Utilization method of solid waste stone powder or rock ballast based on Portland cement and alkaline oxide

Abstract

The invention relates to the technical field of building materials, and discloses a utilization method of solid waste stone powder or rock ballast based on Portland cement and alkaline oxides, which comprises the following steps: S1, material mixing: mixing solid waste stone powder or rock ballast with a magnesium oxychloride binding material according to a ratio, adding water, and mixing again to ensure that the binding material is fully dissolved, so as to obtain a mixed material; the solid waste stone powder or rock ballast is derived from solid waste dust generated in a raw material processing link of a cement plant or when a raw material with hill-skill stone and soil is produced by a self-processing stone crushing plant; and S2, forming is conducted, specifically, the magnesium oxychloride concrete obtained in the S1 is poured into a mold, demolding is conducted after the magnesium oxychloride concrete is solidified, and the concrete member is obtained. The resource utilization of the solid waste stone powder or rock ballast is realized, and the environmental pressure caused by solid waste stacking is reduced; a magnesium oxychloride cementing material is adopted to replace a traditional cement-based material, and the problems that traditional concrete is long in setting time and high in energy consumption are solved.

Description

Technical Field

[0001] This solution relates to the field of building materials technology, specifically to a method for utilizing solid waste stone powder or stone slag based on silicate cement and alkaline oxides. Background Technology

[0002] Traditional precast component materials are all concrete, with ordinary silicate cement and fly ash being among the most commonly used cementitious materials. However, these materials have many drawbacks, including long setting times, high energy consumption during preparation, environmental pollution, and high costs. Furthermore, the solid waste dust emitted by cement plants during raw material processing (crushing, belt conveying, and grinding processes) is difficult to properly handle. This solution utilizes the solid waste stone powder generated during cement plant production in precast component materials. The solid waste stone powder or stone slag is mixed with magnesium oxychloride concrete as a raw material for precast components. This approach not only enables engineering construction applications but also solves the problem of recycling and reusing solid waste materials, avoiding the pressure of environmental pollution. Summary of the Invention

[0003] The present invention aims to provide a method for utilizing solid waste stone powder or stone slag based on silicate cement and alkaline oxides, so as to make reasonable resource utilization of solid waste stone powder or stone slag and reduce the environmental pressure caused by the stockpiling of solid waste stone powder or stone slag.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a method for utilizing solid waste stone powder or stone slag based on silicate cement and alkaline oxides, comprising the following steps: S1 Mixing: Mixing solid waste stone powder or stone slag with magnesium oxychloride cementitious material according to the proportion, adding water, and mixing again to ensure that the cementitious material is fully dissolved to form magnesium oxychloride concrete, wherein the solid waste stone powder or stone slag originates from the raw material processing stage of cement plants or from solid waste dust generated when processing raw materials containing mountain stone and soil in stone crushing plants; S2 Molding: Pouring the magnesium oxychloride concrete obtained in S1 into a mold, and demolding after the magnesium oxychloride concrete has cured to obtain a concrete component.

[0005] The beneficial effects of this solution are: it realizes the resource utilization of solid waste stone powder or stone slag, reducing the environmental pressure caused by solid waste stockpiling; it uses magnesium oxychloride cementitious material to replace traditional cement-based materials, solving the problems of long setting time and high energy consumption of traditional concrete, and the prepared concrete components have excellent comprehensive performance, which is in line with the green and low-carbon concept.

[0006] Furthermore, in the S1 mixing process, the mixing equipment adopts vibration mixing technology, and the magnesium oxychloride concrete is mixed by dual vertical shaft differential vortex mixing.

[0007] Beneficial effects: Dual-shaft differential vortex mixing can combine macroscopic convection motion with microscopic diffusion motion, effectively overcoming the agglomeration phenomenon of stone powder during preparation, transportation and storage, accelerating the surrounding diffusion of stone powder and water, improving the rheological properties, workability and segregation of concrete, while shortening the mixing time and improving production efficiency.

