A construction method for cold in-place recycling of highway surface layer

Abstract

The present application relates to the technical field of road engineering, and more particularly to a construction method for cold in-place recycling of highway surface layer, comprising the following steps: firstly, treating the original road surface diseases, grooving and filling the original road surface transverse cracks, then, using a powder spreader to uniformly spread cement on the original road surface according to a certain proportion, milling the original road surface to obtain milling material, designing a component addition ratio scheme according to the milling material gradation of the original road surface, adding the component into the cold recycling machine according to the ratio scheme, and synchronously performing milling operation by the cold recycling machine to obtain a mixture, wherein the milling depth reaches the top surface of the underlying layer, the mixture is discharged onto the milled road surface, and the gradation composition of the mixture is detected, the mixture that does not meet the design requirements is secondarily mixed, the lifting device is used to feed the paver, the paver is operated to form a recycled working surface, the upper layer is laid on the recycled working surface, and the recycled working surface is compacted and cured.

Description

Technical Field

[0001] This invention relates to the field of road engineering technology, and in particular to an in-situ cold recycling construction method for highway surface layers. Background Technology

[0002] With my country's rapid economic development and high-speed growth in traffic volume, the phenomena of heavy-load and overloaded vehicles have become increasingly serious, and various defects in traditional asphalt pavements have become more and more apparent. As of 2017, the total length of highways in China reached 5.2807 million kilometers, including 169,100 kilometers of expressways. The length of highways under maintenance reached 5.2516 million kilometers, accounting for 99.4% of the total highway mileage. my country's highway transportation spends a considerable amount on highway maintenance. The rational utilization of asphalt pavement waste can reduce environmental pollution and the land occupation caused by waste accumulation, and is more conducive to the protection of my country's natural resources.

[0003] However, due to the difficulty in controlling the quality of on-site construction, this patent proposes an on-site cold recycling construction method for highway surface layers in order to reduce the segregation of cold recycled materials in the old material gradation and construction process, improve the stability of the entire construction process, and improve the overall flatness of the on-site cold recycled layer.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the general background of this disclosure and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide an in-situ cold recycling construction method for highway surface layers, which improves the reusability of milled material, ensures stable quality of recycled layer, enables precise control of the gradation of newly laid asphalt mixture, reduces pavement segregation, and improves the overall smoothness and service life of in-situ cold recycled pavement.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is: an in-situ cold recycling construction method for highway surface layers, comprising the following steps:

[0007] S1: Treatment of existing pavement defects, including flaw detection of the existing pavement, excavation and filling of transverse cracks in the existing pavement;

[0008] S2: Use a powder spreader to evenly spread cement on the original road surface according to a certain ratio;

[0009] S3: Mill the original road surface and extract the material, and design the proportion of added components based on the gradation of the milled material from the original road surface.

[0010] S4: According to the formula, add the additive components into the cold recycling machine. The cold recycling machine performs milling operation simultaneously to obtain the mixture, wherein the milling depth reaches the top surface of the lower layer.

[0011] S5: Discharge the mixture onto the milled road surface and test the gradation of the mixture;

[0012] S6: Remix the mixture if it does not meet the design requirements;

[0013] S7: A lifting device is used to feed material into the paver, and the paver performs paving operations to form a recycled working surface, which is then compacted.

[0014] S8: Lay the top layer on the recycling work surface, compact it, and then cure it.

