Liquid supplementing and slurry extracting construction technology based on graded broken stone structure and application of liquid supplementing and slurry extracting construction technology

Abstract

The invention relates to a liquid supplementing and slurry extracting construction process based on a graded broken stone structure and application of the liquid supplementing and slurry extracting construction process, and belongs to the technical field of road engineering. The process provided by the invention is suitable for transforming a low-grade cement road into an asphalt pavement under medium and light traffic volume, adopts an embedded compact grading design, adopts a plant mixing method to mix graded broken stones, and adopts a liquid supplementing and slurry extracting process to improve the modulus of a graded broken stone layer, so that the upward development of reflection cracks can be effectively inhibited and delayed, and the pavement quality is improved. And in addition, the construction cost of the reconstruction scheme is low, the reconstruction speed is high, and the construction period is short.

Description

Technical Field

[0001] This invention belongs to the field of road engineering technology and relates to a liquid replenishment and slurry raising construction process based on graded crushed stone structure and its application. Background Technology

[0002] Currently, there are three main types of common "white-to-black" road resurfacing processes for cement roads. The first type is the crushing process: this involves crushing the existing cement slabs to completely eliminate stress concentration, addressing the reflective cracking problem that often occurs when asphalt is overlaid on cement pavements at its source. Common processes include multi-hammer crushing, resonant crushing, and micro-crack homogenization. However, because crushing cement slabs leads to a significant decrease in overall strength, it often requires the addition of a new water-stabilized base structure, greatly increasing the pavement thickness. Some crushing processes are also quite expensive. The second type is the interlayer overlay process: this involves adding a special interlayer material at the joints of the cement slabs. For example, anti-crack tape, geotextile, fiberglass grid, and polyester fiberglass cloth are used. However, the final anti-crack effect of these materials cannot effectively prevent the development of reflective cracks. Moreover, they are often damaged during the paving and compaction of the asphalt layer after paving, failing to solve the problem of reflective cracks. The third type is the stress-absorbing layer overlay process: As a highly elastic and flexible transition layer, the stress-absorbing layer can effectively absorb the stress concentration generated by the slab joints, protecting the upper asphalt overlay from reflective cracks. It can also make full use of the original high strength and high load-bearing capacity of the cement pavement, so the overall overlay thickness is relatively thin. Therefore, the stress-absorbing layer overlay process is particularly suitable for roads with good original cement pavement strength, small deflection, few slab defects, and tight construction schedules for "white-to-black" road renovation. However, if the traditional 1-2cm thick high-elasticity stress-absorbing layer (such as rubber asphalt macadam seal) technology is used, the defects of the existing cement pavement (such as broken slabs, voids, misalignments, etc.) must be accurately identified and thoroughly resolved before the overlay can be stable and reflective cracks will not develop upwards. Therefore, it is not suitable for low-grade highways (including rural roads).

[0003] The construction technology conditions for low-grade highways are limited. If the cement road is completely excavated, the base layer needs to be rebuilt, which is time-consuming and costly. Common methods are difficult to properly treat the defects of the original cement pavement. Therefore, this invention addresses the above problems by developing a low-cost, high-quality white-to-black conversion solution for low- and medium-grade highways. Summary of the Invention

[0004] The purpose of this invention is to provide a liquid replenishment and grouting construction process based on graded crushed stone structure and its application. This process is suitable for low-cost reconstruction of low-grade cement roads (third-grade roads, fourth-grade roads, and rural roads) to asphalt pavement under medium to light traffic volume. It is low-cost and fast.

[0005] The objective of this invention can be achieved through the following technical solutions: A liquid replenishment and grouting construction process based on graded crushed stone structure includes the following steps: S1, Interlocking dense graded crushed stone layer paving: On the old cement panel, a layer of dense-grained graded crushed stone mixture made of limestone aggregate is laid, with a thickness of 10-15cm. The gradation design of the crushed stone mixture ensures that the passing rate of the mixture through a 0.075mm sieve is 3.5-7%. S2, replenishing fluid and extracting plasma: After the graded crushed stone layer is laid and compacted, a liquid replenishment and slurry raising process is used: S21. Apply water or a special diluent evenly in two applications: The first application can be direct water application, with a rate of 3~3.5 kg / m². 2 After an interval of 5-6 minutes, apply the special diluted solution a second time, at a rate of 3-3.5 kg / m². 2 During the second application, the diluent is obtained by mixing and diluting the additive solution with water at a volume ratio of 1:10. S22. Vibratory compaction: Immediately after the diluted liquid is sprayed, use a single steel drum roller with a capacity of ≥26 tons to compact the mixture twice in a strong vibration mode at a speed of 1.6~1.8km / h. S23, Static Compaction: Switch the road roller to static compaction mode and perform rapid back-and-forth compaction at a speed of 4~6km / h; S3. Construction of emulsified asphalt waterproofing undercoat: On the layer after step S2, slow-cracking emulsified asphalt and crushed stone with a particle size of 3-5mm are sprayed to form an emulsified asphalt waterproof undersealing layer; wherein the spraying amount of the emulsified asphalt is 1.0-1.2kg / m³. 2 The amount of gravel spread is 7~8 kg / m³. 2 ; S4. Asphalt surface overlay: On top of the emulsified asphalt waterproof underseal, an asphalt concrete surface layer is laid according to the estimated cumulative traffic volume.

