A durable repair structure for potholes and grooves based on semi-flexible materials and its preparation method

Abstract

The present invention discloses a durable repair structure for potholes based on semi-flexible materials and a preparation method thereof, belonging to the technical field of road engineering materials. The durable repair structure for potholes provided by the present invention includes a crushed stone grouting composite material layer, a normal temperature asphalt crushed stone grouting composite material layer, and a drainage channel; the drainage channel is perpendicular to the ground and penetrates through the crushed stone grouting composite material layer and the normal temperature asphalt crushed stone grouting composite material layer. The above hierarchical design adopted by the present invention can effectively reduce the cost of the repair structure and at the same time effectively achieve the durable repair of potholes; the present invention constructs a drainage channel through a solid steel pipe, greatly improving the construction efficiency and the overall quality of the repair structure; and the preparation method of the repair structure of the present invention is simple and efficient, and it only takes 1 to 2 hours to complete the repair of potholes, and the road can be quickly opened to traffic, significantly improving the road traffic efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of road engineering materials, and in particular to a durable repair structure for water seepage pits based on semi-flexible materials and a preparation method thereof. Background Art

[0002] The information disclosed in the background of the invention is only intended to enhance understanding of the overall background of the invention and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] Asphalt pavements often develop serious road defects, such as large potholes, due to the long-term interaction of multiple factors, including vehicle load, temperature, and humidity. Potholes affect driving comfort and safety, and their further development can lead to other road surface defects, reducing the pavement's fatigue life. Among the many pothole defects, water-sinking potholes are particularly noteworthy. Water-sinking potholes are primarily caused by poor road drainage, allowing rainwater or groundwater to seep into the pavement structure. Under the repeated effects of vehicle loads, this water continuously flows and impacts within the pavement structure, gradually eroding the pavement material and causing a localized weakening of the pavement's structural strength, ultimately forming water-sinking potholes. Water-sinking potholes pose a more serious threat than ordinary potholes. Firstly, the presence of water increases the risk of vehicles skidding when driving over them, significantly increasing the likelihood of traffic accidents. Secondly, water-sinking potholes are larger in size, and the water they generate continuously erodes the surrounding pavement structure, accelerating their expansion and deterioration, further shortening the pavement's service life.

[0004] Traditional methods for repairing potholes in asphalt pavements typically use cold patching for temporary, quick repairs, followed by centralized repairs with hot-mix asphalt. Large-voided mixes are often used for repairing potholes with water seepage. However, large-voided mixes have relatively few contact points between aggregates, resulting in lower overall structural strength and greater susceptibility to fatigue cracking, loosening, and other damage, impacting the pavement's service life. Furthermore, due to the constant presence of water in the potholes, cold patching can lead to binder failure and even washout of the patch material. Hot patching, on the other hand, can cause water evaporation and form voids within the patch, reducing its density and strength, making it prone to loosening and falling apart. Furthermore, some current mortar-based quick-repair materials for asphalt pavements, such as cement-based, emulsified asphalt, and resin-based, often suffer from poor bonding strength, significant shrinkage, low strength, poor deformation coordination with the base material, and an inability to create effective drainage paths. These materials also struggle to effectively repair potholes with water seepage, hindering effective repair results.

[0005] The application of semi-flexible maintenance materials provides a new idea for the maintenance of pitted water puddles. This material is composed of a composite of cement mortar and asphalt mixture, combining the rigidity of cement materials and the flexibility of asphalt materials. To a certain extent, it improves some of the shortcomings of traditional materials, can better adapt to the deformation of the road surface, and has a good initial bonding effect. However, it also has obvious defects. Due to the relatively dense internal structure of the semi-flexible material, when used for the maintenance of pitted water puddles, the water inside cannot be effectively discharged. With the repeated action of vehicle loads, the water pressure generated by the accumulated water in the pothole continuously increases, eventually leading to cracking at the repaired area, greatly reducing the maintenance effect and unable to fundamentally solve the problem of repairing pitted water puddles.