[0015] It should be noted that the in-situ cold recycling construction method provided by this invention first requires surveying the original pavement for defects, including at least damage, potholes, and transverse cracks. Surface damage and potholes do not affect the pavement base layer and therefore require no treatment. However, transverse cracks reaching the base layer, if left untreated, may continue to develop into surface cracks on the newly paved asphalt pavement as the cracks widen. The location of the cracks is determined by pavement flaw detection, and the condition of the cracks is examined through excavation. Cracks in the pavement base layer must at least be repaired. After the defects are treated, the original pavement is milled to extract material. This is mainly to test the gradation of aggregates, asphalt-aggregate ratio, and asphalt aging degree within the original pavement. Therefore, only a section of road needs to be milled as a test pavement, preferably between 30m and 100m, to design the proportioning scheme for added components. When reusing the milled material from the old pavement, the main focus is on the aggregates, while the original road surface... During construction, multiple layers may be involved. For example, a top layer, intermediate layer, and bottom layer may be laid on top of the road base. The two layers have different purposes, so their asphalt-aggregate ratios are also different. During milling, the top layer and intermediate layer need to be milled away simultaneously, down to the top surface of the bottom layer. This is to reduce construction difficulty and to directly mix the multiple layers evenly for easy reuse. According to the procedure, a layer of cement is then spread on the road surface. After the cement is spread, a cold recycling machine is used to mill the road surface, and additives are added to the cold recycling machine at the same time. Currently, most cold recycling machines on the market can perform the above operations to obtain a mixture. In this invention, the gradation of the mixture is tested. For mixtures that do not meet the standards, a certain compensating component is added, and the mixture is mixed again to make the mixture before paving meet the construction requirements. Then, the mixture is improved and paved, compacted, and the top layer is laid. After curing, the construction of the entire road surface is completed. Because the performance of the original milled material is unstable, the top layer is composed of SBS modified asphalt and graded crushed stone. The specific components and proportions can be found in existing technologies. The reason for using new aggregates and SBS modified asphalt for the top layer is that, as the main stress-absorbing layer, the construction quality is easier to control.

[0016] Furthermore, before milling the road surface, the original road surface needs to be cleaned to reduce dust and debris.

[0017] Further, in step S1, the specific method of excavating and filling the transverse cracks in the original road surface is as follows: a trench of a certain width and depth to the top surface of the road base is milled along the direction of the crack extension; the trench below the trench is filled and compacted; basalt fiber cloth is laid on top of the filler and then asphalt mixture is used to fill the trench; the trench is checked for the presence of grooves in the road base by excavating; the grooves are filled; after the filling is completed, small machinery is used for compaction to seal the grooves and reduce the risk of further cracking. In order to further reduce the probability of cracking at the filler, basalt fiber cloth is laid on top of the filler and then asphalt mixture is used to fill the trench. The basalt fiber cloth is made of basalt fiber material, which has high strength, corrosion resistance and can bear load for a long time. When asphalt mixture is laid on top of basalt fiber cloth, it can effectively disperse the pressure of the asphalt mixture above, thereby preventing the continued generation of cracks and the asphalt mixture from sinking into the cracks in the road base.

[0018] Further, in step S3, the added components include emulsified asphalt mixture and water, wherein the emulsified asphalt mixture includes the following components in parts by weight: 105 parts of No. 70 asphalt, 150 parts of epoxy resin, 55 parts of amino-terminated polymethyl hydroquinone ether benzophenone, 10 parts of organosilicon monomer, 25 parts of emulsifier, 23 parts of calcium carbonate whiskers, 20 parts of basalt fiber, 20 parts of mica powder and 50 parts of glass microspheres.

[0019] The emulsified asphalt mixture provided by this invention uses amino-terminated polymethylhydroquinone ether as a macromolecular flexible curing agent. The molecular chain of amino-terminated polymethylhydroquinone ether contains ether and ketone bonds. The presence of ether bonds significantly improves the flexibility of the crosslinking points of the cured product, while the introduction of ketone bonds greatly improves the toughness, high-temperature resistance, and fatigue resistance of epoxy resin during curing. Since the silicon-oxygen bonds in the main chain of organosilicon monomers are very stable, they effectively improve the weather resistance of the cured product. Through the skeletal connection between two or more inorganic silicon-oxygen bonds and organic branches, the chemical bonds in the cured epoxy resin are stronger, resulting in a more stable molecular structure and achieving its chemical properties and excellent temperature resistance. The changes are relatively small, further improving the performance of epoxy resin, improving the structural strength of emulsified asphalt after demulsification and coagulation, increasing the toughness and fatigue resistance of emulsified asphalt, and improving the road performance of emulsified asphalt. The addition of calcium carbonate whiskers and basalt fibers serves two purposes: firstly, to improve the demulsification speed of emulsified asphalt, by having the calcium carbonate whiskers and basalt fibers adhere to the emulsion, thereby increasing the contact area of ​​the emulsion; secondly, after the asphalt binder has cured, the basalt fibers can improve the bonding strength between aggregates and prevent segregation between aggregates. The addition of glass microspheres can increase the fluidity of the emulsified asphalt mixture, making it easier to spray later, and can also be used as a dense filler to fill the interior of the road surface layer.