[0006] As a preferred technical solution of the present invention, in step S1, when the old cement panel is severely broken, cracked, and shaken, it needs to be replaced.

[0007] As a preferred technical solution of the present invention, in step S1, the skeleton-dense graded crushed stone mixture is mixed by plant mixing method.

[0008] As a preferred embodiment of the present invention, in step S1, the gradation design of the graded crushed stone mixture ensures that the passing rate of the mixture through a 31.5mm sieve is 100%, the passing rate through a 26.5mm sieve is 95-100%, the passing rate through a 19.0mm sieve is 72-82%, the passing rate through a 16.0mm sieve is 65-75%, the passing rate through a 13.2mm sieve is 57-70%, the passing rate through a 9.5mm sieve is 42-60%, the passing rate through a 4.75mm sieve is 25-35%, the passing rate through a 2.36mm sieve is 16-30%, the passing rate through a 1.18mm sieve is 11-22%, and the passing rate through a 0.60mm sieve is 7-15%.

[0009] As a preferred embodiment of the present invention, in step S21, the additive liquid is composed of the following components in mass percentage: 1.0-2.0% polyvinyl alcohol, 0.1-0.5% hydroxypropyl guar gum, 0.05-0.15% borax, 0.1-0.5% 3-aminopropyltriethoxysilane, and the balance being water.

[0010] As a preferred embodiment of the present invention, in step S4, the step of paving the asphalt concrete surface layer according to the estimated traffic volume specifically includes: When the cumulative traffic volume is less than 4×10 6 At that time, the paving thickness of the graded crushed stone layer is 10~12cm, and an additional 5~6cm thick layer of AC-16 modified asphalt concrete is laid. When the cumulative traffic volume is 4×10 6 ~8×10 6 The graded crushed stone layer is 12-15cm thick, and an 8cm thick ATB-25 lower layer and a 4cm thick modified asphalt AC-13 upper layer are added.

[0011] As a preferred embodiment of the present invention, in step S3, the emulsified asphalt is prepared from the following raw materials by weight percentage: 58-63% base asphalt, 2-3% slow-cracking cationic emulsifier, 3-5% modifier, 0.1-0.3% penetrant, 0.1-0.3% calcium chloride, 1-2% modified bentonite, 0.1-0.2% pH adjuster, and the balance being water.

[0012] As a preferred embodiment of the present invention, the penetrant is fatty alcohol polyoxyethylene ether, the modifier is an aqueous SBR latex and ethylene-vinyl acetate copolymer with a mass ratio of 3:1, the pH adjuster is hydrochloric acid, and the slow-cracking cationic emulsifier is a quaternary ammonium salt surfactant.

[0013] As a preferred embodiment of the present invention, the preparation process of the aminated bentonite is as follows: 3-Aminopropyltriethoxysilane was mixed with a 90% (v / v) aqueous ethanol solution, and the pH was adjusted to 4.5–5.0. The mixture was stirred at 300 rpm for 20–35 min at room temperature. Bentonite was then added and ultrasonically dispersed. The mixture was stirred at 400 rpm for 4 h at 65–75 °C. After stirring, the mixture was filtered, washed with a 1:1 (v / v) aqueous ethanol solution, vacuum dried at 60 °C for 6 h, ground, and passed through a 200-mesh sieve to obtain aminated bentonite. The ratio of bentonite to aqueous ethanol solution was 1:20 g / mL, and the amount of 3-aminopropyltriethoxysilane was 8–12% of the bentonite. Acrylamide, acryloyloxyethyltrimethylammonium chloride, and aminated bentonite were mixed with deionized water in a mass ratio of (0.45~0.5):0.2:1). Under nitrogen protection, the pH of the system was adjusted to 3.5~4.5. Then, 0.5% of the mass of acrylamide, ammonium persulfate, and 0.4% of the mass of acrylamide, sodium bisulfite were added. The temperature was raised to 40~47℃ and stirred for 5 hours to obtain modified bentonite.

[0014] An application of a liquid-filling and slurry-raising construction process based on graded crushed stone structure, wherein the liquid-filling and slurry-raising construction process can be applied to the conversion of low-grade cement roads into asphalt pavements under medium and light traffic volumes.

