Recycled pavement structure-material integrated design method based on road performance balance

Abstract

The application discloses a kind of based on road performance balance's recycling pavement structure-material integrated design method, comprising the following steps: actual road surface layer material asphalt mixture is milled down and is reprocessed to obtain recycling asphalt mixture, and it is used as the surface layer material of recycling pavement;According to design requirement, recycling inorganic mixture is prepared, and it is used as the base material of recycling pavement;According to design requirement, recycling pavement is paved in construction site, and the road performance of each layer is monitored through monitoring unit;According to design requirement, recycling pavement test piece is laid in laboratory, and the road performance of each test piece is monitored through monitoring unit;The road performance of each layer bottom monitored in construction site is compared with the road performance of each test piece monitored in laboratory one by one, and then the rationality of recycling pavement structure-material integrated design based on road performance balance is verified.The application can effectively integrate recycling materials such as construction waste, and optimize the structural design of recycling pavement.

Description

Technical Field

[0001] This invention belongs to the field of road engineering technology, specifically relating to an integrated design method for recycled pavement structure and materials based on road performance balance. Background Technology

[0002] In recent years, with the continuous development of global transportation infrastructure construction, the design and construction methods of pavement structures have also been constantly updated and optimized. Foreign countries have relatively mature technologies for the application of recycled pavement materials; for example, the United States and some European countries widely use recycled asphalt pavement materials (RAP) and recycled concrete pavement materials (RCP) for recycling. Domestically, China is also actively exploring and promoting recycled pavement technology, especially in large-scale infrastructure construction and urbanization processes. The extensive application of recycled materials not only reduces resource waste but also effectively reduces environmental pollution.

[0003] Currently, the technology of recycling construction waste in road design is receiving increasing attention. Several research institutions and universities have launched related research projects dedicated to transforming construction waste into high-quality recycled materials for road construction. For example, some studies have explored using recycled concrete aggregate (RCA) and recycled brick aggregate (RBA) as base materials for pavements, improving the road performance and durability of recycled materials by optimizing mix proportions and refining construction processes. However, most existing research focuses on the recycling of single surface layer or base layer materials, lacking systematic research on the integrated design of recycled pavement structures and materials that incorporate construction waste, including both surface and base layers.

[0004] Furthermore, the development of pavement sensor technology has provided new means for monitoring and evaluating pavement performance, facilitating timely understanding of pavement operating conditions and enabling corresponding maintenance decisions. Some advanced countries abroad have widely applied sensors in the construction of intelligent road systems, achieving full life-cycle monitoring and management of pavements through integrated sensor networks. Domestically, the application of sensor technology in pavement engineering is also gradually gaining attention, with various sensors being installed on pilot projects on some highways and urban roads, achieving good monitoring results.

[0005] Nevertheless, there is currently no mature method for integrated structure-material design of recycled pavements containing construction waste, nor is there a systematic study on sensor performance monitoring of the entire recycled pavement structure. Existing research in this field mainly focuses on the recycling of single surface layer materials or single base layer materials and the monitoring of their local performance, which cannot comprehensively cover the performance evaluation of the overall pavement structure. Therefore, developing an integrated structure-material design method for recycled pavements based on road performance balance is an urgent need in this technical field.

[0006] The invention patent application with publication number CN112414460A discloses a measurement system for intelligently acquiring the dynamic mechanical response of asphalt pavement, including a sensor group, a power supply, and a data collector. The sensor group is located at the bottom of the asphalt pavement, with each sensor arranged at a set interval and electrically connected to the power supply and the data collector. The sensor group includes asphalt strain gauges, earth pressure gauges, vertical strain gauges, and multi-point displacement gauges. The asphalt strain gauges, earth pressure gauges, and vertical strain gauges are all located at the wheel tracks of vehicles on the driving lane, while the multi-point displacement gauges are located at the hard shoulder. Eight asphalt strain gauges are configured, and any two asphalt strain gauges are paired to form four asphalt strain gauge measurement units, which enclose a quadrilateral area. One earth pressure gauge is configured and located inside the quadrilateral area, and eight vertical strain gauges are configured and located outside the quadrilateral area. The two asphalt strain gauges in each asphalt strain gauge measurement unit are arranged perpendicularly to each other. One asphalt strain gauge measures the tensile strain at the bottom of the asphalt pavement in the driving direction, and the other asphalt strain gauge measures the tensile strain at the bottom of the asphalt pavement in the driving lane width direction. This technical solution is only applicable to ordinary roads and can only collect dynamic mechanical data of the asphalt surface layer of ordinary roads. It is not applicable to recycled roads, and it is even more impossible to collect dynamic mechanical data of the overall structure of recycled roads (including the surface layer and the base layer). Summary of the Invention

[0007] To address the problems existing in the prior art, this invention provides an integrated design method for recycled pavement structure and materials based on road performance balance. The design method includes the following steps in sequence: Step 1: Mill off the asphalt mixture from the actual road surface material and reprocess it to obtain recycled asphalt mixture. Use the obtained recycled asphalt mixture as the surface material of the recycled pavement. The surface layer of the recycled pavement includes a bottom layer, a middle layer, and a top layer. Step 2: Prepare recycled inorganic mixture according to design requirements, and use the prepared recycled inorganic mixture as the base material of recycled pavement. The base of recycled pavement includes subbase, lower base and upper base. Step 3: Prepare several monitoring devices and check them to ensure that each monitoring device can be used normally; Step 4: At the construction site, the recycled pavement is laid according to the design requirements. First, the subgrade is leveled. Then, from bottom to top, the subbase, lower base course, upper base course, lower layer, intermediate layer, and upper layer are laid on top of the subbase. During the paving process, each layer is compacted using a road roller. Simultaneously, during the paving process, the first, second, third, fourth, and fifth monitoring units are placed on the upper surface of the subbase and the upper surfaces of the compacted subbase, lower base course, upper base course, and lower layer, respectively. Finally, vehicles are allowed to travel on the overall recycled pavement, entering from one end and exiting from the other. During vehicle travel, the first, second, third, fourth, and fifth monitoring units monitor various road performance characteristics of the subbase, lower base course, upper base course, lower layer, and intermediate layer, respectively, and feed the monitoring results back to the monitoring system. Step 5: In the laboratory, lay the recycled pavement test specimens according to the design requirements. First, lay the subbase test specimen. On the test platform, lay the subgrade, subbase monitoring unit, and subbase layer sequentially from bottom to top, and compact it using static pressure. After compaction, conduct an accelerated loading test. During the accelerated loading test, the subbase monitoring unit monitors various pavement performance characteristics of the subbase layer. Next, lay the lower base test specimen. On the test platform, lay the subbase, lower base monitoring unit, and lower base layer sequentially from bottom to top, and compact it using static pressure. After compaction, conduct an accelerated loading test. During the accelerated loading test, the lower base monitoring unit monitors various pavement performance characteristics of the lower base layer. Finally, lay the upper base test specimen. On the test platform, lay the lower base layer, upper base monitoring unit, and lower base layer sequentially from bottom to top. The upper base course was compacted using static pressure, followed by an accelerated loading test. During the accelerated loading test, the upper base course monitoring unit monitored various road performance characteristics of the bottom layer of the upper base course. Next, the lower base course test specimen was laid. On the test platform, the upper base course, lower base course monitoring unit, and lower base course were laid sequentially from bottom to top, and compacted using static pressure. After compaction, an accelerated loading test was conducted, during which the lower base course monitoring unit monitored various road performance characteristics of the bottom layer of the lower base course. Finally, the middle layer test specimen was laid. On the test platform, the lower base course, middle layer monitoring unit, and middle layer were laid sequentially from bottom to top, and compacted using static pressure. After compaction, an accelerated loading test was conducted, during which the middle layer monitoring unit monitored various road performance characteristics of the bottom layer of the middle layer. Step Six: Compare the various road performance parameters of the subbase, lower base, upper base, lower layer, and intermediate layer bottom obtained from on-site monitoring with the various road performance parameters of the subbase, lower base, upper base, lower layer, and intermediate layer bottom obtained from laboratory monitoring. Verify the rationality of the integrated design of recycled pavement structure and materials based on road performance balance based on the comparison results. In step six, if the average deviation of each pavement performance item obtained from on-site monitoring is no greater than 3% of the average deviation of each pavement performance item obtained from laboratory monitoring, it indicates that the integrated design of recycled pavement structure and materials based on pavement performance balance is reasonable. If the average deviation of a certain pavement performance item obtained from on-site monitoring is greater than 3% of the corresponding average deviation of the pavement performance item obtained from laboratory monitoring, it indicates that the integrated design of recycled pavement structure and materials based on pavement performance balance is unreasonable. For paving layers with unreasonable designs, their thickness needs to be adjusted.

