A multi-scale multi-level evaluation method for VOCs emission characteristics of asphalt pavement materials

Abstract

The application provides a kind of asphalt pavement material VOCs emission characteristic cross-scale multilevel evaluation method, it is related to the technical field of road environment analysis, method includes: based on the preset evaluation device, under the simulation of typical road conditions, carry out VOCs emission concentration detection to multiscale sample set, and VOCs emission concentration data are analyzed under multilevel perspective, to form the multilevel concentration data set corresponding to different scale asphalt pavement material;Based on multilevel concentration data set, the VOCs emission behavior of different scale asphalt pavement material is uniformly described, so as to obtain VOCs emission characteristic representation result;Based on VOCs emission characteristic representation result, the VOCs emission law between different scale asphalt pavement material is associated analysis, so as to complete the cross-scale comprehensive analysis and evaluation of asphalt-based material VOCs emission characteristic.The application can consider emission rate, total amount and other dynamic and comprehensive factors, improve the accuracy of asphalt pavement material VOCs emission characteristic evaluation.

Description

Technical Field

[0001] This invention relates to the technical field of road environment analysis, specifically to a multi-scale, multi-level evaluation method for VOCs emission characteristics of asphalt pavement materials. Background Technology

[0002] Asphalt pavement, due to its excellent durability, driving performance, and economical maintenance, has been widely used in transportation infrastructure such as highways, urban roads, and expressways. With the rapid development of global transportation infrastructure construction, especially in urban areas, asphalt pavement has become the primary paving method. However, the asphalt paving process is accompanied by significant environmental pollution, particularly the release of large amounts of volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), and other harmful gases. These pollutants can form ozone and fine particulate matter (PM2.5) through photochemical reactions, posing a serious threat to air quality, public health, and ecosystem stability.

[0003] Current research on VOC emissions from asphalt-based materials largely focuses on measuring emission concentrations. This involves evaluating the material's emission characteristics by detecting the concentration of volatile organic compounds in the released gases at specific temperatures or operating conditions. However, using emission concentration alone as an evaluation indicator typically only reflects the emission status at a specific moment or within a short time interval, failing to reveal the dynamic release patterns of VOCs during actual construction. Because asphalt materials undergo continuous temperature changes and temporal evolution during mixing, transportation, paving, and compaction, the VOC release process is simultaneously influenced by multiple factors, including material composition, structural dimensions, and environmental conditions. Therefore, a single concentration indicator cannot comprehensively characterize the material's emission behavior at different stages. Without analysis of comprehensive indicators such as emission rates and total emissions, it is difficult to accurately assess the true emission levels of asphalt-based materials throughout the entire construction activity, and it also hinders the objective comparison and scientific evaluation of the environmental impact of different material systems. Summary of the Invention

[0004] This invention provides a multi-scale, multi-level evaluation method for VOCs emission characteristics of asphalt pavement materials, which can consider dynamic and comprehensive factors such as emission rate and total amount, thereby improving the accuracy of VOCs emission characteristic evaluation of asphalt pavement materials.

[0005] In a first aspect of the present invention, a multi-scale, multi-level method for evaluating the VOC emission characteristics of asphalt pavement materials is provided, the method comprising: Based on the pre-set evaluation device, VOCs emission concentration was detected on a multi-scale sample set under simulated typical road conditions. The VOCs emission concentration data were analyzed at three levels: total concentration, component concentration, and individual substance concentration, in order to form a multi-level concentration data set corresponding to asphalt pavement materials at different scales. Based on the multi-level concentration data set, the VOCs emission behavior of asphalt pavement materials at different scales is uniformly characterized, thereby obtaining the VOCs emission characteristic characterization results corresponding to the asphalt pavement materials at each scale. Based on the VOCs emission characteristics characterization results, a correlation analysis was conducted on the VOCs emission patterns among asphalt pavement materials at different scales, thereby completing a cross-scale comprehensive analysis and evaluation of the VOCs emission characteristics of asphalt-based materials.

[0006] Based on the above technical solutions, preferably, the preset evaluation device includes... The equipment includes a chassis, a heating oil bath disposed inside the chassis, and an oil inlet and an oil outlet communicating with the heating oil bath, wherein: The heated oil bath is equipped with a sample plate for supporting the asphalt pavement material. Heating and cooling pipes for adjusting the oil bath temperature are installed inside the heated oil bath. A heat dissipation strip assembly is provided above the heating oil bath to ensure that heat is evenly transferred to the sample plate. A temperature controller is installed on the chassis to adjust the internal temperature of the heating oil bath, so as to create a controlled heating environment for the asphalt pavement material together with the sample plate.

[0007] Based on the above technical solutions, preferably, the preset evaluation device also includes Includes a sealing cover covering the sample plate, the sealing cover and the chassis forming a closed test space, and an air inlet for introducing gas into the closed test space is provided on the side wall of the sealing cover; A regulating valve for adjusting the gas flow rate is provided on the air inlet; A sampling port connected to the closed test space is provided on the top of the sealing cover. The gas flow channel for collecting VOCs samples of asphalt pavement material is formed by the air inlet, the regulating valve and the sampling port. This enables the preset evaluation device to collect and detect the VOCs released by the asphalt pavement material under the controlled heating environment.

[0008] Based on the above technical solutions, preferably, the step of uniformly characterizing the VOCs emission behavior of asphalt pavement materials at different scales based on the multi-level concentration data set specifically includes: Under simulated temperature conditions, the asphalt pavement material at different scales is heated to obtain VOCs emission concentration data corresponding to the asphalt pavement material at each scale, thereby forming an emission concentration data set. The simulated temperature conditions are constructed in the test environment based on the construction characteristics of the asphalt pavement construction project. Based on the emission concentration data set, the emission rate data of each VOCs substance under the conditions of unit time and unit asphalt mass are calculated to form an emission rate data set; Based on the emission rate data set, the emission amount of each VOCs substance within the monitoring time range is calculated to form an emission data set. The VOCs substances are then classified into components according to their chemical structure characteristics and chemical bond types, so that VOCs substances belonging to the same component form a component set. The emission data of each VOCs substance in the component set is accumulated to obtain the component emission data. At the same time, the component emission data obtained under different temperature conditions are summarized and accumulated to obtain the total VOCs emission data during the asphalt pavement construction stage. Based on the emission concentration data set, the emission rate data set, and the total VOCs emission data, and combined with four scales (asphalt, asphalt mastic, asphalt mortar, and asphalt mixture) and three levels (total concentration, component concentration, and monomer concentration), the VOCs emission behavior of asphalt pavement materials is uniformly characterized to form VOCs emission characteristic representation results of emission concentration, emission rate, and total emission.

[0009] Based on the above technical solutions, preferably, before uniformly characterizing the VOCs emission behavior of asphalt pavement materials at different scales based on the multi-level concentration data set, thereby obtaining the VOCs emission characteristic characterization results corresponding to the asphalt pavement materials at each scale, the method further includes: The multi-scale sample set is constructed using uniform asphalt quality as the test benchmark. Under the uniform asphalt quality benchmark, asphalt concrete is constructed into compacted asphalt concrete samples and loose asphalt concrete samples. The compacted asphalt concrete samples are prepared with a regular geometric structure that matches the sample plate of the heated oil bath to ensure uniform heating. At the same time, the loose asphalt concrete samples are uniformly spread on the surface of the bearing carrier under uniform quality conditions. Under the unified asphalt quality benchmark, the amount of asphalt in the asphalt mortar is determined according to the asphalt-aggregate ratio of the asphalt concrete, and compacted asphalt mortar samples and loose asphalt mortar samples are constructed. The compacted asphalt mortar samples maintain the same compacted structure as the compacted asphalt concrete samples, while the loose asphalt mortar samples are spread on the surface of the bearing carrier under the same quality conditions. Under the unified asphalt quality standard, the ratio of asphalt to mineral powder in asphalt mastic is determined according to the asphalt-aggregate ratio and the powder-binder ratio, and the asphalt mastic is prepared into a thin film structure to form an asphalt mastic sample. The amount of asphalt sample used is determined under the unified asphalt quality standard, and the asphalt sample is prepared as a thin film structure, thereby forming a multi-scale sample set covering asphalt, asphalt mastic, asphalt mortar and asphalt concrete under the unified asphalt quality standard.

[0010] Based on the above technical solutions, preferably, the step of using a preset testing device to detect VOC emission concentrations on a multi-scale sample set under simulated typical road conditions specifically includes: The asphalt pavement materials of different sizes are placed sequentially on the sample plate, so that the asphalt pavement materials are in contact with the heated surface of the sample plate; The target temperature of the oil bath medium inside the heating oil bath is set by the temperature controller, and the heating tube is driven by the temperature controller to increase the temperature of the oil bath medium. The heat dissipation strips are arranged to achieve uniform heat transfer between the heating oil bath and the sample plate, thereby creating a stable and uniform heating environment for the sample plate. Gas is introduced into the closed test space formed by the sealing cover and the chassis through the air inlet, and the gas flow rate is regulated by the regulating valve set on the air inlet to form a stable displacement atmosphere inside the closed test space. At the same time, the sampling port set on the top of the sealing cover is kept in the gas collection state to form a gas flow channel for exporting VOCs released from asphalt pavement materials. Under the condition of forming a stable displacement atmosphere in the closed test space, the asphalt pavement material continuously releases VOCs under the heating effect of the sample plate. Under the condition of continuous gas supply at the air inlet and gas flow control by the regulating valve, the gas inside the closed test space maintains continuous flow and stable displacement, thereby forming a dynamic gas environment for the released VOCs in the closed test space. The gas inside the closed test space is extracted through the sampling port to obtain a VOCs gas sample released by the asphalt pavement material under the current heating conditions.