[0006] Therefore, in view of the hazards of the current pitted water puddle diseases on asphalt pavements and the defects of the current commonly used repair methods and materials for pitted water puddles, it is necessary to invent a repair structure with durable repair characteristics, and at the same time, a repair structure and its construction plan with high strength and early strength characteristics. Summary of the Invention

[0007] In view of this, the present invention provides a durable repair structure for pitted water puddles based on semi-flexible materials and its preparation method. The durable repair structure provided by the present invention can achieve durable repair of pitted water puddles, reduce the repair cost of potholes, and extend the road surface performance and service life of the pitted area of the asphalt pavement.

[0008] In the first aspect, the present invention provides a durable repair structure for pitted water puddles based on semi-flexible materials, including a lower middle layer of gravel grouting composite material, an upper layer of normal temperature asphalt gravel grouting composite material, and a drainage channel; the drainage channel is perpendicular to the ground and penetrates through the gravel grouting composite material layer and the normal temperature asphalt gravel grouting composite material layer;

[0009] The normal temperature asphalt gravel grouting composite material layer includes normal temperature asphalt gravel, sulphoaluminate cement, quartz sand, and silica fume.

[0010] In the second aspect, the present invention provides a preparation method for the above-mentioned durable repair structure for pitted water puddles based on semi-flexible materials, including the following steps:

[0011] Fix a solid steel pipe perpendicular to the ground at the bottom of the pitted water puddle, then fill it with basalt gravel, level it, and pour in a quick-setting cement grouting material, and sprinkle water for curing for 20 - 40 minutes to form a gravel grouting composite material layer;

[0012] Then lay normal temperature asphalt gravel on the surface of the gravel grouting composite material layer, level it, pour in a quick-setting cement grouting material, and pull out the solid steel pipe after the quick-setting cement grouting material has finally set to form a drainage channel; sprinkle water for curing for 20 - 40 minutes to form a normal temperature asphalt gravel grouting composite material layer.

[0013] Compared with the prior art, the present invention has achieved the following beneficial effects:

[0014] (1) The present invention adopts a repair material with a two-layer structure. The middle and lower layers are gravel grouting composite material layers, which have a lower cost and high strength. The upper layer is a normal-temperature asphalt gravel grouting composite material layer, whose form is close to that of the original asphalt pavement. The repair effect is beautiful, which can ensure the anti-skid performance required for vehicle driving, and at the same time has the advantages of high performance and high durability. And a drainage channel penetrating the upper, middle and lower layers is provided, which helps drainage and avoids the problem that the internal water accumulation causes the water pressure to increase and the repaired part to crack, effectively extending the service life of the repaired part and having high reliability. This layered design of the present invention can effectively achieve the durable repair of potholes with water, overcome the problem that traditional materials are difficult to adapt to the complex working conditions of potholes with water, and significantly improve the repair effect and the durability of the road surface.

[0015] (2) The present invention cleverly utilizes the accumulated water in the potholes with water to promote the progress of the cement hydration reaction, thereby effectively accelerating the strength development. In addition, the present invention selects solid steel pipes to construct the drainage channel, which not only ensures the convenience of construction operation, but also enables the excess water to be discharged smoothly along the pipe wall during construction; after the construction is completed, the drainage channel formed after pulling out the solid steel pipes can continuously and stably play the drainage role, reducing the later maintenance cost and greatly improving the construction efficiency and the overall quality of the repair structure; the solid steel pipes can be recycled after construction, effectively reducing the overall repair cost and improving the economic benefit.

[0016] (3) The preparation method of the repair structure of the present invention is simple and efficient. It only takes 1 to 2 hours to complete the repair of potholes with water, and the road can be quickly opened to traffic, significantly improving the road traffic efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings forming a part of this specification are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to these drawings.