[0008] Preferably, in step one, the method for preparing the recycled asphalt mixture is as follows: first, the asphalt mixture of the actual road surface material is milled and recycled; then, the recycled asphalt mixture is subjected to secondary crushing and secondary screening in sequence to obtain recycled aggregate; finally, the recycled aggregate, new aggregate, mineral powder and emulsified asphalt are put into a mixer and stirred to obtain the recycled asphalt mixture.

[0009] The mass percentage of each substance in the recycled asphalt mixture is as follows: recycled aggregate accounts for 50-60 wt%, new aggregate accounts for 20-30 wt%, mineral powder accounts for 8-15 wt%, and emulsified asphalt accounts for 10-15 wt%; the mixing temperature is 175℃ and the mixing time is 90 s.

[0010] In any of the above schemes, it is preferred that, in step two, the mass percentage of each substance in the recycled inorganic mixture is as follows: cement accounts for 6-7 wt%, recycled aggregate from high-strength brick-concrete construction waste accounts for 87-89 wt%, and water accounts for 5-6 wt%. The substances are placed in a mixer and stirred at room temperature, at a stirring speed of 45-50 r / min, and for a stirring time of 1-3 min.

[0011] The cement is PO 32.5 slag silicate cement; the high-quality brick-concrete construction waste recycled aggregate is construction waste generated from the demolition of brick-concrete buildings, with a brick-concrete content of 60-80 wt%, wherein the aggregate with particle sizes of 20-31.5 mm, 10-20 mm, 5-10 mm, and 0-5 mm accounts for 10-15%, 20-25%, 25-30%, and 30-35% of the mass of the high-quality brick-concrete construction waste recycled aggregate, respectively.

[0012] In any of the above schemes, it is preferred that, in step two, the mass percentage of each substance in the recycled inorganic mixture is as follows: lime accounts for 4-5 wt%, fly ash accounts for 9-10 wt%, recycled aggregate from high-strength brick-concrete construction waste accounts for 81-82 wt%, and water accounts for 5-6 wt%. The substances are placed in a mixer and stirred at room temperature, at a stirring speed of 45-50 r / min, and for 1-3 min.

[0013] The lime is magnesian quicklime, containing 60-70% effective CaO, 5-6% effective MgO, and the remainder being impurities; the fly ash contains 30-40% Al2O3, 4-5% Fe2O3, and 50-60% SiO2, with the remainder being impurities; the fly ash has a loss on ignition of 7-8% and a specific surface area of ​​450-500 m². 2 / kg; the high-quality brick-concrete construction waste recycled aggregate is construction waste generated from the demolition of brick-concrete buildings, with a brick-concrete content of 60-80wt%, wherein the aggregate with particle sizes of 20-31.5mm, 10-20mm, 5-10mm, and 0-5mm accounts for 10-15%, 20-25%, 25-30%, and 30-35% of the mass of the high-quality brick-concrete construction waste recycled aggregate, respectively. In this invention, effective CaO and effective MgO are CaO and MgO that can play a role.

[0014] In any of the above schemes, it is preferred that, in step three, the monitoring device includes an asphalt strain gauge, a concrete strain gauge, a vertical strain gauge, an earth pressure gauge, a temperature sensor, and a humidity sensor.

[0015] In any of the above schemes, preferably, in step four, a first monitoring unit is arranged on the upper surface of the subgrade to test various road performance characteristics of the subbase layer. This unit includes fourteen concrete strain gauges, two earth pressure gauges, seven humidity sensors, and one temperature sensor. In the driving lane area, the fourteen concrete strain gauges are arranged in a rectangle, with three strain gauges at each of the four vertices. Two strain gauges are arranged perpendicularly to each other on the horizontal plane, and one strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined strain gauge and the horizontal strain gauge is 20-30°. A humidity sensor is placed in the angled area between the inclined and vertical strain gauges. A concrete strain gauge is inclinedly placed at the midpoint of each of the two long sides of the rectangle, with an angle of 20-30° between the inclined concrete strain gauge and the long side of the rectangle. A humidity sensor is placed in the area between the inclined concrete strain gauge and the wide side of the rectangle. The midpoint of the two long sides of the rectangle divides the rectangle into two equal regions, left and right. An earth pressure gauge is placed at the center of each region. The horizontal distance between the rectangle and the edge of the driving lane is 60cm. The length of the rectangle is 100cm and the width of the rectangle is 60cm. In the hard shoulder area, a humidity sensor and a temperature sensor are arranged sequentially from left to right. The horizontal distance between the humidity sensor and the temperature sensor is 60cm, and the horizontal distance between the temperature sensor and the rectangle is 10cm.

[0016] A second monitoring unit is arranged on the upper surface of the compacted subbase layer to test various road performance characteristics of the subbase layer. The horizontal distance between the second and first monitoring units is 10 cm. This unit includes fourteen concrete strain gauges, two earth pressure gauges, seven humidity sensors, and one temperature sensor. In the driveway area, the fourteen concrete strain gauges are arranged in a rectangle, with three strain gauges at each of the four vertices. Two strain gauges are arranged perpendicularly to each other on the horizontal plane, and one strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined strain gauge and the horizontal strain gauge is 30-60°. A wet... A temperature sensor is used; a concrete strain gauge is placed at the midpoint of each of the two long sides of the rectangle at an angle of 30-60° with the long side of the rectangle; a humidity sensor is placed in the area between the inclined concrete strain gauge and the wide side of the rectangle; the midpoint of the two long sides of the rectangle divides the rectangle into two equal areas, left and right, and a soil pressure gauge is placed at the center of each area; the horizontal distance between the rectangle and the edge of the driveway is 60cm, the length of the rectangle is 100cm, and the width of the rectangle is 60cm; in the hard shoulder area, a humidity sensor and a temperature sensor are placed sequentially from left to right, with a horizontal distance of 60cm between the humidity sensor and the temperature sensor, and a horizontal distance of 10cm between the temperature sensor and the rectangle.

[0017] A third monitoring unit is placed on the upper surface of the compacted subbase layer to test various road performance characteristics of the subbase layer. The horizontal distance between the third and second monitoring units is 10 cm. This unit includes fourteen concrete strain gauges, two earth pressure gauges, seven humidity sensors, and one temperature sensor. In the driveway area, the fourteen concrete strain gauges are arranged in a rectangle, with three strain gauges at each of the four vertices. Two strain gauges are arranged perpendicularly to each other on the horizontal plane, and one strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined strain gauge and the horizontal strain gauge is 60-70°. A wet... A temperature sensor is used; a concrete strain gauge is placed at the midpoint of each of the two long sides of the rectangle at an angle of 60-70° with the long side of the rectangle; a humidity sensor is placed in the area between the inclined concrete strain gauge and the wide side of the rectangle; the midpoint of the two long sides of the rectangle divides the rectangle into two equal areas, left and right, and a soil pressure gauge is placed at the center of each area; the horizontal distance between the rectangle and the edge of the driveway is 60cm, the length of the rectangle is 100cm, and the width of the rectangle is 60cm; in the hard shoulder area, a humidity sensor and a temperature sensor are placed sequentially from left to right, with a horizontal distance of 60cm between the humidity sensor and the temperature sensor, and a horizontal distance of 10cm between the temperature sensor and the rectangle.

[0018] In any of the above schemes, it is preferred that, in step four, a fourth monitoring unit is arranged on the upper surface of the compacted upper base layer to test various road performance characteristics of the underlying layers. The horizontal distance between the fourth monitoring unit and the third monitoring unit is 10cm. The fourth monitoring unit includes fourteen asphalt strain gauges, two earth pressure gauges, two vertical strain gauges, one humidity sensor, and one temperature sensor. In the driving lane area, the fourteen asphalt strain gauges are arranged in a rectangle, with three asphalt strain gauges arranged at each of the four vertices of the rectangle. Two asphalt strain gauges are arranged perpendicularly to each other on the horizontal plane, and one asphalt strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined asphalt strain gauge and the horizontal asphalt strain gauge is 40-60°. An asphalt strain gauge is placed at an angle of 40-60° between the midpoint of each of the two long sides of the rectangle. The midpoint of the two long sides divides the rectangle into two equal regions, left and right. An earth pressure gauge is placed at the center of each region. Two vertical strain gauges are placed 20cm to the left of the rectangle, perpendicular to the horizontal plane. The horizontal distance between the rectangle and the edge of the roadway is 60cm. The length of the rectangle is 100cm, and the width is 60cm. In the hard shoulder area, a humidity sensor and a temperature sensor are placed from left to right. The horizontal distance between the humidity sensor and the temperature sensor is 60cm, and the horizontal distance between the temperature sensor and the rectangle is 10cm.

