Road structure layer coring test hole filling material and method

Abstract

The invention discloses a road structure layer coring and hole testing filling material and method, the filling material is composed of a composite special cement-based material, a composite nano modified material, aggregate, rubber particles, LDPE particles and a functional additive, and nanoscale super-tough cementing material concrete is formed. The preparation method comprises the following steps: calcining and synthesizing the special cement-based material, preparing the nano modified material by a sol-gel method, and mixing the components according to a specific ratio. The filling method comprises the standardized processes of test hole cleaning, emulsified asphalt interface treatment, material quantitative mixing, layered pouring, inserting and tamping, mechanical tamping and the like. The filling material disclosed by the invention has the characteristics of early strength, rapid hardening, high toughness and complete water resistance, and the filling compactness can reach 98% or above through a spiral inserting and tamping process and special tamping equipment. According to the technology, the technical problems that a traditional filling material is prone to cracking and water seepage are solved, the service life of a filled part is prolonged to 8-10 years, the construction efficiency is greatly improved, and the maintenance cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of pavement engineering, and particularly to a filling material and method for coring test holes in road structural layers. Background Art

[0002] In the current highway engineering quality management system, the quality inspection of pavement structural layers mainly adopts destructive methods such as coring inspection to evaluate key indicators such as thickness and density. However, the existing technologies have the following prominent problems:

[0003] 1. Defects in filling materials:

[0004] a. The strength development of traditional filling materials (such as ordinary asphalt mixtures) is slow, and it is impossible to achieve immediate opening to traffic;

[0005] b. The interface stress concentration is caused by the mismatch of the elastic modulus of the materials;

[0006] c. Lack of effective waterproof design, and moisture is easy to penetrate along the interface.

[0007] 2. Insufficient construction technology:

[0008] a. Lack of standardized test hole cleaning specifications, and it is difficult to ensure the interface bonding quality;

[0009] b. The material ratio control is inaccurate, and the on-site mixing quality fluctuates greatly;

[0010] c. The compaction process is rough and mainly relies on manual experience;

[0011] 3. Long-term performance problems:

[0012] a. Differential settlement is likely to occur in the filling area, forming a "patch effect";

[0013] b. Diseases such as peeling and pumping slurry appear after freeze-thaw cycles;

[0014] c. The average service life is less than 3 years, and the maintenance frequency is high;

[0015] The above technical defects lead to the damage of the integrity of the pavement structure after coring inspection. According to statistics, about 65% of the early pavement diseases originate from improper filling of test holes. Especially in areas with heavy traffic and rainy weather, such problems are more prominent, not only increasing the maintenance cost, but also seriously affecting driving safety.

[0016] Therefore, there is an urgent need in the industry for a systematic solution that can achieve the coordinated matching of material properties with the original road surface, standardize and quantify the construction process, and ensure stable performance throughout the life cycle. In response to this technical gap, the present invention provides reliable supporting technical support for highway quality inspection through innovative material systems and construction methods, and provides alternative and highly operable filling materials and methods for the operators filling test holes, so as to further standardize the test hole filling operation, ensure reliable quality after test hole filling, improve the overall performance of the road surface structure layer, and thus extend the service life of the road surface. Summary of the Invention

[0017] The purpose of this section is to outline some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of the present application, to avoid obscuring the purpose of this section, the abstract, and the title, but such simplifications or omissions shall not be used to limit the scope of the present invention.

[0018] Therefore, to solve the above technical problems, the present invention provides the following technical solution: a filling material for core drilling test holes in a road structure layer, wherein the test hole filling material is nano-scale super-tough cementitious material concrete, comprising a composite special cementitious material, a composite nano-modified material, aggregates, yellow sand, rubber particles, LDPE particles, water, an early strength agent, a composite water repellent, a highly efficient composite water reducer, a thixotropic lubricant, and an expansion agent. The nano-scale super-tough cementitious material concrete is a mixture prepared by mixing the above-mentioned multiple components in a certain proportion;

[0019] The specific components of the filling material are as follows:

[0020] Composite special cementitious material: 45 - 60%;

[0021] Composite nano-modified material: 1.2 - 5.5% (by mass of cement);

[0022] Continuously graded crushed stone (4.75 - 19 mm): 25 - 35%;

[0023] Medium sand (fineness modulus 2.3 - 3.0): 20 - 30%;

