Dynamic testing method for bearing capacity of asphalt concrete pavement

Abstract

The invention relates to an asphalt concrete pavement bearing capacity dynamic test method, which comprises the following steps: S1, deploying a test vehicle, obtaining vehicle source data, and constructing a dynamic test vehicle model; s2, acquiring bituminous concrete pavement source data, and constructing a vehicle-road dynamic response model in combination with the dynamic test vehicle model; s3, establishing a deflection pavement mathematical model by using the vehicle-road dynamic response model; s4, selecting a test road section, and obtaining pavement dynamic reaction data and a pavement surface deflection value; s5, constructing a road surface deflection solving framework, performing inversion to obtain a foundation top equivalent rebound modulus, and establishing a road bearing capacity evaluation system; and S6, determining a foundation top equivalent resilience modulus corresponding to the actually measured deflection value according to the pavement dynamic reaction data and the pavement surface deflection value, calculating an asphalt pavement modulus index, and generating a pavement bearing capacity report according to a grading criterion. According to the invention, the combination of multiple factors is realized, and the rapid and accurate test of the bearing capacity of the asphalt concrete pavement is realized by utilizing dynamic test.

Description

Technical Field

[0001] The invention relates to the technical field of pavement bearing capacity testing, and in particular to a method for dynamically testing the bearing capacity of an asphalt concrete pavement. Background Art

[0002] With the continuous growth of road traffic and the increasing number of heavy vehicles, it is particularly important to ensure that asphalt concrete pavements have sufficient bearing capacity to ensure driving safety and extend the service life of roads. However, the traditional evaluation of pavement bearing capacity relies on static test methods or estimates based on empirical formulas. These methods are difficult to accurately reflect the dynamic response characteristics under actual traffic loads, resulting in inaccurate evaluation of the health status of the pavement structure.

[0003] Traditional technical solutions mainly use static loading tests to measure the deformation of the road surface, such as the Beckman beam method. Although this method can give the deflection value of the road surface under certain conditions, it cannot simulate the actual driving state, that is, it fails to take into account the influence of vehicle speed, vehicle dynamics behavior and environmental factors. In addition, traditional methods often require closed traffic for testing, which is complicated and inefficient. In contrast, although some existing dynamic testing technologies take into account some dynamic factors, they are still lacking in comprehensive simulation of vehicle-road interaction, and cannot fully reflect the coupling effect of the vehicle-road system. At the same time, there are limitations in data acquisition accuracy and processing speed.

[0004] The current state of the art addressed by the present invention is that, although some dynamic elements have been introduced into the current road bearing capacity assessment, there is still a lack of a complete framework to integrate the various dynamic responses generated during vehicle driving and how these responses affect the pavement structure. Existing solutions usually focus on single factor analysis, such as focusing only on vehicle load or pavement material properties, while ignoring the interaction between the two. This not only limits the accuracy of the test results, but also makes it difficult for the assessment system to adapt to complex and changeable actual working conditions. Therefore, there is an urgent need for a new test method that can comprehensively consider the impact of vehicle-road interaction.

[0005] In order to solve the problems existing in the prior art, the present invention proposes a new dynamic testing method for the bearing capacity of asphalt concrete pavement. Summary of the invention

[0006] The present invention provides a method for dynamically testing the bearing capacity of an asphalt concrete pavement, comprising:

[0007] S1. Deploy test vehicles, obtain vehicle source data, and build a dynamic test vehicle model;

[0008] S2. Acquire asphalt concrete pavement source data, combine with dynamic test vehicle model, and build vehicle-road dynamic response model;

[0009] S3. Use the vehicle-road dynamic response model to analyze the influence of driving speed, vehicle load, asphalt surface layer properties and base material properties on the road surface deflection, and establish a mathematical model of deflection road surface;

[0010] S4, selecting a test section, setting sensor nodes at the wheel track, and obtaining road surface dynamic response data and road surface deflection values;

[0011] S5. Based on the mathematical model of pavement deflection, a road surface deflection solution framework is constructed in combination with measured data. The equivalent modulus of resilience at the top of the base is obtained through inversion of the road surface deflection solution framework, and a road bearing capacity evaluation system is established.

[0012] S6. Determine the equivalent rebound modulus of the base corresponding to the measured deflection value through the pavement dynamic response data and the pavement surface deflection value, compare the actual measured value with the design value, calculate the asphalt pavement modulus index, and generate a pavement bearing capacity report based on the grading criteria.

