Method and device for simulating release of solid waste cementitious material road service environment

Abstract

The application discloses a kind of solid waste cementing material road service environment release simulation method and device. It is related to the field of road engineering environmental safety evaluation and solid waste cementing material leaching test, method includes: in reaction cabin, from top to bottom, the multilayer medium system of surface layer, solid waste cementing material layer, underlayer and drainage layer is constructed, and water flow is made into multilayer medium system from top to bottom by intermittent water supply;Synchronous application of multiple environmental factors coupling;Different layer position effusion liquid data are obtained using the layered collection interface of reaction cabin side wall, and material internal state parameter data are obtained by internal sensor;The spatiotemporal correlation analysis is carried out to the effusion liquid data and material internal state parameter data, to evaluate the release behavior of solid waste cementing material road service environment.

Description

Technical Field

[0001] This application relates to the technical field of environmental safety assessment of road engineering and leaching test of solid waste cementitious materials, and in particular to a method and apparatus for simulating the release of solid waste cementitious materials in the road service environment. Background Technology

[0002] Solid waste-based cementitious materials, used in road base courses, subbase courses, roadbed backfill, and other road engineering structures, have become an important direction for the green and low-carbon development of road engineering. These materials have significant application value in reducing the consumption of natural resources, minimizing solid waste accumulation, and improving the utilization efficiency of engineering materials. However, bulk industrial solid waste usually contains a certain amount of soluble components and potentially harmful elements. During the long-term service of roads, these components may be leached and released due to factors such as rainfall infiltration, groundwater action, temperature and humidity cycles, carbonization, salt erosion, and traffic loads, and may migrate into the surrounding soil or groundwater environment with the water. Therefore, accurately evaluating the environmental release behavior of solid waste cementitious materials under road service conditions is of great significance for promoting the safe and resource-based utilization of bulk industrial solid waste in road engineering.

[0003] In related technologies, the evaluation methods for material leaching or seepage mainly include static immersion tests, batch leaching tests, and dynamic column filtration tests. Although these methods can evaluate the release risk of soluble components in materials to a certain extent, their test conditions still differ significantly from the actual service conditions of roads. In addition, the actual road structure is not a single homogeneous medium, but a multi-layered system composed of surface layer, base layer, subbase layer, subgrade, or backfill structure. Ions or potentially harmful elements released from solid waste cementing materials may be blocked, adsorbed, diluted, precipitated, or redistributed by different structural layers during their downward migration. In related test systems, a single sample or homogeneous column is usually used as the object, and only terminal leachate is collected, which makes it difficult to reveal the migration path and spatial distribution of pollutants within the multi-layered structure of the road. At the same time, related technologies do not adequately consider the coupling effects of multiple fields such as rainfall, salinity, carbon dioxide, temperature and humidity cycles, and loads, and also lack in-situ monitoring methods for state parameters such as pH value, moisture content, temperature, and conductivity within the material. Summary of the Invention

[0004] This application provides a method and apparatus for simulating the environmental release of solid waste cementing materials during road service, in order to solve the following technical problem: how to achieve dynamic monitoring and evaluation of the pollutant release behavior of solid waste cementing materials under real service conditions, so as to significantly improve the accuracy of environmental release prediction and engineering applicability.

[0005] In a first aspect, embodiments of this application provide a method for simulating the release of solid waste cementitious materials into the road service environment, the method comprising: The reaction chamber is configured from top to bottom as a surface layer, a solid waste cementing material layer, a subfloor layer, and a drainage layer, resulting in a multi-layered media system that simulates a road structure. Intermittent water supply is provided to the multi-layer media system, allowing water to flow into the multi-layer media system from top to bottom; In the multi-layered media system, multiple environmental factors are coupled together, including at least two of the following: temperature and humidity changes, carbon dioxide action, salt erosion, and mechanical load. Data on the exudate from different layers of the multilayer media system is acquired through a layered acquisition interface located on the side wall of the reaction chamber. Data on the internal state parameters of the material are acquired through sensors inside the multilayer media system. The exudate data includes the pH value, conductivity, ion concentration, and concentration of potentially harmful elements of the exudate. The data on the internal state parameters of the material includes the pH value, water content, temperature, and conductivity. Based on the leachate data and the internal state parameter data of the material, the environmental release behavior of the solid waste cementing material in road service is evaluated. The evaluation includes calculating the cumulative release of pollutants, the release flux per unit area, the interlayer retention rate, and / or the release response relationship.