[0020] Furthermore, the weight ratio of the emulsified asphalt mixture, water, and original road milling material is 5-6.5:2-4:100. This design reference is based on the ratio of aggregate to asphalt binder in the original road milling material. Due to the reduced service life and poor road performance of the original asphalt binder, emulsified asphalt mixture is added again according to an asphalt-aggregate ratio of 5-6.5.

[0021] Furthermore, the preparation method of the emulsified asphalt mixture includes the following steps:

[0022] A1: Add calcium carbonate whiskers, basalt fiber, mica powder and glass microspheres into a stirring device according to the proportion, and stir at room temperature for 3 to 5 minutes to obtain a premix;

[0023] A2: Add amino-terminated polymethyl hydroquinone ether dibenzophenone, organosilicon monomer, and emulsifier to the premix and stir at room temperature for 10-20 minutes to obtain an intermediate mixture;

[0024] A3: Add No. 70 asphalt and epoxy resin to the intermediate mixture and stir at room temperature for 20 minutes to obtain emulsified asphalt mixture.

[0025] This invention improves the performance of emulsified asphalt by optimizing the order of adding each component in the mixture. Specifically, fillers and inorganic materials are first added to a mixing device and stirred at room temperature to achieve uniform dispersion. Then, amino-terminated polymethyl hydroquinone ether, organosilicon monomer, and emulsifier are added to the mixing device and stirred continuously. The addition of amino-terminated polymethyl hydroquinone ether, organosilicon monomer, and emulsifier effectively disperses the emulsifier, allowing it to adhere to calcium carbonate whiskers and basalt fibers, thereby accelerating the demulsification speed of the emulsified asphalt. Furthermore, since they are added before the asphalt, they facilitate flow and dispersion. The addition of No. 70 asphalt and epoxy resin initiates the reaction process of the emulsified asphalt. Before the reaction begins, the additives are thoroughly stirred to ensure uniformity, which facilitates the subsequent emulsification of the asphalt and the curing reaction of the epoxy resin, thus improving the reaction process.

[0026] Furthermore, an auxiliary discharge path is provided at the discharge end of the cold recycling machine. The auxiliary discharge path is used to quantitatively convey the mixture to the vibrating funnel device every 5-10 minutes. The vibrating funnel device is equipped with screens of different screen hole sizes. The size of the screen holes in the screens decreases from top to bottom. Each layer of screens has a discharge port on one side, and a weighing mechanism is provided at the discharge port.

[0027] In this invention, to enable real-time detection of the gradation of milled material, a secondary discharge path is added at the outlet of the cold recycling machine during its forward movement. A portion of the milled material falls into a vibrating funnel device via this secondary discharge path. The vibrating funnel device can be readily purchased using existing technology; here, it only provides the function of vibrating and screening. The vibrating funnel device screens the milled material, with smaller particles falling onto the lower screen and larger particles onto the upper screen. Each screen layer has an outlet on one side, and a weighing mechanism is installed at the outlet. The screened milled material enters the weighing mechanism through the outlet for weighing, thus obtaining the gradation composition of a short distance in real time. According to design requirements, milled material that does not meet the design requirements is remixed and added. The secondary discharge path provided by this invention allows for real-time detection and synchronous operation, eliminating the need for manual screening and reducing errors.

[0028] Furthermore, the weighing mechanism intermittently weighs the materials discharged from different outlets, generates measurement data, and sends it to the monitoring terminal. In order to obtain gradation data more intelligently, the data can be collected through the monitoring terminal, which makes it easier for staff to collect data for the entire road section.

[0029] Furthermore, the monitoring terminal also monitors the amount of powder spreader, the rate at which additives are added into the cold regenerator, and the speed of the cold regenerator. An alarm mechanism is set for data exceeding the threshold. A specific threshold range can be designed by calculation method for the amount of powder spreader, the rate at which additives are added into the cold regenerator, and the speed of the cold regenerator. By comparing the real-time monitoring data with the threshold range, the alarm mechanism is triggered, which is conducive to the control of each step.