[0024] Rubber particles (20 - 60 mesh): 2 - 15% (by mass of cement);

[0025] LDPE particles (60 - 120 μm): 1 - 10% (by mass of cement);

[0026] Composite water repellent: 0.5 - 1.0% (by mass of cement);

[0027] Highly efficient composite water reducer: 0.02 - 0.3% (by mass of cement);

[0028] Thixotropic lubricant: 0.6 - 1.2% (by mass of cement);

[0029] Micro-expansive agent: 0.03 - 0.5% (by mass of cement);

[0030] Water-cement ratio: 0.36 - 0.48;

[0031] As a preferred embodiment of the core sampling test hole filling material for the road structure layer of the present invention, wherein: the composite special cement-based material is calcined at 1500 °C from the following components:

[0032] Tricalcium silicate / calcium oxide (0.5:1.5) 45 - 60%;

[0033] Dicalcium silicate / silicon oxide (0.5:1.5) 20 - 37%;

[0034] Tricalcium aluminate / aluminum oxide (0.5:1.5) 5 - 15%;

[0035] Tetracalcium aluminoferrite / iron oxide (0.5:1.5) 10 - 18%.

[0036] As a preferred embodiment of the core sampling test hole filling material for the road structure layer of the present invention, wherein: the nano-scale super-tough cementitious material concrete is a composite material obtained by mixing and stirring a composite special cement-based material, a composite nano-modified material, sand, stone, a composite water repellent, a highly efficient composite water reducer, an early strength agent, a thixotropic lubricant, a micro-expansive agent, waste LDPE particles, rubber particles and water in a specific proportion.

[0037] As a preferred embodiment of the core sampling test hole filling material for the road structure layer of the present invention, wherein: the composite nano-modified material is a 1:1 composite of porous silicon and amphiphilic nano-silica treated by the sol-gel method. After the sol-gel method treatment, it is decomposed into nano-sized particles with a particle size of 50 - 100 nm by mechanical force.

[0038] As a preferred embodiment of the core sampling test hole filling material for the road structure layer of the present invention, wherein: the concrete gravel uses continuously graded gravel with a nominal particle size of 19 mm to 4.75 mm, and can be composed of two or more specifications of gravel mixed in proportion, mainly acting as the skeleton of the concrete mixture to improve the strength and durability of the concrete.

[0039] As a preferred embodiment of the core sampling test hole filling material for the road structure layer of the present invention, wherein: the yellow sand for concrete uses medium sand with a fineness modulus of 2.3 - 3.0.

[0040] As a preferred solution for the core drilling hole filling material of the road structure layer described in the present invention, among which: the composite water repellent is an organosilicon-fat composite system. Through the carrier and slow release technology, the active ingredient is released in a timely manner when encountering water. In the alkaline environment after the hydration of cement, high-active groups are formed through hydrolysis, and irreversible chemical reactions occur with the hydroxyl groups in the cement hydration products to form a cross-linked structure, endowing the pore surface with water repellency.

[0041] As a preferred solution for the core drilling hole filling material of the road structure layer described in the present invention, among which: the water reducing agent is synthesized by sulfonation reaction of naphthalene sulfonate formaldehyde condensate and superplasticizer, and the water reducing effect is achieved by generating steric hindrance effect.

[0042] As a preferred solution for the core drilling hole filling material of the road structure layer described in the present invention, among which: the filling material mainly selects magnesium aluminum silicate suspension thixotropic thickener to effectively improve the fluidity and lubricity of concrete.

[0043] As a preferred solution for the core drilling hole filling material of the road structure layer described in the present invention, among which: the micro-expansion agent is composed of 80 - 85% natural anhydrous gypsum, 10% natural alunite and 5 - 10% calcined coal gangue. Its main function is to make the cement concrete expand moderately to reduce the volume shrinkage of the concrete, fully fill the gap between the asphalt concrete and the cement concrete, and play a role in densification and water tightness.

[0044] As a preferred solution for the core drilling hole filling material of the road structure layer described in the present invention, among which: the thixotropic lubricant mainly uses magnesium aluminum silicate suspension thixotropic thickener.

[0045] As a preferred solution for the core drilling hole filling material of the road structure layer described in the present invention, among which: the waste polymer material uses waste high-pressure low-density polyethylene (LDPE) after recycling and processing, and the particle size is controlled within 60μm - 120μm.