[0013] Preferably, the construction of the dynamic test vehicle model includes the following steps:

[0014] S1.1. Install multiple types of sensors on the test vehicle to collect dynamic response data of the vehicle during driving;

[0015] S1.2. Based on the dynamic response data, combined with the static geometric dimensions and mass distribution of the vehicle, a vehicle source database of the static structure and dynamic characteristics of the vehicle is formed;

[0016] S1.3. Based on the vehicle source database, a finite element analysis mechanism is used to create a three-dimensional geometric model of the vehicle, and nodes and unit grids are defined to discretize the bottom contact structure of the vehicle to form a dynamic test vehicle model.

[0017] Preferably, the S1.3 vehicle three-dimensional geometric model simulates the different dynamic response behaviors of a vehicle driving on an asphalt concrete pavement by introducing the vehicle's seven-degree-of-freedom dynamic characteristics, road surface flatness and random load factors. At the same time, the dynamic load transfer function is used to convert the dynamic load generated by the vehicle into a stress distribution acting on the road structure layer, thereby achieving a comprehensive numerical simulation of vehicle-road interaction.

[0018] Preferably, the construction of the vehicle-road dynamic response model includes the following steps:

[0019] S2.1. Deploy multiple types of sensors on the test road section to obtain the stress, strain, temperature and humidity changes of the road surface structure under the vehicle load, and use scanners to record the geometric characteristics of the road surface;

[0020] S2.2. Based on the data collected on site, determine the key mechanical performance parameters of the asphalt surface layer and base material of the road surface, integrate the geometric parameters of the pavement structure as well as the compaction and flatness, and form a database of pavement characteristics;

[0021] S2.3, combining the dynamic test vehicle model with the road surface characteristics database, and obtaining the wheel track distribution on the vehicle's driving path to determine the road surface location where the vehicle load is applied;

[0022] S2.4. Use finite element analysis software to create a three-dimensional geometric model of the pavement structure, define nodes and unit grids to discretize the pavement structure, and apply vehicle loads as input conditions to the three-dimensional geometric model of the pavement structure to form a vehicle-road dynamic response model.

[0023] Preferably, the construction of the mathematical model of the deflection road surface in S3 is carried out by analyzing the driving speed v, the vehicle load F, the elastic modulus E of the asphalt surface layer properties s And the resilience modulus E of the base material properties b The influence of road surface deflection is simulated under different driving speeds and load conditions. The deflection calculation formula of the deflection change is: Where δ represents the road surface deflection value, a is the influence radius, E c is the composite modulus, v is Poisson's ratio, and h is the thickness of the asphalt surface layer; the pavement surface deflection value is embedded in the vehicle-road dynamic response model, and the finite element analysis mechanism is used for numerical solution to obtain the specific deflection response of the pavement surface and form a mathematical model of deflection pavement.

[0024] Preferably, a test section is selected in S4, and sensor nodes are set at the wheel track to obtain road surface dynamic response data and road surface deflection values, specifically including: on the selected test section, high-precision sensor nodes are arranged along the main wheel track positions of the vehicle, including but not limited to deflection meters, strain gauges, accelerometers and displacement sensors; the sensors are used to collect real-time dynamic response data of the road surface under the action of vehicle load, including but not limited to stress, strain, vibration acceleration and displacement changes, and measure the instantaneous deflection value of the road surface before and after the vehicle passes.

[0025] Preferably, the sensor node synchronously records and transmits data via wireless communication, and is equipped with a synchronous marking unit to accurately mark the time and position information of each measurement, thereby obtaining the dynamic response data of the road surface and the surface deflection value at the marked point.

[0026] Preferably, in S5, a road surface deflection solution framework is constructed based on the deflection pavement mathematical model in combination with measured data, specifically including: inputting the measured pavement dynamic response data and surface deflection value into a pre-established deflection pavement mathematical model, comparing the deflection value predicted by the deflection pavement mathematical model with the actually measured deflection value, and using an iterative optimization mechanism to adjust key parameters in the deflection pavement mathematical model, including but not limited to the composite modulus, Poisson's ratio, and asphalt surface thickness, so as to minimize the error between the deflection value predicted by the deflection pavement mathematical model and the actually measured deflection value, thereby forming a solution framework for simulating the deflection response of the pavement under different working conditions.

[0027] Preferably, the base-top equivalent elastic modulus is obtained by inverting the road surface deflection solution framework in S5, and a road bearing capacity evaluation system is established, which specifically includes: inputting the road surface deflection value δ and dynamic response data into the road surface deflection solution framework, and obtaining the base-top equivalent elastic modulus E by inverting the road surface deflection solution framework. t , the formula is: Wherein, F(t) is the vehicle load that changes with time, δ is the calculated deflection value, a is the influence radius, β is the correction coefficient of the asphalt surface layer characteristics, and h is the thickness of the asphalt surface layer; the equivalent elastic modulus E of the base top is calculated by combining the deflection value and the vehicle load data. t ; The E obtained by inversion t The road bearing capacity evaluation system is formed by combining the road bearing capacity index with the design standards and specifications to define the road bearing capacity indicators of different levels.