[0018] Figure 1 is a schematic structural diagram of the durable repair structure of potholes with water according to an embodiment of the present invention;

[0019] Figure 2 is a picture of a core sample taken after 6 months of use of the durable repair structure of potholes with water according to an embodiment of the present invention;

[0020] In the figure, 1, original road surface; 2, gravel grouting composite material layer; 3, normal-temperature asphalt gravel grouting composite material layer. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] It should be noted that the following detailed description is exemplary and is intended to provide further illustration of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention pertains.

[0022] The present invention provides a durable repair structure for potholes based on semi-flexible materials, including a lower-middle layer of gravel grouting composite material, an upper layer of normal-temperature asphalt gravel grouting composite material, and a drainage channel; the drainage channel is perpendicular to the ground and penetrates through the gravel grouting composite material layer and the normal-temperature asphalt gravel grouting composite material layer.

[0023] The normal-temperature asphalt gravel grouting composite material layer includes normal-temperature asphalt gravel, sulphoaluminate cement, quartz sand, and silica fume.

[0024] In the present invention, normal-temperature asphalt gravel is an asphalt mixture that can be mixed, paved, and compacted at normal temperature.

[0025] The durable repair structure for potholes of the present invention adopts a layered design. The lower-middle layer is a gravel grouting composite material layer, which has a lower cost, wide sources of raw materials, and a strength comparable to that of cement stabilized gravel and far exceeding that of asphalt mixtures. It can withstand heavy loads and complex environmental pressures; at the same time, it has good durability, water damage resistance, extreme temperature resistance, is not easily deformed or cracked, and also has good fatigue resistance, which can significantly extend the road life and reduce maintenance costs. The upper layer is a normal-temperature asphalt gravel grouting composite material layer, whose form is close to that of the original asphalt road surface. It not only has a beautiful repair effect but also ensures the anti-skid performance required for vehicle driving; its construction process is simple, and it can be opened to traffic quickly. At the same time, its performance far exceeds that of ordinary asphalt mixtures, has good durability, can significantly extend the road life, and reduce maintenance costs. And the present invention is provided with a drainage channel perpendicular to the ground and penetrating through the upper, middle, and lower layers. This structure helps with drainage and avoids the problem that the increased water pressure caused by water accumulation inside the pothole leads to cracking at the repair site, effectively extending the service life of the repair site and having high reliability. This layered design of the present invention can effectively achieve the durable repair of potholes, overcome the problem that traditional materials are difficult to adapt to the complex working conditions of potholes, and significantly improve the repair effect and the durability of the road surface.

[0026] In the present invention, when the depth of the pothole is more than 6 cm, the thickness of the normal-temperature asphalt gravel grouting composite material layer is 3.8 - 4.2 cm, and the thickness of the gravel grouting composite material layer is more than 2 cm. The durable repair structure for potholes of the present invention is more preferably for potholes with a depth of 10 - 18 cm, the thickness of the normal-temperature asphalt gravel grouting composite material layer is 3.8 - 4.2 cm, and the thickness of the gravel grouting composite material layer is 6 - 14 cm. For potholes with a depth less than 6 cm, only the normal-temperature asphalt gravel grouting composite material layer can be set.

[0027] In the present invention, the diameter of the drainage channel is 3 - 5 mm. This diameter range can establish an efficient transmission path for water flow, ensuring a smooth flow rate of water in the channel. Even in extreme weather conditions such as heavy rainfall, it can quickly drain the road surface water, prevent the formation of a water film on the road surface, reduce the risk of hydroplaning when vehicles are driving, and ensure driving safety. In addition, this diameter range can effectively block common road debris, such as leaves and small stones, from entering the drainage channel, prevent blockage caused by debris accumulation, ensure the continuous and stable operation of the drainage system, and provide a solid guarantee for the long-term good operation of the road. At least one drainage channel is provided, and the number of drainage channels is adjusted according to the area of the pothole. When multiple drainage channels are provided, the distance between adjacent drainage channels is more than 10 cm.