[0046] As a preferred solution for the core drilling hole filling material of the road structure layer described in the present invention, among which: the waste rubber particles are made from waste rubber tires, and their particle size is 20 - 60 mesh.

[0047] As a preferred solution for the core drilling hole filling material of the road structure layer described in the present invention, among which: the water used for concrete is human and livestock drinking water.

[0048] The present invention also discloses the filling method of the above-mentioned core drilling hole filling material of the road structure layer, which is specifically as follows:

[0049] S1: Hole cleaning and pretreatment;

[0050] Free water removal: Use a highly absorbent sponge or a special absorbent towel to thoroughly absorb the free water accumulated in the hole.

[0051] Debris cleaning: Use a special cleaning spoon and clamp to remove loose particles and residues in the test hole; promptly put the cleaned debris into a collecting tray or a sealed bag to avoid polluting the surrounding road surface;

[0052] Hole wall cleaning: Rinse the inner wall of the test hole with clean water of moderate pressure; suck out the accumulated water after rinsing again; finally wipe the hole wall and the bottom with a clean dry cloth until it is dry;

[0053] S2: Interface bonding layer treatment;

[0054] Emulsified asphalt coating: Select a quick-setting emulsified asphalt with a solid content of ≥ 50%; control the dosage within the range of 100 - 180 mL / test hole; use a special brush to evenly apply the emulsified asphalt on the entire surface of the hole wall;

[0055] Coating quality control: Ensure that the coating thickness is uniform; keep the edge of the hole clean to avoid asphalt overflow and polluting the road surface;

[0056] S3: Preparation of filling materials

[0057] Dry material preparation: Select a pre-prepared material package according to the size of the test hole. Specifically, for a Φ100mm test hole: about 5 kg / package; for a Φ150mm test hole: about 8 kg / package;

[0058] On-site mixing: Pour the dry material into a special mixing pot, initially mix it evenly with a pointed hand trowel, accurately measure 200 - 450 mL of clean water and add it, and continue mixing until the material is uniform and there is no dry material;

[0059] S4: Layered filling construction

[0060] Layered scheme:

[0061] ≤ 20 cm thickness: Construct in 2 layers;

[0062] > 20 cm thickness: Construct in 3 layers;

[0063] The top 5 cm uses the same asphalt concrete material as the original road surface;

[0064] Pouring process: Pour the concrete in portions through a special funnel, control the thickness of each layer within the range of 5 - 7 cm, and the interval between layers does not exceed 30 minutes;

[0065] The fifth step: Compaction and forming

[0066] Ramming operation: Use a φ16mm steel rammer (length ≥ 600mm);

[0067] Ramming method:

[0068] For a Φ100mm test hole: Spiral ramming on the hole wall for 15 times + 10 times in the middle;

[0069] Φ150mm test hole: Spiral ramming 25 times on the hole wall + 20 times in the middle;

[0070] The ramming in the upper layer needs to penetrate the lower layer by 2 - 3 cm;

[0071] Surface compaction: Select a special rammer with a matching diameter (95mm / 145mm), and use an electric compactor to vibrate and compact the surface, controlling the number of ramming times until the surface is flat and dense.

[0072] This construction technology ensures the compactness and durability of the test hole filling through standardized operation processes and strict quality control, and can effectively extend the service life of the road surface.

[0073] Advantages of the present invention:

[0074] 1. The filling material of the present invention has a unique material formula, including a composite special cement-based material and a nano-modified material, which greatly improves the compressive strength of the concrete compared with traditional asphalt concrete, can quickly form structural strength, and realizes immediate filling after coring; secondly, by adding waste LDPE and rubber particles, the material is given excellent elastic properties, and the freeze-thaw splitting strength ratio reaches more than 98%, effectively solving the technical problem of easy cracking of traditional filling materials; in addition, the synergistic effect of the composite water repellent and the micro-expansion agent reduces the water seepage coefficient to 0 mL / min, completely blocking water penetration.

[0075] 2. The innovative standardized construction system of the present invention includes three core technologies: First, a standardized test hole pretreatment process, which greatly improves the interfacial bonding strength through steps such as cleaning with special tools and brushing emulsified asphalt; second, an accurate material metering and mixing system, using pre-packaged dry materials and quantitative water addition to ensure that the mixing ratio error is controlled within ±1%; third, a scientific layered construction method, through the cooperation of spiral ramming and special compaction equipment, making the filling density reach more than 98%.