[0008] Furthermore, during the pouring of S2, test blocks under the same conditions are reserved according to the concrete volume and shift requirements for subsequent quality testing. By reserving test blocks, the quality of concrete components can be monitored in real time, problems such as insufficient strength and performance defects can be detected in advance, and unqualified components can be avoided from being put into use, thus ensuring the stability of project quality.

[0009] Furthermore, in S1, the magnesium oxychloride cementitious material is composed of magnesium chloride, magnesium oxide and citric acid, and the particle size of solid waste stone powder or stone slag is 10-20mm. The mix proportion is calculated per cubic meter of magnesium oxychloride concrete as follows: 164kg magnesium chloride, 266kg magnesium oxide, 3kg citric acid, 1509kg solid waste stone powder or stone slag, 328kg stone chips and 131kg water. The mixing process first involves conveying solid waste stone powder or slag, magnesium oxychloride cementitious materials, and stone chips to a mixing pot via a conveyor belt and dry-mixing for 30 seconds. Then, water is added and mixed for at least 60 seconds, employing a dual-vertical-shaft differential vortex mixing technology. This precise proportioning ensures stable concrete performance. Citric acid significantly improves the water resistance and strength of magnesium oxychloride cement. The combination of dry and wet mixing further guarantees uniform material mixing, preventing performance fluctuations in components due to uneven mixing. Simultaneously, the conveyor belt enables automated material transport, reducing manual intervention.

[0010] Furthermore, in S2, before pouring, the mold is cleaned and sprayed with a release agent. During cleaning, the mold is first soaked in a 15-20% diluted oxalic acid solution for 5-10 minutes, then rinsed in a 4% detergent solution, and finally cleaned and dried in a clean water tank. The release agent is salad oil that meets edible oil standards and is evenly sprayed using an electric spray gun. During the pouring process, a self-propelled concrete placing machine is used for placement, with manual assistance for leveling. After pouring, a frequency-controlled vibrating table is used for compaction, with the vibration time controlled at around 90 seconds, until all air bubbles in the concrete are completely dissipated and the surface is smooth. The curing process includes curing and maintenance. Curing is carried out in a cool place without watering. When the temperature is below 0°C, heat preservation measures are taken. The curing period is 28 days. Demolding is carried out 24-48 hours after pouring and when the temperature is highest on that day. After demolding, the mold is covered with a curing cloth to keep it moist until the design strength is reached. Mold cleaning and release agent spraying ensure clean molds and easy demolding, preventing component adhesion to the mold and resulting appearance damage; self-propelled concrete placing boom improves placement efficiency and uniformity, while frequency conversion vibrating table compaction thoroughly removes air bubbles from the concrete, ensuring a smooth surface and dense interior; targeted curing and maintenance processes are adapted to the strength formation mechanism of magnesium oxychloride concrete, eliminating the need for water curing, reducing maintenance costs, and ensuring the strength development of components under different temperature environments, preventing surface cracking.

[0011] Furthermore, in S2, demolding is performed manually with the aid of a dedicated demolding frame. During demolding, the component is first flipped over and placed on a self-made demolding bracket, and then a rubber mallet is used to tap around the component, causing it to fall naturally from the mold. The dedicated demolding frame and the rubber mallet tapping method avoids hard impacts on the component during demolding, preventing chipped edges and surface damage, while also protecting the mold from deformation and extending its service life.

[0012] Furthermore, the process includes the S3 finished product handling step, which involves inspecting concrete components that have reached their design strength after demolding and curing. Once inspected and approved, the components are bundled on wooden pallets using a packing machine. A 3mm thick bubble wrap is placed between each layer of components for separation. The stacking height should not exceed 1.5 meters, and the number of layers should not exceed 10. After packing, classification labels are affixed, indicating the component type, model, and quantity. The components are then transported by forklift to a flat and firm storage area for classified and zoned storage. Bubble wrap separation and proper stacking prevent damage from compression and collisions during storage and transportation; classification labels and zoned storage facilitate later inventory and distribution, improving component management efficiency and reducing the risk of misuse or omission.