[0019] A fifth monitoring unit is arranged on the upper surface of the compacted lower layer to test various road performance parameters of the middle layer. The horizontal distance between the fifth and fourth monitoring units is 10 cm. This unit includes fourteen asphalt strain gauges, two earth pressure gauges, two vertical strain gauges, one humidity sensor, and one temperature sensor. In the driving lane area, the fourteen asphalt strain gauges are arranged in a rectangle, with three strain gauges at each of the four vertices. Two strain gauges are arranged perpendicularly to each other on the horizontal plane, and one strain gauge is arranged at an angle of 60-80° between the inclined strain gauge and the horizontal strain gauge. The midpoints of the two long sides of the rectangle... An asphalt strain gauge is placed at an angle of 60-80° with the long side of the rectangle. The midpoints of the two long sides of the rectangle divide it into two equal regions, left and right. An earth pressure gauge is placed at the center of each region. Two vertical strain gauges are placed 20cm to the left of the rectangle, perpendicular to the horizontal plane. The horizontal distance between the rectangle and the edge of the roadway is 60cm. The length and width of the rectangle are 100cm. In the hard shoulder area, a humidity sensor and a temperature sensor are placed from left to right. The horizontal distance between the humidity sensor and the temperature sensor is 60cm, and the horizontal distance between the temperature sensor and the rectangle is 10cm.

[0020] In any of the above schemes, it is preferred that, in step five, the arrangement structure of the sub-base monitoring unit, the lower base monitoring unit, the upper base monitoring unit, the lower surface monitoring unit, and the middle surface monitoring unit is the same as the arrangement structure of the first monitoring unit, the second monitoring unit, the third monitoring unit, the fourth monitoring unit, and the fifth monitoring unit, respectively.

[0021] In any of the above schemes, it is preferred that, in step four, the compaction degree of each layer is not less than 94%; in step five, the compaction degree of each test piece is not less than 94%, and the wheel load pressure of the accelerated loading test is 0.7 MPa and the wheel load speed is 4800 times / hour.

[0022] In this invention, for poorly designed paving layers, the thickness is adjusted by increasing it by 1cm each time.

[0023] This invention relates to six monitoring devices, including asphalt strain gauges, concrete strain gauges, vertical strain gauges, earth pressure gauges, temperature sensors, and humidity sensors. The asphalt strain gauges are used to monitor the lateral and longitudinal strain of the asphalt surface layer caused by vehicle loads, helping to assess fatigue cracking of the asphalt surface layer and predict the fatigue life of the asphalt pavement. The concrete strain gauges are used to monitor the lateral and longitudinal strain of the road base layer under the combined effects of vehicle loads and environmental factors, helping to assess fatigue cracking of the base layer and predict the fatigue life of the road. The vertical strain gauges are used to monitor the vertical deformation of the asphalt surface layer, helping to assess structural damage caused by excessive deformation, such as rutting. The earth pressure gauges are used to monitor the vertical pressure at the bottom of each layer of the road under vehicle moving loads, helping to assess the load-bearing capacity and stability of the pavement structure. The temperature sensors are used to monitor temperature changes in each layer of the road, obtaining short-term, long-term, and daily temperature changes and spatial distribution of the pavement, helping to study pavement structural performance and seasonal temperature changes. The humidity sensors are used to monitor the humidity of each layer of the road, helping to assess the moisture content of each layer material and its impact on the pavement structure.

[0024] The road rollers, various monitoring devices, monitoring systems, and accelerated loading test equipment used in this invention are all existing technologies, and there are no special requirements for the equipment models and specific structures.

[0025] In this invention, both the road surface layer and base layer utilize recycled materials. The performance of the recycled asphalt mixture is similar to that of fresh asphalt mixture, although some specific properties may differ. Cement-stabilized and lime-fly ash-stabilized high-strength brick-concrete composite with recycled aggregate from construction waste exhibits good water stability and durability. However, under vehicle loads, the low initial strength of recycled materials may lead to significant deformation in the early stages of use, and prolonged vehicle loads may result in fatigue cracking. Therefore, oblique strain gauges are necessary in this pavement structure. Oblique placement allows for more comprehensive monitoring of stress distribution within the pavement structure, aiding in the analysis of interactions between different material layers. Simultaneously, obliquely placed strain gauges can more accurately monitor the deformation of each road layer under multi-axial loads, providing more comprehensive deformation data. Furthermore, the oblique placement of strain gauges can monitor the generation and propagation of fatigue cracks, contributing to the development of appropriate maintenance and reinforcement plans.

[0026] According to the integrated design method of recycled pavement structure and materials based on road performance balance of the present invention, it is possible to explore integrated design schemes of recycled pavement structure and materials suitable for different roads. The structure and materials of the main road pavement are as follows: the thickness of the top layer is 4cm, and the material is the recycled asphalt mixture designed in this invention; the thickness of the middle layer is 6cm, and the material is the recycled asphalt mixture designed in this invention; the thickness of the bottom layer is 6-8cm, and the material is the recycled asphalt mixture designed in this invention; the thickness of the upper base layer is 16-18cm, and the material is the recycled inorganic mixture designed in this invention; the thickness of the lower base layer is 16-18cm, and the material is the recycled inorganic mixture designed in this invention; the thickness of the subbase layer is 16-18cm, and the material is the recycled inorganic mixture designed in this invention; the thickness of the subgrade is not less than 40cm.

[0027] This invention, based on an integrated design method for recycled pavement structure and materials that balances road performance, has the following beneficial effects: (1) It can effectively integrate recycled materials such as construction waste and optimize the structural design of recycled pavement. Traditional pavement design usually uses new materials, while the recycling of construction waste can not only reduce the pollution of waste to the environment, but also reduce the cost of pavement construction. Through reasonable material ratio and structural design, construction waste can be used more widely and efficiently in recycled pavement, thereby reducing dependence on natural resources and realizing the sustainable use of resources.

[0028] (2) By balancing the design of road performance, the performance and durability of recycled pavement are improved. The performance of recycled pavement materials may vary depending on their source. Through an integrated design approach, the optimal match between pavement structure and materials can be achieved, ensuring that the pavement's comprehensive performance, such as strength, wear resistance, and crack resistance, reaches or even exceeds that of traditional pavement. This not only extends the service life of the pavement and reduces traffic disruption and additional costs caused by frequent maintenance, but also improves the overall safety and comfort of the pavement.

[0029] (3) Advanced sensor technology has been introduced to monitor and evaluate the performance of recycled pavement structures in real time. By integrating a sensor network inside the pavement, data such as pavement temperature, humidity, stress, and strain can be collected in real time, enabling timely detection and early warning of potential structural problems. This full-structure monitoring not only helps to make pavement maintenance decisions more scientific and precise, but also, through big data analysis, can further optimize the design and material selection of recycled pavement, and improve the design quality and construction level of subsequent projects.

[0030] (4) In practical applications, the efficient utilization of construction waste and optimized design of road performance can significantly reduce the environmental impact and economic cost of road engineering. Given the scarcity of resources and increasingly stringent environmental requirements, this method provides a green, economical, and efficient technical route for urban infrastructure construction. Compared with traditional methods, this patent not only achieves environmental benefits but also provides strong guarantees for the long-term effectiveness and durability of road engineering, possessing broad promotional value and application prospects.

[0031] (5) Through innovative design concepts and technical means, this invention has realized the resource utilization of construction waste and the comprehensive improvement of road surface performance. It not only improves the structural performance of recycled road surface, but also provides technical support for intelligent monitoring and maintenance, and makes an important contribution to the sustainable development of modern transportation infrastructure. Attached Figure Description

[0032] Figure 1 This is a diagram showing the overall layout of monitoring units at each layer when laying recycled pavement at a construction site, according to a preferred embodiment of the integrated design method for recycled pavement structure and materials based on road performance balance of the present invention. Figure 2 for Figure 1 The diagram shows the specific layout of the grassroots monitoring units (first monitoring unit, second monitoring unit, and third monitoring unit) in the illustrated embodiment; Figure 3 for Figure 1 The diagram shows the specific layout of the surface monitoring units (fourth monitoring unit and fifth monitoring unit) in the illustrated embodiment.

[0033] The diagram is labeled as follows: 1-subgrade, 2-subbase, 3-lower base course, 4-upper base course, 5-lower layer, 6-intermediate layer, 7-upper layer, 8-first monitoring unit, 9-second monitoring unit, 10-third monitoring unit, 11-fourth monitoring unit, 12-fifth monitoring unit, 13-asphalt strain gauge, 14-concrete strain gauge, 15-vertical strain gauge, 16-soil pressure gauge, 17-temperature sensor, 18-humidity sensor. Detailed Implementation

[0034] To further understand the invention, the following detailed description of the invention will be provided in conjunction with specific embodiments.