[0006] Secondly, this application also provides a simulation device for the release of solid waste cementing materials in the road service environment. The device includes a reaction chamber, a rain spray module, a gas control module, a temperature and humidity control module, a salt solution input module, a loading module, a leachate collection module, and a control and data acquisition module. The reaction chamber is a closed or semi-closed container structure, and the reaction chamber is arranged from top to bottom as a surface layer, a solid waste cementing material layer, a lower layer and a drainage layer. The rainfall spray module is located on the upper part of the reaction chamber and includes a spray module and a flow / time control module, which is used to intermittently supply water to the multi-layer media system with adjustable rainfall intensity, spray duration and intermittent time; The gas control module is connected to the reaction chamber and is used to introduce gas into the reaction chamber and regulate the gas environment. The temperature and humidity control module is connected to the reaction chamber and is used to regulate the internal temperature and humidity of the reaction chamber. The salt solution input module is connected to the rain spray module and is used to introduce a salt solution during the rain infiltration process; The loading module is located at the upper part of the reaction chamber and is used to apply vertical loads to the specimens inside the reaction chamber. The exudate collection module includes a confluence outlet located at the bottom of the reaction chamber and stratified collection interfaces located at different heights on the side wall, for performing stratified collection and confluence collection. The control and data acquisition module is connected to the rainfall spray module, the gas control module, the temperature and humidity control module, the salt solution input module, the loading module, and the exudate acquisition module, respectively, and is used to coordinate the operation of each module and acquire test data.

[0007] The method and apparatus for simulating the release of solid waste cementitious materials in road service environments provided in this application have the following beneficial effects: First, a multi-layered media system is constructed sequentially from top to bottom within the reaction chamber, consisting of a surface layer, a solid waste cementing material layer, an underlying layer, and a drainage layer. This accurately replicates the hierarchical structure of a real road, from surface layer to base layer to subbase layer to subgrade, laying a physical foundation for revealing the patterns of pollutant retention, adsorption, and redistribution between layers. Next, intermittent water supply is applied to the multi-layered media system, promoting top-to-bottom infiltration. This realistically simulates the discontinuous infiltration characteristics of natural rainfall. Maintaining the system in an unsaturated state during non-water supply periods effectively replicates the actual water movement dynamics of "rainfall-drying" in road structures. Finally, a multi-environmental coupling effect, encompassing at least two of the following: temperature and humidity changes, carbon dioxide activity, salt erosion, and mechanical loads, is simultaneously applied to the multi-layered media system. This approach overcomes the limitations of existing single-factor experiments, comprehensively reproducing the structural evolution and leaching response of solid waste materials under complex service environments. Subsequently, it utilizes layered acquisition interfaces on the sidewalls of the reaction chamber to acquire leachate data from different layers, and employs sensors embedded within the system to extract in-situ state parameters of the materials in real time. By integrating the aforementioned multi-dimensional leachate data and in-situ state parameters, it conducts an in-depth evaluation of the environmental release behavior of solid waste cemented materials. This not only quantifies the release rate and migration path of pollutants but also analyzes the intrinsic response mechanisms of environmental parameter changes and release behavior. Ultimately, it achieves dynamic monitoring and comprehensive evaluation of pollutant release behavior of solid waste cemented materials under real service conditions, significantly improving the accuracy of environmental release prediction and its engineering applicability. Attached Figure Description

[0008] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 A flowchart illustrating a method for simulating the release of solid waste cementitious materials into the road service environment, provided in an embodiment of this application; Figure 2 This is a schematic diagram of the overall structure of a road service environment release simulation device for solid waste cementitious materials provided in an embodiment of this application; Figure 3 A schematic diagram of the reaction chamber layer structure and pollutant migration profile of a solid waste cementing material road service environment release simulation device provided in this application embodiment; Figure 4 This is a schematic diagram of multi-field coupling control of a road service environment release simulation device for solid waste cementing materials provided in an embodiment of this application. Detailed Implementation

[0009] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0010] It is understood that, in the embodiments of this application, when these embodiments are applied to specific products or technologies, user permission or consent is required, and the collection, use and processing of related data must comply with relevant laws, regulations and standards.

[0011] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0012] In the following description, the terms “first, second, ...” are used merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that “first, second, ...” may be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.

[0013] Solid waste-based cementitious materials, used in road base courses, subbase courses, roadbed backfill, and other road engineering structures, have become an important direction for the green and low-carbon development of road engineering. These materials have significant application value in reducing the consumption of natural resources, minimizing solid waste accumulation, and improving the utilization efficiency of engineering materials. However, bulk industrial solid waste usually contains a certain amount of soluble components and potentially harmful elements. During the long-term service of roads, these components may be leached and released due to factors such as rainfall infiltration, groundwater action, temperature and humidity cycles, carbonization, salt erosion, and traffic loads, and may migrate into the surrounding soil or groundwater environment with the water. Therefore, accurately evaluating the environmental release behavior of solid waste cementitious materials under road service conditions is of great significance for promoting the safe and resource-based utilization of bulk industrial solid waste in road engineering.