[0013] Furthermore, this includes S4 mix design optimization. Before mixing in S1, a portion of solid waste stone powder or slag and magnesium oxychloride cementitious material are weighed out according to the mix design as test materials. After mixing the test materials, water is added to ensure that the cementitious material is fully dissolved, thus forming magnesium oxychloride concrete. Test blocks are then made using the concrete, and the mechanical properties of the test blocks are analyzed and tested through material mechanics tests to adjust and optimize the mix design. By verifying the rationality of the mix design in advance through test blocks, the mix design can be dynamically optimized according to the characteristics of different solid waste stone powders or slags and the performance requirements of the components in the project, ensuring that the concrete components always meet the design strength and service requirements, and improving the adaptability of the technical solution.

[0014] Furthermore, mechanical testing utilizes an electromagnetically driven Hopkinson bar (SHPB) device combined with high-speed imaging (DIC) technology to evaluate the dynamic mechanical properties of the material, and static mechanical properties are assessed through static flexural and compressive strength tests. This multi-dimensional mechanical property testing provides a comprehensive understanding of the dynamic and static properties of concrete materials, offering precise data support for mix design optimization and component quality control, ensuring the safety and reliability of components under various stress scenarios. Attached Figure Description

[0015] Figure 1 This is a flowchart of an embodiment of the present invention; Figure 2 This is a schematic diagram of the Hopkinson pressure bar (SHPB) device according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the main failure modes in the dynamic mechanical test of an embodiment of the present invention.

[0016] Reference numerals: Impact rod 11, Incident rod 12, Transmission rod 13, Absorption rod 14, Computer 20, Velocimeter 21, Dynamic impact strain gauge 22, Power control system 30, Electromagnetic coil 31. Detailed Implementation

[0017] Example 1 Example 1 is basically as shown in the appendix. Figure 1 As shown, Figure 1The method for utilizing solid waste stone powder or slag based on silicate cement and alkaline oxides, as shown, includes the following steps: S1 Mixing: Solid waste stone powder or slag is mixed with magnesium oxychloride cementitious material according to the specified ratio, water is added, and the mixture is stirred again to ensure the cementitious material is fully dissolved, forming magnesium oxychloride concrete. The magnesium oxychloride cementitious material consists of magnesium chloride, magnesium oxide, and citric acid. The particle size of the solid waste stone powder or slag is 10-20 mm. The ratio, calculated per cubic meter of magnesium oxychloride concrete, is: magnesium chloride... The mixture consists of 164 kg of magnesium, 266 kg of magnesium oxide, 3 kg of citric acid, 1509 kg of solid waste stone powder or slag, 328 kg of stone chips, and 131 kg of water. The mixing equipment utilizes vibration mixing technology, employing a dual-shaft differential vortex mixer to mix the magnesium oxychloride concrete. The mixing process involves first conveying the solid waste stone powder or slag, magnesium oxychloride cementitious material, and stone chips to the mixing pot via a conveyor belt and dry-mixing for 30 seconds, then adding water and mixing for at least 60 seconds. The mixing process utilizes dual-shaft differential vortex mixing technology. S2 molding involves pouring the magnesium oxychloride concrete obtained in S1 into a mold. After the magnesium oxychloride concrete has cured, it is demolded to obtain a concrete component. During pouring, test blocks under the same conditions are reserved according to the concrete volume for subsequent quality testing. Before pouring, the mold is cleaned and sprayed with a release agent. For cleaning, the mold is first immersed in a 15-20% diluted oxalic acid solution for 5-10 minutes, then rinsed in a 4% detergent solution, and finally cleaned and dried in a clean water tank. The release agent used is salad oil that meets edible oil standards, sprayed evenly using an electric spray gun. During pouring, a self-propelled concrete placing boom is used for placement, with manual leveling. After pouring, a frequency-controlled vibrating table is used for compaction, with the vibration time controlled at 90 seconds. The curing process continues until all air bubbles in the concrete have dissipated and the surface is smooth. The curing process includes curing and maintenance. Curing is carried out in a cool place without watering. When the temperature is below 0°C, heat preservation measures are taken. The curing period is 28 days. Demolding is carried out 24-48 hours after pouring and when the temperature is highest on the day. After demolding, continue to cover with curing cloth to keep it moist until the design strength is reached. Demolding is done manually with a special demolding frame. When demolding, first turn the component upside down and place it on the self-made demolding bracket, and then gently tap along the perimeter of the component with a rubber mallet to make the component fall out of the mold naturally.