[0035] Example 1: like Figure 1-3 As shown, according to a preferred embodiment of the integrated design method for recycled pavement structure and materials based on road performance balance of the present invention, the design method includes the following steps in sequence: Step 1: Mill off the asphalt mixture from the actual road surface material and reprocess it to obtain recycled asphalt mixture. Use the obtained recycled asphalt mixture as the surface material of the recycled pavement. The surface layer of the recycled pavement includes a lower layer 5, a middle layer 6, and a top layer 7. Step 2: Prepare recycled inorganic mixture according to design requirements, and use the prepared recycled inorganic mixture as the base material of recycled pavement. The base of recycled pavement includes subbase 2, lower base 3 and upper base 4. Step 3: Prepare several monitoring devices and check them to ensure that each monitoring device can be used normally; Step 4: At the construction site, the recycled pavement is laid according to the design requirements. First, the subgrade 1 is leveled. Then, from bottom to top, the subbase 2, lower base 3, upper base 4, lower layer 5, intermediate layer 6, and upper layer 7 are laid on top of the subbase 1. During the paving process, each layer is compacted with a road roller. Simultaneously, during the paving process, the first monitoring unit 8, the second monitoring unit 9, the third monitoring unit 10, the fourth monitoring unit 11, and the fifth monitoring unit 12 are arranged on the upper surface of the subbase 1 and the upper surface of the compacted subbase 2, lower base 3, upper base 4, and lower layer 5, respectively. Finally, vehicles are allowed to travel on the overall recycled pavement, entering from one end and exiting from the other. During vehicle travel, the first monitoring unit 8, the second monitoring unit 9, the third monitoring unit 10, the fourth monitoring unit 11, and the fifth monitoring unit 12 monitor the various road performance characteristics of the subbase 2, lower base 3, upper base 4, lower layer 5, and intermediate layer 6, respectively, and the monitoring results are fed back to the monitoring system. Step 5: In the laboratory, lay the recycled pavement test specimens according to the design requirements. First, lay the subbase test specimen. On the test platform, lay the subgrade, subbase monitoring unit, and subbase layer sequentially from bottom to top, and compact it using static pressure. After compaction, conduct an accelerated loading test. During the accelerated loading test, the subbase monitoring unit monitors various pavement performance characteristics of the subbase layer. Next, lay the lower base test specimen. On the test platform, lay the subbase, lower base monitoring unit, and lower base layer sequentially from bottom to top, and compact it using static pressure. After compaction, conduct an accelerated loading test. During the accelerated loading test, the lower base monitoring unit monitors various pavement performance characteristics of the lower base layer. Finally, lay the upper base test specimen. On the test platform, lay the lower base layer, upper base monitoring unit, and lower base layer sequentially from bottom to top. The upper base course was compacted using static pressure, followed by an accelerated loading test. During the accelerated loading test, the upper base course monitoring unit monitored various road performance characteristics of the bottom layer of the upper base course. Next, the lower base course test specimen was laid. On the test platform, the upper base course, lower base course monitoring unit, and lower base course were laid sequentially from bottom to top, and compacted using static pressure. After compaction, an accelerated loading test was conducted, during which the lower base course monitoring unit monitored various road performance characteristics of the bottom layer of the lower base course. Finally, the middle layer test specimen was laid. On the test platform, the lower base course, middle layer monitoring unit, and middle layer were laid sequentially from bottom to top, and compacted using static pressure. After compaction, an accelerated loading test was conducted, during which the middle layer monitoring unit monitored various road performance characteristics of the bottom layer of the middle layer. Step Six: Compare the various road performance parameters of the subbase, lower base, upper base, lower layer, and intermediate layer bottom obtained from on-site monitoring with the various road performance parameters of the subbase, lower base, upper base, lower layer, and intermediate layer bottom obtained from laboratory monitoring. Verify the rationality of the integrated design of recycled pavement structure and materials based on road performance balance based on the comparison results. In step six, if the average deviation of each pavement performance item obtained from on-site monitoring is no greater than 3% of the average deviation of each pavement performance item obtained from laboratory monitoring, it indicates that the integrated design of recycled pavement structure and materials based on pavement performance balance is reasonable. If the average deviation of a certain pavement performance item obtained from on-site monitoring is greater than 3% of the corresponding average deviation of the pavement performance item obtained from laboratory monitoring, it indicates that the integrated design of recycled pavement structure and materials based on pavement performance balance is unreasonable. For paving layers with unreasonable designs, their thickness needs to be adjusted.

[0036] In step one, the method for preparing the recycled asphalt mixture is as follows: first, the asphalt mixture of the actual road surface material is milled and recycled; then, the recycled asphalt mixture is subjected to secondary crushing and secondary screening to obtain recycled aggregate; finally, the recycled aggregate, new aggregate, mineral powder and emulsified asphalt are put into a mixer and stirred to obtain the recycled asphalt mixture.

[0037] The mass percentages of each substance in the recycled asphalt mixture are as follows: recycled aggregate accounts for 55 wt%, new aggregate accounts for 25 wt%, mineral powder accounts for 10 wt%, and emulsified asphalt accounts for 10 wt%; the mixing temperature is 175℃ and the mixing time is 90 s.

[0038] In step two, the mass percentage of each substance in the recycled inorganic mixture is as follows: cement accounts for 6.5 wt%, recycled aggregate from high-strength brick-concrete construction waste accounts for 88 wt%, and water accounts for 5.5 wt%. The substances are placed in a mixer and stirred at room temperature, at a stirring speed of 48 r / min, and for 2 min.

[0039] The cement is PO 32.5 slag silicate cement; the high-quality brick-concrete construction waste recycled aggregate is construction waste generated from the demolition of brick-concrete buildings, with a brick-concrete content of 70wt%, wherein the aggregate with particle sizes of 20-31.5mm, 10-20mm, 5-10mm, and 0-5mm accounts for 10%, 25%, 30%, and 35% of the mass of the high-quality brick-concrete construction waste recycled aggregate, respectively.

[0040] In step three, the monitoring devices include asphalt strain gauge 13, concrete strain gauge 14, vertical strain gauge 15, earth pressure gauge 16, temperature sensor 17, and humidity sensor 18.

[0041] In step four, a first monitoring unit 8 is arranged on the upper surface of the subgrade 1 to test various road performance characteristics of the subbase 2. This unit includes fourteen concrete strain gauges 14, two earth pressure gauges 16, seven humidity sensors 18, and one temperature sensor 17. In the driveway area, the fourteen concrete strain gauges 14 are arranged in a rectangle, with three strain gauges 14 at each of the four vertices. Two strain gauges 14 are arranged perpendicularly to each other on the horizontal plane, and one strain gauge 14 is arranged at an angle on the horizontal plane. The angle between the inclined strain gauge 14 and the horizontal strain gauge 14 is 25°. A humidity sensor 18 is placed in the angled area between the inclined strain gauge 14 and the vertical strain gauge 14. A concrete strain gauge 14 is inclinedly arranged at the midpoint of each of the two long sides of the rectangle, with the angle between the inclined concrete strain gauge 14 and the long side of the rectangle being 25°. A humidity sensor 18 is arranged in the area between the inclined concrete strain gauge 14 and the wide side of the rectangle. The midpoint of the two long sides of the rectangle divides the rectangle into two equal regions, left and right. An earth pressure gauge 16 is arranged at the center of each of the left and right regions. The horizontal distance between the rectangle and the edge line of the driving lane is 60cm. The length of the rectangle is 100cm and the width of the rectangle is 60cm. In the hard shoulder area, a humidity sensor 18 and a temperature sensor 17 are arranged sequentially from left to right. The horizontal distance between the humidity sensor 18 and the temperature sensor 17 is 60cm, and the horizontal distance between the temperature sensor 17 and the rectangle is 10cm.

[0042] A second monitoring unit 9 is arranged on the upper surface of the compacted subbase 2 to test various road performance characteristics of the lower base layer 3. The horizontal distance between the second monitoring unit 9 and the first monitoring unit 8 is 10 cm. The second monitoring unit 9 includes fourteen concrete strain gauges 14, two earth pressure gauges 16, seven humidity sensors 18, and one temperature sensor 17. In the driveway area, the fourteen concrete strain gauges 14 are arranged in a rectangle, with three strain gauges 14 at each of the four vertices. Two strain gauges 14 are arranged perpendicularly to each other on the horizontal plane, and one strain gauge 14 is arranged at an angle on the horizontal plane. The angle between the inclined strain gauge 14 and the horizontal strain gauge 14 is 45°. The angle between the inclined strain gauge 14 and the vertical strain gauge 14 is distributed... A humidity sensor 18 is placed; a concrete strain gauge 14 is obliquely arranged at the midpoint of each of the two long sides of the rectangle, with the angle between the obliquely arranged concrete strain gauge 14 and the long side of the rectangle being 45°; a humidity sensor 18 is arranged in the area between the obliquely arranged concrete strain gauge 14 and the wide side of the rectangle; the midpoint of the two long sides of the rectangle divides the rectangle into two equal areas, left and right, and an earth pressure gauge 16 is arranged at the center of each of the two areas; the horizontal distance between the rectangle and the edge line of the driving lane is 60cm, the length of the rectangle is 100cm, and the width of the rectangle is 60cm; in the hard shoulder area, a humidity sensor 18 and a temperature sensor 17 are arranged sequentially from left to right, with the horizontal distance between the humidity sensor 18 and the temperature sensor 17 being 60cm, and the horizontal distance between the temperature sensor 17 and the rectangle being 10cm.

