CN112195709A

CN112195709A - APR (alkaline peroxide solution) cementing agent for curing permeable wearing course of mountain highway and construction method thereof

Info

Publication number: CN112195709A
Application number: CN202010989175.5A
Authority: CN
Inventors: 侯源涛; 熊政勇; 江为志; 车春海; 张红光
Original assignee: Guizhou Luzhi Engineering Technology Co ltd
Current assignee: Guizhou Luzhi Engineering Technology Co ltd
Priority date: 2020-09-18
Filing date: 2020-09-18
Publication date: 2021-01-08

Abstract

The invention discloses an APR (alkaline peroxide solution) curing agent for curing asphalt pavement of a mountain highway curing wearing layer, which is prepared by mixing the following raw materials in parts by weight: 40-50 parts of heavy naphthenic distilled oil, 30-35 parts of aldehyde asphalt crosslinking agent and 65-70 parts of water. The construction method of the APR curing agent comprises the following steps: 1): pre-treating a road surface; 2): spraying an APR (ammonium sulfate) curing agent; 3): spreading a wearing layer; 4): and (6) rolling and leveling. The APR (alkaline peroxide solution) cementing agent for maintaining the asphalt pavement of the highway cementing wearing layer in the mountainous area has the characteristics of high reducibility, high permeability and low-temperature adaptability, can deeply reduce components of asphalt microscopically, reinforce the original asphalt surface layer macroscopically and activate the performance index of the asphalt macroscopically, and the pavement obtained by the construction method has the performances of high adhesion, high crack resistance, high stability, strong permeability and long service life; meanwhile, efficient and rapid construction of the seepage-consolidation wearing layer of the mountain highway is facilitated, energy conservation and environmental protection are facilitated, and the method is beneficial to wide application.

Description

APR (alkaline peroxide solution) cementing agent for curing permeable wearing course of mountain highway and construction method thereof

Technical Field

The invention relates to the technical field of pavement construction, in particular to an APR (alkaline peroxide solution) curing agent for curing a permeable wearing layer of a mountain highway and a construction method thereof.

Background

Currently, cementation of wearing courses is gaining wide attention as a novel preventive maintenance process. However, when the construction of the penetration wearing layer is carried out on the highway in the mountainous area, the highway meets the unique characteristics of high altitude, large slope, large camber and the like in the mountainous area.

The highway in the mountainous area is often high in altitude, low in air temperature and unstable in climate, so that an APR (alkaline peroxide solution) curing agent needs to be developed, the APR curing agent has the characteristics of high reducibility, high permeability and low-temperature adaptability, can deeply reduce components of asphalt microscopically, strengthens the original asphalt surface layer macroscopically and activates the performance index of the asphalt, and the pavement obtained by the construction method has the performances of rapid penetration reduction, high adhesion, high crack resistance, high stability and long service life; meanwhile, the construction is convenient and efficient, and the method is suitable for the characteristics of high altitude and low temperature.

The highway in the mountain area has a large longitudinal slope and a large transverse slope, and the common curing agent is easy to flow after being sprayed, so that the curing agent of the asphalt surface layer is not uniform. The APR curing agent has the characteristics of high adhesion and rapid penetration and reduction, and the reaction time after spraying is 20-40 min in sunny days and 40-60 min in cloudy days. In addition, the APR curing agent can be sprayed by an intelligent spraying vehicle or manually, and can be manually and accurately sprayed by spraying equipment in a large area of a longitudinal slope and a transverse slope of a mountain highway.

The route of the mountain road is circuitous and tortuous, and the social vehicles have relatively fixed wheel tracks during driving. Therefore, after the permeable wearing layer is applied to the pavement of the mountain highway, the pavement is different from that of plain areas, the condition that the pavement cannot be rolled by a social vehicle is easily generated on the surface layer, the compactness, the flatness and the durability of the pavement of the permeable wearing layer of the mountain highway are seriously influenced, early diseases such as later pavement water seepage, peeling and the like are caused, and the service life is shortened. Aiming at the mountain highway, the construction method innovatively adds a rolling link of leveling equipment. The thickness of the cementation wearing layer is only 1cm, so the balance weight of the leveling equipment has strict limitation, and is generally within 3 tons. The small-weight road rollers within 3 tons in the market are generally steel wheel road rollers, but the steel wheels can push and damage the seepage and consolidation wearing layer structure and stone materials. And the conventional rubber-tyred roller has no small counter weight and is generally over 16 tons. In addition, in order to adapt to the cross slope and the longitudinal slope of a mountain road, the leveling equipment needs to be driven by front and rear wheels, and the structural damage of the penetration wearing layer caused by over-concentrated stress and slipping during climbing is avoided in the operation process.