[0015] Traditional graded crushed stone design primarily considers CBR value and compaction degree, pursuing a stable or continuous gradation of the aggregate skeleton. This invention, however, is applicable to the replenishment and slurry enhancement process. Through gradation design, the graded crushed stone is limestone, employing a dense skeleton gradation with a higher proportion of coarse aggregate. Simultaneously, fine aggregate is added according to the amount of voids in the coarse aggregate skeleton, resulting in greater compaction and lower residual porosity. This facilitates the formation of an interlocking-dense structure with high cohesion and internal friction angle. The 0.075mm passing rate (powder content) is 3.5~7%, which is the material basis for effective "slurry enhancement," forming a dense surface slurry layer.

[0016] Graded crushed stone is often considered a loose, "flexible base course" that only provides stress diffusion. Its compaction relies on vibration and rolling, it has a limited modulus, and it is susceptible to water damage.

[0017] This invention is no longer a simple compaction, but actively achieves "slurry lifting" by precisely controlling the replenishment of liquid (two quantitative water sprays and special diluent) and specific rolling (first strong vibration followed by fast static pressure). This is a dynamic, precision-controlled process that can change the internal structure and surface state of the material.

[0018] By employing a liquid-filling and slurry-raising construction process, vibration compaction is carried out under high moisture content conditions. Water acts as a lubricant, causing some small particles and laitance to float to the surface during vibration compaction. This further interlocks the coarse aggregate in the graded crushed stone, forming a dense skeleton structure. Soil and particles smaller than 0.075mm are carried out of the structural layer by excess water. The coarse aggregate is interlocked together, creating a mosaic-like arrangement on the surface. Although no cement is added, it can still achieve a similar compaction effect to a water-stabilized base course. Therefore, after drying, the graded crushed stone layer will form a stable compacted layer. This is equivalent to achieving performance similar to a water-stabilized base course at a low cost (without cement). The overall structural integrity of the graded crushed stone base course is enhanced, and the elastic modulus of the graded crushed stone layer is further improved. Moreover, this construction process does not significantly increase construction costs compared to the original graded crushed stone construction process.

[0019] Specifically, the first watering is to soak and lubricate the particles and prepare a humid environment; the second watering uses water as a medium and carrier to spray a diluent, which carries, transports and evenly distributes the functional components (PVA, hydroxypropyl guar gum, borax, silane) to the surface and pores of the graded crushed stone layer. Hydroxypropyl guar gum, as a highly thickening polysaccharide, has long chains that interpenetrate with PVA molecules and PVA-borax networks through hydrogen bonds and physical entanglement, forming an interpenetrating polymer network. This significantly improves the system's zero-shear viscosity and water-holding capacity, ensuring a uniform, stable, and non-segregating slurry. Simultaneously, it enhances the overall strength of the network, enabling it to support more fine particles. Furthermore, the interaction between PVA and borax forms a three-dimensional network supporting the slurry. The ethoxy groups of KH-550 rapidly hydrolyze into highly reactive silanols, which can form hydrogen bonds with the hydroxyl groups of PVA / hydroxypropyl guar gum, lightly incorporating into the network and optimizing the interfacial properties of the substrate. These four elements work synergistically to simultaneously strengthen the slurry at both the slurry itself and the "slurry-substrate interface," ensuring both slurry lifting efficiency and stability.

[0020] The emulsified asphalt underseal used in this invention, after undergoing a replenishment and slurry-raising process, forms a high-strength and tough asphalt layer through the combined action of its components. This achieves microscopic anchoring and chemical bonding with the base layer, preventing the waterproof underseal from separating from the crushed stone layer and providing a solid foundation for the superstructure.

[0021] The flexibility of SBR is supported by the rigid skeleton of EVA, which greatly improves the ability to resist rutting at high temperatures. The SBR component helps to improve elasticity and effectively absorb and disperse stress from the joints of old roads. EVA improves the overall film-forming properties and adhesion, making the asphalt film denser and stronger.

[0022] The formulation simultaneously includes a polymer modifier (providing toughness), a nonionic surfactant as a penetrant (effectively reducing emulsion surface tension and improving wettability), and calcium chloride (as a stabilizer and accelerating demulsification). The modified bentonite is first aminated to improve dispersion stability and prevent uneven reaction caused by agglomeration. These amino groups provide stable and highly active reaction sites for subsequent polymer grafting, helping polymer chains to graft onto the bentonite via chemical bonds. Through amination and grafting with cationic polyacrylamide, the resulting modified bentonite forms a strong dual stabilizing effect in the emulsion through steric hindrance and electrostatic repulsion. Therefore, the polymer chains on the surface of the modified bentonite are intertwined and synergistically work with bentonite nanosheets to construct a stronger organic-inorganic interpenetrating network structure, producing a more controllable and stable thixotropic and thickening effect, and improving interlayer bonding strength. Through a dual mechanism of physical barrier and chemical-physical adsorption, the high-temperature movement of asphalt molecular chains is more effectively restricted, thereby significantly improving the softening point and rutting resistance of the composite system. Due to the steric hindrance and electrostatic repulsion of the cationic polymer, the stable network system formed when left to stand maintains high viscosity, which can actively prevent the asphalt particles from floating and agglomerating and the modifier from settling and segregating, thus achieving excellent stability.