[0030] Furthermore, a first baffle and a second baffle are sequentially installed on the main discharge path of the cold recycling machine. The height of the first baffle is 10%-20% higher than the maximum nominal particle size, and the height of the second baffle is 0%-2% higher than the maximum nominal particle size. A collection device is installed on one side of the baffle. In order to prevent oversized aggregates from falling into the milled material, the collection device is installed to collect aggregates that are more than 20% larger than the maximum nominal particle size, thereby preventing segregation problems caused by oversized aggregates in the milled material.

[0031] The beneficial effects of this invention are as follows: In the on-site cold recycling construction method for highway pavement provided by this invention, the original pavement is first inspected for flaws, and the transverse cracks in the original pavement are excavated and filled to prevent the newly paved pavement layer from continuing to crack. Subsequently, according to the mixing ratio, additives are added to the cold recycling machine, and the cold recycling machine simultaneously performs milling operations to obtain a mixture. The milled material is then reused. In order to improve the reuse performance of the milled material and to accurately control the gradation of aggregates in the mixture, the gradation composition of the mixture is detected when the milled material falls from the cold recycling machine, and gradation data is obtained. The mixture that does not meet the design requirements is mixed a second time to reduce the segregation problem of the pavement and improve the overall smoothness and service life of the on-site cold recycled pavement. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a flowchart of an embodiment of the present invention for an in-situ cold recycling construction method for highway surface layers;

[0034] Figure 2 This is a construction schematic diagram of the in-situ cold recycling construction method for highway surface layer in an embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram of the internal connections of the cold regeneration machine in an embodiment of the present invention.

[0036] Reference numerals: 1. Powder spreader; 2. Emulsified asphalt mixture tanker; 3. Water tanker; 4. Cold recycling machine; 5. Elevator; 6. Paver; 7. Roller; 8. Main road discharge path; 9. Auxiliary road discharge path; 10. Vibrating funnel device; 11. Weighing mechanism. Detailed Implementation

[0037] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0038] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0039] 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 invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0040] like Figures 1 to 3 The on-site cold recycling method for highway surface layers shown includes the following steps:

[0041] S1: Treatment of existing pavement defects, including flaw detection of the existing pavement, excavation and filling of transverse cracks in the existing pavement;

[0042] S2: Use a powder spreader to evenly spread cement on the original road surface according to a certain ratio;

[0043] S3: Mill the original road surface and extract the material, and design the proportion of added components based on the gradation of the milled material from the original road surface.

[0044] S4: According to the formula, add the additive components into the cold recycling machine. The cold recycling machine performs milling operation simultaneously to obtain the mixture, wherein the milling depth reaches the top surface of the lower layer.

[0045] S5: Discharge the mixture onto the milled road surface and test the gradation of the mixture;

[0046] S6: Remix the mixture if it does not meet the design requirements;

[0047] S7: A lifting device is used to feed material into the paver, and the paver performs paving operations to form a recycled working surface, which is then compacted.

[0048] S8: Lay the top layer on the recycling work surface, compact it, and then cure it.

[0049] Specifically, the engineering machinery used in this invention includes at least a powder spreader 1, an emulsified asphalt mixing tanker 2, a water tanker 3, a cold recycling machine 4, a hoist 5, a paver 6, and a road roller 7. The engineering machinery is deployed sequentially. First, through measurement and flaw detection, trenches are excavated and transverse cracks in the original road surface are filled. Then, the powder spreader 1 evenly spreads cement on the original road surface according to the component ratio. After spreading, the cold recycling machine 4 mills the road surface to extract material. The emulsified asphalt mixing tanker 2 and the water tanker 3 are connected to the cold recycling machine 4 through pipelines. The cold recycling machine 4 sprays emulsified asphalt mixture and water, simultaneously milling the surface, and discharging the milled material to the rear of the same lane. In addition to the main road discharge path 8, the cold recycling machine 4 also has an auxiliary road discharge path 9 at its discharge end. The auxiliary discharge path 9 is used to quantitatively convey the mixture to the vibrating funnel device 10 every 5-10 minutes. The vibrating funnel device 10 is equipped with screens of different mesh sizes, with the mesh size decreasing from top to bottom. Each layer of screens has a discharge port on one side, and a weighing mechanism 11 is installed at the discharge port. The weighing mechanism 11 weighs in real time and collects gradation data. For the mixture that does not meet the design requirements, secondary mixing is carried out. The standard asphalt-aggregate ratio is set between 6.5% and 7%. The material is supplemented according to the difference between the actual situation and the design standard to meet the design requirements. Then, the lifting device 5 feeds the material into the paver 6. The paver 6 paves the surface to form a recycled working surface, which is then rolled and shaped. The top layer is laid on the recycled working surface, compacted, and then cured to complete the entire paving process.