[0018] The S3 finished product processing steps involve inspecting the concrete components that have reached the design strength after demolding and curing. After passing the inspection, the components are packed on wooden pallets using a packing machine. A 3mm thick bubble wrap is placed between each layer of components for isolation. The stacking height does not exceed 1.5 meters, and the number of stacking layers does not exceed 10. After packing, classification labels are affixed, indicating the type, model, and quantity of the components. Then, a forklift is used to transport the components to a flat and solid storage area for classified and zoned storage.

[0019] This embodiment takes the production of small precast components in the third section of the new construction project of the Xingyang-Xinmi section of the Jiaoping Expressway as an example to explain in detail the implementation process of the technical solution of the present invention. The project needs to produce precast concrete cover plates, rapid flow channels, hexagonal blocks and other components. The designed concrete volume of the precast components is 15,000 cubic meters. The surrounding solid waste materials are mainly solid waste stone powder from the raw material processing of cement plants and mountain stone fragments from stone crushing plants.

[0020] Specifically, a ZL50 loader is used to transport solid waste stone powder (particle size 10-20mm), magnesium chloride, magnesium oxide, citric acid, and stone chips to the raw material silo. The materials are then conveyed to the mixing pot of the 120+90 type concrete mixing plant according to the determined ratio via a crawler conveyor. The dual vertical shaft differential vortex mixing technology is then activated for dry mixing. The dry mixing time is strictly controlled to 30 seconds to ensure that the materials are initially mixed evenly.

[0021] After dry mixing, add tap water according to the mix proportions and continue mixing for at least 60 seconds, maintaining dual-shaft differential vortex mixing during this period, until the magnesium oxychloride cementitious material is fully dissolved, the concrete shows no agglomeration or segregation, and a uniform magnesium oxychloride concrete is formed. During the mixing process, the concrete condition is observed through the batching plant's monitoring system to ensure that the mixing effect meets the requirements.

[0022] After the mixing is completed, the preliminary preparation for the S2 molding step is carried out—mold treatment.

[0023] 920 sets of high-strength plastic molds were selected. The molds were customized according to the type of component, such as hexagonal block molds and cover plate molds. First, the used molds were soaked in a 15-20% diluted oxalic acid solution for 8 minutes (new molds were directly cleaned with a 4% detergent solution) to remove the concrete residue on the surface of the molds. Then, they were rinsed in a 4% detergent solution for 5 minutes, and then rinsed clean in a water tank. After being taken out, they were stacked with the opening facing down to dry, and then transported to the production area.

[0024] Use an electric spray gun to evenly spray the release agent (choose salad oil that meets edible oil standards) onto the dried mold surface and edges. Control the amount of oil during spraying to ensure that the release agent does not drip and forms a uniform film on the surface, thus avoiding contamination of the mold or affecting the appearance of the component.

[0025] Using 15m 3 Concrete mixer trucks transport magnesium oxychloride concrete from the mixing plant to the pouring area. A self-propelled concrete placing boom pours the concrete into the molds, and manual leveling with scrapers ensures the molds are completely filled and the surface is smooth. During pouring, concrete is poured in 50 m³ increments. 3 Three sets of test blocks under the same conditions (corresponding to claim 3) are reserved for the concrete volume. The size of the test blocks is consistent with that of the component and is used for subsequent quality testing.