[0014] In related technologies, the evaluation methods for material leaching or extraction mainly include static immersion tests, batch leaching tests, and dynamic columnar infiltration tests. Although these methods can evaluate the release risk of soluble components in materials to a certain extent, their test conditions still differ significantly from the actual service conditions of roads. For example, static immersion or batch leaching tests are mostly conducted under conditions of complete immersion or forced leaching, which makes it difficult to reflect the unsaturated, intermittent, top-down water migration characteristics in road structures dominated by rainfall infiltration. Dynamic columnar tests mostly use continuous flow or saturated flow conditions, which also makes it difficult to simulate the complex seepage process under the alternating effects of "rainfall-infiltration-drainage-drying" in actual roads.

[0015] Furthermore, actual road structures are not single homogeneous media, but multi-layered systems composed of surface layers, base layers, subbase layers, roadbeds, or backfill structures. Ions or potentially harmful elements released from solid waste cementing materials may be impeded, adsorbed, diluted, precipitated, or redistributed by different structural layers during their downward migration. In relevant test systems, a single sample or homogeneous column is usually used as the object, and only terminal leachate is collected, making it difficult to reveal the migration path and spatial distribution of pollutants within the multi-layered structure of the road. At the same time, related technologies do not adequately consider the coupling effects of multiple fields such as rainfall, salinity, carbon dioxide, temperature and humidity cycles, and loads, and also lack in-situ monitoring methods for state parameters such as pH, moisture content, temperature, and conductivity within the materials.

[0016] Based on this, the embodiments of this application provide a method for simulating the environmental release of solid waste cementing materials in road service, which can realize the dynamic monitoring and evaluation of the pollutant release behavior of solid waste cementing materials under real service conditions, thereby significantly improving the accuracy of environmental release prediction and engineering applicability.

[0017] The technical solutions proposed in the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0018] Figure 1 This application provides a flowchart of a method for simulating the environmental release of solid waste cementing materials during road service. This method can be applied to various scenarios involving the use of large quantities of industrial solid waste in road engineering and requiring assessment of its environmental safety, such as evaluation of road base and subbase materials, roadbed backfilling and treatment projects, special climate and sensitive environmental areas, structures and impermeable layers under solid waste sites, and compliance certification of green and low-carbon building materials.

[0019] like Figure 1 As shown in the embodiment of this application, a method for simulating the release of solid waste cementitious materials into the road service environment specifically includes the following steps: Step 101: In the reaction chamber, from top to bottom, a surface layer, a solid waste cementing material layer, a subfloor layer, and a drainage layer are sequentially configured to obtain a multi-layered media system simulating a road structure.

[0020] Here, a solid waste cementitious material layer is prepared according to the road engineering design compaction degree, moisture content, molding pressure, or on-site construction compaction conditions. Based on the actual road structure, a surface module, a solid waste cementitious material layer, an underlying layer module, and a drainage module are sequentially set in the reaction chamber to form a layered reaction system for simulating the multi-layer structure of a road. The solid waste cementitious material layer can be formed by integral filling or by combining several compacted molding specimens or standard specimens. The underlying layer module can use sand, graded crushed stone, recycled granular materials, or other porous media to simulate the downward migration, retention, and redistribution of pollutants in the actual road structure.

[0021] In some embodiments, after obtaining the multi-layered media system of the simulated road structure by performing step 101, it is also necessary to set conditions such as rainfall intensity and intermittent period, temperature and humidity variation, carbon dioxide concentration, salt concentration, and load application mode according to the actual road service environment, so as to ensure that the simulated environment is consistent with the actual road.

[0022] Step 102: Intermittently supply water to the multi-layer media system, so that the water flows into the multi-layer media system from top to bottom.

[0023] In some embodiments, the water flow of the intermittent water supply is uniformly distributed and the rainfall intensity, spray duration, and interval time are adjustable to simulate the discontinuous infiltration characteristics during natural rainfall.

[0024] In some embodiments, the multilayer media system is kept unsaturated during the interval between two adjacent water supplies and after the water supply ends, in order to simulate the rain-drying cycle of a real road.

[0025] Here, intermittent water supply is carried out through a rainfall infiltration simulation module, allowing water to flow from top to bottom into the material system (multi-layer media system). During the non-water supply phase, the material system is kept in an unsaturated state to simulate the rainfall-drying cycle process in actual roads.

[0026] Step 103: Apply the coupling effect of multiple environmental factors to the multi-layered media system. The multiple environmental factors include at least two of the following: temperature and humidity changes, carbon dioxide action, salt erosion, and mechanical load.

[0027] Here, during the experiment, at least two of the following are applied simultaneously: temperature change or wet-dry cycle, carbon dioxide action, salt erosion, and mechanical load, in order to achieve the coupled effect of multiple environmental factors.