[0043] A third monitoring unit 10 is arranged on the upper surface of the compacted subbase 3 to test various road performance characteristics of the subbase 4. The horizontal distance between the third monitoring unit 10 and the second monitoring unit 9 is 10 cm. The unit includes fourteen concrete strain gauges 14, two earth pressure gauges 16, seven humidity sensors 18, and one temperature sensor 17. In the driveway area, the fourteen concrete strain gauges 14 are arranged in a rectangle, with three strain gauges 14 at each of the four apex corners. Two strain gauges 14 are arranged perpendicularly to each other on the horizontal plane, and one strain gauge 14 is arranged at an angle on the horizontal plane. The angle between the inclined strain gauge 14 and the horizontal strain gauge 14 is 65°. The angle between the inclined strain gauge 14 and the vertical strain gauge 14 is [not specified in the original text]. A humidity sensor 18 is installed; a concrete strain gauge 14 is installed at the midpoint of each of the two long sides of the rectangle at an angle of 65° between the inclined concrete strain gauge 14 and the long side of the rectangle, and a humidity sensor 18 is installed in the area between the inclined concrete strain gauge 14 and the wide side of the rectangle; the midpoint of the two long sides of the rectangle divides the rectangle into two equal areas, left and right, and an earth pressure gauge 16 is installed at the center of each of the two areas; the horizontal distance between the rectangle and the edge line of the driving lane is 60cm, the length of the rectangle is 100cm, and the width of the rectangle is 60cm; in the hard shoulder area, a humidity sensor 18 and a temperature sensor 17 are installed from left to right, the horizontal distance between the humidity sensor 18 and the temperature sensor 17 is 60cm, and the horizontal distance between the temperature sensor 17 and the rectangle is 10cm.

[0044] A fourth monitoring unit 11 is arranged on the upper surface of the compacted upper base layer 4 to test various road performance characteristics of the lower base layer 5. The horizontal distance between the fourth monitoring unit 11 and the third monitoring unit 10 is 10 cm. It includes fourteen asphalt strain gauges 13, two earth pressure gauges 16, two vertical strain gauges 15, one humidity sensor 18, and one temperature sensor 17. In the driving lane area, the fourteen asphalt strain gauges 13 are arranged in a rectangle, with three asphalt strain gauges 13 at each of the four vertices. Two asphalt strain gauges 13 are arranged perpendicularly to each other on the horizontal plane, and one asphalt strain gauge 13 is arranged at an angle of 50° between the inclined asphalt strain gauge 13 and the horizontally arranged asphalt strain gauge 13. An asphalt strain gauge 13 is inclinedly arranged at the midpoint of each of the two long sides, with the angle between the inclined asphalt strain gauge 13 and the long side of the rectangle being 50°. The midpoint of the two long sides of the rectangle divides the rectangle into two equal regions, left and right. An earth pressure gauge 16 is arranged at the center of each of the left and right regions. Two vertical strain gauges 15 are arranged vertically on the horizontal plane 20cm to the left of the rectangle. The horizontal distance between the rectangle and the edge line of the driving lane is 60cm. The length of the rectangle is 100cm and the width of the rectangle is 60cm. In the hard shoulder area, a humidity sensor 18 and a temperature sensor 17 are arranged sequentially from left to right. The horizontal distance between the humidity sensor 18 and the temperature sensor 17 is 60cm, and the horizontal distance between the temperature sensor 17 and the rectangle is 10cm.

[0045] A fifth monitoring unit 12 is arranged on the upper surface of the compacted lower layer 5 to test various road performance characteristics of the bottom layer 6. The horizontal distance between the fifth monitoring unit 12 and the fourth monitoring unit 11 is 10 cm. It includes fourteen asphalt strain gauges 13, two earth pressure gauges 16, two vertical strain gauges 15, one humidity sensor 18, and one temperature sensor 17. In the driving lane area, the fourteen asphalt strain gauges 13 are arranged in a rectangle, with three asphalt strain gauges 13 at each of the four vertices. Two asphalt strain gauges 13 are arranged perpendicularly to each other on the horizontal plane, and one asphalt strain gauge 13 is arranged at an angle of 70° between the inclined asphalt strain gauge 13 and the horizontally arranged asphalt strain gauge 13. An asphalt strain gauge 13 is inclinedly arranged at the midpoint of each of the two long sides of the rectangle, with the angle between the inclined asphalt strain gauge 13 and the long side of the rectangle being 70°. The midpoint of the two long sides of the rectangle divides the rectangle into two equal regions, left and right. An earth pressure gauge 16 is arranged at the center of each of the left and right regions. Two vertical strain gauges 15 are arranged vertically on the horizontal plane 20cm to the left of the rectangle. The horizontal distance between the rectangle and the edge line of the driving lane is 60cm. The length of the rectangle is 100cm and the width of the rectangle is 60cm. In the hard shoulder area, a humidity sensor 18 and a temperature sensor 17 are arranged sequentially from left to right. The horizontal distance between the humidity sensor 18 and the temperature sensor 17 is 60cm, and the horizontal distance between the temperature sensor 17 and the rectangle is 10cm.

[0046] In step five, the arrangement of the subbase monitoring unit, lower base monitoring unit, upper base monitoring unit, lower surface monitoring unit, and intermediate surface monitoring unit is the same as that of the first, second, third, fourth, and fifth monitoring units, respectively. In step four, the compaction degree of each layer is not less than 94%; in step five, the compaction degree of each test specimen is not less than 94%, and the wheel load pressure of the accelerated loading test is 0.7 MPa and the wheel load speed is 4800 times / hour.

[0047] In this embodiment, for poorly designed paving layers, the thickness is adjusted by increasing the thickness by 1cm each time.

[0048] This embodiment involves six monitoring devices, including asphalt strain gauges, concrete strain gauges, vertical strain gauges, earth pressure gauges, temperature sensors, and humidity sensors. The asphalt strain gauges monitor the lateral and longitudinal strain of the asphalt surface layer caused by vehicle loads, helping to assess fatigue cracking and predict the fatigue life of the asphalt pavement. The concrete strain gauges monitor the lateral and longitudinal strain of the road base layer under the combined effects of vehicle loads and environmental factors, helping to assess fatigue cracking and predict the fatigue life of the road. The vertical strain gauges monitor the vertical deformation of the asphalt surface layer, helping to assess structural damage caused by excessive deformation, such as rutting. The earth pressure gauges monitor the vertical pressure at the bottom of each road layer under vehicle moving loads, helping to assess the bearing capacity and stability of the pavement structure. The temperature sensors monitor temperature changes in each road layer, obtaining short-term, long-term, and daily temperature variations and spatial distribution, helping to study pavement structural performance and seasonal temperature changes. The humidity sensors monitor the humidity of each road layer, helping to assess the moisture content of each layer's materials and its impact on the pavement structure.

[0049] The road roller, various monitoring devices, monitoring systems, and accelerated loading test equipment used in this embodiment are all existing technologies, and there are no special requirements for the equipment model and specific structure.

[0050] According to the integrated design method of recycled pavement structure-materials based on road performance balance in this embodiment, it is possible to explore integrated design schemes of recycled pavement structure-materials suitable for different roads. The structure and materials of the main road pavement are as follows: the thickness of the top layer is 4cm, and the material is the recycled asphalt mixture designed in this embodiment; the thickness of the middle layer is 6cm, and the material is the recycled asphalt mixture designed in this embodiment; the thickness of the bottom layer is 8cm, and the material is the recycled asphalt mixture designed in this embodiment; the thickness of the upper base layer is 18cm, and the material is the recycled inorganic mixture designed in this embodiment; the thickness of the lower base layer is 18cm, and the material is the recycled inorganic mixture designed in this embodiment; the thickness of the subbase layer is 18cm, and the material is the recycled inorganic mixture designed in this embodiment; the thickness of the subgrade is 40cm.