[0011] Based on the above technical solutions, preferably, the step of calculating the emission rate data of each VOCs substance under unit time and unit asphalt mass conditions based on the emission concentration data set to form an emission rate data set specifically includes: The emission concentration data of the same VOCs substance obtained from each sampling are averaged to obtain the average emission concentration data within the monitoring time range. The average emission concentration data is multiplied by the VOCs emission volume per unit monitoring time under the simulated temperature environment to obtain the emission data of VOCs under the unit time condition. The emission data is then compared with the mass of asphalt material tested under the simulated temperature environment to obtain the emission rate data of the VOCs under the conditions of unit time and unit mass of asphalt, thereby forming the emission rate data set.

[0012] In a second aspect of the invention, a multi-scale, multi-level assessment device for VOCs emission characteristics of asphalt pavement materials is provided. The device is used to perform a multi-scale, multi-level assessment method for VOCs emission characteristics of asphalt pavement materials as described in any of the above-described methods. The device includes an acquisition module, a processing module, and an output module, wherein: The acquisition module is used to detect VOCs emission concentrations on a multi-scale sample set under simulated typical road conditions based on a preset evaluation device, and to analyze the VOCs emission concentration data at three levels: total concentration, component concentration, and individual substance concentration, so as to form a multi-level concentration data set corresponding to asphalt pavement materials at different scales. The processing module is used to uniformly characterize the VOCs emission behavior of asphalt pavement materials at different scales based on the multi-level concentration data set, thereby obtaining the VOCs emission characteristic characterization results corresponding to the asphalt pavement materials at each scale. The output module is used to perform correlation analysis on the VOCs emission patterns among asphalt pavement materials at different scales based on the VOCs emission characteristic characterization results, thereby completing the cross-scale comprehensive analysis and evaluation of the VOCs emission characteristics of asphalt-based materials.

[0013] In a third aspect of the invention, an electronic device is provided, including a processor, a memory, a user interface, and a network interface, wherein the memory is used to store instructions, the user interface and the network interface are both used to communicate with other devices, and the processor is used to execute the instructions stored in the memory to cause the electronic device to perform the method as described in any of the preceding embodiments.

[0014] In a fourth aspect of the invention, a non-transitory computer-readable storage medium is provided, the computer-readable storage medium storing instructions that, when executed, perform the method as described in any of the preceding claims.

[0015] In summary, one or more technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages: This invention, under simulated typical road surface conditions, acquires VOC emission concentration data of multi-scale sample sets during the heating process using a pre-set testing device. The emission concentration data is analyzed at multiple levels, including total concentration, component concentration, and monomer concentration. Based on this, the emission rate per unit time and per unit mass of asphalt is calculated, and the total emission is accumulated. This allows the characterization of emission features to consider not only instantaneous concentration information but also changes in release intensity and the cumulative effect over time during temperature variations. Furthermore, by uniformly characterizing emission concentration, emission rate, and total emission at multiple material scales (asphalt, asphalt mastic, asphalt mortar, and asphalt mixtures) and performing correlation analysis, the influence of material composition differences, temperature evolution, and chemical component distribution on VOC emission behavior can be comprehensively reflected. This enables the evaluation of VOC emission characteristics of asphalt pavement materials to simultaneously cover instantaneous emission states, dynamic release processes, and overall emission levels, improving the completeness of emission characteristic analysis and the accuracy of evaluation results. Attached Figure Description

[0016] Figure 1 This is a flowchart illustrating a multi-scale, multi-level evaluation method for VOCs emission characteristics of asphalt pavement materials disclosed in an embodiment of the present invention. Figure 2 This is a schematic diagram of a preset evaluation device disclosed in an embodiment of the present invention; Figure 3 This is a schematic diagram of a multi-scale, multi-level evaluation device for VOCs emission characteristics of asphalt pavement materials disclosed in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of an electronic device disclosed in an embodiment of the present invention.

[0017] Explanation of reference numerals in the attached drawings: 201, chassis; 202, heated oil bath; 203, oil inlet; 204, oil drain; 205, sealing cap; 206, temperature controller; 207, air inlet; 208, sampling port; 209, sample plate; 210, heating element; 211, cooling element; 212, heat dissipation strip assembly; 213, temperature sensor; 301, acquisition module; 302, processing module; 303, output module; 401, processor; 402, communication bus; 403, user interface; 404, network interface; 405, memory. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0019] In the description of the embodiments of the present invention, words such as "for example" or "for instance" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "for example" or "for instance" in the embodiments of the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Rather, the use of words such as "for example" or "for instance" is intended to present the relevant concepts in a specific manner.

[0020] In the description of the embodiments of the present invention, the term "multiple" means two or more. For example, multiple systems means two or more systems, and multiple screen terminals means two or more screen terminals. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. The terms "comprising," "including," "having," and variations thereof all mean "including but not limited to," unless otherwise specifically emphasized.

[0021] Asphalt pavement is widely used in highways and urban transportation infrastructure, but it releases a large amount of volatile organic compounds and other harmful gases during construction, which affects the atmospheric environment and public health. Existing studies mostly evaluate the emission characteristics of asphalt-based materials by detecting VOCs emission concentrations at specific temperatures or operating conditions. However, a single concentration index can only reflect the emission status in a short period of time and is difficult to reveal the dynamic release pattern of asphalt materials during construction as temperature changes and time evolves. Therefore, without comprehensive analysis of emission rates and total emissions, it is difficult to fully reflect the actual emission behavior of asphalt-based materials at the construction activity level and to accurately evaluate the environmental impact of different material systems.

[0022] This embodiment discloses a multi-scale, multi-level evaluation method for VOCs emission characteristics of asphalt pavement materials, referring to... Figure 1 This includes the following steps S110-S130: This invention discloses a multi-scale, multi-level assessment method for VOCs emission characteristics of asphalt pavement materials, which is applied to a server. The server includes, but is not limited to, electronic devices such as mobile phones, tablets, wearable devices, and PCs (Personal Computers), and can also be a backend server running the multi-scale, multi-level assessment method for VOCs emission characteristics of asphalt pavement materials. The server can be implemented using a standalone server or a server cluster composed of multiple servers.

[0023] S110, based on a pre-set testing device, conducts VOCs emission concentration detection on a multi-scale sample set under simulated typical road conditions, and analyzes the VOCs emission concentration data at three levels: total concentration, component concentration, and individual substance concentration, in order to form a multi-level concentration data set corresponding to asphalt pavement materials at different scales.

[0024] In one possible implementation, refer to Figure 2 The preset testing device includes a chassis 201, a heating oil bath 202 disposed inside the chassis 201, and an oil inlet 203 and an oil outlet 204 connected to the heating oil bath 202. The heating oil bath 202 is equipped with a sample plate 209 for supporting asphalt pavement material. Inside the heating oil bath 202 are heating pipes 210 and cooling pipes 211 for adjusting the oil bath temperature. Above the heating oil bath 202 are heat dissipation strips 212 for uniformly transferring heat to the sample plate 209. A temperature controller 206 is disposed on the chassis 201 for adjusting the internal temperature of the heating oil bath 202, so that the heating oil bath 202 and the sample plate 209 together construct a controlled heating environment for the asphalt pavement material.

[0025] Furthermore, the preset testing device also includes a sealing cover 205 covering the sample plate 209. The sealing cover 205 and the casing 201 form a closed testing space. An air inlet 207 for introducing gas into the closed testing space is provided on the side wall of the sealing cover 205. A regulating valve for adjusting the gas flow rate is provided on the air inlet 207. A sampling port 208 communicating with the closed testing space is provided on the top of the sealing cover 205. The air inlet 207, the regulating valve and the sampling port 208 together form a gas flow channel for collecting VOCs samples of asphalt pavement materials, so that the preset testing device can collect and detect VOCs released from asphalt pavement materials under a controlled heating environment.