[0050] More specifically, before milling the road surface, the original road surface needs to be cleaned to reduce the impact of road impurities on the composition of the milling material.

[0051] In step S1, the specific method for excavating and filling the transverse cracks in the original road surface is as follows: milling a trench of a certain width and depth to the top surface of the road base along the direction of the crack extension, filling and compacting the trench located below the trench, laying basalt fiber cloth on top of the filler, and then filling the trench with asphalt mixture.

[0052] The emulsified asphalt mixture mentioned in this invention comprises the following components by weight: 105 parts of No. 70 asphalt, 150 parts of epoxy resin, 55 parts of amino-terminated polymethyl hydroquinone ether benzophenone, 10 parts of organosilicon monomer, 25 parts of emulsifier, 23 parts of calcium carbonate whiskers, 20 parts of basalt fiber, 20 parts of mica powder, and 50 parts of glass microspheres. When added to the original road milling material, the specific addition ratio is 5-6.5:2-4:100 by weight of the emulsified asphalt mixture, water, and original road milling material. The weight of the original road milling material can be calculated based on the construction width, depth, and driving speed of the cold recycling machine 4. Specifically, the principle is to calculate the weight value by real-time calculation of the volume of the original road milling material. The preparation method of the emulsified asphalt mixture includes the following steps:

[0053] A1: Add calcium carbonate whiskers, basalt fiber, mica powder and glass microspheres into a stirring device according to the proportion, and stir at room temperature for 3 to 5 minutes to obtain a premix;

[0054] A2: Add amino-terminated polymethyl hydroquinone ether dibenzophenone, organosilicon monomer, and emulsifier to the premix and stir at room temperature for 10-20 minutes to obtain an intermediate mixture;

[0055] A3: Add No. 70 asphalt and epoxy resin to the intermediate mixture and stir at room temperature for 20 minutes to obtain emulsified asphalt mixture.

[0056] After multiple tests, the inventors found that the emulsified asphalt mixture obtained by the above-mentioned components and preparation method, when applied to the surface layer of in-situ cold recycling road construction, exhibited a Marshall stability above 15.4 kN, a residual stability of 96.60%, and a dynamic stability of 6825 cycles / mm after 5 days of curing. Furthermore, the dry splitting strength at 15℃ was not less than 0.75 MPa, and the freeze-thaw splitting residual strength ratio was above 83.31%, meeting all testing requirements. The recycled layer provided by this invention possesses excellent strength, high-temperature stability, rutting resistance, and stable quality, making it practical.

[0057] To achieve the technical objective of real-time acquisition of milled material gradation, this invention discloses a specific structure. An auxiliary discharge path 9 is provided at the discharge end of the cold recycling machine 4. This auxiliary discharge path 9 is used to quantitatively convey the mixture to a vibrating funnel device 10 every 5-10 minutes. The vibrating funnel device 10 is equipped with screens of different mesh sizes, with the mesh size decreasing from top to bottom. Each layer of screens has a discharge port on one side, and a weighing mechanism 11 is installed at the discharge port. By weighing the sieved aggregate, the gradation of the aggregate is obtained, and the generated measurement data is sent to a monitoring terminal for real-time monitoring by staff. Simultaneously, the monitoring terminal also monitors the amount of powder spreader, the rate at which additives are added to the cold recycling machine, and the travel speed of the cold recycling machine. An alarm mechanism is set up for data exceeding thresholds.