[0051] This embodiment is based on the integrated design method of recycled pavement structure and materials for road performance balance, which has the following beneficial effects: (1) It can effectively integrate recycled materials such as construction waste, optimize the design of recycled pavement structure, and through reasonable material ratio and structural design, construction waste can be more widely and efficiently applied in recycled pavement. (2) Through integrated design, the best match can be achieved between pavement structure and materials, ensuring that the comprehensive performance of pavement strength, wear resistance and crack resistance reaches or even exceeds that of traditional pavement. (3) By integrating a monitoring device network inside the pavement, data such as temperature, humidity, stress and strain of the pavement can be collected in real time, and potential structural problems can be detected and warned in a timely manner. (4) In practical applications, through the efficient utilization of construction waste and the optimized design of road performance, the environmental impact and economic cost of pavement engineering can be significantly reduced. (5) Through innovative design concepts and technical means, the resource utilization of construction waste and the comprehensive improvement of pavement performance have been realized, which not only improves the structural performance of recycled pavement, but also provides technical support for intelligent monitoring and maintenance.

[0052] Example 2: According to another preferred embodiment of the integrated design method for recycled pavement structure and materials based on road performance balance of the present invention, its design steps, paving structure, monitoring devices and equipment used, technical principles and beneficial effects are basically the same as those of embodiment one, except that: In step one, the mass percentage of each substance in the recycled asphalt mixture is as follows: recycled aggregate accounts for 50 wt%, new aggregate accounts for 20 wt%, mineral powder accounts for 15 wt%, and emulsified asphalt accounts for 15 wt%; the mixing temperature is 175℃ and the mixing time is 90 s.

[0053] In step two, the mass percentages of each substance in the recycled inorganic mixture are as follows: cement 6 wt%, recycled aggregate from high-strength brick-concrete construction waste 89 wt%, and water 5 wt%. All substances are placed in a mixer and stirred at room temperature, at a stirring speed of 45 r / min, for 3 min. The cement is PO 32.5 slag silicate cement. The recycled aggregate from high-strength brick-concrete construction waste is construction waste generated from the demolition of brick-concrete buildings, with a brick-concrete content of 80 wt%. The aggregate with particle sizes of 20-31.5 mm, 10-20 mm, 5-10 mm, and 0-5 mm accounts for 15%, 20%, 30%, and 35% of the total mass of the recycled aggregate, respectively.

[0054] In step four, in the first monitoring unit, three concrete strain gauges are arranged at the four vertices of the rectangle, two of which are arranged perpendicularly to each other on the horizontal plane and one is arranged at an angle on the horizontal plane, with the angle between the inclined concrete strain gauge and the horizontal concrete strain gauge being 30°; a concrete strain gauge is arranged at an angle at the midpoint of each of the two long sides of the rectangle, with the angle between the inclined concrete strain gauge and the long side of the rectangle being 30°.

[0055] In the second monitoring unit, three concrete strain gauges are arranged at the four vertices of the rectangle. Two of the concrete strain gauges are arranged perpendicularly to each other on the horizontal plane, and one concrete strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined concrete strain gauge and the horizontal concrete strain gauge is 60°. A concrete strain gauge is arranged at an angle at the midpoint of each of the two long sides of the rectangle. The angle between the inclined concrete strain gauge and the long side of the rectangle is 60°.

[0056] In the third monitoring unit, three concrete strain gauges are arranged at the four vertices of the rectangle. Two of the concrete strain gauges are arranged perpendicularly to each other on the horizontal plane, and one concrete strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined concrete strain gauge and the horizontal concrete strain gauge is 70°. A concrete strain gauge is arranged at an angle at the midpoint of each of the two long sides of the rectangle. The angle between the inclined concrete strain gauge and the long side of the rectangle is 70°.

[0057] In the fourth monitoring unit, three asphalt strain gauges are arranged at the four vertices of the rectangle. Two asphalt strain gauges are arranged perpendicularly to each other on the horizontal plane, and one asphalt strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined asphalt strain gauge and the horizontal asphalt strain gauge is 60°. An asphalt strain gauge is arranged at an angle at the midpoint of each of the two long sides of the rectangle. The angle between the inclined asphalt strain gauge and the long side of the rectangle is 60°.

[0058] In the fifth monitoring unit, three asphalt strain gauges are arranged at the four vertices of the rectangle. Two asphalt strain gauges are arranged perpendicularly to each other on the horizontal plane, and one asphalt strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined asphalt strain gauge and the horizontal asphalt strain gauge is 80°. An asphalt strain gauge is arranged at an angle at the midpoint of each of the two long sides of the rectangle. The angle between the inclined asphalt strain gauge and the long side of the rectangle is 80°.

[0059] Example 3: According to another preferred embodiment of the integrated design method for recycled pavement structure and materials based on road performance balance of the present invention, its design steps, paving structure, monitoring devices and equipment used, technical principles and beneficial effects are basically the same as those of embodiment one, except that: In step one, the mass percentage of each substance in the recycled asphalt mixture is as follows: recycled aggregate accounts for 60 wt%, new aggregate accounts for 20 wt%, mineral powder accounts for 8 wt%, and emulsified asphalt accounts for 12 wt%; the mixing temperature is 175℃ and the mixing time is 90 s.

[0060] In step two, the mass percentages of each substance in the recycled inorganic mixture are as follows: cement 7 wt%, recycled aggregate from high-strength brick-concrete construction waste 87 wt%, and water 6 wt%. The substances are placed in a mixer and stirred at room temperature for 1 minute at a speed of 50 rpm. The cement is PO 32.5 slag silicate cement. The recycled aggregate from high-strength brick-concrete construction waste is construction waste generated from the demolition of brick-concrete buildings, with a brick-concrete content of 80 wt%. The aggregate with particle sizes of 20-31.5 mm, 10-20 mm, 5-10 mm, and 0-5 mm accounts for 15%, 25%, 25%, and 35% of the total mass of the recycled aggregate, respectively.

[0061] In step four, in the first monitoring unit, three concrete strain gauges are arranged at the four vertices of the rectangle, two of which are arranged perpendicularly to each other on the horizontal plane, and one is arranged at an angle on the horizontal plane. The angle between the inclined concrete strain gauge and the horizontal concrete strain gauge is 20°. A concrete strain gauge is arranged at an angle at the midpoint of each of the two long sides of the rectangle. The angle between the inclined concrete strain gauge and the long side of the rectangle is 20°.

[0062] In the second monitoring unit, three concrete strain gauges are arranged at the four vertices of the rectangle. Two of the concrete strain gauges are arranged perpendicularly to each other on the horizontal plane, and one concrete strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined concrete strain gauge and the horizontal concrete strain gauge is 30°. A concrete strain gauge is arranged at an angle at the midpoint of each of the two long sides of the rectangle. The angle between the inclined concrete strain gauge and the long side of the rectangle is 30°.

[0063] In the third monitoring unit, three concrete strain gauges are arranged at the four vertices of the rectangle. Two of the concrete strain gauges are arranged perpendicularly to each other on the horizontal plane, and one concrete strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined concrete strain gauge and the horizontal concrete strain gauge is 60°. A concrete strain gauge is arranged at an angle at the midpoint of each of the two long sides of the rectangle. The angle between the inclined concrete strain gauge and the long side of the rectangle is 60°.

[0064] In the fourth monitoring unit, three asphalt strain gauges are arranged at the four vertices of the rectangle. Two asphalt strain gauges are arranged perpendicularly to each other on the horizontal plane, and one asphalt strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined asphalt strain gauge and the horizontal asphalt strain gauge is 40°. An asphalt strain gauge is arranged at an angle at the midpoint of each of the two long sides of the rectangle. The angle between the inclined asphalt strain gauge and the long side of the rectangle is 40°.

[0065] In the fifth monitoring unit, three asphalt strain gauges are arranged at each of the four vertices of the rectangle. Two of the asphalt strain gauges are arranged perpendicularly to each other on the horizontal plane, and one asphalt strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined asphalt strain gauge and the horizontal asphalt strain gauge is 60°. An asphalt strain gauge is arranged at an angle at the midpoint of each of the two long sides of the rectangle. The angle between the inclined asphalt strain gauge and the long side of the rectangle is 60°.

[0066] Example 4: According to another preferred embodiment of the integrated design method for recycled pavement structure and materials based on road performance balance of the present invention, its design steps, paving structure, monitoring devices and equipment used, technical principles and beneficial effects are basically the same as those of embodiments one to three, except that: In step two, the mass percentages of each substance in the recycled inorganic mixture are as follows: lime 4 wt%, fly ash 10 wt%, recycled aggregate from high-strength brick-concrete construction waste 81 wt%, and water 5 wt%. All substances are placed in a mixer and stirred at room temperature, at a stirring speed of 42 r / min, for 2 min. The lime is magnesian quicklime, containing 65% effective CaO, 5% effective MgO, and the remainder being impurities. The fly ash contains 35% Al₂O₃, 4% Fe₂O₃, and 55% SiO₂, with the remainder being impurities. The fly ash has a loss on ignition of 7% and a specific surface area of ​​480 m². 2 / kg.