[0026] Specifically, the pre-designed testing device integrates a heating oil bath 202, an oil inlet 203, and an oil outlet 204 connected to the heating oil bath 202 within a chassis 201, forming an overall testing structure. The chassis 201 serves as the external load-bearing and supporting structure of the device, providing overall fixation and protection for the internal testing components and offering a stable installation space for the heating oil bath 202. The heating oil bath 202, located inside the chassis 201, is the core heating component, containing a heat-conducting oil medium that facilitates uniform heat transfer throughout the space. The oil inlet 203 replenishes the heating oil bath 202 with the heat-conducting oil medium, creating a stable oil bath environment. The oil outlet 204 drains the oil bath medium during maintenance or oil replacement, ensuring long-term stable operation of the device. This structure forms a controllable oil bath heating system, allowing asphalt pavement materials of different scales to undergo heating tests under uniform thermal conditions, thus providing stable thermal field conditions for the subsequent volatile organic compound (VOC) release process. The above-mentioned structure forms an important basis for simulating the temperature environment of asphalt pavement construction in the laboratory.

[0027] A sample plate 209 for supporting asphalt pavement material is set on top of the heating oil bath 202. The sample plate 209 is a heated component that directly contacts the asphalt pavement material sample, and its function is to uniformly transfer heat from the oil bath environment to the asphalt pavement material sample. The sample plate 209 is typically made of a metal material with good thermal conductivity, such as aluminum alloy or stainless steel, to improve heat transfer efficiency and reduce local temperature gradients. When asphalt pavement material samples of different sizes are placed on the sample plate 209, the sample plate 209 provides a stable bearing surface, ensuring full contact between the asphalt pavement material sample and the heated surface, thereby guaranteeing that each sample receives consistent heat input during the heating process. Through this structure of the sample plate 209, materials of different sizes, such as asphalt, asphalt adhesive, asphalt mortar, and asphalt concrete, are subjected to uniform heating conditions during testing, thereby improving the comparability of test data between different materials.

[0028] A heating tube 210 and a cooling tube 211 are installed inside the heated oil bath 202. The heating tube 210 serves as the main heating component, heating the oil bath medium electrically to gradually raise its temperature to a preset range. The cooling tube 211 acts as a temperature regulating component. When it is necessary to lower the oil bath temperature or maintain a stable temperature range, the cooling medium flows within the cooling tube 211 to remove some heat, thus achieving precise control of the oil bath temperature. The heating tube 210 and the cooling tube 211 together form a two-way temperature regulation system, enabling the internal temperature of the heated oil bath 202 to both rise rapidly and maintain a stable fluctuation range near the target temperature. Through this coordinated heating and cooling regulation method, the oil bath temperature can accurately simulate the temperature conditions experienced during the asphalt pavement construction stage, thereby providing thermal conditions close to the actual construction environment for VOCs release testing.

[0029] A heat dissipation strip assembly 212 is installed above the heating oil bath 202. This assembly, typically composed of multiple sets of heat-conducting metal strips, is a structural component used for uniform heat distribution and is evenly arranged in the top area of ​​the heating oil bath 202. By expanding the heat conduction area and uniformly distributing the heat conduction path, the heat dissipation strip assembly 212 allows the heat in the oil bath medium to be transferred more evenly to the sample plate 209, thereby reducing local overheating or local undertemperature. Through the installation of the heat dissipation strip assembly 212, the sample plate 209 forms a uniformly heated surface, ensuring that asphalt pavement material samples of different sizes placed on the sample plate 209 maintain consistent thermal environment conditions during heating, thus avoiding errors in VOCs release rate testing due to uneven temperature distribution.

[0030] A temperature controller 206 is installed on the chassis 201. The temperature controller 206 is used to adjust and control the internal temperature of the heating oil bath 202 in real time. The temperature controller 206 continuously monitors the oil bath temperature through a temperature sensor 213 and controls the working status of the heating tube 210 and the cooling tube 211 according to the set target temperature. When the temperature is lower than the target temperature, the temperature controller 206 drives the heating tube 210 to start to increase the oil bath temperature; when the temperature is close to or exceeds the target temperature, the temperature controller 206 achieves stable temperature control by reducing the heating power or starting the cooling tube 211. Through the closed-loop control mechanism of the temperature controller 206, the internal temperature of the heating oil bath 202 is maintained within the preset range, thereby jointly constructing a stable controlled heating environment for the asphalt pavement material with the sample plate 209, providing reliable test conditions for testing the volatile organic compound release behavior of the asphalt pavement material.

[0031] A sealing cover 205 is installed above the sample plate 209, covering the sample plate 209 and forming a closed test space together with the chassis 201. The sealing cover 205 is typically made of high-temperature resistant transparent material or metal. Its function is to create a stable gas-sealed environment during the test, allowing the volatile organic compounds released by the asphalt pavement material sample during heating to be effectively collected and not directly diffused into the external environment. The sealing cover 205 is connected to the chassis 201 through a sealing structure, such as a sealing gasket or a threaded fastening structure, thereby ensuring good airtightness of the closed test space. By forming a closed test space, the volatile organic compounds released by the asphalt pavement material sample in a controlled environment can be stably captured, providing the basic conditions for subsequent gas sampling and analysis.

[0032] An air inlet 207 is provided on the side wall of the sealing cover 205. The air inlet 207 is used to introduce clean air or standard gas into the closed test space, thereby creating a controlled atmosphere environment. The air inlet 207 is usually connected to a gas pipeline system, and a stable airflow is continuously supplied to the closed test space through a gas delivery device. The purpose of introducing airflow is to simulate the air flow conditions in the actual construction environment, so that the volatile organic compounds released by the asphalt pavement material can enter the sampling system with the airflow, while avoiding abnormal concentration accumulation caused by prolonged gas stagnation inside the closed test space. Through the setting of the air inlet 207, a continuously flowing gas environment is formed inside the closed test space, making the test process closer to the diffusion process of volatile organic compounds under real construction conditions.

[0033] A regulating valve is installed on the air inlet 207 to control the gas flow rate entering the closed test space. The regulating valve adjusts the gas flow rate by changing the cross-sectional area of ​​the gas channel or the gas flow resistance, allowing for precise adjustment of the gas flow rate into the closed test space according to experimental requirements. When a lower airflow velocity is needed to ensure thorough gas mixing, the gas flow rate can be appropriately reduced; when a higher gas turnover rate is needed to avoid excessively high volatile organic compound (VOC) concentrations, the gas flow state inside the closed test space can be stably maintained within a preset range, thereby ensuring good repeatability of VOC concentration detection results under different experimental conditions.

[0034] A sampling port 208 is provided at the top of the sealing cover 205. The sampling port 208 is directly connected to the closed test space and is used to extract and sample the gas containing volatile organic compounds (VOCs) from the closed test space for analysis. The sampling port 208 is usually connected to a sampling pipeline or gas sampling device. The gas sampling device continuously extracts gas from the closed test space, allowing the VOC-containing gas to enter the sampling container or analytical instrument. Gas is continuously input through the air inlet 207 and extracted through the sampling port 208, forming a stable gas flow channel inside the closed test space. This allows the VOCs released by the asphalt pavement material under controlled heating to stably enter the sampling system. This gas flow channel ensures continuous renewal of the gas environment during the test, enabling the gas sample obtained from the sampling port 208 to accurately reflect the VOC release state of the asphalt pavement material under the current heating conditions.

[0035] In one possible implementation, based on a pre-set testing device, VOC emission concentration detection is conducted on a multi-scale sample set under simulated typical road conditions. Specifically, this includes: placing asphalt pavement materials of different scales sequentially on the sample plate 209, ensuring contact between the asphalt pavement materials and the heated surface of the sample plate 209; setting the target temperature of the oil bath medium inside the heating oil bath 202 via a temperature controller 206, and driving the heating tube 210 to increase the temperature of the oil bath medium via the temperature controller 206; achieving uniform heat transfer between the heating oil bath 202 and the sample plate 209 via a heat dissipation strip assembly 212, thereby creating a stable and uniform heating environment for the sample plate 209; introducing gas into the closed test space formed by the sealing cover 205 and the chassis 201 through the air inlet 207, and controlling the gas flow through the air inlet 207. The regulating valve on the air inlet 207 adjusts the gas flow rate to create a stable displacement atmosphere inside the closed test space. Simultaneously, the sampling port 208, located on top of the sealing cover 205, remains in a gas collection state, forming a gas flow channel for exporting VOCs released from the asphalt pavement material. Under the condition of a stable displacement atmosphere within the closed test space, the asphalt pavement material continuously releases VOCs under the heating effect of the sample plate 209. With continuous gas supply from the air inlet 207 and the regulating valve controlling the gas flow rate, the gas inside the closed test space maintains continuous flow and stable displacement, thus creating a dynamic gas environment for the released VOCs within the closed test space. Gas samples are extracted from the closed test space through the sampling port 208 to obtain VOCs gas samples released by the asphalt pavement material under the current heating conditions.

[0036] Specifically, asphalt pavement materials of different scales are placed sequentially on sample plate 209 at the start of the test. Sample plate 209, as the heating component directly bearing the asphalt pavement materials, has its upper surface as the heating surface in contact with the asphalt pavement material sample. The so-called multi-scale sample set refers to a set of samples composed of asphalt, asphalt binder, asphalt mortar, and asphalt concrete, reflecting different structural scales of the asphalt pavement structure from the base binder to the macro-mixture structure. When the sample is placed on sample plate 209, the flat bearing surface of sample plate 209 ensures full contact between the asphalt pavement material sample and the heating surface, thereby forming a stable heat transfer path. This allows the heat from the heating oil bath 202 to be evenly transferred to the interior of the asphalt pavement material sample through sample plate 209. By placing asphalt pavement materials of different scales sequentially, each sample is heated and tested under the same heating conditions, ensuring the comparability of VOC emission concentration test results between asphalt pavement materials of different scales.