[0028] In the present invention, the crushed stone grouting composite layer includes basalt crushed stone, sulfoaluminate cement, quartz sand, and silica fume; the particle size of the basalt crushed stone is 16 - 37.5 mm, more preferably 25 - 35 mm. This particle size of crushed stone is easier to spread and level during construction. Because of its larger size, the single-laying coverage area is relatively wider, which can reduce the laying times, thus greatly improving the construction efficiency and shortening the project cycle. This particle size of crushed stone is not prone to excessive particle movement and accumulation during the grouting process and has a relatively high compressive strength, which is beneficial to ensuring the uniformity and stability of the grout body and the overall bearing capacity. Using large particle size crushed stone can reduce the amount of crushed stone used because the surface area of the same volume of large particle size crushed stone is smaller than that of small particle size crushed stone, and the required amount of slurry wrapping is relatively less, thereby reducing the material cost. In addition, the mining and processing of large particle size crushed stone are relatively simple and the cost is relatively low, which can save the project cost to a certain extent. In the crushed stone grouting composite layer, the volume fraction of basalt crushed stone is 70 - 80%.

[0029] In the present invention, the warm mix asphalt macadam is a large void emulsified asphalt cold mix mixture with a void ratio of 20 - 25%. The gradation of the warm mix asphalt macadam meets the following gradation range: the passing rate of the 26.5 mm sieve hole is 100%; the passing rate range of the 19 mm sieve hole is 95 - 100%; the passing rate range of the 16 mm sieve hole is 50 - 100%; the passing rate range of the 13.2 mm sieve hole is 30 - 90%; the passing rate range of the 0.6 mm sieve hole is 1 - 15%; the passing rate range of the 0.075 mm sieve hole is 0 - 5%.

[0030] In the present invention, in the warm mix asphalt macadam grouting composite layer, the volume fraction of the warm mix asphalt macadam is 70 - 80%.

[0031] The present invention also provides a preparation method for the above-mentioned durable pothole repair structure based on semi-flexible materials, including the following steps:

[0032] Fix the solid steel pipe vertically to the ground at the bottom of the water gushing pit, then fill it with basalt gravel, level it, pour in fast-setting cement grouting material, sprinkle water and cure for 20-40 minutes to form a gravel grouting composite material layer;

[0033] Then, normal temperature asphalt macadam is laid on the surface of the macadam grouting composite material layer, and after leveling, fast setting cement grouting is poured in. After the fast setting cement grouting material is finally set, the solid steel pipe is pulled out to form a drainage channel; water is sprinkled and cured for 20 to 40 minutes to form a normal temperature asphalt macadam grouting composite material layer.

[0034] During the preparation process of the repair structure of the present invention, after pouring the fast-setting cement grouting material, the excess grouting material on the surface of the room-temperature asphalt gravel must be cleaned and then cured to expose the room-temperature asphalt gravel and present an uneven surface, so as to prevent the grouting material from remaining on the surface and reducing the anti-skid performance of the road surface.

[0035] In the present invention, the length of the solid steel pipe is at least twice the depth of the water-emerging pit to facilitate its removal after construction. The diameter of the solid steel pipe is 3-5 mm, which is the same as the diameter of the drainage channel, making it less susceptible to clogging. At least one solid steel pipe is provided. In the present invention, the solid steel pipe is preferably placed in the water-emerging area of the water-emerging pit.

[0036] In the present invention, the rapid-setting cement grouting material comprises the following components by mass fraction: 62-69% sulfoaluminate cement, 2-5% quartz sand, 0.6-2% silica fume, 0.2-0.6% water reducer, 0.2-0.6% defoamer, and 26-33% water. The present invention imposes no particular limitation on the preparation method of the rapid-setting cement grouting material; commonly used preparation methods in the art may be employed.

[0037] In the present invention, the final setting time of the sulphoaluminate cement is within 30 minutes, more preferably controlled within 15 minutes, to improve construction efficiency; the particle size of the quartz sand is 80-150 mesh; the water reducer is a polycarboxylic acid-based water reducer; and the defoamer is an inorganic silicon defoamer.