[0067] Example 5: According to another preferred embodiment of the integrated design method for recycled pavement structure and materials based on road performance balance of the present invention, its design steps, paving structure, monitoring devices and equipment used, technical principles and beneficial effects are basically the same as those of embodiments one to three, except that: In step two, the mass percentages of each substance in the recycled inorganic mixture are as follows: lime 5 wt%, fly ash 9 wt%, recycled aggregate from high-strength brick-concrete construction waste 81 wt%, and water 5 wt%. All substances are placed in a mixer and stirred at room temperature, at a stirring speed of 45 r / min, for 3 min. The lime is magnesian quicklime, containing 60% effective CaO, 6% effective MgO, and the remainder being impurities. The fly ash contains 30% Al2O3, 5% Fe2O3, and 60% SiO2, with the remainder being impurities. The fly ash has a loss on ignition of 8% and a specific surface area of ​​450 m². 2 / kg.

[0068] Example 6: According to another preferred embodiment of the integrated design method for recycled pavement structure and materials based on road performance balance of the present invention, its design steps, paving structure, monitoring devices and equipment used, technical principles and beneficial effects are basically the same as those of embodiments one to three, except that: In step two, the mass percentages of each substance in the recycled inorganic mixture are as follows: lime 4 wt%, fly ash 9 wt%, recycled aggregate from high-strength brick-concrete construction waste 82 wt%, and water 5 wt%. All substances are placed in a mixer and stirred at room temperature, at a stirring speed of 50 r / min, for 1 min. The lime is magnesian quicklime, containing 70% effective CaO, 6% effective MgO, and the remainder being impurities. The fly ash contains 40% Al2O3, 5% Fe2O3, and 50% SiO2, with the remainder being impurities. The fly ash has a loss on ignition of 8% and a specific surface area of ​​500 m². 2 / kg.

[0069] Special Note: The technical solution of this invention involves numerous parameters, and the synergistic effects between these parameters must be comprehensively considered to achieve the beneficial effects and significant progress of this invention. Furthermore, the value ranges of each parameter in the technical solution were obtained through extensive experimentation. For each parameter and the combinations thereof, the inventors have recorded a large amount of experimental data; however, due to space limitations, the specific experimental data is not disclosed here.

[0070] Those skilled in the art will readily understand that the integrated design method of recycled pavement structure and materials based on road performance balance of the present invention includes any combination of the inventive content and specific embodiments described in the above specification and the various parts shown in the accompanying drawings. Due to space limitations and for the sake of brevity, not all of these combined solutions have been described. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for integrated design of recycled pavement structure and materials based on road performance balance, characterized in that: The design method includes the following steps in sequence. Step 1: Mill off the asphalt mixture from the actual road surface material and reprocess it to obtain recycled asphalt mixture. Use the obtained recycled asphalt mixture as the surface material of the recycled pavement. The surface layer of the recycled pavement includes a bottom layer, a middle layer, and a top layer. Step 2: Prepare recycled inorganic mixture according to design requirements, and use the prepared recycled inorganic mixture as the base material of recycled pavement. The base of recycled pavement includes subbase, lower base and upper base. Step 3: Prepare several monitoring devices and check them to ensure that each monitoring device can be used normally; Step 4: At the construction site, the recycled pavement is laid according to the design requirements. First, the subgrade is leveled. Then, from bottom to top, the subbase, lower base course, upper base course, lower layer, intermediate layer, and upper layer are laid on top of the subbase. During the paving process, each layer is compacted using a road roller. Simultaneously, during the paving process, the first, second, third, fourth, and fifth monitoring units are placed on the upper surface of the subbase and the upper surfaces of the compacted subbase, lower base course, upper base course, and lower layer, respectively. Finally, vehicles are allowed to travel on the overall recycled pavement, entering from one end and exiting from the other. During vehicle travel, the first, second, third, fourth, and fifth monitoring units monitor various road performance characteristics of the subbase, lower base course, upper base course, lower layer, and intermediate layer, respectively, and feed the monitoring results back to the monitoring system. Step 5: In the laboratory, lay the recycled pavement test specimens according to the design requirements. First, lay the subbase test specimen. On the test platform, lay the subgrade, subbase monitoring unit, and subbase layer sequentially from bottom to top, and compact it using static pressure. After compaction, conduct an accelerated loading test. During the accelerated loading test, the subbase monitoring unit monitors various pavement performance characteristics of the subbase layer. Next, lay the lower base test specimen. On the test platform, lay the subbase, lower base monitoring unit, and lower base layer sequentially from bottom to top, and compact it using static pressure. After compaction, conduct an accelerated loading test. During the accelerated loading test, the lower base monitoring unit monitors various pavement performance characteristics of the lower base layer. Finally, lay the upper base test specimen. On the test platform, lay the lower base layer, upper base monitoring unit, and lower base layer sequentially from bottom to top. The upper base course was compacted using static pressure, followed by an accelerated loading test. During the accelerated loading test, the upper base course monitoring unit monitored various road performance characteristics of the bottom layer of the upper base course. Next, the lower base course test specimen was laid. On the test platform, the upper base course, lower base course monitoring unit, and lower base course were laid sequentially from bottom to top, and compacted using static pressure. After compaction, an accelerated loading test was conducted, during which the lower base course monitoring unit monitored various road performance characteristics of the bottom layer of the lower base course. Finally, the middle layer test specimen was laid. On the test platform, the lower base course, middle layer monitoring unit, and middle layer were laid sequentially from bottom to top, and compacted using static pressure. After compaction, an accelerated loading test was conducted, during which the middle layer monitoring unit monitored various road performance characteristics of the bottom layer of the middle layer. Step Six: Compare the various road performance parameters of the subbase, lower base, upper base, lower layer, and intermediate layer bottom obtained from on-site monitoring with the various road performance parameters of the subbase, lower base, upper base, lower layer, and intermediate layer bottom obtained from laboratory monitoring. Verify the rationality of the integrated design of recycled pavement structure and materials based on road performance balance based on the comparison results. In step six, if the average deviation of each pavement performance item obtained from on-site monitoring is no greater than 3% of the average deviation of each pavement performance item obtained from laboratory monitoring, it indicates that the integrated design of recycled pavement structure and materials based on pavement performance balance is reasonable. If the average deviation of a certain pavement performance item obtained from on-site monitoring is greater than 3% of the corresponding average deviation of the pavement performance item obtained from laboratory monitoring, it indicates that the integrated design of recycled pavement structure and materials based on pavement performance balance is unreasonable. For paving layers with unreasonable designs, their thickness needs to be adjusted.

2. The integrated design method for recycled pavement structure and materials based on road performance balance according to claim 1, characterized in that: In step one, the method for preparing the recycled asphalt mixture is as follows: first, the asphalt mixture of the actual road surface material is milled and recycled; then, the recycled asphalt mixture is subjected to secondary crushing and secondary screening to obtain recycled aggregate; finally, the recycled aggregate, new aggregate, mineral powder and emulsified asphalt are put into a mixer and stirred to obtain the recycled asphalt mixture. The mass percentages of each substance in the recycled asphalt mixture are as follows: recycled aggregate accounts for 50-60 wt%, new aggregate accounts for 20-30 wt%, mineral powder accounts for 8-15 wt%, and emulsified asphalt accounts for 10-15 wt%; the mixing temperature is 175℃ and the mixing time is 90 s.

3. The integrated design method for recycled pavement structure and materials based on road performance balance according to claim 2, characterized in that: In step two, the mass percentage of each substance in the recycled inorganic mixture is as follows: cement accounts for 6-7 wt%, recycled aggregate from high-strength brick-concrete construction waste accounts for 87-89 wt%, and water accounts for 5-6 wt%. The substances are placed in a mixer and stirred at room temperature, at a stirring speed of 45-50 r / min, and for 1-3 min. The cement is PO 32.5 slag silicate cement; the high-quality brick-concrete construction waste recycled aggregate is construction waste generated from the demolition of brick-concrete buildings, with a brick-concrete content of 60-80 wt%, wherein the aggregate with particle sizes of 20-31.5 mm, 10-20 mm, 5-10 mm, and 0-5 mm accounts for 10-15%, 20-25%, 25-30%, and 30-35% of the mass of the high-quality brick-concrete construction waste recycled aggregate, respectively.