[0037] The target temperature of the oil bath medium inside the heating oil bath 202 is set by the temperature controller 206. The oil bath medium is heat-conducting oil filled inside the heating oil bath 202, which acts as a heat transfer medium to ensure uniform heat distribution within the heating oil bath 202. The temperature controller 206 is a temperature regulation and control component that, in conjunction with the temperature sensor 213, monitors the temperature of the oil bath medium in real time and controls the operating state of the heating tube 210 according to the set target temperature. When the temperature controller 206 receives a temperature setting command, it drives the heating tube 210 to start, causing the heating tube 210 to continuously release heat to the oil bath medium through electric heating, thereby gradually increasing the temperature of the oil bath medium until it reaches the set temperature range. In this way, the high-temperature conditions experienced during the asphalt pavement construction stage can be simulated in the test environment, thus providing a realistic temperature environment for the release behavior of volatile organic compounds in asphalt pavement materials.

[0038] The heat dissipation strip assembly 212 ensures uniform heat transfer between the heating oil bath 202 and the sample plate 209. The heat dissipation strip assembly 212 is a heat-conducting structural component located at the top of the heating oil bath 202, consisting of multiple sets of heat-conducting metal strips evenly arranged in space. The function of the heat dissipation strip assembly 212 is to expand the heat conduction path and distribute heat evenly, allowing heat from the oil bath medium to be transferred to all areas of the sample plate 209, thus avoiding excessively high or low temperatures in localized areas. Through the arrangement of the heat dissipation strip assembly 212, the sample plate 209 as a whole forms a stable and uniform heating environment, ensuring consistent heat input conditions for asphalt pavement material samples of different sizes during heating, thereby reducing VOCs release differences caused by uneven temperature distribution.

[0039] Gas is introduced into the closed test space formed by the sealing cover 205 and the chassis 201 through the air inlet 207, and the gas flow rate is regulated by a regulating valve located on the air inlet 207. The closed test space is a gas space structure formed by the sealing cover 205 covering the sample plate 209 and sealing it with the chassis 201. Its interior is used to contain volatile organic compounds released by the asphalt pavement material sample during heating. The air inlet 207 is a channel structure connecting the gas pipeline, through which clean air is continuously supplied to the closed test space, thereby creating a controlled atmosphere environment. The regulating valve is a gas flow control component located on the air inlet 207. By changing the opening of the gas channel, it regulates the gas flow rate entering the closed test space, thus creating a stable displacement atmosphere inside the closed test space. The displacement atmosphere refers to the continuous replenishment of gas inside the closed test space by continuously supplying and simultaneously venting gas, thereby preventing the long-term accumulation of volatile organic compounds within the space. At the same time, the sampling port 208 at the top of the sealing cap 205 remains connected to the sampling system, allowing the released volatile organic compounds to be discharged along the gas flow direction, thereby forming a stable gas flow channel.

[0040] Under stable displacement atmosphere conditions within the closed test space, the asphalt pavement material gradually heats up under the heating effect of sample slab 209, and the volatile organic compounds (VOCs) contained within it begin to migrate and release into the closed test space. VOCs refer to organic chemical substances that can volatilize from the asphalt material and enter the gas phase under heating conditions. With continuous air supply from multiple air inlets 207 and gas flow control via multiple regulating valves, a continuous airflow is formed within the closed test space, ensuring constant gas renewal and maintaining a stable flow state. Through continuous air supply and flow regulation, the released VOCs do not accumulate statically within the closed test space but instead form a dynamic gas environment with the airflow, thus more closely resembling the diffusion behavior of VOCs in the air during asphalt pavement construction.

[0041] Volatile organic compound (VOC) gas samples are obtained by extracting gas from the enclosed test space through sampling port 208. Sampling port 208 is a gas outlet structure located on top of the sealing cover 205 and communicating with the enclosed test space; it is typically connected to a sampling pipeline and a gas sampling device. The gas sampling device continuously pumps gas from the enclosed test space, drawing it out along a gas flow channel and into the sampling system. Because the gas inside the enclosed test space is in a state of continuous flow and stable displacement, the gas sample obtained through sampling port 208 reflects the immediate VOC emission level of the asphalt pavement material under current heating conditions, rather than the concentration level accumulated under conditions in a confined space. The VOC gas samples obtained through this sampling method can be further used for concentration analysis, thus providing basic data for subsequent emission rate calculations and total emission calculations.

[0042] S120, based on a multi-level concentration dataset, uniformly characterizes the VOCs emission behavior of asphalt pavement materials at different scales, thereby obtaining the VOCs emission characteristic representation results corresponding to asphalt pavement materials at each scale.

[0043] In one possible implementation, before uniformly characterizing the VOCs emission behavior of asphalt pavement materials at different scales based on a multi-level concentration data set, thereby obtaining the VOCs emission characteristic characterization results corresponding to asphalt pavement materials at each scale, the method further includes: constructing a multi-scale sample set using a uniform asphalt quality as the test benchmark, and constructing asphalt concrete into compacted asphalt concrete samples and loose asphalt concrete samples under the uniform asphalt quality benchmark. The compacted asphalt concrete samples are prepared with a regular geometric structure matching the sample plate 209 of the heated oil bath 202 to ensure uniform heating, while the loose asphalt concrete samples are uniformly spread on the surface of the bearing carrier under uniform quality conditions; under the uniform asphalt quality benchmark... The amount of asphalt in asphalt mortar is determined based on the asphalt-aggregate ratio of asphalt concrete. Compacted and loose asphalt mortar samples are constructed, ensuring that the compacted asphalt mortar samples maintain the same compacted structure as the compacted asphalt concrete samples. Simultaneously, the loose asphalt mortar samples are spread on the surface of the load-bearing carrier under uniform quality conditions. Under a uniform asphalt quality standard, the ratio of asphalt to mineral powder in the asphalt mastic is determined based on the asphalt-aggregate ratio and the powder-binder ratio. The asphalt mastic is then prepared as a thin film structure to form asphalt mastic samples. The amount of asphalt used in the samples is determined under a uniform asphalt quality standard, and the asphalt samples are prepared as thin film structures. This results in a multi-scale sample set encompassing asphalt, asphalt mastic, asphalt mortar, and asphalt concrete under a uniform asphalt quality standard.

[0044] Specifically, a unified asphalt quality benchmark is used to ensure the comparability of asphalt pavement materials at different scales during testing. This benchmark refers to using the same mass of asphalt as a common reference for constructing samples at different scales, ensuring a consistent asphalt content base across all scales. When constructing a multi-scale sample set, the mass of asphalt contained in the asphalt concrete sample is first determined based on the unified asphalt quality benchmark. Then, a corresponding proportion of aggregate is added based on this mass to form the asphalt concrete sample. During preparation, the asphalt concrete sample is divided into compacted and loose asphalt concrete samples. The compacted asphalt concrete sample undergoes compaction of the asphalt mixture using compaction equipment, forming a stable skeletal structure between the aggregate particles. The compacted sample is then processed into a regular geometric structure that matches the dimensions of the sample plate 209, ensuring that the bottom surface of the sample completely conforms to the heated surface of the sample plate 209, thus guaranteeing uniform heating during the heating process. Loose asphalt concrete specimens are prepared by maintaining the uncompacted aggregate state and uniformly spreading the specimens on the surface of a supporting carrier under uniform mass conditions. The supporting carrier is a planar structure designed to support the loose specimens, ensuring that the loose specimens form a uniformly distributed material layer and thus guaranteeing consistent heating conditions in different areas during the heating process. By using both compacted and loose asphalt concrete specimens, a multi-scale specimen ensemble can simultaneously reflect the volatile organic compound release behavior of asphalt concrete under different structural states.

[0045] Under a unified asphalt quality standard, the amount of asphalt in the asphalt mortar sample is determined based on the asphalt-aggregate ratio used in the asphalt concrete sample. The asphalt-aggregate ratio refers to the proportional relationship between the mass of asphalt and the mass of aggregate, which describes the proportion between binder and aggregate in asphalt mixtures. Once the asphalt-aggregate ratio in the asphalt concrete sample is determined, the required mass of aggregate for the asphalt mortar sample under the same asphalt quality conditions can be calculated by reverse calculation. The asphalt mortar sample consists of asphalt and fine aggregate, excluding coarse aggregate. Based on this ratio, compacted and loose asphalt mortar samples are constructed. The compacted asphalt mortar sample forms a stable granular structure through compaction, ensuring that its structural morphology remains consistent with that of the compacted asphalt concrete sample, thus guaranteeing that the material structure remains consistent even under changes in structural dimensions. Loose asphalt mortar samples are spread on the surface of the load-bearing carrier under uniform mass conditions, so that the asphalt mortar material forms a uniformly distributed material layer in an uncompacted state. In this way, a consistent sample construction logic can be maintained between different material scales, so that asphalt mortar samples can serve as an intermediate material scale for the transition from the asphalt concrete structure to the microscale.

