Thermal insulation type steel bridge asphalt concrete composite pavement layer structure

Abstract

The utility model belongs to the field of highway bridge engineering, and relates to a heat insulation type steel bridge asphalt concrete composite pavement structure. The utility model discloses can increase the connection with asphalt concrete pavement layer through the rib design of the outer surface of pipeline, effectively enhances structural stability, avoids interlayer slip, further adopts the double-layer asphalt concrete pavement structure of lower SMA-16 plus upper SMA-10, and the heat insulation waterproof layer with pipeline is matched, not only through the hierarchical grading that strengthens the shear resistance, the skid resistance of asphalt concrete pavement layer, but also relies on the high temperature resistance, the toughness and the rib design of heat insulation waterproof layer material and improves interlayer connection and waterproof effect, in addition, through the air heat insulation layer formed by laying pipeline, cooperate the low thermal conductivity and excellent high temperature resistance of dense thin layer, through the S type water flow path formed by the water retaining tank and the pipeline, make this scheme have all-season self-adapting temperature control adjustment function.

Description

Technical Field

[0001] This utility model belongs to the technical field of highway bridge engineering, specifically relating to a heat-insulating steel bridge deck asphalt concrete composite pavement structure. Background Technology

[0002] Steel structure bridges have a significant advantage in terms of light weight, making them highly adaptable to assembly and construction. Their components can be prefabricated in factories to achieve standardized production, which greatly improves on-site assembly efficiency. At the same time, their lightweight characteristics make hoisting operations more convenient, making them particularly suitable for the construction of long-span bridges and high-gradient overpasses. Therefore, they are widely used in the engineering field.

[0003] As an important component of steel structure bridges, the performance of steel bridge deck pavement directly affects the bridge's operational safety and service life. However, it is prone to various defects under different environmental conditions, as follows: In high-temperature environments, the asphalt concrete pavement layer of steel bridge decks is exposed to direct sunlight, resulting in a surface temperature far exceeding that of the atmosphere. This leads to a significant decrease in the stiffness and strength of the asphalt mixture. Due to the significant difference in elastic modulus between the steel bridge deck and the pavement layer, permanent deformation can easily occur under heavy vehicle loads and alternating day-night temperature stress, causing problems such as rutting, slippage, and swelling. This not only reduces driving comfort but also increases the risk of traffic accidents due to uneven road surfaces, threatening the safe operation of the bridge.

[0004] In low-temperature environments, asphalt mixtures become brittle and their resistance to deformation decreases. Furthermore, the difference in shrinkage properties between the steel bridge deck and the pavement layer generates significant temperature stress, leading to cracking of the pavement layer. Simultaneously, low temperatures cause a sharp drop in interlayer bond strength, resulting in delamination between the pavement layer and the steel deck. Freeze-thaw cycles further widen cracks, exacerbate internal loosening, and ultimately form potholes, compromising the integrity of the pavement layer and shortening its service life. The use of de-icing agents in winter also causes corrosion and environmental pollution to the steel bridge system.

[0005] Under normal temperature conditions, the long-term repeated action of vehicle loads leads to the accumulation of fatigue stress in the pavement layer. Furthermore, if rainwater seeps in and is not drained in time, it can cause water damage, manifested as asphalt film peeling and aggregate loosening. The superposition of fatigue damage and water damage will gradually weaken the structural performance of the pavement layer, exacerbating the occurrence and development of defects.

[0006] To address the aforementioned defects in steel bridge deck pavement, relevant technologies have been applied, but all have significant limitations: ultra-high performance concrete is difficult to promote on a large scale due to its high material cost and complex construction process; the ERS system lacks stability in high-temperature environments and is prone to deformation defects; ECO modified polyurethane concrete not only has controversial high-temperature durability, but its low-temperature crack resistance and adhesion durability to steel bridge deck are also poor.

[0007] Therefore, there is an urgent need for a technical solution that can adapt to temperature changes throughout the entire life cycle and effectively solve the problems of steel bridge deck pavement defects under different environments, so as to improve the service life of the pavement layer.