[0076] 3. The present invention realizes multi-dimensional cost optimization: In terms of material cost, the use of renewable resources (waste tire rubber, LDPE, etc.) greatly reduces the material cost. In terms of construction efficiency, through the standardized process and fast hardening characteristics (opening to traffic in 4 hours), the single-point construction time is greatly shortened; in terms of long-term benefits, the service life of the filled part is greatly extended (can be extended to 8 - 10 years), greatly reducing the road maintenance frequency.

[0077] 4. The present invention uses a funnel to assist in filling the hole, making the hole filling operation more standardized and avoiding the phenomenon of polluting the road surface during the hole filling operation; using the method of layered filling, standard ramming with a rammer, and then vibrating and compacting, standardizes the operation behavior, ensures the compactness of the test hole filling, improves the overall consistency of the road surface quality, and extends the service durability of the road surface.

[0078] 5. The present invention effectively promotes the resource utilization of solid waste by consuming waste tire rubber; by avoiding the dust pollution and material waste generated by traditional processes, it reduces carbon emissions during construction; in addition, the smooth filling quality greatly reduces vehicle noise and improves driving comfort.

[0079] 6. The systematic quality assurance system of the present invention includes: material gradation control, process parameter standardization, and supporting special tools, ensuring a significant improvement in the project qualification rate.

[0080] 7. Through the organic combination of material innovation and process innovation, the present invention has achieved a qualitative leap in the repair quality after road core sampling inspection, providing reliable technical support for the quality control of highway construction and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings. Among them:

[0082] Figure 1 It is a bar chart comparing the performance of the filling materials in Embodiment 1 and Embodiment 2 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0083] In order to make the above objects, features, and advantages of the present invention more obvious and understandable, the following will make a detailed description of the specific embodiments of the present invention with reference to the accompanying drawings of the specification.

[0084] Many specific details are set forth in the following description in order to fully understand the present invention, but the present invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar promotions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0085] Secondly, the so-called "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that can be included in at least one implementation manner of the present invention. The "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that mutually excludes other embodiments.

[0086] Embodiment 1

[0087] This is the first embodiment of the present invention, which provides a filling material for the core sampling test hole of the road structure layer. The composition (mass ratio) of the filling material is specifically as follows:

[0088] Composite special cement-based material: 1 part;

[0089] Composite nano-modified material: 1.58 parts;

[0090] Sand: 2.35 parts;

[0091] Stone: 2.65 parts;

[0092] Composite water repellent: 0.07 part;

[0093] High-efficiency composite water reducer: 0.03 part;

[0094] Thixotropic lubricant: 0.06 part;

[0095] Micro-expansion agent: 0.08 part;

[0096] Waste LDPE particles: 0.1 part;

[0097] Rubber particles: 0.15 part;

[0098] Water: 0.46 part;

[0099] Dry-mix the above materials in a blender, and then add water and stir to form a uniform nano-scale super-tough cementitious material concrete.

[0100] The filling method of the filling material prepared according to the above material composition (mass ratio) is as follows:

[0101] (1) Test hole cleaning:

[0102] Use a sponge or towel to suck out the accumulated water in the test hole, and use a clamp to clean the residual debris;

[0103] Wipe the inner wall and bottom of the test hole with a dry cloth to ensure there is no floating dust;

[0104] Inject 150 mL of fast-setting emulsified asphalt into the test hole, and evenly brush the inner wall of the test hole with a brush.

[0105] (2) Pouring and compaction:

[0106] Pour the mixed concrete into the Φ100 mm test hole in layers, with each layer about 5 cm thick;

[0107] Use a steel tamper to insert and tamp 15 times along the hole wall in a spiral manner, and tamp 10 times in the middle;

[0108] When pouring the upper layer, insert the tamper 1 - 2 cm into the lower layer, and finally level and tamp.

[0109] 3. Performance verification (a certain highway reconstruction and expansion project)

[0110] Freeze-thaw splitting strength ratio (-18 °C, 5 cycles): 97%;

[0111] Water penetration coefficient: 0 mL / min;

[0112] It shows that the filling material has excellent freeze-thaw resistance and waterproof performance, far superior to traditional cold patch materials and hot mix asphalt mixtures.