[0046] Under a unified asphalt quality standard, the ratio of asphalt to mineral powder in asphalt mastic samples is determined based on the asphalt-aggregate ratio and the mineral powder-binder ratio. The mineral powder-binder ratio refers to the ratio between the mass of mineral powder and the mass of asphalt, describing the proportion of filler and binder in the asphalt mastic. Based on the determined asphalt-aggregate ratio, the mass of mineral powder in the asphalt mastic is further calculated using the mineral powder-binder ratio, ensuring that the material composition of the asphalt mastic sample maintains logical consistency with that of asphalt mortar and asphalt concrete samples. Asphalt mastic samples are typically prepared using a thin-film structure, where the prepared asphalt mastic material is evenly spread to form a continuous material layer, resulting in a thin, uniformly distributed film structure. A thin-film structure refers to a material form with a small thickness and a continuous planar structure. This structure allows for uniform heating of the asphalt mastic during heating and enables the uniform release of volatile organic compounds from the material surface, facilitating subsequent emission concentration detection.

[0047] The amount of asphalt sample used was further determined under a unified asphalt quality standard. The asphalt sample is a basic material scale composed of pure asphalt material, and its asphalt quality is directly consistent with the unified asphalt quality standard, thus ensuring that all samples in the multi-scale sample set are based on the same asphalt quality. The asphalt sample is also prepared as a thin film structure. By uniformly spreading the asphalt material on a planar substrate to form a continuous material layer, the asphalt sample has a stable thickness and uniform distribution, thereby creating uniform heating conditions during the heating process. Preparing the asphalt sample as a thin film structure allows volatile organic compounds (VOCs) inside the asphalt to be uniformly released from the material surface under heating conditions, thus providing a stable material state for subsequent VOC emission concentration detection.

[0048] Through the aforementioned sample construction process, a multi-scale sample ensemble was formed under a unified asphalt quality benchmark, comprising asphalt samples, asphalt mastic samples, asphalt mortar samples, and asphalt concrete samples. This multi-scale sample ensemble represents the material system of the asphalt pavement structure at different structural scales. The asphalt samples represent the binder scale, the asphalt mastic samples represent the filler-binder coupling scale, the asphalt mortar samples represent the fine aggregate structural scale, and the asphalt concrete samples represent the macroscopic mixture structural scale. By constructing this multi-scale sample ensemble under a unified asphalt quality benchmark, consistency in material composition and quality benchmarks is ensured across different material scales, thereby guaranteeing comparability and consistency among materials at each scale during subsequent volatile organic compound (VOC) emission concentration detection and emission behavior analysis.

[0049] In one possible implementation, the VOCs emission behavior of asphalt pavement materials at different scales is uniformly characterized based on a multi-level concentration data set. Specifically, this includes: heating asphalt pavement materials at different scales under simulated temperature conditions to obtain VOCs emission concentration data for each scale, thus forming an emission concentration data set. The simulated temperature conditions are constructed based on the construction characteristics of the asphalt pavement project within the experimental environment. Based on the emission concentration data set, the emission rate data of each VOCs substance under unit time and unit asphalt mass conditions are calculated to form an emission rate data set. Based on the emission rate data set, the emission amount of each VOCs substance within the monitoring time range is calculated to form an emission amount data set, and the emission amount is determined according to the chemical structure of the VOCs substances. VOCs are classified into components based on their characteristics and chemical bond types, forming component sets of VOCs belonging to the same component. The emission data of each VOC in the component set are accumulated to obtain component emission data. At the same time, the component emission data obtained under different temperature conditions are summarized and accumulated to obtain the total VOC emission data during the asphalt pavement construction stage. Based on the emission concentration data set, emission rate data set, and total VOC emission data, and combined with four scales (asphalt, asphalt mastic, asphalt mortar, and asphalt mixture) and three levels (total concentration, component concentration, and monomer concentration), the VOC emission behavior of asphalt pavement materials is uniformly characterized to form VOC emission characteristic characterization results of emission concentration, emission rate, and total emission.

[0050] Furthermore, based on the emission concentration data set, the emission rate data of each VOCs substance under unit time and unit asphalt mass conditions are calculated to form an emission rate data set. Specifically, this includes: averaging the emission concentration data of the same VOCs substance obtained from each sampling to obtain the average emission concentration data within the monitoring time range; multiplying the average emission concentration data with the VOCs emission volume per unit monitoring time under temperature environment simulation conditions to obtain the emission amount data of VOCs substances under unit time conditions; and calculating the ratio of the emission amount data with the mass of asphalt material involved in the detection under temperature environment simulation conditions to obtain the emission rate data of VOCs substances under unit time and unit asphalt mass conditions, thereby forming an emission rate data set.

[0051] Specifically, the temperature environment simulation conditions are used to reproduce the temperature evolution characteristics of asphalt pavement construction projects during the construction phase in a test environment. The construction method determines the set of temperature intervals and the duration of each temperature interval based on construction characteristics, ensuring that subsequent heating treatment is not a single constant-temperature test but rather consistent with the temperature changes during the construction process. The heating treatment is provided by a pre-set testing device, which provides a controlled heating environment, allowing asphalt pavement materials of different scales to be sequentially subjected to stable heating under the same temperature environment simulation conditions. Multiple gas sampling and concentration detection are performed within each temperature interval duration to obtain VOCs emission concentration data. The emission concentration dataset contains the concentration detection results of asphalt pavement materials of different scales at each temperature interval. These materials include asphalt, asphalt mastic, asphalt mortar, and asphalt mixtures. The VOCs emission concentration data includes both the summary results of the total concentration level and the decomposition results of the component concentration level and the concentration level of individual substances, thus providing a consistent data base for the subsequent calculation of emission rates and total emissions.

[0052] Emission rate data is used to characterize the release intensity of the i-th VOCs per unit time and per unit mass of asphalt at temperature T. Its calculation involves extracting multiple sampling concentration data of the same substance at temperature T from the emission concentration dataset and averaging them to reduce the impact of random sampling disturbances on the results. After obtaining the average emission concentration, the average emission concentration is multiplied by the emission volume per unit monitoring time at temperature T to obtain the emission rate per unit time. This is then normalized using the mass of asphalt material used for detection at temperature T to obtain the emission rate per unit mass. The expression for emission rate is:

[0053]

[0054] in, This represents the emission rate of the i-th substance at temperature T, and its value is a non-negative real number. The value represents the average emission concentration of the i-th substance obtained from the j-th sampling at temperature T, and is a non-negative real number; n represents the number of samplings at temperature T, and is a positive integer. It represents the emission volume per unit monitoring time at temperature T, and is a positive real number. It can be obtained by converting the gas flow rate and monitoring time under a stable displacement atmosphere in a closed test space. This represents the mass of asphalt material used in the test at temperature T. It is a positive real number, typically determined by a standardized asphalt quality standard or sample preparation records. The principle behind this expression is to map the gas phase concentration to the emission volume per unit time through emission volume, and to normalize the asphalt material mass to achieve comparability between materials of different scales.

[0055] Emission data characterizes the cumulative emission of the i-th VOC substance over a given temperature interval within the monitoring timeframe. Calculations are based on the emission rate dataset, with time-weighted accumulation of emission rates according to the temperature interval set, explicitly incorporating the impact of temperature changes on release intensity over time. Component classification groups the emissions at the individual substance level into several component sets based on chemical structure characteristics and bond types. This establishes a stable comparative dimension at the component level and enhances the interpretability of cross-scale analysis. Chemical structure characteristics characterize carbon chain and ring structures, while bond types characterize saturated and unsaturated bonds and functional group bonds, allowing each VOC substance to be categorized as alkanes, alkenes, aldehydes, ketones, benzene compounds, esters, halogenated hydrocarbons, and other components. The expressions for the emission amounts of each substance are as follows:

[0056]

[0057] in, This represents the emission amount of the i-th substance within the monitoring time range, and its value is a non-negative real number; This represents the emission rate of the i-th substance at temperature T, and its value is a non-negative real number. This represents the duration of the asphalt material at temperature T, and is a positive real number. It is obtained by statistically analyzing the set of temperature interval durations in the temperature environment simulation conditions. m and n represent the start and end indices of the set of temperature intervals, which are used to cover all temperature intervals within the monitoring time range. This represents the mass of asphalt material at the activity level, and is a positive real number. It can be obtained from the material usage records corresponding to the construction activity level. The principle behind this expression is to accumulate the emission rate over a temperature range over time, forming a cumulative release per unit mass, and then mapping it to the mass of asphalt material at the activity level to obtain the emission amount within the monitoring time range.