[0008] In view of the above, this utility model is hereby proposed. Summary of the Invention

[0009] The purpose of this invention is to overcome the shortcomings of the prior art and provide a heat-insulated steel bridge deck asphalt concrete composite pavement structure. Based on a comprehensive heat insulation and waterproof design concept, it addresses the insufficient deformation resistance of asphalt concrete pavement layers under high-temperature environments by using a heat-insulating and waterproof layer with transverse semi-cylindrical channels connected to the asphalt concrete to achieve active cooling and deformation synergy for the pavement layer. Addressing the problems of poor interlayer bonding durability and insufficient crack resistance under low-temperature conditions, it enhances interlayer bonding stability and alleviates temperature stress through the high toughness of polyamide-imide materials and a warm water circulation system. Addressing the problem of fatigue damage and water damage superimposed at room temperature, it utilizes the natural ventilation efficiency of the channels to reduce moisture accumulation and buffer the load fatigue effect, forming a temperature-adaptive composite pavement system throughout its entire life cycle, thereby improving the service life of the pavement layer.

[0010] To achieve the above objectives, the present invention provides the following technical solution: This utility model provides a heat-insulating steel bridge deck asphalt concrete composite pavement structure, including a steel bridge deck layer, on which a heat-insulating and waterproof layer and an asphalt concrete pavement layer are laid sequentially; the heat-insulating and waterproof layer includes a dense thin layer and multiple pipes fixed on the dense thin layer; multiple water-retaining grooves are provided on both sides of the steel bridge deck layer and on the dense thin layer, each water-retaining groove is connected to its corresponding pipe, and the water-retaining grooves on opposite sides of the steel bridge deck layer are arranged in a corresponding and staggered manner to adapt to the S-shaped flow of water; each water-retaining groove is provided with an overflow port, and the overflow port is connected to the bridge drainage system.

[0011] Specifically, the lateral width of the dense thin layer is greater than the lateral width of the pipe to facilitate the installation of a water-blocking groove.

[0012] Specifically, adjacent water-blocking channels share a single water-blocking plate. Each water-blocking channel has a depth of 45-55mm, a width of 22-28mm, and a thickness of 2mm. The distance between adjacent water-blocking plates is 1m. The height of each water-blocking plate is 45-55mm, its length is 22-28mm, and its thickness is 2mm. Both the water-blocking channels and the water-blocking plates are made of stainless steel and are welded together. Both the water-blocking channels and the water-blocking plates are sealed with a dense thin layer, which allows for the rapid drainage of infiltrated rainwater and return water from the water-cooling system.

[0013] Specifically, the pipe has a semi-circular cross-sectional shape, is integrally formed with a dense thin layer, and its top is embedded in the asphalt concrete pavement layer.

[0014] Specifically, the pipe has multiple ribs evenly distributed along its axial direction and outer periphery, and the ribs are embedded in the asphalt concrete pavement layer.

[0015] Furthermore, the height of the rib is 4~6mm and the width is 0.8~1.2mm.

[0016] Specifically, the dense thin layer is made of polyamide-imide (PAI) high-strength engineering plastic, which has high temperature resistance and toughness; the thickness of the dense thin layer is 2.5~3.5mm; the thickness of the pipe is 2.5~3.5mm; and the diameter of the pipe is 14~20mm.

[0017] Specifically, the pipe is made of one of the following materials: polyamide-imide (PAI), commonly used engineering metals, or ceramics.

[0018] Specifically, the pipe is arranged horizontally or inclined relative to the direction of travel. When the pipe is inclined, the angle of the pipe relative to the direction of travel can be any angle that satisfies the S-shaped flow of water. The distance between adjacent pipes is 10±2mm to form an air insulation layer to reduce heat conduction.

[0019] Specifically, the asphalt concrete pavement layer includes an SMA-16 layer and an SMA-10 layer laid on top of the SMA-16 layer.