[0113] Example 2

[0114] This is the second embodiment of the present invention. The difference between this embodiment and the first embodiment is that the composition (mass ratio) of the filling material is specifically as follows:

[0115] Composite special cement-based material: 1 part;

[0116] Composite nano-modified material: 2.26 parts;

[0117] Sand: 2.18 parts;

[0118] Stone: 2.83 parts;

[0119] Composite water repellent: 0.08 part;

[0120] High-efficiency composite water reducer: 0.05 part;

[0121] Thixotropic lubricant: 0.07 part;

[0122] Micro-expansion agent: 0.08 part;

[0123] Waste LDPE particles: 0.08 part;

[0124] Rubber particles: 0.15 part

[0125] Water: 0.44 part.

[0126] 2. Filling method

[0127] The filling method of the filling material prepared according to the above material composition (mass ratio) is the same as the cleaning method in the steps of Example 1, but the dosage of emulsified asphalt is adjusted to 120 mL;

[0128] Fill the Φ150 mm test hole, with each layer about 7 cm thick, insert and tamp the hole wall 25 times, and insert and tamp in the middle 20 times.

[0129] 3. Performance verification

[0130] Freeze-thaw splitting strength ratio (-18 °C, 5 cycles): 98.2%;

[0131] Permeability coefficient: 0 mL / min;

[0132] It shows that this ratio also has excellent freeze-thaw resistance and waterproof performance, and is suitable for filling test holes with a larger diameter.

[0133] The test detection results of the filling materials in the above Example 1 and Example 2 are shown in the following table:

[0134]

[0135] The bar chart of the performance comparison of the filling materials in the above-mentioned Example 1 and Example 2 is as Figure 1 shown.

[0136] From the test data of the above Examples 1 to 2, the following conclusions can be drawn:

[0137] 1. The comparative analysis results of the cyclic freeze-thaw splitting strength of the nano-scale super-tough cementitious material concrete introduced in the present invention and the traditional filling technology and materials show that the performance of the nano-scale super-tough cementitious material concrete introduced in the present invention is the best;

[0138] 2. The on-site results reveal the coefficient of water permeability and its analysis overview after filling the test holes with different materials; specifically, for the test holes filled with the nano-scale super-tough cementitious material concrete introduced in the present invention, the coefficient of water permeability is extremely low, almost reaching the non-water-permeable state, thus effectively avoiding the occurrence of pavement water damage; in contrast, for the test holes filled with the cold patch material and hot mix material in the prior art, the coefficient of water permeability is significantly higher, failing to meet the design technical specification requirements, and thus being prone to early water damage problems.

[0139] 3. The application of the nano-scale super-tough cementitious material concrete of the present invention in filling test holes can effectively ensure the overall quality level of the pavement and significantly improve the service durability of the pavement.

[0140] 4. Aiming at the limitations in the selection of filling materials and the treatment of filling technology for the core drilling test holes of the conventional pavement structure layer, the present invention proposes an innovative filling material and method for the core drilling test holes of the road structure layer. This innovation aims to provide diverse and easy-to-operate filling options for the test hole filling operators, further standardize the test hole filling operation process, ensure the stable and reliable quality after filling, thereby improving the overall performance of the pavement structure layer, and ultimately achieving the purpose of extending the service life of the pavement.

[0141] 5. The technical implementation and performance verification of the present invention are widely applicable to various pavement structure types such as pavement base course, asphalt middle surface course and lower surface course, providing scientific and reasonable test hole filling materials and methods for the core drilling activities in the engineering construction and maintenance stages and the later quality evaluation and detection, and providing strong support for pavement maintenance and management.

[0142] In summary, the main differences between the present invention and the existing test hole filling process technologies are as follows:

[0143] 1. The test hole filling concrete material in the present invention is nano-scale super-tough cementitious material concrete, which can quickly fill the test holes, that is, the test holes can be filled in time after on-site core drilling;

[0144] 2. The nano-scale super-tough cementitious material concrete of the present invention is reasonably designed, and the concrete strength is superior to that of the asphalt concrete filled by the traditional method.

[0145] 3. The present invention uses a professional method to clean the cored test hole, standardizes the cleaning behavior of the test hole, and avoids the problem that the quality after filling fails to meet the expected effect due to pollution of the test hole.

[0146] 4. The present invention coats emulsified asphalt on the clean test hole wall, aiming to enhance the adhesion between the filling material and the original road surface structure, and at the same time avoid the tiny gaps between the filling material and the road surface structure.