[0058] Component emission data is used to summarize the emissions of individual substances at the component level, ensuring traceability between component-level and individual substance-level results and supporting subsequent comparisons of component concentration levels. Accumulation processing, using the component set as a boundary, sums the emission data of each VOCs substance belonging to the same component set to obtain the component emission data, thus enabling the component emission data to reflect the overall contribution of that component within the monitoring time range. The summation and accumulation of component emission data under different temperature conditions is used to merge the segmented results of temperature range sets into a comprehensive result for the asphalt pavement construction stage, ensuring that the total VOCs emission data during the asphalt pavement construction stage covers the entire process from the initial temperature range to the final temperature range. The total VOCs emission data can be further obtained by summing the emission data of each individual substance, expressed as:

[0059]

[0060] Where M represents the total VOCs emissions within the monitoring time period, and its value is a non-negative real number; The value represents the emission amount of the i-th substance, and is a non-negative real number; k represents the total number of VOCs substances, and is a positive integer, determined based on the list of target substances detected and identified. The principle of this expression is to use individual substances as the smallest unit of measurement, and to sum the emissions of all individual substances to obtain the total emission level index, so that the total emission level index and the individual substance level index are consistent in the calculation chain.

[0061] The VOCs emission characterization results are used to uniformly express the emission behavior of asphalt pavement materials within a multi-scale and multi-level framework. Four scales constrain the material structure dimension, making asphalt, asphalt mastic, asphalt mortar, and asphalt mixtures comparable within the same evaluation framework. Three levels constrain the concentration analysis dimension, making total concentration, component concentration, and monomer concentration traceable within the same data chain. The emission concentration dataset provides an instantaneous emission status characterization under simulated temperature conditions; the emission rate dataset provides a characterization of release intensity per unit time and per unit mass of asphalt; and the total VOCs emission data provides an overall emission characterization accumulated over time within the monitoring period and temperature range. These three types of data form a closed-loop mapping relationship under the same simulated temperature conditions and the same sample reference conditions. This allows the VOCs emission characterization results to simultaneously output a three-dimensional evaluation of emission concentration, emission rate, and total emission, maintaining consistent interpretability and comparability across the three levels of total concentration, component concentration, and monomer concentration.

[0062] S130, based on the VOCs emission characteristic characterization results, conducts a correlation analysis on the VOCs emission patterns among asphalt pavement materials at different scales, thereby completing a cross-scale comprehensive analysis and evaluation of the VOCs emission characteristics of asphalt-based materials.

[0063] In one possible implementation, based on the VOCs emission characteristic characterization results, a correlation analysis is performed on the VOCs emission patterns among asphalt pavement materials of different scales. Specifically, this includes: constructing a cross-scale analysis dataset based on the VOCs emission characteristic characterization results; and uniformly organizing the emission concentration dataset, emission rate dataset, and total VOCs emission data through material scale identifiers and concentration hierarchy identifiers, thereby forming a cross-scale analysis data structure for asphalt pavement materials of different scales; performing temperature interval alignment processing on the emission concentration dataset based on the temperature interval set and the temperature interval duration set, so that the VOCs emission concentration data of asphalt pavement materials of different scales under the same temperature interval conditions form a comparable data sequence; and based on the temperature interval aligned emission concentration dataset and emission rate dataset, performing a scale correlation analysis on the emission rates of asphalt, asphalt mastic, asphalt mortar, and asphalt mixture—four scales of asphalt pavement materials—under the same temperature interval conditions, to obtain the cross-scale analysis data structure for asphalt pavement materials of different scales. The study investigates the correlation between VOCs release rates among materials; performs cross-scale cumulative statistical analysis on emission data sets based on emission rate correlations to obtain the VOCs emission contribution relationship of asphalt pavement materials at different scales within the monitoring time range; performs component hierarchical correlation analysis on emission data of asphalt pavement materials at different scales within each component set based on component sets to obtain the VOCs emission characteristic correlation of asphalt pavement materials at different scales in terms of chemical component distribution; conducts a total VOCs emission level comparison analysis of asphalt pavement materials at different scales during the asphalt pavement construction stage based on total VOCs emission data; and constructs a cross-scale emission characteristic evaluation framework based on emission concentration data sets, emission rate data sets, and total VOCs emission data at four material scales (asphalt, asphalt mastic, asphalt mortar, and asphalt mixture) and three concentration levels (total concentration, component concentration, and monomer concentration) to complete the cross-scale comprehensive analysis and evaluation of VOCs emission characteristics of asphalt-based materials.

[0064] Specifically, the construction of the cross-scale analysis dataset extracts three core data objects from the VOCs emission characteristic characterization results and structures them accordingly. The emission concentration dataset carries total concentration data, component concentration data, and individual substance concentration data obtained under simulated temperature conditions. The emission rate dataset carries emission rate data for each individual substance derived from the emission concentration dataset. The total VOCs emission data carries the cumulative emission amounts of each individual substance over time according to temperature intervals and its summary results. Material scale identifiers bind data objects to four material scales: asphalt, asphalt mastic, asphalt mortar, and asphalt mixture. Concentration level identifiers bind data objects to total concentration, component concentration, and individual substance concentration levels, thus forming a unified data key structure within the cross-scale analysis dataset. This allows any data entry to be located by the material scale identifier, concentration level identifier, temperature interval identifier, and sampling time identifier. The unified organization of material scale identifiers and concentration level identifiers enables the three types of data objects to be traced and mapped within the same index space. For example, the concentration data of individual substances under the same material scale identifier can be traced back to the component concentration data and total concentration data under the same material scale identifier along the index relationship, and further linked with the emission rate data and VOCs emission total data under the same material scale identifier, thereby ensuring that the data sources used for cross-scale comparisons are consistent and the caliber is consistent.

[0065] Temperature range alignment relies on establishing a unified temperature axis using a set of temperature ranges and a set of temperature range durations. This allows emission concentration data from different material scales under the same temperature range to form a comparable data sequence. The set of temperature ranges is determined by temperature environment simulation conditions, while the set of temperature range durations is obtained from temperature evolution statistics during the asphalt pavement construction phase and is used to define the effective sampling window within each temperature range. During alignment, the emission concentration data set is grouped according to temperature range identifiers, and representative values ​​are extracted from multiple samplings within each temperature range. This ensures that different material scales correspond to one or more alignment points within the same temperature range. Representative value extraction can use the interval mean to reduce sampling noise and maintain consistency in representing steady-state release levels. The expression for the interval mean is:

[0066]

[0067] in, This represents the interval average emission concentration of the i-th monomeric substance within a temperature range of temperature T, and its value is a non-negative real number. The expression represents the average emission concentration of the i-th monomeric substance obtained from the j-th sampling within a temperature range of temperature T, and is a non-negative real number; n represents the number of samplings within this temperature range, and is a positive integer. The principle behind this expression is to statistically aggregate the emission status of the same temperature range through multiple samplings within the range, thereby forming aligned data points with the same caliber for different material scales within the same temperature range, and thus constructing a comparable data sequence.

[0068] Scale correlation analysis is based on temperature-range aligned emission concentration and emission rate datasets, establishing scale correlations around the differences in release intensity at different material scales within the same temperature range. In practice, emission rate data under the same temperature range are grouped into four scale sequences based on material scale. The correlation strength between these scale sequences is calculated at the same monomer or component dimension to obtain the correlation between VOC release rates at different material scales. To simultaneously characterize linear consistency and monotonic consistency, correlation coefficients and rank correlation coefficients can be used for joint determination. The expression for the correlation coefficient is:

[0069]

[0070] in, This represents the correlation coefficient of emission rates between material scale a and material scale b within a temperature range of T, with a value ranging from negative one to positive one. This represents the emission rate of material scale a in the p-th aligned dimension within a temperature range of temperature T. The aligned dimension can be either a monomer index or a component index. This represents the emission rate of material scale b within the same temperature range and along the same aligned dimension. and Let represent the average emission rates of material scale a and material scale b within the same temperature range, respectively; P represents the number of aligned dimensions involved in the correlation calculation, and its value is a positive integer. The principle behind this expression is to compare the degree of synchronization between the emission rates of each aligned dimension of the two material scales and their deviations from the mean within the same temperature range, thereby quantifying the synergistic relationship between the release intensity of materials at different scales and the changes in material dimensions.

[0071] Cross-scale cumulative statistical analysis uses emission rate correlations as constraints and applies them to the emission dataset, extending the correlation from the instantaneous intensity level to the cumulative contribution level over the monitoring time period. In implementation, the emission dataset is first decomposed according to material scale and temperature range identifiers to obtain the emissions of individual substances and components at each material scale within each temperature range. Then, time-based cumulative summation is performed on different temperature ranges within the same material scale to obtain the cumulative emissions over the monitoring time period. Finally, the contribution ratio is calculated between different material scales to establish the VOCs emission contribution relationship. The expression for the contribution ratio is:

[0072]

[0073] in, This represents the contribution ratio of material scale a to the emission of a single substance in dimension i, with a value ranging from zero to one. This represents the emission amount of the i-th monomeric substance at material scale a within the monitoring time range; This refers to a set of material dimensions, typically including asphalt, asphalt mastic, asphalt mortar, and asphalt mixtures; This represents the sum of emissions of the same monomeric substance across all material scales. The principle behind this expression is to normalize the cumulative emissions of the same monomeric substance across different material scales, thereby transforming cross-scale differences into a directly comparable contribution structure. This structure, together with the emission rate correlation, is used to identify the amplification or suppression effect of scale changes on cumulative emissions.