[0020] Furthermore, the thickness of the SMA-16 layer is 50~80mm, and the thickness of the SMA-10 layer is 30~40mm.

[0021] Specifically, the SMA-16 layer uses asphalt mastic aggregate with a nominal maximum particle size of 16mm. By weight, the asphalt mastic aggregate has the following pass rates: 100% for 19mm sieves, 90%-100% for 16mm sieves, 65%-85% for 13.2mm sieves, 30%-50% for 9.5mm sieves, 20%-34% for 4.75mm sieves, 15%-26% for 2.36mm sieves, 14%-24% for 1.18mm sieves, 12%-20% for 0.6mm sieves, 10%-16% for 0.3mm sieves, 9%-15% for 0.15mm sieves, and 8%-12% for 0.075mm sieves. The SMA-10 layer uses asphalt mastic aggregate with a nominal maximum particle size of 9.5mm. By weight, the passing rates are asphalt mastic aggregate with 100% pass rate for 13.2mm sieves, 90%-100% pass rate for 9.5mm sieves, 20%-32% pass rate for 4.75mm sieves, 15%-26% pass rate for 2.36mm sieves, 14%-24% pass rate for 1.18mm sieves, 12%-20% pass rate for 0.6mm sieves, 10%-16% pass rate for 0.3mm sieves, 9%-15% pass rate for 0.15mm sieves, and 8%-12% pass rate for 0.075mm sieves.

[0022] Specifically, a concrete leveling layer is laid on the steel bridge surface, and multiple fixing parts for fixing the heat insulation and waterproof layer are uniformly fixed on the concrete leveling layer. One end of the fixing part penetrates the dense thin layer and is embedded in the asphalt concrete pavement layer. The fixing part is one of rivets, bolts, and nails.

[0023] Compared with the prior art, the technical solution provided by this utility model has the following beneficial effects: Structurally, this invention utilizes a ribbed design on the outer surface of the pipe to increase the connection with the asphalt concrete pavement layer, effectively enhancing structural stability and preventing interlayer slippage. Simultaneously, the hollow structure of the pipe buffers the vibration stress generated by vehicle loads. In terms of material selection, a double-layer asphalt concrete pavement structure is adopted, consisting of a lower layer of SMA-16 and an upper layer of SMA-10, combined with a heat-insulating and waterproof layer incorporating the pipe. This layered gradation strengthens the shear and anti-slip properties of the asphalt concrete pavement layer, while the high-temperature resistance, toughness, and ribbed design of the heat-insulating and waterproof layer enhance the interlayer connection and waterproofing effect. Furthermore, the air insulation layer formed by the pipe, combined with the low thermal conductivity and excellent high-temperature resistance of the dense, thin layer, and the S-shaped water flow path formed by the water-blocking channel and the pipe, enables this invention to have an all-season adaptive temperature control function, even in high-temperature conditions. During seasonal periods (daily high temperatures above 35°C), the water used for cooling flows in an S-shape through the pipes of the heat-insulating and waterproof layer, effectively insulating and cooling the asphalt concrete pavement. During cold seasons (daily low temperatures below 0°C), warm or hot water is injected through the water-retaining channels, which can inhibit surface icing and low-temperature fatigue cracking of the asphalt concrete pavement. During transitional seasons, natural ventilation through the pipes can reduce the temperature gradient of the asphalt concrete pavement, reducing temperature stress and temperature fatigue damage within the pavement. This not only significantly reduces high-temperature defects such as rutting, shoving, and shoving, as well as the risk of icing on the pavement at low temperatures, thus extending the service life of the asphalt concrete pavement, but also greatly reduces the use of de-icing agents, minimizing their corrosion of the steel bridge system and environmental pollution. Furthermore, the water from the drainage channels can be used for municipal landscaping. Attached Figure Description

[0024] The accompanying drawings are incorporated in and form part of this specification, and together with the description, serve to explain the principles of this invention.