[0028] Preferably, the S6 determines the measured deflection value δ by using the road surface dynamic response data and the road surface deflection value. s The corresponding equivalent rebound modulus of the base top is compared with the actual measured value and the design value to calculate the modulus index of the asphalt pavement. The formula is: Where M is the asphalt pavement modulus index, E t is the equivalent rebound modulus of the base obtained by inversion, E0 is the design standard rebound modulus, τ is the temperature sensitivity coefficient, ΔT is the temperature difference between the actual measurement and the design conditions, and a pavement bearing capacity report is generated based on the asphalt pavement modulus index M and the preset grading criteria; the pavement bearing capacity report includes but is not limited to the specific parameters of each test section, comparative analysis results and maintenance recommendations.

[0029] Compared with the prior art, the technical solution of this application has the following technical effects:

[0030] The present invention solves the problem that traditional static testing methods cannot simulate the interaction between vehicles and roads under real driving conditions by constructing a dynamic test vehicle model and introducing the vehicle's seven-degree-of-freedom dynamic characteristics, road surface flatness and random load factors. It can fully simulate various dynamic response behaviors of the vehicle during driving, including the stress distribution caused by the vehicle on the road surface, and can more accurately evaluate the bearing capacity of asphalt concrete pavement under actual traffic conditions, providing a more reliable basis for road design and maintenance.

[0031] The present invention solves the problems of inaccurate data collection and difficulty in real-time monitoring in traditional testing methods by deploying multiple types of sensor nodes on the test section and using wireless communication to synchronously record and transmit data, ensuring high-precision acquisition of road surface dynamic response data and surface deflection values, while accurately marking the time and location information of each measurement, realizing real-time monitoring of road conditions, helping to promptly discover potential problems and take corresponding measures, and improving the response speed and service level of road management.

[0032] The present invention solves the problem in the prior art that the prediction results of the model are inconsistent with the actual situation by establishing a mathematical model of the deflection pavement and inputting the measured data into a pre-established solution framework for iterative optimization. The prediction error is minimized by adjusting key parameters such as composite modulus, Poisson's ratio, asphalt surface layer thickness, etc., thereby obtaining a more accurate simulation of the pavement deflection response, enhancing the adaptability and prediction accuracy of the model, providing strong support for the estimation of pavement performance under different working conditions, and further promoting the improvement and development of the road bearing capacity evaluation system.

[0033] The present invention generates a pavement bearing capacity report by calculating the equivalent rebound modulus of the base and comparing it with the design standard, thereby solving the problem that traditional evaluation methods are difficult to quantitatively describe the health status of the road. It combines the deflection value and vehicle load data, and uses an inversion algorithm to calculate indicators reflecting the pavement structure characteristics. Based on this, detailed grading criteria are formulated, providing a scientific and reasonable road bearing capacity evaluation mechanism that can not only accurately determine the current state of the pavement, but also make specific maintenance suggestions based on the analysis results, guide road maintenance work, and effectively extend the service life of the road.

[0034] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application so that it can be implemented in accordance with the contents of the specification, and to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following is a detailed description of the preferred embodiments of the present application in conjunction with the accompanying drawings as follows.

[0035] Based on the detailed description of the specific embodiments of the present application in combination with the accompanying drawings below, those skilled in the art will become more aware of the above and other objects, advantages and features of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings without creative work. In all drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual scale.

[0037] Figure 1 A flow chart of a method for dynamically testing the bearing capacity of an asphalt concrete pavement according to the present invention;

[0038] Figure 2 A dynamic test vehicle model flow chart of a dynamic test method for bearing capacity of an asphalt concrete pavement according to the present invention;

[0039] Figure 3 A flow chart of a vehicle-road dynamic response model of a dynamic test method for bearing capacity of an asphalt concrete pavement according to the present invention;

[0040] Figure 4 A schematic diagram of a method for dynamically testing the bearing capacity of an asphalt concrete pavement according to the present invention;

[0041] Figure 5 A comparison diagram of deflection values ​​of a dynamic test method for bearing capacity of an asphalt concrete pavement according to the present invention;

[0042] Figure 6 This is a comparison chart of the equivalent rebound modulus of the base top of a dynamic testing method for the bearing capacity of an asphalt concrete pavement according to the present invention. DETAILED DESCRIPTION

[0043] To make the purpose, technical scheme and advantages of the embodiment of the present application clearer, the technical scheme in the embodiment of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the present application. Obviously, the described embodiment is a part of the embodiment of the present application, rather than all of the embodiments. In the following description, specific details such as specific configuration and components are provided only to help fully understand the embodiments of the present application. Therefore, it should be clear to those skilled in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. In addition, for clarity and brevity, the description of known functions and structures is omitted in the embodiment.