[0026] After the concrete is poured, the mold containing the concrete is transferred to the frequency-controlled vibrating table. The vibrating table is turned on and the vibration time is controlled at about 90 seconds. During this time, the concrete surface is observed until the air bubbles are completely dissipated and the surface is flat without depressions. Then the vibrating table is turned off.

[0027] Specifically, a 3.5t forklift equipped with roller pallets is used to slowly transport the vibrated molds to the curing area (transfer speed controlled within 5km / h to prevent concrete overflow). The curing area is leveled and compacted in advance. After the molds are stored for 20 minutes, a designated person uses a trowel to smooth the concrete surface and clean any residual mud along the mold walls.

[0028] After the concrete has initially set, it enters the curing stage. The curing is carried out in a cool place without watering. During this period, the ambient temperature is monitored in real time. When the temperature is below 0°C, the mold is covered with an insulating blanket. The curing period lasts for a total of 28 days.

[0029] After curing for 24-48 hours, choose the time of day with the highest temperature and take advantage of the fact that the expansion coefficient of the plastic mold is greater than that of concrete to perform the demolding operation: manually, with the help of a special demolding frame, first turn the component and the mold over and place it on a self-made demolding bracket. Then, use a rubber mallet to gently tap the side wall of the mold around the component, with the force being just enough to slightly deform the mold without damaging it, until the component naturally detaches from the mold. After demolding, immediately cover the component with a curing cloth and continue to moisturize and cure until it reaches the C25 design strength.

[0030] After the components have been cured to their design strength, the supervision unit and the project's quality management department jointly inspect them, checking their appearance (no missing edges or corners, smooth surface), dimensions (deviations conforming to JTG-F80 / 1-2017 standard), and strength (tested using test blocks under the same conditions). Once the inspection is passed, the components proceed to the S3 finished product processing step. Specifically, a palletizer is used to place the qualified components on wooden pallets, with 3mm thick bubble wrap between each layer of components. The stacking height is controlled within 1.5 meters, and the number of layers does not exceed 10 (8 layers for hexagonal block components). Then, a packing machine is used to secure each layer of components to the wooden pallet using packing straps. A classification label is affixed to the side of each bundle, indicating the component type (e.g., "hexagonal block," "slipper"), model (e.g., "600×300×150mm"), and quantity (e.g., "20 pieces / bundle").

[0031] Finally, a 3.5t forklift was used to transport the packaged components to the designated storage area for the project. This area was pre-leveled and compacted, and the components were stored in separate areas according to their type (such as cover plate area and hexagonal block area) to facilitate inventory and delivery during the later stages of project installation.

[0032] Example 2 Building upon Example 1, the process also includes S4 mix proportion optimization, which occurs before S1 mixing. Specifically, according to the mix proportion, a portion of solid waste stone powder or slag is weighed and mixed with magnesium oxychloride cementitious material as test materials. Water is added after mixing the test materials to ensure the cementitious material is fully dissolved, thus forming magnesium oxychloride concrete. Test blocks are then made using this concrete, and the mechanical properties of the test blocks are analyzed and tested through material mechanics testing to adjust and optimize the mix proportion. The mechanical tests assess the dynamic mechanical properties of the material by combining an electromagnetically driven Hopkinson pressure bar (SHPB) device with high-speed imaging technology (DIC), and evaluate the static mechanical properties of the material through static flexural and compressive strength tests.

[0033] Specifically, firstly, according to the project's requirements for component strength (C25 grade), test solid waste stone powder (particle size 10-20mm), magnesium chloride, magnesium oxide, citric acid, stone chips, and other materials are weighed, mixed with water according to the preliminary proportion to form magnesium oxychloride concrete, and multiple sets of test blocks are made.