[0023] The beneficial effects of this invention are: Compared to existing white-to-black asphalt overlay technology, the process proposed in this invention features a graded crushed stone layer that is easy to construct, utilizing locally available materials. This effectively inhibits and delays the upward development of reflective cracks, extending the pavement's service life. Furthermore, this renovation scheme is cost-effective, fast-paced, and has a short construction period, making it suitable for the renovation of low-grade cement roads. For existing cement road defects, only severely broken, cracked, or wobbly slabs require replacement; other defects generally require no treatment, making it suitable for the construction conditions of low-grade highways. Simultaneously, the densely interlocked graded crushed stone layer and asphalt surface layer in this invention form a robust composite structural system. This new system effectively disperses stress, preventing minor defects and localized voids in the underlying old pavement from posing a fatal threat to the new structure. This greatly simplifies the construction process and significantly reduces treatment costs. Attached Figure Description

[0024] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0025] Figure 1 This is a process diagram of the present invention; Figure 2 This is a diagram showing the original road surface condition in Example 1; Figure 3 This is a construction diagram of graded crushed stone compaction using the liquid replenishment and slurry raising process in Example 1; Figure 4This is a diagram showing the effect of drying after the liquid replenishment and pulp extraction steps in Example 1. Detailed Implementation

[0026] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with embodiments, is provided below.

[0027] It should be noted that, unless otherwise specified, the present invention does not specifically limit the source of the raw materials used in the following embodiments. Commercially available products or products prepared by conventional preparation methods that are well known to those skilled in the art can be used. Experimental methods that do not specify specific conditions are all conventional methods and conventional conditions well known in the art.

[0028] Example 1 Road surface issues: (1) The original cement concrete panel has low strength and uneven thickness (the thinnest part is only 10cm), which leads to severe breakage of the cement panel after resonance crushing, making it difficult to form an interlocking structure and resulting in complete loss of structural strength. (2) The original cement pavement had no base structure, and the cement slabs were laid directly on the untreated subgrade. (3) The original road surface is low in elevation and has paddy fields on both sides, with a high groundwater level.

[0029] Construction plan: S1, Interlocking dense graded crushed stone layer paving: Based on the condition of the old cement panels, severely broken, cracked, and wobbly panels need to be replaced, while other panel defects do not require treatment. On the old cement panels, an interlocking dense gradation design is adopted, and the graded crushed stone is mixed using the plant mixing method. A layer of skeleton-dense graded crushed stone mixture made of limestone aggregate is laid with a thickness of 12cm. Graded crushed stone mixture design: The passing rates of the 31.5mm sieve openings were 100%, 26.5mm sieve openings were 98%, 19.0mm sieve openings were 81.4%, 16.0mm sieve openings were 71.4%, 13.2mm sieve openings were 61.6%, 9.5mm sieve openings were 52.1%, 4.75mm sieve openings were 40.5%, 2.36mm sieve openings were 26.1%, 1.18mm sieve openings were 18.4%, 0.60mm sieve openings were 12.7%, and 0.075mm sieve openings were 3.8%. S2, replenishing fluid and extracting plasma: After the graded crushed stone layer is laid and compacted, a liquid replenishment and slurry raising process is used: S21. Apply water or a special diluent evenly in two applications: For the first application, the application rate is 3.3 kg / m². 2 After a 6-minute interval, the added solution was mixed with water at a volume ratio of 1:10 to obtain a diluted solution. This diluted solution was then used for a second application, with a application rate of 3.3 kg / m². 2 The additive solution consists of the following components by mass percentage: 1.7% polyvinyl alcohol, 0.4% hydroxypropyl guar gum, 0.1% borax, 0.4% 3-aminopropyltriethoxysilane, and the balance being water; S22. Vibratory compaction: Immediately after the diluted liquid is sprayed, use a single steel drum roller with a capacity of ≥26 tons to compact the mixture twice in a strong vibration mode at a speed of 1.8 km / h. S23, Static Compaction: Switch the road roller to static compaction mode and perform rapid back-and-forth compaction at a speed of 6km / h; after construction, conduct deflection testing again, and the deflection data is within 10 (0.01mm); since the graded crushed stone layer does not contain inorganic binders such as cement and lime, there is no need to close the road after construction, and traffic can continue normally. S3. Construction of emulsified asphalt waterproofing undercoat: After the graded crushed stone layer is thoroughly dried, slow-cracking emulsified asphalt and crushed stone with a particle size of 3-5 mm are sprayed to form an emulsified asphalt waterproof undersea layer; wherein the amount of emulsified asphalt sprayed is 1.1 kg / m³. 2 The amount of gravel spread is 8 kg / m³. 2 ; S4. Asphalt surface overlay: Above the emulsified asphalt waterproof underseal, the asphalt overlay structure consists of a 4cm thick AC-13 top layer and an 8cm thick ATB-25 bottom layer.