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a three-dimensional structural schematic diagram of the present invention; Figure 2 This is a top view of the present invention; Figure 3 for Figure 2 Sectional view along axis AA; Figure 4 for Figure 2 BB-direction sectional view; Figure 5 This is a three-dimensional structural diagram of the heat insulation and waterproof layer of this utility model; Figure 6 for Figure 5 The main view.

[0027] Among them: 1 is the steel bridge deck layer; 2 is the dense thin layer; 3 is the pavement layer baffle; 4 is the asphalt concrete pavement layer; 41 is the SMA-16 layer; 42 is the SMA-10 layer; 5 is the pipe; 6 is the rib; 7 is the water-retaining groove; 8 is the water-retaining plate; 9 is the overflow outlet. Detailed Implementation

[0028] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. The embodiments described below do not represent all embodiments consistent with this invention. Rather, they are merely examples consistent with some aspects of this invention as detailed in the appended claims.

[0029] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Example

[0030] See Figure 1-6As shown, this utility model provides a heat-insulating steel bridge deck asphalt concrete composite pavement structure, including a steel bridge deck layer 1, on which a heat-insulating and waterproof layer and an asphalt concrete pavement layer 4 are sequentially laid; the heat-insulating and waterproof layer includes a dense thin layer 2 and multiple pipes 5 fixed on the dense thin layer 2; multiple water-retaining grooves 7 are provided on both sides of the steel bridge deck layer 1 and on the dense thin layer 2, each water-retaining groove 7 is connected to its corresponding pipe 5, and the water-retaining grooves 7 on opposite sides of the steel bridge deck layer 1 are correspondingly and staggered to adapt to the S-shaped flow of water, see [reference]. Figure 2 The blue lines in the diagram indicate that the direction of water flow shown does not represent the actual direction of water flow and is for illustrative purposes only. Each of the water-blocking channels 7 is equipped with an overflow port 9, which is connected to the bridge drainage system.

[0031] Specifically, the transverse width of the dense thin layer 2 is greater than the transverse width of the pipe 5, so as to facilitate the installation of the water-blocking groove 7.

[0032] Specifically, adjacent water-blocking channels 7 share a single water-blocking plate 8. Each water-blocking channel 7 has a depth of 50mm (a suitable size can be selected based on actual usage, such as 45mm or 55mm), a width of 30mm (a suitable size can be selected based on actual usage, such as 22mm or 30mm), and a thickness of 2mm. The distance between adjacent water-blocking plates 8 is 1m. The height of each water-blocking plate 8 is 50mm (a suitable size can be selected based on actual usage, such as 45mm or 55mm), a length of 30mm (a suitable size can be selected based on actual usage, such as 22mm or 30mm), and a thickness of 2mm. Both the water-blocking channels 7 and the water-blocking plates 8 are made of stainless steel and are welded together. Both the water-blocking channels 7 and the water-blocking plates 8 are sealed to a dense thin layer 2, allowing for rapid drainage of infiltrated rainwater and return water from the water storage device.

[0033] Specifically, the cross-sectional shape of the pipe 5 is semi-circular, and the top of the pipe is embedded in the asphalt concrete pavement layer 4.

[0034] Specifically, the pipe 5 has three ribs 6 evenly distributed along its axial direction and outer periphery. The ribs 6 are embedded in the asphalt concrete pavement layer 4, that is, embedded in the SMA-16 layer 41.

[0035] Furthermore, the rib 6 has a height of 5mm (the appropriate size can be selected according to the actual use, such as 0.8mm or 1.2mm) and a width of 1mm (the appropriate size can be selected according to the actual use, such as 4mm or 6mm).

[0036] Specifically, the dense thin layer 2 is made of polyamide-imide (PAI) high-strength engineering plastic, which has high temperature resistance and toughness, and a thickness of 3mm (the appropriate size can be selected according to the actual use, such as 2.5mm or 3.5mm); the pipe 5 has a thickness of 3mm (the appropriate size can be selected according to the actual use, such as 2.5mm or 3.5mm), and the diameter of the pipe 5 is 17mm (the appropriate size can be selected according to the actual use, such as 14mm or 20mm).