[0044] It should be understood that the references to "one embodiment" or "this embodiment" throughout the specification mean that the specific features, structures, or characteristics associated with the embodiment are included in at least one embodiment of the present application. Therefore, the references to "one embodiment" or "this embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0045] In addition, the present application may repeat reference numerals and / or letters in different examples. This repetition is for the purpose of simplicity and clarity, and does not in itself indicate the relationship between the various embodiments and / or settings discussed.

[0046] The term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist at the same time. The term " / and" in this article describes another type of association object relationship, indicating that there can be two relationships. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " in this article generally indicates that the previous and next associated objects are in an "or" relationship.

[0047] The term "at least one" in this article is merely a description of the association relationship of associated objects, indicating that there may be three relationships. For example, at least one of A and B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0048] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusions.

[0049] Example 1

[0050] This embodiment mainly describes a method for dynamic testing of the bearing capacity of an asphalt concrete pavement. Figure 1 As shown, including:

[0051] S1. Deploy test vehicles, obtain vehicle source data, and build a dynamic test vehicle model;

[0052] S2. Acquire asphalt concrete pavement source data, combine with dynamic test vehicle model, and build vehicle-road dynamic response model;

[0053] S3. Use the vehicle-road dynamic response model to analyze the influence of driving speed, vehicle load, asphalt surface layer properties and base material properties on the road surface deflection, and establish a mathematical model of deflection road surface;

[0054] S4, selecting a test section, setting sensor nodes at the wheel track, and obtaining road surface dynamic response data and road surface deflection values;

[0055] S5. Based on the mathematical model of pavement deflection, a road surface deflection solution framework is constructed in combination with measured data. The equivalent modulus of resilience at the top of the base is obtained through inversion of the road surface deflection solution framework, and a road bearing capacity evaluation system is established.

[0056] S6. Determine the equivalent rebound modulus of the base corresponding to the measured deflection value through the pavement dynamic response data and the pavement surface deflection value, compare the actual measured value with the design value, calculate the asphalt pavement modulus index, and generate a pavement bearing capacity report based on the grading criteria.

[0057] Further, if Figure 2 As shown, the construction of the dynamic test vehicle model includes the following steps:

[0058] S1.1. Install multiple types of sensors on the test vehicle to collect dynamic response data of the vehicle during driving;

[0059] S1.2. Based on the dynamic response data, combined with the static geometric dimensions and mass distribution of the vehicle, a vehicle source database of the static structure and dynamic characteristics of the vehicle is formed;

[0060] S1.3. Based on the vehicle source database, a finite element analysis mechanism is used to create a three-dimensional geometric model of the vehicle, and nodes and unit grids are defined to discretize the bottom contact structure of the vehicle to form a dynamic test vehicle model.

[0061] Furthermore, the S1.3 vehicle three-dimensional geometric model simulates the different dynamic response behaviors of a vehicle driving on an asphalt concrete pavement by introducing the vehicle's seven-degree-of-freedom dynamic characteristics, road surface roughness, and random load factors. At the same time, the dynamic load transfer function is used to convert the dynamic load generated by the vehicle into a stress distribution acting on the road structure layer, thereby achieving a comprehensive numerical simulation of vehicle-road interaction.

[0062] Further, if Figure 3 As shown in Figure 1, the construction of the vehicle-road dynamic response model includes the following steps:

[0063] S2.1. Deploy multiple types of sensors on the test road section to obtain the stress, strain, temperature and humidity changes of the road surface structure under the vehicle load, and use scanners to record the geometric characteristics of the road surface;

[0064] S2.2. Based on the data collected on site, determine the key mechanical performance parameters of the asphalt surface layer and base material of the road surface, integrate the geometric parameters of the pavement structure as well as the compaction and flatness, and form a database of pavement characteristics;

[0065] S2.3, combining the dynamic test vehicle model with the road surface characteristics database, and obtaining the wheel track distribution on the vehicle's driving path to determine the road surface location where the vehicle load is applied;

[0066] S2.4. Use finite element analysis software to create a three-dimensional geometric model of the pavement structure, define nodes and unit grids to discretize the pavement structure, and apply vehicle loads as input conditions to the three-dimensional geometric model of the pavement structure to form a vehicle-road dynamic response model.