[0028] In some embodiments, the effect of carbon dioxide includes controlling the carbonization process of the multilayer media system by adjusting the gas concentration to simulate the impact of carbon dioxide intrusion on actual roads.

[0029] Step 104: Obtain the exudate data of different layers of the multi-layer media system through the layered acquisition interface set on the side wall of the reaction chamber.

[0030] Here, the exudate data includes the pH value, conductivity, ion concentration, and concentration of potentially harmful elements in the exudate.

[0031] During the experiment, leachate was collected at set time intervals. Layered collection interfaces located at different heights on the side wall of the reaction chamber were used to collect leachate from the corresponding layers of the solid waste cementing material layer, the underlying layer, or the drainage layer. Terminal leachate that had migrated through each structural layer was collected through the bottom drainage outlet and the leachate collection container.

[0032] Step 105: Obtain material internal state parameter data through sensors inside the multilayer media system.

[0033] Here, the internal state parameters of the material include pH value, moisture content, temperature, and electrical conductivity; the internal state of the material is monitored in real time by sensors installed in the reaction chamber to obtain dynamic change data during the leaching process.

[0034] Step 106: Based on the leachate data and the internal state parameter data of the material, evaluate the environmental release behavior of the solid waste cementing material in road service.

[0035] Here, the pH value, conductivity, ion concentration, and concentration of potentially harmful elements in the collected leachate are measured to analyze the release, migration, retention, and redistribution characteristics of pollutants in different structural layers. Based on the leachate data and in-situ monitoring data, the release rate, migration path, and spatial distribution characteristics of pollutants are analyzed to achieve a comprehensive evaluation of the material's environmental release behavior. The evaluation includes calculating the cumulative release amount of pollutants, release flux per unit area, interlayer retention rate, and / or release response relationship.

[0036] In some embodiments, step 106 described above can be implemented by performing spatiotemporal correlation analysis on the leachate data and the internal state parameter data of the material to obtain the response relationship between pollutant release, migration, redistribution and changes in environmental parameters, so as to achieve a comprehensive evaluation of the environmental release behavior of the solid waste cementing material in road service.

[0037] In some embodiments, the above Figure 1 The method shown is a simulation method for the environmental release of solid waste cementing materials during road service. Figure 2 This illustrates a simulation device for the release of solid waste cementitious materials into the road service environment. (See attached image) Figure 2 , Figure 2This is a schematic diagram of the overall structure of a road service environment release simulation device for solid waste cementitious materials provided in an embodiment of this application, as shown below. Figure 2 As shown in the figure, this application provides a simulation device for the release of solid waste cementing materials in the road service environment. The device includes a reaction chamber 201, a rain spray module 202, a gas control module 203, a temperature and humidity control module 204, a salt solution input module 205, a loading module 206, a leachate collection module 207, and a control and data acquisition module.

[0038] See Figure 3 , Figure 3 A schematic diagram of the reaction chamber layered structure and pollutant migration profile of a road service environment release simulation device for solid waste cementing materials provided in this application embodiment is shown below. Figure 3 As shown, the reaction chamber 201 is a closed or semi-closed container structure. The reaction chamber is arranged from top to bottom as a surface layer 2011, a solid waste cementing material layer 2012, a lower layer 2013, and a drainage layer 2014.

[0039] Here, the surface layer 2011 is a permeable medium used to simulate the infiltration area of ​​the upper part of the road structure and serves as the initial layer for rainwater or saline solution to enter the test system; the solid waste cementing material layer 2012 is a red mud concrete specimen, a multi-source solid waste cementing material specimen, or an integral filling structure used to simulate the service layer of road base, backfill material, or other solid waste cementing materials. It can be an integral filling structure or a combination of several compacted specimens or standard specimens; the underlying layer 2013 is sand, graded crushed stone, or recycled granular material, located below the solid waste cementing material layer, used to simulate the influence of the underlying layer or surrounding medium on the migration, retention, adsorption, and redistribution of pollutants in the actual road structure; the drainage layer 2014 is located at the bottom of the reaction chamber 201 and is connected to the leachate collection module 207, used to collect the leachate after it has migrated through each structural layer.

[0040] See also Figure 2 The rainfall spray module 202 is located on the upper part of the reaction chamber 201 and includes a spray module and a flow control module. It is used to intermittently supply water to the multi-layer media system with adjustable rainfall intensity, spray duration and intermittent time.

[0041] See also Figure 2 The gas control module 203 is connected to the reaction chamber 201 and is used to introduce gas into the reaction chamber 201 and regulate the gas environment. Here, the gas control module is preferably a carbon dioxide supply module, which controls the carbonization process of the material by adjusting the gas concentration, so as to simulate the effect of carbon dioxide intrusion on the material structure and leaching behavior in the actual environment.

[0042] See also Figure 2The temperature and humidity control module 204 is connected to the reaction chamber 201 and is used to regulate the temperature and humidity inside the reaction chamber.