[0038] In the present invention, the rapid setting cement grouting material of the normal temperature asphalt macadam grouting composite material layer further comprises a colorant in an amount of 0.5-1.5% of the mass of sulphoaluminate cement, which is used to adjust the color of the surface layer to keep it as consistent as possible with the road surface color.

[0039] Since fast-setting cement grouting materials require water for curing, the preparation method of the present invention cleverly utilizes the accumulated water in the water pit, which can greatly promote the cement hydration reaction and effectively accelerate the development of strength. In terms of auxiliary construction materials, solid steel pipes are selected to ensure the convenience of construction operations and allow excess water to be smoothly discharged along the pipe wall during construction. The drainage channel formed after the solid steel pipe is pulled out can continuously and stably perform its drainage function. Due to its reasonable pipe diameter design, it is not prone to clogging, effectively reducing the difficulty of construction and the cost of subsequent maintenance, greatly improving construction efficiency and the overall quality of the repaired structure.

[0040] Furthermore, the preparation method of the present invention has excellent adaptability and can easily handle irregular potholes, eliminating the need to expend significant time, expense, and manpower on digging, filling, and leveling the potholes, simplifying the construction process. Furthermore, the color can be precisely adjusted based on the surrounding road surface color, so that the repaired potholes are consistent with the original road surface color. At the same time, a surface texture similar to that of the surrounding road surface can be created, achieving an aesthetically pleasing and seamless repair effect. The entire construction process is simple and efficient, requiring only 1 to 2 hours to complete the construction of a durable repair structure for water-seeping potholes. The road can then be quickly opened to traffic, significantly improving road traffic efficiency.

[0041] The technical solution of the present invention is further described below with reference to specific embodiments.

[0042] Example

[0043] In this embodiment, the depth of the water gushing pit is 14 cm, and the pit area is 3.7×3.2 m 2 , there are water-seeping areas in the downhill section.

[0044] In this embodiment, the particle size of the quartz sand is 100 mesh; the water reducer is PC100 polycarboxylic acid high-efficiency water reducer, and the defoamer is XP-1 inorganic silicone defoamer; the diameter of the solid steel pipe is 4 mm and the length is 30 cm; the final setting time of the sulphoaluminate cement is 15 min; and the average particle size of the basalt gravel is 32 cm.

[0045] This embodiment provides a durable repair structure for water seepage pits based on semi-flexible materials, the structural diagram of which is shown in FIG. Figure 1 As shown, the structure comprises a lower middle layer of a crushed stone grouting composite material, an upper layer of a normal-temperature asphalt crushed stone grouting composite material, and a drainage channel. The drainage channel runs perpendicular to the ground and penetrates both the crushed stone grouting composite material layer and the normal-temperature asphalt crushed stone grouting composite material layer. The crushed stone grouting composite material layer is made of basalt crushed stone and fast-setting cement grouting material, while the normal-temperature asphalt crushed stone grouting composite material layer is made of normal-temperature asphalt crushed stone and fast-setting cement grouting material.

[0046] The fast-setting cement grouting material of the crushed stone grouting composite material layer includes the following components by mass fraction: 63% sulphoaluminate cement, 3.4% quartz sand, 1% silica fume, 0.3% water reducer, 0.3% defoamer, and 32% water.

[0047] The rapid setting cement grouting material of the normal temperature asphalt macadam grouting composite material layer includes the following components by mass fraction: 63% sulphoaluminate cement, 3.4% quartz sand, 1% silica fume, 0.3% water reducer, 0.3% defoamer, 0.7% water-based carbon black pigment, and 31.3% water.

[0048] Normal temperature asphalt macadam is a large-void emulsified asphalt cold mix with a void ratio of 25%. The emulsified asphalt used is 70# cationic emulsified asphalt with a solid content of 65%. The mixture gradation is shown in Table 1.