[0067] Further, if Figure 4 As shown in the figure, the mathematical model of the deflection road surface in S3 is constructed by analyzing the driving speed v, vehicle load F, elastic modulus E of the asphalt surface layer properties. s And the resilience modulus E of the base material properties b The influence of road surface deflection is studied by simulating the deflection changes under different driving speeds and load conditions. The deflection calculation formula is: Where δ represents the road surface deflection value, a is the influence radius, E c is the composite modulus, v is Poisson's ratio, and h is the thickness of the asphalt surface layer; the pavement surface deflection value is embedded in the vehicle-road dynamic response model, and the finite element analysis mechanism is used for numerical solution to obtain the specific deflection response of the pavement surface and form a mathematical model of deflection pavement.

[0068] Furthermore, in S4, a test section is selected, and sensor nodes are set at the wheel track to obtain the dynamic response data of the road surface and the deflection value of the road surface, which specifically includes: on the selected test section, high-precision sensor nodes are arranged along the main wheel track of the vehicle, including but not limited to deflection meters, strain gauges, accelerometers and displacement sensors; the sensors are used to collect real-time dynamic response data of the road surface under the action of vehicle load, including but not limited to stress, strain, vibration acceleration and displacement changes, and measure the instantaneous deflection value of the road surface before and after the vehicle passes.

[0069] Furthermore, the sensor nodes synchronously record and transmit data through wireless communication, and are equipped with a synchronous marking unit to accurately mark the time and location information of each measurement, thereby obtaining the dynamic response data of the road surface and the surface deflection value at the marked point.

[0070] Furthermore, in S5, a road surface deflection solution framework is constructed based on the deflection pavement mathematical model and combined with measured data, specifically including: inputting the measured pavement dynamic response data and surface deflection value into a pre-established deflection pavement mathematical model, comparing the deflection value predicted by the deflection pavement mathematical model with the actually measured deflection value, and using an iterative optimization mechanism to adjust key parameters in the deflection pavement mathematical model, including but not limited to the composite modulus, Poisson's ratio, and asphalt surface thickness, so as to minimize the error between the deflection value predicted by the deflection pavement mathematical model and the actually measured deflection value, thereby forming a solution framework for simulating the deflection response of the road surface under different working conditions.

[0071] Furthermore, in S5, the equivalent elastic modulus of the top of the base is obtained by inverting the road surface deflection solution framework, and a road bearing capacity evaluation system is established, which specifically includes: inputting the road surface deflection value δ and dynamic response data into the road surface deflection solution framework, and obtaining the equivalent elastic modulus of the top of the base E by inverting the road surface deflection solution framework. t , the formula is: Where F(t) is the vehicle load that changes with time, δ is the calculated deflection value, a is the influence radius, β is the correction factor of the asphalt surface layer characteristics, and h is the thickness of the asphalt surface layer. By combining the deflection value and vehicle load data, the equivalent elastic modulus of the base top E is calculated. t ; According to the inversion of E t The road bearing capacity evaluation system is formed by combining the road bearing capacity index with the design standards and specifications to define the road bearing capacity indicators of different levels.

[0072] Further, S6 determines the measured deflection value δ by using the pavement dynamic response data and the pavement surface deflection value. s The corresponding equivalent rebound modulus of the base top is compared with the actual measured value and the design value to calculate the modulus index of the asphalt pavement. The formula is: Where M is the asphalt pavement modulus index, E t is the equivalent rebound modulus of the base obtained by inversion, E0 is the design standard rebound modulus, τ is the temperature sensitivity coefficient, ΔT is the temperature difference between the actual measurement and the design conditions. According to the asphalt pavement modulus index M and the preset grading criteria, a pavement bearing capacity report is generated; the pavement bearing capacity report includes but is not limited to the specific parameters of each test section, comparative analysis results and maintenance recommendations.

[0073] This embodiment constructs a vehicle-road dynamic response model to simultaneously consider multiple factors such as driving speed, vehicle load, asphalt surface properties and base material performance, thereby improving the authenticity and reliability of the test results. It uses high-precision sensors to collect road surface dynamic response data in real time, combines advanced finite element analysis technology and iterative optimization mechanisms, and establishes a road bearing capacity assessment system that can invert the base-top equivalent rebound modulus, thereby improving the level of intelligent road management.

[0074] Example 2

[0075] This embodiment describes in detail a classification criterion for a dynamic test method for bearing capacity of an asphalt concrete pavement. Figure 3 As shown, it specifically includes classification criteria and pavement bearing capacity report generation;

[0076] By comparing the actual measured value with the design value, the asphalt pavement modulus index is calculated, and a pavement bearing capacity report is generated based on this index and the preset grading criteria; the grading criteria are set to define the road bearing capacity grade based on different ranges of the asphalt pavement modulus index (MI), and the asphalt pavement modulus index is divided into multiple types of intervals, each of which corresponds to a specific road bearing capacity level, from best to worst, namely A, B, C, and D; this not only helps to intuitively understand the current bearing condition of the pavement, but also facilitates the formulation of corresponding maintenance strategies.