[0043] In some embodiments, the temperature and humidity control module includes a temperature control module and a humidity control module; the temperature control module includes a temperature sensor and a heating module, the heating module including at least one of a heating plate, an electric heating film, and a heating wire; the humidity control module includes a humidity sensor and a humidification module, the humidification module including one of a liquid storage and water replenishment structure, an atomizing humidification structure, and a permeation humidification structure.

[0044] Here, the temperature and humidity control module 204 includes a control layer disposed at the bottom of the reaction chamber 201, and an external control module connected to the control layer, used to receive signals collected by the temperature sensor and humidity sensor, and to coordinately adjust the heating module and the humidification module. The temperature control module is used to adjust the internal ambient temperature of the reaction chamber 201, and the humidity control module is used to adjust the internal ambient humidity of the reaction chamber 201; the temperature control module includes a temperature sensor and a heating module, preferably one or more of a heating plate, an electric heating film, or a heating wire; the humidity control module includes a humidity sensor and a humidification module, preferably a liquid storage and water replenishment structure, an atomizing humidification structure, or a permeation humidification structure; the external control module is connected to the temperature sensor and the humidity sensor respectively, and is used to adjust the heating module and the humidification module according to the collected temperature and humidity signals.

[0045] See also Figure 2 The salt solution input module 205 is connected to the rain spray module 202 and is used to introduce salt solution during the rain infiltration process.

[0046] Here, the salt solution input module 205 is used to introduce a salt solution during the rain infiltration process and cooperate with the rain spray module 202 to form a salt spraying condition. The salt solution may include chloride salts or other common environmental salts. It is used to simulate the effects of winter road de-icing salt or snow melting salt infiltration with rain and snow melting water on the release, migration and leaching process of soluble components and potential harmful elements in solid waste cementing materials. It can also be used to simulate the effect of saline groundwater environment on the leaching behavior of materials.

[0047] See also Figure 2 The loading module 206 is located at the top of the reaction chamber and is used to apply vertical loads to the specimens inside the reaction chamber.

[0048] In some embodiments, the loading module 206 includes a drive module, a loading rod, a sealing guide structure, and a loading head or loading plate; the drive module is disposed above the reaction chamber; the loading rod passes through the top of the reaction chamber and is connected to the reaction chamber through the sealing guide structure, and the loading head or loading plate is disposed at the lower end of the loading rod.

[0049] Here, the loading module 206 is located on the upper part of the reaction chamber 201 and is used to apply a vertical load to the solid waste cemented material specimen to be tested inside the reaction chamber 201. The loading module includes a drive module located above the reaction chamber 201, a loading rod connected to the drive module, a sealed guide structure located on the top of the reaction chamber, and a loading head or loading plate located inside the reaction chamber 201. The loading rod passes through the top of the reaction chamber and is connected to the reaction chamber through the sealed guide structure. The loading head or loading plate is located at the lower end of the loading rod and is used to transfer the load generated by the drive module to the solid waste cemented material specimen to be tested. The load can be a static load, a graded load, or a periodic dynamic load to simulate the evolution of the internal structure of the material under the action of the overlying structure and traffic load during road service and its impact on the seepage path.

[0050] See also Figure 2 The exudate collection module 207 includes a confluence outlet located at the bottom of the reaction chamber 201 and layered collection interfaces located at different heights on the side wall, for performing layered collection and confluence collection.

[0051] Here, the leachate collection module 207 is located at the bottom and side of the reaction chamber 201, and is used to collect the leachate generated during the leaching process in layers and by confluence. The leachate collection module 207 includes a bottom drain outlet, a leachate collection container, and layered collection interfaces located at different heights on the side wall of the reaction chamber. The bottom drain outlet is used to collect the terminal leachate after it has migrated through the surface layer 2011, the solid waste cementing material layer 2012, and the underlying layer 2013. The layered collection interfaces are used to collect leachate from different structural layers or different depths to obtain information on the release, migration, retention, and redistribution of pollutants in different structural layers. The layered collection interfaces include a porous sampling head, a filter membrane / screen, a sampling pipeline, a valve, and a collection container. The porous sampling head is located at the interface of adjacent structural layers or inside the target layer. The filter membrane / screen is used to block solid particles from entering the sampling pipeline. Each layered sampling interface is independent of the others.

[0052] See also Figure 3 The solid waste cementing material road service environment release simulation device also includes an in-situ monitoring module 209; the in-situ monitoring module 209 is set at the solid waste cementing material layer 2012, the underlying layer 2013, the drainage layer 2014 or the interlayer interface, and is used to obtain the internal state parameters of the material at different layers. The in-situ monitoring module 209 includes at least one of a pH sensor, a moisture content sensor, a temperature sensor and a conductivity sensor.