[0034] An electromagnetically driven Hopkinson bar (SHPB) device and high-speed imaging technology (DIC) were used to conduct dynamic mechanical property tests on the specimens and observe the deformation and failure process of the specimens under impact loads. At the same time, static flexural and compressive strength tests were conducted to record the strength data of the specimens under static stress.

[0035] Specifically, the static mechanical property tests were conducted using a microcomputer-controlled electro-hydraulic servo universal testing machine (model: YNS300) manufactured by China Machinery Testing Equipment Co., Ltd., to perform static flexural and compressive strength tests on standard mortar specimens measuring 40mm×40mm×160mm. The flexural test employed the three-point bending method, and the compressive test followed the loading method specified in GB / T17671-1999. The flexural and compressive strengths of the specimens were recorded.

[0036] Dynamic mechanical performance testing employed an electromagnetically driven Hopkinson pressure bar (SHPB) device and a Photron FASTCAMSA1.1 high-speed camera system (DIC technology) from Japan to conduct dynamic impact tests on a Φ50×25mm specimen. Specifically, as follows... Figure 2As shown, the electromagnetically driven Hopkinson pressure bar (SHPB) device consists of a pressure bar system, a measurement system, a data acquisition and processing system, and a drive system. The pressure bar system includes a frame and an absorption bar 14. An impact bar 11, an incident bar 12, and a transmission bar 13 are coaxially arranged on the frame in sequence. The impact bar 11, incident bar 12, and transmission bar 13 are all slidably connected to the frame. After being accelerated by electromagnetic drive, the impact bar 11 impacts the incident bar 12, generating an incident stress wave in the incident bar 12. The incident bar 12 is used to propagate the incident stress wave to the sample. In this embodiment... In the measurement system, the impact rod 11 is 0.4m long, the incident rod 12 is 2.0m long, and the transmission rod 13 is 1.4m long. The transmission rod 13 is used to receive the transmitted stress wave passing through the sample. The absorption rod 14 is used to absorb the residual stress wave in the transmission rod 13 to prevent reflection interference. The measurement system includes a velocimeter 21 and a dynamic impact strain gauge 22. The velocimeter 21 is used to measure the impact velocity of the impact rod 11. The dynamic impact strain gauge 22 includes a resistance strain gauge attached to the incident rod 12 and the transmission rod 13, and a device connected to the resistance strain gauge for data acquisition and analysis. The system includes a super-dynamic strain gauge that records strain signals from incident, reflected, and transmitted waves; a data acquisition and processing system including a computer 20, which consists of a host and a display screen connected via a data cable, and a digital oscilloscope connected via the same data cable; the digital oscilloscope is used to acquire and store strain signals from the super-dynamic strain gauge; the computer 20 is connected to the digital oscilloscope via a data cable and to the super-dynamic strain gauge for processing and analyzing the waveform signals acquired by the super-dynamic strain gauge, and for inverting and calculating the dynamic mechanical parameters of the material; the drive system is an electromagnetic drive device including an electromagnetic coil 31 and a power control system 30, the electromagnetic coil 31 is used to drive the impact rod 11 to accelerate, and the power control system 30 is used to control the output power of the electromagnetic coil 31, thereby driving the impact rod 11 through electromagnetic force to achieve precise control of the impact speed and stress pulse waveform; the Japanese Photron FASTCAMSA1.1 high-speed camera system (DIC technology) includes a high-speed camera, which is mounted on a frame and can photograph the surface of the sample. The DIC technique is based on the principle that "the gray-level distribution of the image remains unchanged before and after deformation." It selects a small region (sub-region) in the image before deformation as a reference, and then finds the corresponding region in the deformed image with the most similar gray-level distribution to determine the displacement vector (u, v) of the sub-region. The expression for the gray-level correlation function is:

[0037] In the formula, The image grayscale values ​​before deformation. The grayscale values ​​of the deformed image. Let be the displacement vector to be determined. The average gray level of the sub-region before deformation. The average grayscale value of the deformed sub-region The formula for calculating the strain field is: , ,

[0038] In the formula, for Displacement in the direction, for Displacement in the direction, , For normal strain, This represents shear strain.