[0077] For pavements with a higher modulus index, that is, Class A pavements, this type of pavement shows excellent bearing capacity and structural stability. Its modulus index far exceeds the design standard, indicating that the road section can withstand the expected traffic flow and has a long service life. In the pavement bearing capacity report, for Class A pavements, its good performance is emphasized, and regular monitoring is recommended to maintain the status quo. At the same time, it is pointed out that the road section does not require large-scale repairs or reconstruction work in the future, thereby optimizing resource allocation and reducing unnecessary maintenance costs.

[0078] When the modulus index of asphalt pavement is in the middle range, such as Class B and Class C, it means that the bearing capacity of these road sections is between good and fair. For Class B pavements, although they can still effectively support the existing traffic load, they are close to the design limit, and it is necessary to pay close attention to their changing trends and consider implementing preventive maintenance measures; for Class C pavements, since their modulus index is already lower than the design value, showing certain signs of degradation, the report will recommend more frequent inspections and appropriate reinforcement treatments to prevent further deterioration and ensure driving safety.

[0079] For Class D pavement with a low modulus index, it means that the load-bearing capacity of the road section has dropped significantly and cannot meet the current traffic demand. It may have already been significantly damaged or deformed. In this case, the pavement load-bearing capacity report will clearly indicate that immediate action must be taken, such as arranging emergency repairs or renovation projects. In addition, the report will also list specific maintenance recommendations in detail, including priority areas, required repair techniques, and expected improvement effects.

[0080] This embodiment describes in detail the grading criteria of the pavement bearing capacity dynamic testing method, which not only achieves efficient guided operation but also ensures that all relevant parties can make timely and accurate decisions based on clear grading criteria to maintain the overall health of the road system.

[0081] Example 3

[0082] This embodiment, based on Embodiment 1, describes in detail a verification method for dynamic testing of bearing capacity of asphalt concrete pavement, specifically including:

[0083] Assume that a main road in a city (hereinafter referred to as the "target road section") faces the need to evaluate the health status of the road structure under the conditions of heavy daily traffic volume and frequent heavy vehicle traffic. The road section is evaluated using the traditional static test method and the dynamic test method in this application;

[0084] The target road section is 10 kilometers long and has an average daily traffic volume of about 30,000 vehicles, including about 20% heavy trucks. As the road section has been subjected to high loads for a long time, the management department decided to evaluate its load-bearing capacity to determine whether maintenance or repair work is needed. Two independent tests were conducted using the traditional static Beckmann beam method and the dynamic test method of this application.

[0085] Traditional static test method: Using the Beckman beam method, a static loading test was conducted on the target road section after closing the traffic during off-peak hours. The results showed that the average pavement deflection value was 0.81 mm, and the base-top equivalent elastic modulus calculated according to the empirical formula was 50.7 MPa. However, this method fails to take into account the dynamic changes of vehicle loads under actual driving conditions and their impact on the pavement, and may therefore underestimate the degree of pavement damage in real situations.

[0086] Dynamic test method of the present application: Using the dynamic test method of the present application, under normal traffic conditions, high-precision sensor nodes are arranged along the main wheel track position, including deflection meters, strain gauges, accelerometers and displacement sensors. The sensors collect the dynamic response data of the road surface under the vehicle load in real time, such as stress, strain, vibration acceleration and displacement changes, and measure the instantaneous deflection value of the road surface before and after the vehicle passes; after data analysis, it is found that when the average driving speed is 60km / h, the measured deflection value reaches 1.24mm, and the equivalent rebound modulus of the base top obtained by inversion is 42.3MPa. In addition, the asphalt pavement modulus index MI=0.75 is calculated (assuming that the standard rebound modulus given by the design is 53.3MPa, the temperature sensitivity coefficient is 1.0, and the temperature difference between the actual measurement and the design conditions is 0℃). According to the classification criteria, the road section is rated as Class C, indicating that its bearing capacity is close to the critical state.

[0087] Table 1 Comparative analysis table

[0088]

[0089] As shown in Table 1, it can be seen from the above data comparison that the results obtained by the traditional static test method are relatively optimistic; Figure 4-Figure 5 As shown in the figure, it can be concluded that the static test method has a fixed deflection value of about 0.81 mm; the dynamic test method deflection value curve shows that the deflection value gradually increases with the increase of driving speed, especially after the speed exceeds 40 km / h, the growth trend is more obvious; the static Beckmann beam method base top equivalent rebound modulus curve shows that the rebound modulus remains around 50.7 MPa, and the dynamic test method base top equivalent rebound modulus curve shows that the dynamic test method shows that the rebound modulus fluctuates with time and vehicle driving conditions. At higher driving speeds, the rebound modulus drops to about 42.3 MPa, reflecting the impact of actual traffic load on pavement structure. The dynamic test method of this application more accurately reflects the bearing capacity of the target section under actual traffic conditions.