[0049] Table 1 Grading of large-void emulsified asphalt cold mix

[0050]

[0051] The specific preparation method comprises the following steps:

[0052] 1. Fixing of solid steel pipe:

[0053] After cleaning the bottom of the excavated pit, spray water to moisten the surface. Ensure the excavated pit surface is clean and moist for easier grouting. Place a row of solid steel pipes at the water-seeping area on the downslope of the excavated pit, with a spacing of approximately 10 cm between them. Place 32mm basalt gravel around the pipes, ensuring they are perpendicular to the ground.

[0054] 2. Preparation of crushed stone grouting composite material layer:

[0055] (1) Use water to flush away the loose soil on the surface of the basalt gravel, moisten it and fill it into the pit until it is 4 cm away from the road surface. The top should be flush with the surrounding original base layer. Simply level it so that there are no large cavities between the gravel. No compaction is required.

[0056] (2) Stir sulphoaluminate cement, quartz sand, silica fume, water reducer and defoamer thoroughly and evenly, stir with a stirrer for about 60 seconds at a speed of 1000 rpm to obtain a solid mixture; add water to the solid mixture and stir for about 180 seconds at a speed of 1000 rpm to form a fast-setting cement grouting material with good fluidity.

[0057] (3) Pour the fast-setting cement grouting material with good fluidity on the basalt gravel in step (1). Be careful not to disperse the paved gravel during grouting. First, grout the edge of the pit to ensure that it is bonded with the original base layer, and then fill the entire pit. The pit is full when the grouting material cannot penetrate from the surface. If there is liquid accumulation in the grouting material, use a brush to drag the excess mortar to the grouting area.

[0058] (4) Before the initial hardening of the cement, wipe off the excess grouting material on the surface until the grouting material is flush with the surface of the gravel layer, and cure for 30 minutes. The quick-setting cement grouting material hardens, and the gravel grouting composite layer is obtained. The volume ratio of basalt gravel in this layer is about 78%.

[0059] 3. Preparation of the normal-temperature asphalt gravel grouting composite layer:

[0060] (1) Fill the normal-temperature asphalt gravel above the gravel grouting composite layer in the pit. When filling the normal-temperature asphalt gravel, ensure that the solid steel pipe is perpendicular to the ground. When leveling, use an iron rammer to tamp around the solid steel pipe, and use a small roller or a plate compactor to level the normal-temperature asphalt gravel in other parts.

[0061] (2) Thoroughly stir the sulfoaluminate cement, quartz sand, silica fume, water reducer, defoamer, and water-based carbon black pigment evenly with a stirrer for about 60 seconds at a speed of 1000 rpm to obtain a solid mixture; add water to the solid mixture and stir for about 180 seconds at a speed of 1000 rpm to form a quick-setting cement grouting material with good fluidity.

[0062] (3) Pour the quick-setting cement grouting material with good fluidity onto the normal-temperature asphalt gravel in step (1), and pay attention not to disperse the laid gravel during grouting. First, pour it into the edge of the dug pit to ensure the combination with the original base layer, and then fill the entire pit. When the grouting material cannot penetrate from the surface, it is considered full. After the grouting material is completely poured, the residual quick-setting cement grouting material on the surface of the normal-temperature asphalt gravel needs to be removed to expose the uneven surface of the normal-temperature asphalt gravel, preventing the grouting material from remaining on the surface and reducing the anti-skid performance of the road surface. The volume ratio of the normal-temperature asphalt gravel in the obtained normal-temperature asphalt gravel grouting composite layer is about 78%.

[0063] (4) When the quick-setting cement grouting material finally sets, pull out the solid steel pipe to form a drainage channel, and sprinkle water for curing for 30 minutes. During the curing period, strictly close the traffic, prohibit all personnel and vehicles from passing, and pay attention to preventing rainwater erosion. After the curing is completed, the traffic can be opened.