[0053] Here, the in-situ monitoring module 209 is deployed at different structural layers and depths inside the reaction chamber 201 to monitor changes in internal environmental parameters of the material in real time during the leaching process. The in-situ monitoring module 209 includes one or more of the following: pH sensor, moisture content sensor, temperature sensor, and conductivity sensor. The in-situ monitoring module 209 can be set at the solid waste cementing material layer 2012, the underlying layer 2013, the drainage layer 2014, or the interlayer interface to obtain dynamic parameters such as pH value, moisture content, temperature, and conductivity at different layers. By deploying the in-situ monitoring module 209 at multiple points, dynamic tracking of water migration, salt migration, pollutant release, and changes in environmental parameters during the leaching process can be achieved.

[0054] In some embodiments, see Figure 4 , Figure 4 This is a schematic diagram of multi-field coupling control of a road service environment release simulation device for solid waste cementing materials provided in an embodiment of this application, as shown below. Figure 4 As shown, the solid waste cementing material road service environment release simulation device also includes a control and data acquisition module 208.

[0055] The control and data acquisition module 208 is connected to the rain spray module 202, the gas control module 203, the temperature and humidity control module 204, the salt solution input module 205, the loading module 206, and the in-situ monitoring module 209, respectively, and is used to coordinate the operation of each module and collect test data.

[0056] Here, the control and data acquisition module 208 includes a control module and a data acquisition module; the control module is used to adjust the spray intensity, spray duration, salt solution input concentration and flow rate, gas concentration, temperature and humidity conditions, and loading method; the data acquisition module is used to receive and record parameters such as pH value, water content, temperature, and conductivity collected by the in-situ monitoring module 209, as well as the leachate detection data obtained by the leachate collection module 207; through the control and data acquisition module 208, the automatic control, synchronous recording, and dynamic evaluation of the multi-field coupled leaching test process can be realized.

[0057] Through the above structure, the rainfall spray module 202 and the salt solution input module 205 are used to provide pure water or salt-containing infiltration conditions into the reaction chamber 201; the gas control module 203 is used to create a controllable gas environment; the temperature and humidity control module 204 is used to regulate the temperature and humidity environment; the loading module 206 is used to apply vertical loads; the leachate collection module 207 and the in-situ monitoring module 209 are used to collect migration results and monitor process parameters, respectively; and the control and data acquisition module 208 is used to realize the coordinated control of each module and the synchronous recording of data. Therefore, this device can simulate the environmental release of solid waste cementing materials under the coupled effects of multiple fields such as water, gas, salt, temperature and humidity, and load in the same reaction system.

