pavement layer with no expansion joints on the surface. A gap is provided between the beam and the abutment, and a leak-proof net is provided at one-third of the depth of the gap. A first circular arc is provided between the gap and the abutment, the center of the first circular arc is on the same horizontal line as the anti-leakage net, the central angle of the first circular arc is 90 degrees, and the radius of the first circular arc is one third of the depth of the gap; A second arc is provided between the gap and the beam body, the center of the second arc is on the same horizontal line as the anti-leakage net, and the radius of the second arc is two-thirds of the depth of the gap.

2. The pavement structure of a bridge deck without expansion joints and with low noise according to claim 1 is characterized in that: The length of the beam body does not exceed 100m, and the thickness of the beam body is 15-20cm; the length of the abutment is 5m, and the thickness of the abutment is the same as the thickness of the beam body; the width of the gap is 5-20mm, and the depth of the gap is the same as the thickness of the beam body.

3. The pavement structure of a bridge deck without expansion joints and with low noise according to claim 2, characterized in that: A plurality of circular holes are provided on the leak-proof net, and the diameter of the circular holes is 1-2 mm.

4. The pavement structure of a bridge deck without expansion joints and with low noise according to claim 3 is characterized in that: The stabilizing layer is a high-strength and high-toughness asphalt mortar layer with a thickness of 1-3 cm, a dynamic stability of 50,000 times / mm at 60°C, and a low-temperature bending failure strain of 5000 με at -10°C.

5. The pavement structure of a bridge deck without expansion joints and with low noise according to claim 4 is characterized in that: The waterproof crack inhibition layer is paved with asphalt or polymer waterproof membrane with a thickness of 2-5 mm, a high-temperature shear resistance of greater than 2.5 N / mm at 60°C, and a low-temperature crack resistance of greater than 8 MPa at -20°C.

6. The pavement structure of a bridge deck without expansion joints and with low noise according to claim 5, characterized in that: The sliding layer is composed of three layers, which are, from bottom to top, the first ball layer, the bearing plate and the second ball layer; the balls in the first ball layer and the second ball layer are any one of river sand, corundum and steel balls, and their particle size is a single particle size within the range of 1.18-2.36mm. The thickness of the first ball layer and the second ball layer is 1-5mm; the bearing plate is a steel plate with a thickness of 5-10mm.

7. The pavement structure of a bridge deck without expansion joints and with low noise according to claim 6, characterized in that: The middle surface layer is paved with asphalt mixture and has a thickness of 5-7 cm; the nominal maximum aggregate particle size of the asphalt mixture is any one of 13.2 mm, 16 mm, 20 mm, and 25 mm, and the type of the asphalt mixture is asphalt concrete AC, mastic asphalt crushed stone mixture SMA, or large-void asphalt mixture PAC.

8. The pavement structure of a bridge deck without expansion joints and with low noise according to claim 7, characterized in that: The upper layer is paved with large-void asphalt mixture or high-damping asphalt mixture, and its thickness is 3-5 cm; the void ratio of the large-void asphalt mixture is greater than 20%, and the peak sound absorption coefficient is greater than 0.8; the damping ratio of the high-damping asphalt mixture is greater than 40%.

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