[0064] This embodiment can complete the construction within 1 hour. The surface texture and color of the repaired position are similar to those of the original road surface, and the repair is fast and beautiful. After the repair, the accumulated water in the pit can be smoothly discharged through the reserved holes, avoiding secondary damage caused by accumulated water. After 6 months of follow-up monitoring, it is found that the repaired area is in good shape, no diseases have occurred, and it has good bearing capacity, fully meeting the use requirements of the road. Figure 2This is a core sample taken after 6 months of using the repair structure of this embodiment. In the figure, 1 is the original road surface, 2 is the gravel grouting composite material layer, and 3 is the normal temperature asphalt gravel grouting composite material layer. It can be seen that the repaired position is firmly bonded to the original road surface structure, achieving a good durable repair effect, fully demonstrating that the repair structure has excellent durability.

[0065] Comparative example

[0066] In this comparative example, traditional asphalt mixture was used to repair the potholes with water pooling. The depth of the potholes with water pooling was 10 cm, and the area of the potholes was 1×1.2 m. 2 . The traditional asphalt mixture was SMA-13 hot patch asphalt mixture.

[0067] As shown in Table 2, through on-site verification, it was found that under the same conditions, after one year of traffic, the rut depth of the road surface at the repair structure of the embodiment was 1 / 10 of that at the repair structure of the traditional asphalt mixture. The number of years required to reach the standard rut depth of 10 mm for high-grade highways specified in the "Technical Specification for Highway Asphalt Pavement Maintenance" (JTG 5142 - 2019) was extended by 420% compared with the traditional asphalt mixture, indicating that the repair structure of the embodiment of the present invention has good durability.

[0068] Table 2 Measured and predicted rut depths of the repair structures of the embodiment and the comparative example after traffic

[0069]

[0070] Test example

[0071] Double-layer structure material specimens prepared by using the same formula and method as those of the embodiment of the present invention, and normal temperature asphalt gravel grouting composite material specimens with the same thickness as the double-layer structure material specimens were compared with ordinary semi-flexible materials (prepared by using P.O42.5 portland cement grouting material and ordinary cold patch material with a void ratio of 25% at a volume ratio of 20:80), SMA-13 asphalt mixture (purchased from Jiaxing Xinshanhe Building Materials Technology Co., Ltd.), and ordinary cold patch material with a void of 25% (purchased from Shanghai Liji Technology Co., Ltd.) in terms of performance. The test results are summarized in Table 3.

[0072] Table 3 Performance comparison between the normal temperature asphalt gravel grouting composite material of the embodiment and other traditional materials

[0073]

[0074] As can be seen from Table 3, compared with ordinary semi-flexible materials, the composite materials of the embodiments of the present invention show more prominent advantages in performance indicators such as high temperature, low temperature and water stability, and the data of each index increase by 5-230%. Compared with the traditional repair materials commonly used for potholes, such as large-void hot-mix and cold-mix asphalt mixtures, the performance advantages of the normal-temperature asphalt macadam grouting composite materials of the embodiments of the present invention are more obvious, and all-round surpassing has been achieved in all performance dimensions, fundamentally breaking through the limitations of traditional materials in terms of performance, and providing a more reliable and efficient material selection scheme for pothole repair projects.

[0075] It is particularly worth mentioning that when the materials of the embodiments of the present invention are subjected to the dynamic stability test at a high temperature of 70 °C under more severe environmental conditions, the overall high-temperature stability performance shown far exceeds that of traditional asphalt mixtures and similar materials; the increase in its dynamic stability compared with other materials reaches 163-1314%. This data fully shows that the technical solution of the embodiments of the present invention has extremely high applicability and reliability in the laying of water-emerging sections under extreme high-temperature environments and heavy traffic.