[0030] The emulsified asphalt used is composed of the following raw materials by weight percentage: 61% base asphalt, 2.5% quaternary ammonium salt surfactant (MQK-1M), 4% waterborne SBR latex and EVA emulsion (Guangdong Hualitai Chemical Co., Ltd., model EP706K) in a mass ratio of 3:1, 0.2% fatty alcohol polyoxyethylene ether, 0.2% calcium chloride, 1.5% modified bentonite, 0.15% hydrochloric acid, and the balance being water. The concentration of the hydrochloric acid used is 35%, and the base asphalt is No. 70 Grade A road petroleum asphalt.

[0031] 3-Aminopropyltriethoxysilane was mixed with a 90% (v / v) aqueous ethanol solution, and the pH was adjusted to 4.5–5.0. The mixture was stirred at 300 rpm for 25 min at room temperature. Bentonite was then added and ultrasonically dispersed. The mixture was stirred at 400 rpm for 4 h at 70 °C. After stirring, the mixture was filtered, washed with a 1:1 (v / v) aqueous ethanol solution, vacuum dried at 60 °C for 6 h, ground, and passed through a 200-mesh sieve to obtain aminated bentonite. The ratio of bentonite to aqueous ethanol solution was 1:20 g / mL, and the amount of 3-aminopropyltriethoxysilane was 10% of the bentonite. Acrylamide, acryloyloxyethyltrimethylammonium chloride, and aminated bentonite were mixed with deionized water in a mass ratio of (0.45~0.5):0.2:1, with a solid-liquid ratio of 1g:12mL for the aminated bentonite to deionized water. Under nitrogen protection, the pH of the system was adjusted to 3.5~4.5 with 1M hydrochloric acid solution. Then, 0.5% ammonium persulfate and 0.4% sodium bisulfite (by mass of acrylamide) were added. The temperature was raised to 40~47℃ and stirred for 5h. The mixture was then washed with anhydrous ethanol, centrifuged, and dried in a vacuum drying oven at 60℃ for 30h to obtain modified bentonite.

[0032] according to Figure 4 It is understood that the construction process in this invention can cause the coarse aggregate in the graded crushed stone to be interlocked to form a dense skeleton structure and a stable hardened layer. The process of this invention can effectively target this type of low-grade road surface and repair the original road surface at low cost.

[0033] Comparative Example 1 The construction process adopts the traditional method of directly adding an asphalt structural layer after resonant crushing.

[0034] It was found that after resonance crushing, the road surface deflection increased rapidly, with the deflection measured in some sections reaching 600-800 (0.01 mm), and the deflection limit value in soft soil areas reaching 1134 (0.01 mm). It was impossible to directly add an asphalt structural layer. The cement concrete slab with resonance crushing could only be used as a subbase structure. Only after adding a water-stabilized crushed stone base course could an asphalt structural layer be laid. (Even if a water-stabilized layer was added to the soft soil section, its deflection was still very large. After the ATB-25 layer was laid, the top surface deflection measured value still exceeded 100 (0.01 mm). Therefore, the traditional technical solution of directly adding an asphalt structural layer after crushing was not suitable.)

[0035] Comparative Example 2 This comparative example is basically the same as Example 1, except that water is sprayed twice in step S2 in this comparative example, and the rolling process is the same.

[0036] Comparative Example 3 This comparative example is basically the same as Example 1, except that in this comparative example, the second spraying in step S2 uses a diluent containing only hydroxypropyl guar gum.

[0037] Comparative Example 4 This comparative example is basically the same as Example 1, except that the passing rate of the 0.075mm sieve in the graded crushed stone mixture design in this comparative example is 2%. Deflection was measured using FWD on 1km sections of each of Examples 1 and Comparative Examples 2-4. The results are shown in Table 1 below: Table 1 Group <![CDATA[Average value of right deflection detection (50KN load) (10 -2 mm)]]> <![CDATA[Average value of left lane deflection detection (50KN load) (10 -2 mm)]]> Example 1 17.5 16.3 Comparative Example 2 31.1 38.8 Comparative Example 3 39.7 47.4 Comparative Example 4 27.6 25.6 Based on the above data, in Example 1, the average deflection of the right lane was 17.5 mm (0.01 mm), with a standard deviation of 3.29 and a coefficient of variation of 18.8%. The average deflection of the left lane was 16.3 mm (0.01 mm), with a standard deviation of 2.69 and a coefficient of variation of 16.5%. Compared with Comparative Examples 1, 2, 3, and 4, the average deflection was smaller, indicating that the technical solution of the present invention does not damage the original strength of the cement panel, helps to reduce the unevenness of the cement pavement, and results in higher overall strength of the pavement structure.