[0058] Based on this, this application proposes a method and apparatus for simulating the release of solid waste cementitious materials into the road service environment, which has at least the following beneficial effects: (1) It can more realistically simulate the unsaturated intermittent infiltration process in road structures. Existing static immersion tests or continuous flow column tests are usually difficult to reflect the intermittent, unsaturated and top-down migration characteristics of rainfall infiltration during actual road service. This application provides controllable spray water flow to the reaction chamber 201 through the rainfall spray module 202, and can adjust the rainfall intensity, spray duration and interval time, thereby simulating the water migration process of "rainfall-infiltration-stop-re-infiltration" in actual roads, making the test conditions closer to the road service environment, thereby improving the authenticity and engineering applicability of the solid waste cementing material leaching test results; (2) It can realize the simulation of environmental release under the coupled effect of multiple environmental factors. In the actual service process of roads, solid waste cementing materials are usually affected by multiple factors such as rainwater infiltration, de-icing salt or saline groundwater erosion, carbon dioxide intrusion, temperature and humidity cycle, as well as overlying structures and traffic loads. Compared with the existing single-factor or few-factor leaching test methods, this application can reproduce the multi-field coupled environment of water, gas, salt, temperature and humidity and load in the same test system through the synergistic effect of the rainwater spray module 202, gas control module 203, temperature and humidity control module 204, salt solution input module 205 and loading module 206, so as to more comprehensively reflect the structural evolution and pollutant release behavior of solid waste cementing materials under complex service conditions; (3) It can effectively simulate the impact of de-icing salt, snow melting salt and saline groundwater on the environmental release behavior of solid waste cementing materials in winter. By cooperating with the salt solution input module 205 and the rain spray module 202, different working conditions such as pure water spray, saline solution spray and simultaneous input of rainwater and salt solution can be formed to simulate the impact of de-icing salt or snow melting salt on the release, migration and leaching process of soluble components and potential harmful elements in solid waste cementing materials after infiltration with rainwater and snow melting water. This setting can enhance the adaptability of the test conditions to the road service environment and saline groundwater environment in cold regions; (4) It can more realistically reflect the impact of the multi-layer structure of the road on the migration, retention and redistribution of pollutants. The actual road structure is usually composed of multiple layers of materials such as surface layer, base layer, subbase layer, roadbed or backfill structure. The pore characteristics, water content, adsorption capacity and drainage conditions of different layers are different, which will have the effects of hindrance, adsorption, dilution, precipitation or redistribution on the migration of soluble components and potential harmful elements in solid waste cementing materials. This application sets a surface layer 2011, a solid waste cementing material layer 2012, a subfloor layer 2013 and a drainage layer 2014 inside the reaction chamber 201, which can simulate the layer-by-layer migration process of pollutants in the multi-layer structure of the road. Compared with the traditional method of using only a single homogeneous sample and analyzing the terminal leachate, this application can simultaneously obtain information on different layers and terminal leachate, so that the environmental release assessment is expanded from a single result assessment to a comprehensive assessment of "layer migration-process monitoring-terminal release", thereby improving the authenticity and refinement of the environmental safety assessment of solid waste cementing materials for road use. (5) It can realize the stratified collection and confluence collection of leachate. The leachate collection module 207 includes a bottom drainage outlet, a leachate collection container and stratified collection interfaces set at different heights on the side wall of the reaction chamber 201. It can collect terminal leachate and leachate at different structural layers or different depths. By detecting the pH value, conductivity, ion concentration and potential harmful element concentration of leachate at different collection locations, the release, migration, retention and redistribution of pollutants in each structural layer can be evaluated more accurately, thereby improving the completeness and refinement of environmental release behavior evaluation. (6) In-situ dynamic monitoring of internal state parameters of materials can be realized during leaching. The in-situ monitoring module 209 can be deployed at the solid waste cementing material layer 2012, the underlying layer 2013, the drainage layer 2014 or the interlayer interface to obtain parameters such as pH value, moisture content, temperature and conductivity in real time. Compared with the traditional evaluation method that only relies on the detection of leachate after the test, this application can simultaneously obtain data on changes in the internal environment during the leaching process, which helps to reveal the relationship between water migration, salt migration, pollutant release and the evolution of the internal state of the material, thereby improving the reliability of leaching mechanism analysis. (7) The leaching and release behavior of solid waste cementitious materials can be evaluated under load. The loading module 206 transmits static load, graded load or periodic dynamic load to the solid waste cementitious material layer to be tested inside the reaction chamber 201 through the drive module, loading rod, sealed guide structure and loading head or loading plate, thereby simulating the pressure of the overlying structure and traffic load during road service. This setting can reflect the influence of the internal pore structure, crack development and seepage path change of the material on the pollutant release behavior under load, so that the test results are more consistent with the actual road stress service state; (8) The control and data acquisition module 208 is used to coordinate the control of each functional module and to synchronously record the in-situ monitoring data and the exudate detection data. The control and data acquisition module 208 can adjust the spray intensity, spray duration, salt solution input concentration and flow rate, gas concentration, temperature and humidity conditions and loading method, and record the pH value, water content, temperature, conductivity and exudate detection results; thereby, this application can improve the automation level of the test process, the accuracy of working condition control and the integrity of data recording, reduce human operation error, and thus improve the repeatability and comparability of test results; (9) The modular structure design allows each functional module to be combined or adjusted independently according to different road service environments, different types of solid waste cementing materials, and different evaluation requirements. For example, it can conduct rainfall infiltration and leaching tests alone, or it can conduct rainfall-salt, rainfall-carbonization, rainfall-temperature and humidity cycle, rainfall-load, or multi-factor coupling tests. This modular design can improve the applicability and flexibility of the device, and is conducive to conducting environmental release assessments for different regions, different climate conditions, and different road engineering application scenarios. In summary, this application, by constructing a hierarchical reaction system and integrating functional modules such as rainfall spraying, gas control, temperature and humidity regulation, salt solution input, loading, leachate collection, in-situ monitoring, and data acquisition and control, can realistically simulate the environmental release behavior of solid waste cementitious materials under road service conditions. Compared with existing technologies, this application has significant advantages in terms of experimental environment realism, multi-field coupling degree, pollutant migration process characterization, in-situ monitoring capability, data acquisition completeness, and experimental controllability. It can provide more reliable technical support for the environmental safety assessment and engineering application of red mud concrete, multi-source solid waste cementitious materials, and other solid waste-based road materials.