[0037] Specifically, the material of the pipe 5 is one of polyamide-imide (PAI), commonly used engineering metal materials, or ceramic materials, and the appropriate material can be selected according to production needs; the pipe 5 is integrally formed with the dense thin layer 2.

[0038] Specifically, the pipe 5 is arranged laterally relative to the direction of travel; the distance between adjacent pipes 5 is 10mm, forming an air insulation layer to reduce heat conduction.

[0039] Specifically, the asphalt concrete pavement layer 4 includes an SMA-16 layer 41 and an SMA-10 layer 42 laid on the SMA-16 layer 41.

[0040] Furthermore, the thickness of the SMA-16 layer 41 is 60mm (a suitable size can be selected according to the actual use, such as 50mm or 80mm), and the thickness of the SMA-10 layer 42 is 50mm (a suitable size can be selected according to the actual use, such as 30mm or 40mm).

[0041] Specifically, a concrete leveling layer is laid on the steel bridge surface layer 1. The concrete leveling layer is uniformly fixed with multiple fixing parts for fixing the heat insulation and waterproof layer. One end of the fixing part penetrates the dense thin layer 2 and is embedded in the asphalt concrete pavement layer 4. The fixing part is one of rivets, bolts, or nails, and the appropriate material can be selected according to production needs.

[0042] Specifically, the water-blocking groove 7 at the bridge expansion joint is connected by a rubber U-shaped pipe to facilitate the smooth flow of water.

[0043] Specifically, the asphalt concrete pavement layer 4 is provided with pavement layer baffles 3 on both sides. The pavement layer baffles 3 are sealed to the dense thin layer 2. Each pavement layer baffle 3 is provided with a hole that communicates with the pipe 5 so that the pipe 5 can communicate with the water blocking channel 7.

[0044] This embodiment also provides an operation method for a heat-insulated steel bridge deck asphalt concrete composite pavement structure, as detailed below: First, a water storage device is installed next to the bridge. The water storage device can also heat water to 20~40℃ in winter. During the high-temperature season (when the daily maximum temperature exceeds 35℃), water used for cooling enters the water-retaining trough 7 on the side of the bridge from the water storage device, and flows through the pipe 5 of the heat insulation and waterproof layer in an S-shaped flow path to insulate and cool the asphalt concrete pavement layer 4, effectively suppressing the shoving, bulging and other defects of the asphalt concrete pavement layer 4 on the steel bridge deck during the high-temperature season. During the low-temperature season (daily minimum temperature below 0℃), the water storage device heats the water to 20℃ and passes it through the water-blocking trough 7, and then through the heat-insulating and waterproof pipe 5 in an S-shaped flow path to inhibit the freezing of the surface of the asphalt concrete pavement layer 4, improve driving safety, and also greatly reduce the use of de-icing agents, thereby reducing the corrosion of the steel bridge system and environmental pollution caused by de-icing agents. In other seasons, due to factors such as diurnal temperature variations, changes in solar radiation intensity, and fluctuations in ambient temperature, the asphalt concrete pavement layer 4 experiences periodic temperature changes. These periodic temperature changes cause repeated stress and strain in the asphalt concrete pavement layer 4 material due to thermal expansion and contraction. When this stress and strain exceed the material's fatigue limit, it triggers temperature fatigue damage, specifically manifested as the gradual appearance of microcracks within the asphalt concrete pavement layer 4. Over time, these microcracks expand and connect, ultimately leading to structural damage to the asphalt concrete pavement layer 4 and significantly shortening its service life. In contrast, the horizontally arranged pipe 5 in this invention forms an effective natural ventilation path in other seasons, allowing air to circulate freely within the channel. The flow can promptly remove the heat accumulated in the asphalt concrete pavement layer 4 due to changes in ambient temperature, and at the same time, it can accelerate the temperature recovery rate of the asphalt concrete pavement layer 4 in low-temperature environments, thereby significantly reducing the internal temperature gradient of the asphalt concrete pavement layer 4. The reduction in temperature gradient makes the temperature change at different depths of the asphalt concrete pavement layer 4 more uniform, reducing the additional stress caused by excessive temperature differences between layers of material, and thus reducing the amplitude of periodic stress and strain borne by the material. In this way, the transversely arranged pipes 5 can effectively alleviate the temperature fatigue damage process of the asphalt concrete pavement layer 4 material, delay the generation and propagation of microcracks, and ultimately achieve the goal of extending the service life of the asphalt concrete pavement layer 4.