[0076] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A durable repair structure for potholes based on semi-flexible materials, characterized in that, It includes the lower layer of the crushed stone grouting composite material layer, the upper layer of the normal temperature asphalt crushed stone grouting composite material layer, and the drainage channel; the drainage channel is perpendicular to the ground and penetrates through the crushed stone grouting composite material layer and the normal temperature asphalt crushed stone grouting composite material layer; the normal temperature asphalt crushed stone grouting composite material layer includes normal temperature asphalt crushed stone, sulfoaluminate cement, quartz sand, and silica fume; the diameter of the drainage channel is 3 - 5 mm; at least one drainage channel is provided; the thickness of the normal temperature asphalt crushed stone grouting composite material layer is 3.8 - 4.2 cm, and the thickness of the crushed stone grouting composite material layer is 6 - 14 cm; The preparation method of the pothole durable repair structure based on semi - flexible materials includes the following steps: Vertically fix a solid steel pipe on the water - gushing part at the bottom of the pothole, then fill it with basalt crushed stone, level it and pour in the quick - setting cement grouting material, and sprinkle water for curing for 20 - 40 min to form a crushed stone grouting composite material layer; Then lay normal temperature asphalt crushed stone on the surface of the crushed stone grouting composite material layer, level it and pour in the quick - setting cement grouting material. After the quick - setting cement grouting material finally sets, pull out the solid steel pipe to form a drainage channel; sprinkle water for curing for 20 - 40 min to form a normal temperature asphalt crushed stone grouting composite material layer; the diameter of the solid steel pipe is 3 - 5 mm; at least one solid steel pipe is provided.

2. The durable repair structure for potholes based on semi-flexible materials according to claim 1, characterized in that, The crushed stone grouting composite material layer includes basalt crushed stone, sulfoaluminate cement, quartz sand, and silica fume; the particle size of the basalt crushed stone is 16 - 37.5 mm; in the crushed stone grouting composite material layer, the volume fraction of basalt crushed stone is 70 - 80%.

3. The durable repair structure for potholes based on semi-flexible materials according to claim 1, characterized in that, The normal temperature asphalt crushed stone is a large - void emulsified asphalt cold - mix mixture with a void ratio of 20 - 25%; the grading of the normal temperature asphalt crushed stone meets the following grading range: the passing rate of the 26.5 mm sieve hole is 100%; the passing rate range of the 19 mm sieve hole is 95 - 100%; the passing rate range of the 16 mm sieve hole is 50 - 100%; the passing rate range of the 13.2 mm sieve hole is 30 - 90%; the passing rate range of the 0.6 mm sieve hole is 1 - 15%; the passing rate range of the 0.075 mm sieve hole is 0 - 5%.

4. The durable repair structure for potholes based on semi-flexible materials according to claim 1, characterized in that, In the normal temperature asphalt crushed stone grouting composite material layer, the volume fraction of normal temperature asphalt crushed stone is 70 - 80%.

5. The preparation method of the durable repair structure for potholes based on semi-flexible materials according to any one of claims 1 to 4, characterized in that, It includes the following steps: Vertically fix a solid steel pipe on the bottom of the pothole, then fill it with basalt crushed stone, level it and pour in the quick - setting cement grouting material, and sprinkle water for curing for 20 - 40 min to form a crushed stone grouting composite material layer; Then lay normal temperature asphalt crushed stone on the surface of the crushed stone grouting composite material layer, level it and pour in the quick - setting cement grouting material. After the quick - setting cement grouting material finally sets, pull out the solid steel pipe to form a drainage channel; sprinkle water for curing for 20 - 40 min to form a normal temperature asphalt crushed stone grouting composite material layer.

6. The preparation method according to claim 5, characterized in that, The length of the solid steel pipe is more than twice the depth of the pothole.

7. The preparation method according to claim 5, characterized in that, The quick - setting cement grouting material includes the following components by mass fraction: 62 - 69% sulfoaluminate cement, 2 - 5% quartz sand, 0.6 - 2% silica fume, 0.2 - 0.6% water - reducing agent, 0.2 - 0.6% defoaming agent, and 26 - 33% water.

8. The preparation method according to claim 7, characterized in that, The final setting time of the sulfoaluminate cement is within 30 minutes; the particle size of the quartz sand is 80 - 150 mesh; the water reducing agent is a polycarboxylate water reducing agent; the defoaming agent is an inorganic silicon defoaming agent; the quick-setting cement grout in the normal temperature asphalt macadam grouting composite layer further includes a colorant accounting for 0.5 - 1.5% of the mass of the sulfoaluminate cement.

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