[0059] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0060] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A method for simulating the release of solid waste cementitious materials into the road service environment, characterized in that, The method includes: The reaction chamber is configured from top to bottom as a surface layer, a solid waste cementing material layer, a subfloor layer, and a drainage layer, resulting in a multi-layered media system that simulates a road structure. Intermittent water supply is provided to the multi-layer media system, allowing water to flow into the multi-layer media system from top to bottom; In the multi-layered media system, multiple environmental factors are coupled together, including at least two of the following: temperature and humidity changes, carbon dioxide action, salt erosion, and mechanical load. Data on the exudate from different layers of the multilayer media system is acquired through a layered acquisition interface located on the side wall of the reaction chamber. Data on the internal state parameters of the material are acquired through sensors inside the multilayer media system. The exudate data includes the pH value, conductivity, ion concentration, and concentration of potentially harmful elements of the exudate. The data on the internal state parameters of the material includes the pH value, water content, temperature, and conductivity. Based on the leachate data and the internal state parameter data of the material, the environmental release behavior of the solid waste cementing material in road service is evaluated. The evaluation includes calculating the cumulative release of pollutants, the release flux per unit area, the interlayer retention rate, and / or the release response relationship.

2. The method according to claim 1, characterized in that, The intermittent water supply has a uniform water flow and adjustable rainfall intensity, spray duration, and interval time to simulate the discontinuous infiltration characteristics during natural rainfall.

3. The method according to claim 1, characterized in that, During the intervals between two consecutive water supply operations and after the water supply ends, the multi-layer media system is kept in an unsaturated state to simulate the rain-drying cycle of a real road.

4. The method according to claim 1, characterized in that, The carbon dioxide effect includes controlling the carbonization process of the multilayer media system by adjusting the gas concentration to simulate the impact of carbon dioxide intrusion on actual roads.

5. The method according to claim 1, characterized in that, The evaluation of the environmental release behavior of the solid waste cementing material in road service, based on the leachate data and the internal state parameter data of the material, includes: Spatiotemporal correlation analysis was performed on the leachate data and the internal state parameter data of the material to obtain the response relationship between pollutant release, migration, redistribution and changes in environmental parameters, so as to achieve a comprehensive evaluation of the environmental release behavior of the solid waste cementing material in road service.

6. A device for simulating the release of solid waste cementitious materials into the road service environment, characterized in that, The device includes a reaction chamber, a rain spray module, a gas control module, a temperature and humidity control module, a salt solution input module, a loading module, an exudate collection module, and a control and data acquisition module. The reaction chamber is a closed or semi-closed container structure, and the reaction chamber is arranged from top to bottom as a surface layer, a solid waste cementing material layer, a lower layer and a drainage layer. The rainfall spray module is located on the upper part of the reaction chamber and includes a spray module and a flow control module, used to intermittently supply water to the multi-layer media system with adjustable rainfall intensity, spray duration and intermittent time; The gas control module is connected to the reaction chamber and is used to introduce gas into the reaction chamber and regulate the gas environment. The temperature and humidity control module is connected to the reaction chamber and is used to regulate the internal temperature and humidity of the reaction chamber. The salt solution input module is connected to the rain spray module and is used to introduce a salt solution during the rain infiltration process; The loading module is located at the upper part of the reaction chamber and is used to apply vertical loads to the specimens inside the reaction chamber. The exudate collection module includes a confluence outlet located at the bottom of the reaction chamber and stratified collection interfaces located at different heights on the side wall, for performing stratified collection and confluence collection. The control and data acquisition module is connected to the rainfall spray module, the gas control module, the temperature and humidity control module, the salt solution input module, the loading module, and the exudate acquisition module, respectively, and is used to coordinate the operation of each module and acquire test data.

7. The apparatus according to claim 6, characterized in that, The surface layer is a permeable medium used to simulate the infiltration area of ​​the upper part of the road structure; the solid waste cementing material layer is a red mud concrete specimen, a multi-source solid waste cementing material specimen, or an integral filling structure; the underlying layer is sand, graded crushed stone, or recycled granular material, and is set below the solid waste cementing material layer; the drainage layer is set at the bottom of the reaction chamber and is connected to the leachate collection module.

8. The apparatus according to claim 6, characterized in that, The temperature and humidity control module includes a temperature control module and a humidity control module; the temperature control module includes a temperature sensor and a heating module, and the heating module includes at least one of a heating plate, an electric heating film, and a heating wire; the humidity control module includes a humidity sensor and a humidification module, and the humidification module includes one of a liquid storage and water replenishment structure, an atomizing humidification structure, and a permeation humidification structure.

9. The apparatus according to claim 6, characterized in that, The loading module includes a drive module, a loading rod, a sealing guide structure, and a loading head or loading plate; the drive module is located above the reaction chamber; the loading rod passes through the top of the reaction chamber and is connected to the reaction chamber through the sealing guide structure, and the loading head or the loading plate is located at the lower end of the loading rod.

10. The apparatus according to claim 6, characterized in that, The device further includes an in-situ monitoring module; the in-situ monitoring module is disposed at the location of the solid waste cementing material layer, the underlying layer, the drainage layer or the interlayer interface, and is used to obtain the internal state parameters of the material at different layers. The in-situ monitoring module includes at least one of a pH sensor, a moisture content sensor, a temperature sensor and a conductivity sensor.

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