[0045] Example 2 The difference between this embodiment and embodiment 1 is that the pipe 5 is inclined; the angle of the pipe 5 relative to the direction of travel is any angle that satisfies the S-shaped flow of water.

[0046] The above description is merely a specific embodiment of this utility model, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this utility model.

[0047] It should be understood that this utility model is not limited to the content already described above, and various modifications and changes can be made without departing from its scope. The scope of this utility model is limited only by the appended claims.

Claims

1. A heat-insulating steel bridge deck asphalt concrete composite pavement structure, characterized in that, The steel bridge deck includes a steel bridge surface layer (1), on which a heat insulation and waterproof layer and an asphalt concrete pavement layer (4) are laid in sequence. The heat insulation and waterproof layer includes a dense thin layer (2) and multiple pipes (5) fixed on the dense thin layer (2). Multiple water-blocking grooves (7) are provided on both sides of the steel bridge surface layer (1) and on the dense thin layer (2). Each water-blocking groove (7) is connected to its corresponding pipe (5). The water-blocking grooves (7) on opposite sides of the steel bridge surface layer (1) are arranged in a corresponding and staggered manner to adapt to the S-shaped flow of water.

2. The thermally insulated steel bridge deck asphalt concrete composite pavement structure according to claim 1, characterized in that, The cross-sectional shape of the pipe (5) is semi-circular. The pipe (5) is integrally formed with the dense thin layer (2). The top of the pipe (5) is embedded in the asphalt concrete pavement layer (4).

3. The thermally insulated steel bridge deck asphalt concrete composite pavement structure according to claim 1, characterized in that, The pipe (5) has multiple ribs (6) evenly distributed along its axial direction and outer periphery, and the ribs (6) are embedded in the asphalt concrete pavement layer (4).

4. The thermally insulated steel bridge deck asphalt concrete composite pavement structure according to claim 3, characterized in that, The rib (6) has a height of 4~6mm and a width of 0.8~1.2mm.

5. The thermally insulated steel bridge deck asphalt concrete composite pavement structure according to claim 1, characterized in that, The asphalt concrete pavement layer (4) includes an SMA-16 layer (41) and an SMA-10 layer (42) laid on the SMA-16 layer (41).

6. The thermally insulated steel bridge deck asphalt concrete composite pavement structure according to claim 5, characterized in that, The thickness of the SMA-16 layer (41) is 50~80mm, and the thickness of the SMA-10 layer (42) is 30~40mm.

7. The thermally insulated steel bridge deck asphalt concrete composite pavement structure according to claim 1, characterized in that, The thickness of the dense thin layer (2) is 2.5~3.5mm.

8. The thermally insulated steel bridge deck asphalt concrete composite pavement structure according to claim 1, characterized in that, The thickness of the pipe (5) is 2.5~3.5mm and the diameter is 14~20mm.

9. The thermally insulated steel bridge deck asphalt concrete composite pavement structure according to claim 1, characterized in that, The steel bridge surface layer (1) is uniformly fixed with multiple fixing parts for fixing the heat insulation and waterproof layer, and one end of the fixing part penetrates the dense thin layer (2).

10. The thermally insulated steel bridge deck asphalt concrete composite pavement structure according to claim 1, characterized in that, The pipe (5) is set laterally or at an angle relative to the direction of travel.

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