[0090] At the same time, the dynamic testing method according to the present application takes into account various factors under actual driving conditions, avoids the errors that may be caused by static testing, and provides a more realistic road performance evaluation; dynamic testing can be completed without closing traffic, and realizes real-time monitoring of road conditions, which helps to detect problems in a timely manner and take measures.

[0091] In this embodiment, by calculating the modulus index of the asphalt pavement and combining it with the grading criteria, the dynamic testing method can not only quantitatively describe the health status of the pavement, but also provide a scientific basis for subsequent maintenance strategies to ensure the effective use of resources. Accurate evaluation results can help formulate reasonable maintenance plans, thereby effectively extending the service life of the road and reducing long-term maintenance costs. The dynamic testing method provided has demonstrated significant technical superiority in evaluating the bearing capacity of asphalt concrete pavements, bringing a more intelligent and precise solution to road management.

[0092] The above are only preferred embodiments of the present invention, which do not limit the scope of protection of the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any changes, modifications, replacements, integrations and parameter changes to these embodiments within the spirit and principles of the present invention through conventional substitutions or without departing from the principles and spirit of the present invention fall within the scope of protection of the present invention.

Claims

1. A dynamic test method for bearing capacity of asphalt concrete pavement, characterized in that: include: S1. Deploy test vehicles, obtain vehicle source data, and build a dynamic test vehicle model; S2. Acquire asphalt concrete pavement source data, combine with dynamic test vehicle model, and build vehicle-road dynamic response model; S3. Use the vehicle-road dynamic response model to analyze the influence of driving speed, vehicle load, asphalt surface layer properties and base material properties on the road surface deflection, and establish a mathematical model of deflection road surface; S4, selecting a test section, setting sensor nodes at the wheel track, and obtaining road surface dynamic response data and road surface deflection values; S5. Based on the mathematical model of pavement deflection, a road surface deflection solution framework is constructed in combination with measured data. The equivalent modulus of resilience at the top of the base is obtained through inversion of the road surface deflection solution framework, and a road bearing capacity evaluation system is established. S6. Determine the equivalent rebound modulus of the base corresponding to the measured deflection value through the pavement dynamic response data and the pavement surface deflection value, compare the actual measured value with the design value, calculate the asphalt pavement modulus index, and generate a pavement bearing capacity report based on the grading criteria.

2. A dynamic testing method for bearing capacity of asphalt concrete pavement according to claim 1, characterized in that: The construction of the dynamic test vehicle model includes the following steps: S1.

1. Install multiple types of sensors on the test vehicle to collect dynamic response data of the vehicle during driving; S1.

2. Based on the dynamic response data, combined with the static geometric dimensions and mass distribution of the vehicle, a vehicle source database of the static structure and dynamic characteristics of the vehicle is formed; S1.

3. Based on the vehicle source database, a finite element analysis mechanism is used to create a three-dimensional geometric model of the vehicle, and nodes and unit grids are defined to discretize the bottom contact structure of the vehicle to form a dynamic test vehicle model.

3. A dynamic testing method for bearing capacity of asphalt concrete pavement according to claim 2, characterized in that: The S1.3 vehicle three-dimensional geometric model simulates the different dynamic response behaviors of a vehicle driving on an asphalt concrete pavement by introducing the vehicle's seven-degree-of-freedom dynamic characteristics, road surface roughness, and random load factors. At the same time, the dynamic load transfer function is used to convert the dynamic load generated by the vehicle into a stress distribution acting on the road structure layer, thereby achieving a comprehensive numerical simulation of vehicle-road interaction.

4. A dynamic testing method for bearing capacity of asphalt concrete pavement according to claim 1, characterized in that: The construction of the vehicle-road dynamic response model includes the following steps: S2.

1. Deploy multiple types of sensors on the test road section to obtain the stress, strain, temperature and humidity changes of the road surface structure under the vehicle load, and use scanners to record the geometric characteristics of the road surface; S2.

2. Based on the data collected on site, determine the key mechanical performance parameters of the asphalt surface layer and base material of the road surface, integrate the geometric parameters of the pavement structure as well as the compaction and flatness, and form a database of pavement characteristics; S2.3, combining the dynamic test vehicle model with the road surface characteristics database, and obtaining the wheel track distribution on the vehicle's driving path to determine the road surface location where the vehicle load is applied; S2.