[0147] 5. The present invention first quantitatively fills the mixture into bags according to a specific ratio, ensures its measurement accuracy, and at the same time avoids the problem of waste of material resources.

[0148] 6. The present invention stipulates the mixing operation method, first mixes the dry mixture evenly, and then adds the specified amount of water to ensure the uniformity of the concrete mixing.

[0149] 7. The present invention unifies the method of layered filling of the test hole and ramming it a specified number of times, ensuring that the concrete is basically in a dense state after filling and ramming.

[0150] 8. The present invention uses a special ramming device to ram and vibrate the concrete after filling and ramming, so that the concrete truly reaches a dense state.

[0151] 9. The quality assurance of the test hole filling of the present invention is superior to the traditional method, the on-site operation is convenient, and the test hole filling efficiency is high; after the test hole of the present invention is filled, the overall performance of the test hole part is consistent with that of the road surface structure, avoiding the phenomenon of early diseases on the road surface.

[0152] It should be understood that in the development process of any actual implementation, such as in any engineering or design project, a large number of specific implementation decisions can be made. Such development efforts may be complex and time-consuming, but for those ordinary technical personnel who benefit from this disclosure, without excessive experimentation, the development efforts will be a routine work of design, manufacturing and production.

[0153] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A core sampling test hole filling material for road structural layers, characterized in that: The filling material is composed of a composite special cement-based material, a composite nano-modified material, aggregate, yellow sand, rubber particles, water, early strength agent, composite water repellent, high-efficiency composite water reducer, thixotropic lubricant, expansive agent, and waste LDPE particles. The filling material is physically mixed with the above components to form a nano-scale super-tough cementitious material concrete.

2. The core sampling test hole filling material for the road structure layer according to claim 1, characterized in that: The composite special cement-based material is composed of tricalcium silicate / calcium oxide, dicalcium silicate / silicon oxide, tricalcium aluminate / aluminum oxide, and tetracalcium aluminoferrite / iron oxide in proportion, and the preparation temperature is controlled at 1500 °C.

3. The core sampling test hole filling material for the road structure layer according to claim 2, characterized in that: The composite nano-modified material is prepared by the sol-gel method with a 1:1 ratio of porous silicon and amphiphilic nano-silica, and the dosage is 1.2% - 5.5% of the cement mass.

4. The core sampling test hole filling material for the road structural layer according to claim 3, characterized in that: The composite water repellent is composed of a composite of silicone-based and lipid-based water repellents, and the dosage is 0.5% - 1.0% of the cement mass.

5. The core sampling test hole filling material for the road structure layer according to claim 4, characterized in that: The high-efficiency composite water reducer is prepared by the sulfonation reaction of naphthalene sulfonate formaldehyde condensate and superplasticizer, and the dosage is 0.02% - 0.3% of the cement mass.

6. The filling method of the core drilling test hole filling material for the road structure layer according to claim 5, characterized in that: The expansive agent is composed of natural anhydrous gypsum, natural alunite, and calcined coal gangue, and the admixture amount is 0.03% - 0.5% of the cement dosage.

7. The filling method of the core sampling test hole filling material for the road structure layer as described in claim 6, characterized in that: It includes the following specific steps: S1: Trial hole cleaning: After removing the accumulated water and debris in the trial hole, apply quick-setting emulsified asphalt. S2: Material preparation: Dry-mix the components of the above-mentioned filling material in proportion and quantitatively bag them. S3: Mixing and pouring: Mix the concrete on-site according to the water-cement ratio, pour it into the trial hole in layers and insert and tamp it densely, and finally level and tamp it.

8. The filling method of the core drilling test hole filling material for the road structure layer according to claim 7, characterized in that: In step S1, the dosage of the quick-setting emulsified asphalt is 100 mL - 180 mL, and the application method is to evenly brush it up with a brush.

9. The filling method of the core drilling test hole filling material for the road structure layer according to claim 8, characterized in that: In step S3, the number of times of layer-by-layer ramming is set according to the diameter of the trial hole. For a Φ100 mm trial hole, the hole wall is rammed 15 times and the middle is rammed 10 times; for a Φ150 mm trial hole, the hole wall is rammed 25 times and the middle is rammed 20 times.

10. The filling method of the core drilling test hole filling material for the road structural layer as described in claim 9, characterized in that: In step S3, use a steel rammer to ram in a spiral shape along the wall of the trial hole, and the upper layer ramming needs to be inserted into the lower layer.

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