4. The integrated design method for recycled pavement structure and materials based on road performance balance according to claim 2, characterized in that: In step two, the mass percentage of each substance in the recycled inorganic mixture is as follows: lime accounts for 4-5 wt%, fly ash accounts for 9-10 wt%, recycled aggregate from high-strength brick-concrete construction waste accounts for 81-82 wt%, and water accounts for 5-6 wt%. The substances are placed in a mixer and stirred at room temperature, at a stirring speed of 45-50 r / min, and for 1-3 min. The lime is magnesian quicklime, containing 60-70% effective CaO, 5-6% effective MgO, and the remainder being impurities; the fly ash contains 30-40% Al2O3, 4-5% Fe2O3, and 50-60% SiO2, with the remainder being impurities; the fly ash has a loss on ignition of 7-8% and a specific surface area of ​​450-500 m². 2 / kg; The recycled aggregate of high-quality brick-concrete construction waste is construction waste generated from the demolition of brick-concrete buildings, with a brick-concrete content of 60-80wt%, wherein the aggregate with particle sizes of 20-31.5mm, 10-20mm, 5-10mm, and 0-5mm accounts for 10-15%, 20-25%, 25-30%, and 30-35% of the mass of the recycled aggregate of high-quality brick-concrete construction waste, respectively.

5. The integrated design method for recycled pavement structure and materials based on road performance balance according to claim 3 or 4, characterized in that: In step three, the monitoring devices include asphalt strain gauges, concrete strain gauges, vertical strain gauges, earth pressure gauges, temperature sensors, and humidity sensors.

6. The integrated design method for recycled pavement structure and materials based on road performance balance according to claim 5, characterized in that: In step four, a first monitoring unit is deployed on the upper surface of the subgrade to test various road performance parameters of the subbase layer. This unit includes fourteen concrete strain gauges, two earth pressure gauges, seven humidity sensors, and one temperature sensor. In the driveway area, the fourteen concrete strain gauges are arranged in a rectangle, with three strain gauges at each of the four vertices. Two strain gauges are arranged perpendicularly to each other on the horizontal plane, and one strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined strain gauge and the horizontal strain gauge is 20-30°. A humidity sensor is placed in the angled area between the inclined and vertical strain gauges. The two longer sides of the rectangle... A concrete strain gauge is placed at an angle of 20-30° between the inclined concrete strain gauge and the long side of the rectangle. A humidity sensor is placed in the area between the inclined concrete strain gauge and the wide side of the rectangle. The midpoints of the two long sides of the rectangle divide it into two equal regions, left and right. An earth pressure gauge is placed at the center of each region. The horizontal distance between the rectangle and the edge of the roadway is 60cm. The length of the rectangle is 100cm and the width is 60cm. In the hard shoulder area, a humidity sensor and a temperature sensor are placed from left to right. The horizontal distance between the humidity sensor and the temperature sensor is 60cm, and the horizontal distance between the temperature sensor and the rectangle is 10cm. A second monitoring unit is arranged on the upper surface of the compacted subbase layer to test various road performance characteristics of the subbase layer. The horizontal distance between the second and first monitoring units is 10 cm. This unit includes fourteen concrete strain gauges, two earth pressure gauges, seven humidity sensors, and one temperature sensor. In the driveway area, the fourteen concrete strain gauges are arranged in a rectangle, with three strain gauges at each of the four vertices. Two strain gauges are arranged perpendicularly to each other on the horizontal plane, and one strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined strain gauge and the horizontal strain gauge is 30-60°. A wet... A temperature sensor is used; a concrete strain gauge is placed at the midpoint of each of the two long sides of the rectangle at an angle of 30-60° with the long side of the rectangle; a humidity sensor is placed in the area between the inclined concrete strain gauge and the wide side of the rectangle; the midpoint of the two long sides of the rectangle divides the rectangle into two equal areas, left and right, and a soil pressure gauge is placed at the center of each area; the horizontal distance between the rectangle and the edge of the driveway is 60cm, the length of the rectangle is 100cm, and the width of the rectangle is 60cm; in the hard shoulder area, a humidity sensor and a temperature sensor are placed sequentially from left to right, with a horizontal distance of 60cm between the humidity sensor and the temperature sensor, and a horizontal distance of 10cm between the temperature sensor and the rectangle; A third monitoring unit is placed on the upper surface of the compacted subbase layer to test various road performance characteristics of the subbase layer. The horizontal distance between the third and second monitoring units is 10 cm. This unit includes fourteen concrete strain gauges, two earth pressure gauges, seven humidity sensors, and one temperature sensor. In the driveway area, the fourteen concrete strain gauges are arranged in a rectangle, with three strain gauges at each of the four vertices. Two strain gauges are arranged perpendicularly to each other on the horizontal plane, and one strain gauge is arranged at an angle on the horizontal plane. The angle between the inclined strain gauge and the horizontal strain gauge is 60-70°. A wet... A temperature sensor is used; a concrete strain gauge is placed at the midpoint of each of the two long sides of the rectangle at an angle of 60-70° with the long side of the rectangle; a humidity sensor is placed in the area between the inclined concrete strain gauge and the wide side of the rectangle; the midpoint of the two long sides of the rectangle divides the rectangle into two equal areas, left and right, and a soil pressure gauge is placed at the center of each area; the horizontal distance between the rectangle and the edge of the driveway is 60cm, the length of the rectangle is 100cm, and the width of the rectangle is 60cm; in the hard shoulder area, a humidity sensor and a temperature sensor are placed sequentially from left to right, with a horizontal distance of 60cm between the humidity sensor and the temperature sensor, and a horizontal distance of 10cm between the temperature sensor and the rectangle.

7. The integrated design method for recycled pavement structure and materials based on road performance balance according to claim 6, characterized in that: In step four, a fourth monitoring unit is placed on the upper surface of the compacted upper base layer to test various road performance characteristics of the underlying layers. The horizontal distance between the fourth and third monitoring units is 10 cm. This fourth monitoring unit includes fourteen asphalt strain gauges, two earth pressure gauges, two vertical strain gauges, one humidity sensor, and one temperature sensor. In the driving lane area, the fourteen asphalt strain gauges are arranged in a rectangle, with three strain gauges at each of the four vertices. Two strain gauges are arranged perpendicularly to each other on the horizontal plane, and one strain gauge is arranged at an angle of 40-60° between the inclined strain gauge and the horizontal strain gauge. The two long sides of the rectangle... An asphalt strain gauge is placed at an angle of 40-60° with each of the two midpoints of the rectangle. The rectangle is divided into two equal regions by the midpoints of its two long sides, and an earth pressure gauge is placed at the center of each region. Two vertical strain gauges are placed vertically on the horizontal plane 20cm to the left of the rectangle. The horizontal distance between the rectangle and the edge of the roadway is 60cm, the length of the rectangle is 100cm, and the width of the rectangle is 60cm. In the hard shoulder area, a humidity sensor and a temperature sensor are placed sequentially from left to right. The horizontal distance between the humidity sensor and the temperature sensor is 60cm, and the horizontal distance between the temperature sensor and the rectangle is 10cm. A fifth monitoring unit is arranged on the upper surface of the compacted lower layer to test various road performance parameters of the middle layer. The horizontal distance between the fifth and fourth monitoring units is 10 cm. This unit includes fourteen asphalt strain gauges, two earth pressure gauges, two vertical strain gauges, one humidity sensor, and one temperature sensor. In the driving lane area, the fourteen asphalt strain gauges are arranged in a rectangle, with three strain gauges at each of the four vertices. Two strain gauges are arranged perpendicularly to each other on the horizontal plane, and one strain gauge is arranged at an angle of 60-80° between the inclined strain gauge and the horizontal strain gauge. The midpoints of the two long sides of the rectangle... An asphalt strain gauge is placed at an angle of 60-80° with the long side of the rectangle. The midpoints of the two long sides of the rectangle divide it into two equal regions, left and right. An earth pressure gauge is placed at the center of each region. Two vertical strain gauges are placed 20cm to the left of the rectangle, perpendicular to the horizontal plane. The horizontal distance between the rectangle and the edge of the roadway is 60cm. The length and width of the rectangle are 100cm. In the hard shoulder area, a humidity sensor and a temperature sensor are placed from left to right. The horizontal distance between the humidity sensor and the temperature sensor is 60cm, and the horizontal distance between the temperature sensor and the rectangle is 10cm.

8. The integrated design method for recycled pavement structure and materials based on road performance balance according to claim 7, characterized in that: In step five, the arrangement structure of the sub-base monitoring unit, lower base monitoring unit, upper base monitoring unit, lower surface monitoring unit, and middle surface monitoring unit is the same as that of the first monitoring unit, second monitoring unit, third monitoring unit, fourth monitoring unit, and fifth monitoring unit, respectively.

9. The integrated design method for recycled pavement structure and materials based on road performance balance according to claim 8, characterized in that: In step four, the compaction degree of each layer is not less than 94%; in step five, the compaction degree of each test piece is not less than 94%, and the wheel load pressure of the accelerated loading test is 0.7MPa and the wheel load speed is 4800 times / hour.

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