4. Use finite element analysis software to create a three-dimensional geometric model of the pavement structure, define nodes and unit grids to discretize the pavement structure, and apply vehicle loads as input conditions to the three-dimensional geometric model of the pavement structure to form a vehicle-road dynamic response model.

5. The method for dynamic testing of bearing capacity of asphalt concrete pavement according to claim 1, characterized in that: The construction of the mathematical model of the deflection road surface in S3 is carried out by analyzing the driving speed v, vehicle load F, elastic modulus E of the asphalt surface layer properties s And the resilience modulus E of the base material properties b The influence of road surface deflection is simulated under different driving speeds and load conditions. The deflection calculation formula of the deflection change is: Where δ represents the road surface deflection value, a is the influence radius, E c is the composite modulus, ν is Poisson's ratio, and h is the thickness of the asphalt surface layer. The pavement surface deflection value is embedded in the vehicle-road dynamic response model, and the finite element analysis mechanism is used for numerical solution to obtain the specific deflection response of the pavement surface and form a deflection pavement mathematical model.

6. A dynamic testing method for bearing capacity of asphalt concrete pavement according to claim 1, characterized in that: In the S4, a test section is selected, and sensor nodes are set at the wheel track to obtain the dynamic response data of the road surface and the deflection value of the road surface, which specifically includes: on the selected test section, high-precision sensor nodes are arranged along the main wheel track position of the vehicle, including but not limited to deflection meters, strain gauges, accelerometers and displacement sensors; the sensors are used to collect the dynamic response data of the road surface under the action of vehicle load in real time, including but not limited to stress, strain, vibration acceleration and displacement changes, and measure the instantaneous deflection value of the road surface before and after the vehicle passes.

7. A dynamic testing method for bearing capacity of asphalt concrete pavement according to claim 6, characterized in that: The sensor node synchronously records and transmits data through wireless communication, and is equipped with a synchronous marking unit to accurately mark the time and position information of each measurement, thereby obtaining the dynamic response data of the road surface and the surface deflection value at the marked point.

8. A dynamic testing method for bearing capacity of asphalt concrete pavement according to claim 1, characterized in that: In the S5, a road surface deflection solution framework is constructed based on the deflection pavement mathematical model in combination with measured data, specifically including: inputting the measured pavement dynamic response data and surface deflection value into a pre-established deflection pavement mathematical model, comparing the deflection value predicted by the deflection pavement mathematical model with the actually measured deflection value, and using an iterative optimization mechanism to adjust key parameters in the deflection pavement mathematical model, including but not limited to the composite modulus, Poisson's ratio, and asphalt surface thickness, so as to minimize the error between the deflection value predicted by the deflection pavement mathematical model and the actually measured deflection value, thereby forming a solution framework for simulating the deflection response of the road surface under different working conditions.

9. A method for dynamic testing of bearing capacity of asphalt concrete pavement according to claim 1 or 8, characterized in that: In S5, the equivalent elastic modulus of the top of the base is obtained by inverting the road surface deflection solution framework, and a road bearing capacity evaluation system is established, which specifically includes: inputting the road surface deflection value δ and dynamic response data into the road surface deflection solution framework, and obtaining the equivalent elastic modulus of the top of the base by inverting the road surface deflection solution framework. t , the formula is: Wherein, F(t) is the vehicle load that changes with time, δ is the calculated deflection value, a is the influence radius, β is the correction coefficient of the asphalt surface layer characteristics, and h is the thickness of the asphalt surface layer; the equivalent elastic modulus E of the base top is calculated by combining the deflection value and the vehicle load data. t ; The E obtained by inversion t The road bearing capacity evaluation system is formed by combining the road bearing capacity index with the design standards and specifications to define the road bearing capacity indicators of different levels.

10. A method for dynamic testing of bearing capacity of asphalt concrete pavement according to claim 6, characterized in that: S6 determines the measured deflection value δ by using the road surface dynamic response data and the road surface deflection value s The corresponding equivalent rebound modulus of the base top is compared with the actual measured value and the design value to calculate the modulus index of the asphalt pavement. The formula is: Where M is the asphalt pavement modulus index, E t is the equivalent rebound modulus of the base obtained by inversion, E0 is the design standard rebound modulus, τ is the temperature sensitivity coefficient, ΔT is the temperature difference between the actual measurement and the design conditions, and a pavement bearing capacity report is generated based on the asphalt pavement modulus index M and the preset grading criteria; the pavement bearing capacity report includes but is not limited to the specific parameters of each test section, comparative analysis results and maintenance recommendations.

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