[0074] Component-level correlation analysis uses component sets as the alignment dimension, transforming differences in chemical component distribution across different material scales into quantifiable emission characteristic correlations. During implementation, monomeric substances are grouped into component sets such as alkanes, alkenes, aldehydes, ketones, benzene compounds, esters, halogenated hydrocarbons, and other components based on their chemical structure and bond types. A component emission vector is generated for each material scale within the monitoring timeframe. Subsequently, distribution similarity calculations are performed on the component emission vectors at different material scales to obtain the correlation strength at the chemical component distribution level. To ensure that the similarity is insensitive to differences in total scale, the component emission vectors are first normalized to component proportion vectors before calculating the distribution distance. The expression for component proportion is:

[0075]

[0076] in, This represents the emission proportion of material scale a in component g, with a value ranging from zero to one. This represents the emission amount of component g at material scale a within the monitoring time range; This represents the set of components. The principle behind this expression is to normalize the sum of component emissions at the material scale using the component emission rate, thereby obtaining the component composition characteristics. Based on this, correlation analysis is then performed on the component composition characteristics at different material scales to identify the influence of mineral structure, filler structure, and binder structure on the chemical component release preference.

[0077] The total emission level comparative analysis uses total VOC emissions data as a unified evaluation caliber to assess the comparability of overall emission levels at different material scales during the asphalt pavement construction phase. In practice, the total VOC emissions at each material scale are obtained by summarizing the emissions of individual substances across different material types. A horizontal comparison is then conducted under the same activity level or the same unified asphalt quality caliber to identify the suppressive or enhancing trends of scale changes on overall emission levels. The expression for total VOC emissions is:

[0078]

[0079] in, This represents the total VOC emissions at material scale a within the monitoring time range, and its value is a non-negative real number. Let represent the emission of the i-th individual substance at material scale 'a'; k represents the total number of substance types, taking a positive integer value. The principle behind this expression is to sum the cumulative emissions of all individual substances to form a total emission level index. This total emission level index can reflect the overall emission level at different material scales under the same activity level caliber, and provide a benchmark quantity for the total emission dimension of subsequent evaluation frameworks.

[0080] The cross-scale emission characteristic evaluation framework integrates emission concentration data sets, emission rate data sets, and total VOC emission data at both the material scale and concentration level dimensions. This ensures that the evaluation output covers all three categories of indicators—emission concentration, emission rate, and total emission—within the same framework, maintaining a consistent and traceable relationship across the total concentration level, component concentration level, and individual substance concentration level. In implementation, four material scale evaluation units are first identified by the material scale, and three concentration level evaluation perspectives are identified by the concentration level. This allows each evaluation unit to output emission concentration characteristics, emission rate characteristics, and total emission characteristics at the corresponding level. Subsequently, comparable data sequences generated by temperature range alignment, release rate correlations generated by scale correlation analysis, emission contribution relationships generated by cross-scale cumulative statistical analysis, chemical component distribution correlations generated by component level correlation analysis, and overall emission level differences generated by total emission level comparative analysis are all incorporated into the evaluation results, thus forming a comprehensive cross-scale analysis and assessment conclusion. The framework's operational logic ensures that all correlation analyses are constrained by the same temperature environment simulation conditions, the same material scale labeling system, and the same concentration level labeling system, so that the conclusions of cross-scale comprehensive analysis and evaluation can be consistent in terms of data sources, calculation methods, and interpretation paths.

[0081] This embodiment also discloses a multi-scale, multi-level evaluation device for VOCs emission characteristics of asphalt pavement materials, referring to... Figure 3The device includes an acquisition module 301, a processing module 302, and an output module 303. It is used to execute any of the above-described methods for cross-scale, multi-level evaluation of VOCs emission characteristics of asphalt pavement materials, wherein: The acquisition module 301 is used to detect VOCs emission concentration on a multi-scale sample set under simulated typical road conditions based on a preset evaluation device, and to analyze the VOCs emission concentration data at three levels: total concentration, component concentration and individual substance concentration, so as to form a multi-level concentration data set corresponding to asphalt pavement materials at different scales. Processing module 302 is used to uniformly characterize the VOCs emission behavior of asphalt pavement materials at different scales based on multi-level concentration data sets, thereby obtaining VOCs emission characteristic characterization results corresponding to asphalt pavement materials at each scale. Output module 303 is used to perform correlation analysis on the VOCs emission patterns among asphalt pavement materials at different scales based on the VOCs emission characteristic characterization results, thereby completing the cross-scale comprehensive analysis and evaluation of the VOCs emission characteristics of asphalt-based materials.

[0082] It should be noted that the above embodiments of the apparatus are only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the apparatus and method embodiments provided in the above embodiments belong to the same concept, and the specific implementation process can be found in the method embodiments, which will not be repeated here.

[0083] This embodiment also discloses an electronic device, as shown in the reference. Figure 4 The electronic device may include: at least one processor 401, at least one communication bus 402, user interface 403, network interface 404, and at least one memory 405.

[0084] The communication bus 402 is used to enable communication between these components.

[0085] The user interface 403 may include a display screen and a camera. Optionally, the user interface 403 may also include a standard wired interface and a wireless interface.

[0086] The network interface 404 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface).

[0087] The processor 401 may include one or more processing cores. The processor 401 connects to various parts of the server using various interfaces and lines, and performs various server functions and processes data by running or executing instructions, programs, code sets, or instruction sets stored in memory 405, and by calling data stored in memory 405. Optionally, the processor 401 may be implemented using at least one hardware form of Digital Signal Processing (DSP), Field-Programmable Gate Array (FPGA), or Programmable Logic Array (PLA). The processor 401 may integrate one or a combination of several of the following: Central Processing Unit (CPU), Graphics Processing Unit (GPU), and modem. The CPU primarily handles the operating system, user interface, and applications; the GPU is responsible for rendering and drawing the content required for display; and the modem handles wireless communication. It is understood that the modem may also be implemented as a separate chip without being integrated into the processor 401.

[0088] The memory 405 may include random access memory (RAM) or read-only memory. Optionally, the memory may include a non-transitory computer-readable storage medium. The memory 405 may be used to store instructions, programs, code, code sets, or instruction sets. The memory 405 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as touch function, sound playback function, image playback function, etc.), instructions for implementing the above-described method embodiments, etc.; the data storage area may store data involved in the above-described method embodiments, etc. Optionally, the memory 405 may also be at least one storage device located remotely from the aforementioned processor 401. As a computer storage medium, the memory 405 may include an operating system, a network communication module, a user interface 403 module, and an application program for a cross-scale multi-level evaluation method of VOCs emission characteristics of asphalt pavement materials.

[0089] exist Figure 4In the electronic device shown, the user interface 403 is mainly used to provide an input interface for the user and to obtain the user input data; while the processor 401 can be used to call the application program stored in the memory 405 for a cross-scale multi-level evaluation method of VOCs emission characteristics of asphalt pavement materials. When executed by one or more processors 401, the electronic device performs one or more methods as described in the above embodiments.

[0090] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, as some steps can be performed in other orders or simultaneously according to the present invention. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0091] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0092] In the several embodiments provided by this invention, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some service interface; the indirect coupling or communication connection between apparatuses or units may be electrical or other forms.

[0093] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0094] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0095] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage device (CMD). Based on this understanding, the technical solution of this invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory 405 and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned memory 405 includes various media capable of storing program code, such as a USB flash drive, external hard drive, magnetic disk, or optical disk.

[0096] The present invention also discloses a non-transitory computer-readable storage medium storing instructions. When executed by one or more processors 401, these instructions cause an electronic device to perform one or more methods as described in the above embodiments.

[0097] The above are merely exemplary embodiments of this disclosure and should not be construed as limiting the scope of this disclosure. Any equivalent changes and modifications made in accordance with the teachings of this disclosure shall still fall within the scope of this disclosure. Those skilled in the art will readily conceive of other embodiments of this disclosure upon considering the specification and the disclosure of practical truths. This invention is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not described in this disclosure. The specification and embodiments are to be considered exemplary only, and the scope and spirit of this disclosure are defined by the claims.

Claims

1. A multi-scale, multi-level evaluation method for VOCs emission characteristics of asphalt pavement materials, characterized in that, The method includes: Based on the pre-set evaluation device, VOCs emission concentration was detected on a multi-scale sample set under simulated typical road conditions. The VOCs emission concentration data were analyzed at three levels: total concentration, component concentration, and individual substance concentration, in order to form a multi-level concentration data set corresponding to asphalt pavement materials at different scales. Based on the multi-level concentration data set, the VOCs emission behavior of asphalt pavement materials at different scales is uniformly characterized, thereby obtaining the VOCs emission characteristic characterization results corresponding to the asphalt pavement materials at each scale. Based on the VOCs emission characteristics characterization results, a correlation analysis was conducted on the VOCs emission patterns among asphalt pavement materials at different scales, thereby completing a cross-scale comprehensive analysis and evaluation of the VOCs emission characteristics of asphalt-based materials.