[0058] In order to reduce the amount of oversized aggregate falling into the milled material for reuse, a first baffle and a second baffle are installed sequentially on the main discharge path of the cold recycling machine. The height of the first baffle is 10%-20% higher than the maximum nominal particle size, and the height of the second baffle is 0%-2% higher than the maximum nominal particle size. A collection device is installed on one side of the baffle, and the collection device can be cleaned periodically.

[0059] Those skilled in the art should understand that this invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to this invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for in-situ cold recycling of highway surface layers, characterized in that, Includes the following steps: S1: Treatment of existing pavement defects, including flaw detection of the existing pavement, excavation and filling of transverse cracks in the existing pavement; S2: Use a powder spreader to evenly spread cement on the original road surface according to a certain ratio; S3: Mill the original road surface and extract the material, and design the proportion of added components based on the gradation of the milled material from the original road surface. S4: According to the formula, add the additive components into the cold recycling machine. The cold recycling machine performs milling operation simultaneously to obtain the mixture, wherein the milling depth reaches the top surface of the lower layer. S5: Discharge the mixture onto the milled road surface and test the gradation of the mixture; S6: Remix the mixture if it does not meet the design requirements; S7: A lifting device is used to feed material into the paver, and the paver performs paving operations to form a recycled working surface, which is then compacted. S8: Lay the top layer on the recycling work surface, compact it, and then cure it; In step S3, the added components include emulsified asphalt mixture and water, wherein the emulsified asphalt mixture comprises the following components in parts by weight: 105 parts of No. 70 asphalt, 150 parts of epoxy resin, 55 parts of amino-terminated polymethyl hydroquinone ether benzophenone, 10 parts of organosilicon monomer, 25 parts of emulsifier, 23 parts of calcium carbonate whiskers, 20 parts of basalt fiber, 20 parts of mica powder and 50 parts of glass microspheres. The weight ratio of the emulsified asphalt mixture, water, and original pavement milling material is 5-6.5:2-4:

100. The preparation method of the emulsified asphalt mixture includes the following steps: A1: Add calcium carbonate whiskers, basalt fiber, mica powder and glass microspheres into a stirring device according to the proportion, and stir at room temperature for 3 to 5 minutes to obtain a premix; A2: Add amino-terminated polymethyl hydroquinone ether dibenzophenone, organosilicon monomer, and emulsifier to the premix and stir at room temperature for 10-20 minutes to obtain an intermediate mixture; A3: Add No. 70 asphalt and epoxy resin to the intermediate mixture and stir at room temperature for 20 minutes to obtain emulsified asphalt mixture; An auxiliary discharge path is provided at the discharge end of the cold recycling machine. The auxiliary discharge path is used to quantitatively convey the mixture to the vibrating funnel device every 5-10 minutes. The vibrating funnel device is equipped with screens of different screen hole sizes. The size of the screen holes in the screens decreases from top to bottom. Each layer of screens has a discharge port on one side, and a weighing mechanism is provided at the discharge port.

2. The in-situ cold recycling construction method for highway surface layers according to claim 1, characterized in that, Before milling the road surface, the original road surface must be cleaned.

3. The in-situ cold recycling construction method for highway surface layers according to claim 1, characterized in that, In step S1, the specific method for excavating and filling the transverse cracks in the original road surface is as follows: milling a trench of a certain width and depth to the top surface of the road base along the direction of the crack extension, filling and compacting the trench located below the trench, laying basalt fiber cloth on top of the filler, and then filling the trench with asphalt mixture.

4. The in-situ cold recycling construction method for highway surface layers according to claim 1, characterized in that, The weighing mechanism intermittently weighs the materials discharged from different outlets, generates measurement data, and sends it to the monitoring terminal.

5. The in-situ cold recycling construction method for highway surface layers according to claim 4, characterized in that, The monitoring terminal also monitors the amount of powder spreader, the rate at which additives are added into the cold regenerator, and the speed at which the cold regenerator travels. An alarm mechanism is set up for data exceeding the threshold.

6. The in-situ cold recycling construction method for highway surface layers according to claim 1, characterized in that, A first baffle and a second baffle are sequentially installed on the main discharge path of the cold recycling machine. The height of the first baffle is 10%-20% higher than the maximum nominal particle size, and the height of the second baffle is 0%-2% higher than the maximum nominal particle size. A collection device is installed on one side of the baffle.

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