[0038] Example 2 The emulsified asphalt used is composed of the following raw materials by weight percentage: 60% base asphalt, 2.5% quaternary ammonium salt surfactant (MQK-1M), 4% waterborne SBR latex and EVA emulsion (Guangdong Hualitai Chemical Co., Ltd., model EP706K) in a mass ratio of 3:1, 0.2% fatty alcohol polyoxyethylene ether, 0.15% calcium chloride, 1.5% modified bentonite, 0.15% hydrochloric acid, and the balance being water. The concentration of the hydrochloric acid used is 33%, and the base asphalt is No. 70 Grade A road petroleum asphalt.

[0039] 3-Aminopropyltriethoxysilane was mixed with a 90% (v / v) aqueous ethanol solution, and the pH was adjusted to 4.5–5.0. The mixture was stirred at 300 rpm for 25 min at room temperature. Bentonite was then added and ultrasonically dispersed. The mixture was stirred at 400 rpm for 4 h at 70 °C. After stirring, the mixture was filtered, washed with a 1:1 (v / v) aqueous ethanol solution, vacuum dried at 60 °C for 6 h, ground, and passed through a 200-mesh sieve to obtain aminated bentonite. The ratio of bentonite to aqueous ethanol solution was 1:20 g / mL, and the amount of 3-aminopropyltriethoxysilane was 9% of the bentonite. Acrylamide, acryloyloxyethyltrimethylammonium chloride, aminated bentonite, and deionized water were mixed in a mass ratio of 0.46:0.2:1, with a solid-liquid ratio of 1 g:12 mL for the aminated bentonite to deionized water. Under nitrogen protection, the pH of the system was adjusted to 3.5-4.5 with 1 M hydrochloric acid solution. Then, 0.5% ammonium persulfate and 0.4% sodium bisulfite (by mass of acrylamide) were added. The temperature was raised to 45°C, and the mixture was stirred for 5 hours. After washing with anhydrous ethanol, centrifugation, and drying in a vacuum drying oven at 60°C for 30 hours, modified bentonite was obtained.

[0040] Example 3 The emulsified asphalt used is composed of the following raw materials by weight percentage: 58% base asphalt, 2% quaternary ammonium salt surfactant (MQK-1M), 3% waterborne SBR latex and EVA emulsion (Guangdong Hualitai Chemical Co., Ltd., model EP706K) in a mass ratio of 3:1, 0.1% fatty alcohol polyoxyethylene ether, 0.1% calcium chloride, 1% modified bentonite, 0.1% hydrochloric acid, and the balance is water. The concentration of hydrochloric acid used is 30%, and the base asphalt is No. 70 Grade A road petroleum asphalt.

[0041] 3-Aminopropyltriethoxysilane was mixed with a 90% (v / v) aqueous ethanol solution, and the pH was adjusted to 4.5–5.0. The mixture was stirred at 300 rpm for 20 min at room temperature. Bentonite was then added and ultrasonically dispersed. The mixture was stirred at 400 rpm for 4 h at 65 °C. After stirring, the mixture was filtered, washed with a 1:1 (v / v) aqueous ethanol solution, vacuum dried at 60 °C for 6 h, ground, and passed through a 200-mesh sieve to obtain aminated bentonite. The ratio of bentonite to aqueous ethanol solution was 1:20 g / mL, and the amount of 3-aminopropyltriethoxysilane was 8% of the bentonite. Acrylamide, acryloyloxyethyltrimethylammonium chloride, aminated bentonite, and deionized water were mixed in a mass ratio of 0.45:0.2:1, with a solid-liquid ratio of 1 g:12 mL for the aminated bentonite and deionized water. Under nitrogen protection, the pH of the system was adjusted to 3.5-4.5 with 1 M hydrochloric acid solution. Then, 0.5% ammonium persulfate and 0.4% sodium bisulfite (by mass of acrylamide) were added. The temperature was raised to 45°C, and the mixture was stirred for 5 hours. After washing with anhydrous ethanol, centrifugation, and drying in a vacuum drying oven at 60°C for 30 hours, modified bentonite was obtained.