2. The method for multi-scale, multi-level evaluation of VOCs emission characteristics of asphalt pavement materials according to claim 1, characterized in that, The preset testing device includes a chassis, a heated oil bath disposed inside the chassis, and an oil inlet and an oil outlet connected to the heated oil bath, wherein: The heated oil bath is equipped with a sample plate for supporting the asphalt pavement material. Heating and cooling pipes for adjusting the oil bath temperature are installed inside the heated oil bath. A heat dissipation strip assembly is provided above the heating oil bath to ensure that heat is evenly transferred to the sample plate. A temperature controller is installed on the chassis to adjust the internal temperature of the heating oil bath, so as to create a controlled heating environment for the asphalt pavement material together with the sample plate.

3. The method for multi-scale, multi-level evaluation of VOCs emission characteristics of asphalt pavement materials according to claim 2, characterized in that, The preset testing device also includes a sealing cover covering the sample plate, the sealing cover and the chassis forming a closed testing space, and an air inlet for introducing gas into the closed testing space is provided on the side wall of the sealing cover; A regulating valve for adjusting the gas flow rate is provided on the air inlet; A sampling port connected to the closed test space is provided on the top of the sealing cover. The gas flow channel for collecting VOCs samples of asphalt pavement material is formed by the air inlet, the regulating valve and the sampling port. This enables the preset evaluation device to collect and detect the VOCs released by the asphalt pavement material under the controlled heating environment.

4. The method for multi-scale, multi-level evaluation of VOCs emission characteristics of asphalt pavement materials according to claim 1, characterized in that, The method of uniformly characterizing the VOCs emission behavior of asphalt pavement materials at different scales based on the multi-level concentration data set specifically includes: Under simulated temperature conditions, the asphalt pavement material at different scales is heated to obtain VOCs emission concentration data corresponding to the asphalt pavement material at each scale, thereby forming an emission concentration data set. The simulated temperature conditions are constructed in the test environment based on the construction characteristics of the asphalt pavement construction project. Based on the emission concentration data set, the emission rate data of each VOCs substance under the conditions of unit time and unit asphalt mass are calculated to form an emission rate data set; Based on the emission rate data set, the emission amount of each VOCs substance within the monitoring time range is calculated to form an emission data set. The VOCs substances are then classified into components according to their chemical structure characteristics and chemical bond types, so that VOCs substances belonging to the same component form a component set. The emission data of each VOCs substance in the component set is accumulated to obtain the component emission data. At the same time, the component emission data obtained under different temperature conditions are summarized and accumulated to obtain the total VOCs emission data during the asphalt pavement construction stage. Based on the emission concentration data set, the emission rate data set, and the total VOCs emission data, and combined with four scales (asphalt, asphalt mastic, asphalt mortar, and asphalt mixture) and three levels (total concentration, component concentration, and monomer concentration), the VOCs emission behavior of asphalt pavement materials is uniformly characterized to form VOCs emission characteristic representation results of emission concentration, emission rate, and total emission.

5. The method for multi-scale, multi-level evaluation of VOCs emission characteristics of asphalt pavement materials according to claim 4, characterized in that, Before uniformly characterizing the VOCs emission behavior of asphalt pavement materials at different scales based on the multi-level concentration data set, thereby obtaining the VOCs emission characteristic representation results corresponding to the asphalt pavement materials at each scale, the method further includes: The multi-scale sample set is constructed using uniform asphalt quality as the test benchmark. Under the uniform asphalt quality benchmark, asphalt concrete is constructed into compacted asphalt concrete samples and loose asphalt concrete samples. The compacted asphalt concrete samples are prepared with a regular geometric structure that matches the sample plate of the heated oil bath to ensure uniform heating. At the same time, the loose asphalt concrete samples are uniformly spread on the surface of the bearing carrier under uniform quality conditions. Under the unified asphalt quality benchmark, the amount of asphalt in the asphalt mortar is determined according to the asphalt-aggregate ratio of the asphalt concrete, and compacted asphalt mortar samples and loose asphalt mortar samples are constructed. The compacted asphalt mortar samples maintain the same compacted structure as the compacted asphalt concrete samples, while the loose asphalt mortar samples are spread on the surface of the bearing carrier under the same quality conditions. Under the unified asphalt quality standard, the ratio of asphalt to mineral powder in asphalt mastic is determined according to the asphalt-aggregate ratio and the powder-binder ratio, and the asphalt mastic is prepared into a thin film structure to form an asphalt mastic sample. The amount of asphalt sample used is determined under the unified asphalt quality standard, and the asphalt sample is prepared as a thin film structure, thereby forming a multi-scale sample set covering asphalt, asphalt mastic, asphalt mortar and asphalt concrete under the unified asphalt quality standard.

6. The method for multi-scale, multi-level evaluation of VOCs emission characteristics of asphalt pavement materials according to claim 3, characterized in that, The method, based on a pre-set testing device, conducts VOCs emission concentration detection on a multi-scale sample set under simulated typical road conditions, specifically including: The asphalt pavement materials of different sizes are placed sequentially on the sample plate, so that the asphalt pavement materials are in contact with the heated surface of the sample plate; The target temperature of the oil bath medium inside the heating oil bath is set by the temperature controller, and the heating tube is driven by the temperature controller to increase the temperature of the oil bath medium. The heat dissipation strips are arranged to achieve uniform heat transfer between the heating oil bath and the sample plate, thereby creating a stable and uniform heating environment for the sample plate. Gas is introduced into the closed test space formed by the sealing cover and the chassis through the air inlet, and the gas flow rate is regulated by the regulating valve set on the air inlet to form a stable displacement atmosphere inside the closed test space. At the same time, the sampling port set on the top of the sealing cover is kept in the gas collection state to form a gas flow channel for exporting VOCs released from asphalt pavement materials. Under the condition of forming a stable displacement atmosphere in the closed test space, the asphalt pavement material continuously releases VOCs under the heating effect of the sample plate. Under the condition of continuous gas supply at the air inlet and gas flow control by the regulating valve, the gas inside the closed test space maintains continuous flow and stable displacement, thereby forming a dynamic gas environment for the released VOCs in the closed test space. The gas inside the closed test space is extracted through the sampling port to obtain a VOCs gas sample released by the asphalt pavement material under the current heating conditions.

7. The method for multi-scale, multi-level evaluation of VOCs emission characteristics of asphalt pavement materials according to claim 4, characterized in that, The process of calculating the emission rate data of each VOC substance per unit time and per unit mass of asphalt based on the emission concentration data set to form an emission rate data set specifically includes: The emission concentration data of the same VOCs substance obtained from each sampling are averaged to obtain the average emission concentration data within the monitoring time range. The average emission concentration data is multiplied by the VOCs emission volume per unit monitoring time under the simulated temperature environment to obtain the emission data of VOCs under the unit time condition. The emission data is then compared with the mass of asphalt material tested under the simulated temperature environment to obtain the emission rate data of the VOCs under the conditions of unit time and unit mass of asphalt, thereby forming the emission rate data set.

8. A multi-scale, multi-level evaluation device for VOCs emission characteristics of asphalt pavement materials, characterized in that, The device is used to perform a multi-scale, multi-level evaluation method for VOCs emission characteristics of asphalt pavement materials as described in any one of claims 1-7. The device includes an acquisition module, a processing module, and an output module, wherein: The acquisition module is used to detect VOCs emission concentrations on a multi-scale sample set under simulated typical road conditions based on a preset evaluation device, and to analyze the VOCs emission concentration data at three levels: total concentration, component concentration, and individual substance concentration, so as to form a multi-level concentration data set corresponding to asphalt pavement materials at different scales. The processing module is used to uniformly characterize the VOCs emission behavior of asphalt pavement materials at different scales based on the multi-level concentration data set, thereby obtaining the VOCs emission characteristic characterization results corresponding to the asphalt pavement materials at each scale. The output module is used to perform correlation analysis on the VOCs emission patterns among asphalt pavement materials at different scales based on the VOCs emission characteristic characterization results, thereby completing the cross-scale comprehensive analysis and evaluation of the VOCs emission characteristics of asphalt-based materials.

9. An electronic device, characterized in that, The device includes a processor, a communication bus, a user interface, a network interface, and a memory. The memory is used to store instructions. The user interface and the network interface are both used to communicate with other devices. The communication bus is used to enable communication between the components within the electronic device. The processor is used to execute the instructions stored in the memory to cause the electronic device to perform the method as described in any one of claims 1-7.

10. A non-transitory computer-readable storage medium, characterized in that, The computer-readable storage medium stores instructions that, when executed, perform the method as described in any one of claims 1-7.

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