[0039] The testing process is divided into three stages: device preparation, loading test, and data acquisition and processing. In the device preparation stage, the specimen is placed between the incident rod and the transmission rod, and the position of the impact rod is adjusted to make the impact rod and the absorption rod coaxial. An annealed copper disk (waveform shaper) is installed on the incident rod to eliminate the stress wave dispersion effect and ensure the stability of the stress waveform. Vaseline is applied to the end face of the specimen to reduce the friction between the specimen and the rod and ensure uniform propagation of the stress wave. At the same time, the dynamic strain gauge and the high-speed camera system (such as Photron FASTCAM SA1.1) are calibrated, and the shooting frequency of the high-speed camera is set (10000 Fps in this study) to ensure the accuracy of data acquisition.

[0040] During the loading test phase, the electromagnetic control system is activated, driving the impact rod to strike the incident rod at a set speed via electromagnetic force, generating a stress wave. The stress wave propagates along the incident rod, sequentially triggering the strain gauges on the incident rod (which record the incident wave), the reflection and transmission at the specimen interface, and the strain gauges on the transmission rod (which record the transmitted wave), while the reflected wave is captured a second time by the strain gauges.

[0041] During the data acquisition and processing phase, the dynamic strain gauge collects strain signals from the incident wave, reflected wave, and transmitted wave in real time and transmits them to the computer for storage. Using the "three-wave method" formula, combined with the elastic modulus, density, cross-sectional area, and specimen dimensions of the elastic rod, the dynamic strain rate, dynamic strain, and dynamic stress of the specimen are calculated, generating a stress-strain curve. Combined with high-speed camera image sequences, digital image correlation (DIC) technology is used to analyze the strain field distribution on the specimen surface, assisting in determining the material's failure mode (such as multi-crack failure or through-crack failure).

[0042] Before the experiment, random speckles were artificially prepared on the surface of the specimen (e.g., by spraying black and white paint) to form unique grayscale feature markers, providing "recognition points" for subsequent image matching. A high-speed camera was simultaneously activated at the start of the impact loading, continuously capturing image sequences of the specimen during deformation to ensure that every instantaneous state was recorded, forming a... Figure 3 The image shown, Figure 3In the diagram, a represents multiple crack failure, b represents penetration failure, and c represents localized failure. Using strain contour maps generated by DIC technology combined with stress-strain curves, the deformation and failure characteristics and dynamic damage evolution under different material ratios are analyzed.

[0043] Based on the test results, the mix proportions were adjusted and optimized, and the final mix proportions for each cubic meter of magnesium oxychloride concrete were determined.

[0044] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that the technical means for solving problems in the above embodiments of the present invention can be used in combination to solve multiple technical problems simultaneously. For those skilled in the art, several modifications and improvements can be made without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for utilizing solid waste stone powder or slag based on silicate cement and alkaline oxides, characterized in that: The process includes the following steps: S1 Mixing: Mix solid waste stone powder or stone slag with magnesium oxychloride cementitious material according to the proportion, add water, and mix again to ensure that the cementitious material is fully dissolved to form magnesium oxychloride concrete; S2 Molding: Pour the magnesium oxychloride concrete obtained in S1 into a mold, and demold after the magnesium oxychloride concrete has cured to obtain a concrete component.

2. The method for utilizing solid waste stone powder or slag based on silicate cement and alkaline oxides according to claim 1, characterized in that: In S1 mixing, the mixing equipment adopts vibration mixing technology, and the magnesium oxychloride concrete is mixed by dual vertical shaft differential vortex mixing.

3. The method for utilizing solid waste stone powder or slag based on silicate cement and alkaline oxides according to claim 2, characterized in that: During the pouring of S2, test blocks under the same conditions are reserved according to the concrete volume for subsequent quality testing.