[0042] Example 4 The emulsified asphalt used is composed of the following raw materials by weight percentage: 63% base asphalt, 3% quaternary ammonium salt surfactant (MQK-1M), 5% waterborne SBR latex and ethylene-vinyl acetate copolymer in a mass ratio of 3:1, 0.3% fatty alcohol polyoxyethylene ether, 0.3% calcium chloride, 2% modified bentonite, 0.2% hydrochloric acid, and the balance being water. The concentration of the hydrochloric acid used is 35%, and the base asphalt is No. 70 Grade A road petroleum asphalt.

[0043] 3-Aminopropyltriethoxysilane was mixed with a 90% (v / v) aqueous ethanol solution, and the pH was adjusted to 4.5–5.0. The mixture was stirred at 300 rpm for 35 min at room temperature. Bentonite was then added and ultrasonically dispersed. The mixture was stirred at 400 rpm for 4 h at 75 °C. After stirring, the mixture was filtered, washed with a 1:1 (v / v) aqueous ethanol solution, vacuum dried at 60 °C for 6 h, ground, and passed through a 200-mesh sieve to obtain aminated bentonite. The ratio of bentonite to aqueous ethanol solution was 1:20 g / mL, and the amount of 3-aminopropyltriethoxysilane was 12% of the bentonite. Acrylamide, acryloyloxyethyltrimethylammonium chloride, aminated bentonite, and deionized water were mixed in a mass ratio of 0.45:0.2:1, with a solid-liquid ratio of 1 g:12 mL for the aminated bentonite and deionized water. Under nitrogen protection, the pH of the system was adjusted to 3.5-4.5 with 1 M hydrochloric acid solution. Then, 0.5% ammonium persulfate and 0.4% sodium bisulfite (by mass of acrylamide) were added. The temperature was raised to 45°C, and the mixture was stirred for 5 hours. After washing with anhydrous ethanol, centrifugation, and drying in a vacuum drying oven at 60°C for 30 hours, modified bentonite was obtained.

[0044] Comparative Example 5 This comparative example is basically the same as Example 2, except that bentonite was not added and the comparative example was not subjected to amination treatment.

[0045] Comparative Example 6 This comparative example is basically the same as Example 2, except that the bentonite in this comparative example has not undergone any modification treatment.

[0046] Comparative Example 7 This comparative example is basically the same as Example 2, except that no modifier was added in this comparative example.

[0047] The emulsified asphalts prepared in Examples 2-4 and Comparative Examples 5-7 were tested according to the test items shown in Table 2.

[0048] Table 2 Group Ductility at 5℃ / cm (T 0605) Softening point / °C (T 0606) Penetration at 25℃ (100g, 5s) (T 0604) Storage stability (1 day, %) (T 0655) Example 2 50 85 45.3 0.23 Example 3 48 82 45.0 0.27 Example 4 49 83 45.1 0.25 Comparative Example 5 32 75 50.2 0.52 Comparative Example 6 27 69 54.9 0.63 Comparative Example 7 20 61 58.7 0.71 Based on the above data, it can be seen that the emulsified asphalt prepared by the present invention has excellent performance in terms of high temperature performance (softening point) and low temperature crack resistance (5℃ ductility).

[0049] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A liquid replenishment and grouting construction process based on graded crushed stone structure, characterized in that, Includes the following steps: S1, Interlocking dense graded crushed stone layer paving: On the old cement panel, a layer of dense-grained graded crushed stone mixture made of limestone aggregate is laid, with a thickness of 10-15cm. The gradation design of the crushed stone mixture ensures that the passing rate of the mixture through a 0.075mm sieve is 3.5-7%. S2, replenishing fluid and extracting plasma: After the graded crushed stone layer is laid and compacted, a liquid replenishment and slurry raising process is used: S21. Apply water or a special diluent evenly in two applications: The first application can be direct water application, with a rate of 3~3.5 kg / m². 2 After an interval of 5-6 minutes, apply the special diluted solution a second time, at a rate of 3-3.5 kg / m². 2 During the second application, the diluent is obtained by mixing and diluting the additive solution with water at a volume ratio of 1:

10. S22. Vibratory compaction: Immediately after the diluted liquid is sprayed, use a single steel drum roller with a capacity of ≥26 tons to compact the mixture twice in a strong vibration mode at a speed of 1.6~1.8km / h. S23, Static Compaction: Switch the road roller to static compaction mode and perform reciprocating compaction at a speed of 4~6km / h; S3. Construction of emulsified asphalt waterproofing undercoat: On the layer after step S2, slow-cracking emulsified asphalt and crushed stone with a particle size of 3-5mm are sprayed to form an emulsified asphalt waterproof undersealing layer; wherein the spraying amount of the emulsified asphalt is 1.0-1.2kg / m³. 2 The amount of gravel spread is 7~8 kg / m³. 2 ; S4. Asphalt surface overlay: On top of the emulsified asphalt waterproof underseal, an asphalt concrete surface layer is laid according to the estimated cumulative traffic volume.

2. The grout replenishment and lifting construction process based on graded crushed stone structure according to claim 1, characterized in that, In step S1, if the old cement panel is severely broken, cracked, or shaken, it needs to be replaced.

3. The grout replenishment and lifting construction process based on graded crushed stone structure according to claim 1, characterized in that, In step S1, the skeleton-dense graded crushed stone mixture is mixed using a plant mixing method.

4. The liquid replenishment and slurry raising construction process based on graded crushed stone structure according to claim 1, characterized in that, In step S1, the gradation design of the graded crushed stone mixture ensures that the mixture passes through a 31.5mm sieve with a pass rate of 100%, a 26.5mm sieve with a pass rate of 95-100%, a 19.0mm sieve with a pass rate of 72-82%, a 16.0mm sieve with a pass rate of 65-75%, a 13.2mm sieve with a pass rate of 57-70%, a 9.5mm sieve with a pass rate of 42-60%, a 4.75mm sieve with a pass rate of 25-35%, a 2.36mm sieve with a pass rate of 16-30%, a 1.18mm sieve with a pass rate of 11-22%, and a 0.60mm sieve with a pass rate of 7-15%.

5. The liquid replenishment and slurry raising construction process based on graded crushed stone structure according to claim 1, characterized in that, In step S21, the additive solution is composed of the following components by mass percentage: 1.0-2.0% polyvinyl alcohol, 0.1-0.5% hydroxypropyl guar gum, 0.05-0.15% borax, 0.1-0.5% 3-aminopropyltriethoxysilane, and the balance being water.

6. The liquid replenishment and slurry raising construction process based on graded crushed stone structure according to claim 1, characterized in that, In step S4, the step of paving the asphalt concrete surface layer according to the estimated traffic volume specifically includes: When the cumulative traffic volume is less than 4×10 6 At that time, the paving thickness of the graded crushed stone layer is 10~12cm, and an additional 5~6cm thick layer of AC-16 modified asphalt concrete is laid. When the cumulative traffic volume is 4×10 6 ~8×10 6 The graded crushed stone layer is 12-15cm thick, and an 8cm thick ATB-25 lower layer and a 4cm thick modified asphalt AC-13 upper layer are added.

7. The grout replenishment and lifting construction process based on graded crushed stone structure according to claim 1, characterized in that, In step S3, the emulsified asphalt is prepared from the following raw materials by weight percentage: 58-63% base asphalt, 2-3% slow-cracking cationic emulsifier, 3-5% modifier, 0.1-0.3% penetrant, 0.1-0.3% calcium chloride, 1-2% modified bentonite, 0.1-0.2% pH adjuster, and the balance being water.

8. The grout replenishment and lifting construction process based on graded crushed stone structure according to claim 6, characterized in that, The penetrant is fatty alcohol polyoxyethylene ether, the modifier is a water-based SBR latex and ethylene-vinyl acetate copolymer with a mass ratio of 3:1, the pH adjuster is hydrochloric acid, and the slow-cracking cationic emulsifier is a quaternary ammonium salt surfactant.

9. The grout replenishment and lifting construction process based on graded crushed stone structure according to claim 6, characterized in that, The preparation process of the aminated bentonite is as follows: 3-Aminopropyltriethoxysilane was mixed with a 90% (v / v) aqueous ethanol solution, and the pH was adjusted to 4.5–5.

0. The mixture was stirred at 300 rpm for 20–35 min at room temperature. Bentonite was then added and ultrasonically dispersed. The mixture was stirred at 400 rpm for 4 h at 65–75 °C. After stirring, the mixture was filtered, washed with a 1:1 (v / v) aqueous ethanol solution, vacuum dried at 60 °C for 6 h, ground, and passed through a 200-mesh sieve to obtain aminated bentonite. The ratio of bentonite to aqueous ethanol solution was 1:20 g / mL, and the amount of 3-aminopropyltriethoxysilane was 8–12% of the bentonite. Acrylamide, acryloyloxyethyltrimethylammonium chloride, and aminated bentonite were mixed with deionized water in a mass ratio of (0.45~0.5):0.2:1). Under nitrogen protection, the pH of the system was adjusted to 3.5~4.

5. Then, 0.5% of the mass of acrylamide, ammonium persulfate, and 0.4% of the mass of acrylamide, sodium bisulfite were added. The temperature was raised to 40~47℃ and stirred for 5 hours to obtain modified bentonite.

10. An application of the liquid replenishment and slurry raising construction process based on graded crushed stone structure as described in any one of claims 1-9, characterized in that, The aforementioned liquid replenishment and slurry raising construction process can be applied to the conversion of low-grade cement roads into asphalt pavements under medium to light traffic volumes.

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