4. The method for utilizing solid waste stone powder or slag based on silicate cement and alkaline oxides according to claim 3, characterized in that: In S1, the magnesium oxychloride cementitious material is composed of magnesium chloride, magnesium oxide and citric acid. The particle size of solid waste stone powder or stone slag is 10-20mm. The mix proportion is calculated per cubic meter of magnesium oxychloride concrete as follows: 164kg magnesium chloride, 266kg magnesium oxide, 3kg citric acid, 1509kg solid waste stone powder or stone slag, 328kg stone chips and 131kg water. The mixing process first involves conveying solid waste stone powder or stone slag, magnesium oxychloride cementitious material and stone chips to the mixing pot via a conveyor belt and dry mixing for 30 seconds. Then, water is added and the mixture is stirred for no less than 60 seconds. The mixing process employs dual vertical shaft differential vortex mixing technology.

5. The method for utilizing solid waste stone powder or slag based on silicate cement and alkaline oxides according to claim 4, characterized in that: In S2, before pouring, the mold is cleaned and sprayed with a release agent. For cleaning, the mold is first soaked in a 15-20% diluted oxalic acid solution for 5-10 minutes, then rinsed in a 4% detergent solution, and finally cleaned and dried in a clean water tank. The release agent is salad oil that meets edible oil standards, applied evenly using an electric spray gun. During pouring, a self-propelled concrete placing machine is used for placement, with manual leveling. After pouring, a frequency-controlled vibrating table is used for compaction, with vibration time controlled at approximately 90 seconds, until all air bubbles in the concrete are completely dissipated and the surface is smooth. The curing process includes curing and maintenance. Curing is carried out in a cool place without watering; when the temperature is below 0°C, insulation measures are taken. The curing period is 28 days. Demolding is carried out 24-48 hours after pouring, on the day with the highest temperature. After demolding, the mold is covered with a curing cloth for continued moisturizing until the design strength is reached.

6. The method for utilizing solid waste stone powder or slag based on silicate cement and alkaline oxides according to claim 1, characterized in that: In S2, demolding is done manually with the help of a special demolding frame. When demolding, the component is first flipped over and placed on a self-made demolding bracket. Then, a rubber hammer is used to tap around the component to make it fall out of the mold naturally.

7. The method for utilizing solid waste stone powder or slag based on silicate cement and alkaline oxides according to claim 6, characterized in that: It also includes the S3 finished product processing step, which involves inspecting the concrete components that have reached the design strength after demolding and curing. After passing the inspection, the components are packed on wooden pallets using a packing machine. Each layer of components is separated by a 3mm thick bubble wrap. The stacking height does not exceed 1.5 meters and the number of stacking layers does not exceed 10. After packing, classification labels are affixed, indicating the type, model, and quantity of the components. Then, forklifts are used to transport the components to a flat and solid storage area for classified and zoned storage.

8. The method for utilizing solid waste stone powder or slag based on silicate cement and alkaline oxides according to claim 1, characterized in that: It also includes S4 mix optimization. Before mixing in S1, according to the mix ratio, a portion of solid waste stone powder or stone slag and magnesium oxychloride cementitious material are weighed as test materials. After mixing the test materials, water is added to ensure that the cementitious material is fully dissolved, thereby forming magnesium oxychloride concrete. Test blocks are made using the concrete, and the mechanical properties of the test blocks are analyzed and tested through material mechanics tests in order to adjust and optimize the mix ratio.

9. The method for utilizing solid waste stone powder or slag based on silicate cement and alkaline oxides according to claim 8, characterized in that: Mechanical tests were conducted to evaluate the dynamic mechanical properties of the materials by combining an electromagnetically driven Hopkinson bar (SHPB) device with high-speed imaging technology (DIC), and to evaluate the static mechanical properties of the materials by static flexural and compressive strength tests.

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