Disclosure of Invention

The invention aims to solve the technical problem of providing an APR (alkaline peroxide mechanical hardening) penetration and solidification agent for curing a penetration and solidification wearing layer of a mountain highway and a construction method thereof aiming at the characteristics of the mountain highway.

In order to solve the technical problem, the scheme of the invention is as follows:

an APR (alkaline peroxide solution) curing agent for curing a permeable wearing course of a mountain highway, which is prepared by mixing the following raw materials in parts by weight: 40-50 parts of heavy naphthenic distilled oil, 30-35 parts of aldehyde asphalt crosslinking agent and 65-70 parts of water.

The heavy naphthenic distillate oil is heavy naphthenic petroleum light fraction subjected to hydrodesulfurization treatment.

The aldehyde asphalt crosslinking agent is prepared by performing a crosslinking reaction between a coal asphalt tetrahydrofuran extract and a crosslinking agent.

A construction method of an APR (alkaline peroxide solution) cementing agent for curing a permeability wearing course of a mountain highway comprises the following steps:

1): pavement pretreatment: filling cracks, repairing the net cracks, and polishing the marked lines with the thickness of more than 3 mm; removing soil, sundries and accumulated water on the construction pavement;

2): spraying an APR curing agent: when the road surface is flat, the curing agent is filled into the spreading vehicle, the spreading amount of the spreading vehicle is adjusted, and the spreading operation of the construction road surface is implemented; when the road surface is a mountain road and a large area of a longitudinal slope and a transverse slope is adopted, spraying equipment is used for manually and accurately spraying;

3): paving a wearing layer: after the curing agent is fully infiltrated and absorbed and reacts by the original surface layer asphalt and the color is changed from pink to black, a slurry seal paver is adopted for paving and seam treatment;

4): rolling and leveling:

and (4) carrying out rolling and leveling treatment on the paved and joint-treated road surface by adopting a rubber-tyred road roller.

The sufficient infiltration reaction time of the curing agent is as follows: 20-40 min in sunny days and 40-60 min in cloudy days.

The seam treatment comprises transverse seam treatment and longitudinal seam treatment.

Compared with the prior art, the invention has the beneficial effects that:

in the application, the APR (alkaline peroxide solution) cementing agent for maintaining the asphalt pavement of the road cementing wearing layer in the mountainous area has the characteristics of high reducibility, high permeability and low-temperature adaptability, can microscopically deeply reduce components of asphalt, macroscopically reinforce the original asphalt surface layer and activate the performance index of the asphalt, and the pavement obtained by the construction method has the performances of high adhesion, high crack resistance, high stability, strong permeability and long service life; meanwhile, efficient and rapid construction of the seepage-consolidation wearing layer of the mountain highway is facilitated, energy conservation and environmental protection are facilitated, and the method is beneficial to wide application.

Drawings

Fig. 1 is a road surface structure diagram after the construction of the present invention is completed.

Detailed Description

The following further describes the embodiments of the present invention. It should be noted that the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited thereto. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Most of the asphalt adopted by the high-grade pavement is modified asphalt such as TLA, SBS, SBR and the like, but the sources of the modified asphalt are limited, and the cost is higher. In order to develop modified asphalt with more excellent performance and improve the quality improvement and utilization of coal-based heavy products, coal asphalt is adopted to modify petroleum asphalt. In order to reduce the influence of insoluble substances in coal tar pitch residues on the ductility of modified pitch, the petroleum pitch is modified by using a coal tar pitch tetrahydrofuran extract (THFS), compared with matrix pitch, the THFS modified pitch has the advantages of reduced penetration, increased softening point and reduced ductility, compared with BSI BS-369050 penetration grade indexes, the optimum blending amount of the THFS is determined to be 8%, and the optimum blending temperature of the THFS and the matrix pitch is 135 ℃. The ductility, low-temperature performance, ageing resistance and the like of the THFS modified asphalt are further enhanced by a method of adding a cross-linking agent, the modified asphalt added with the cross-linking agent is 2953cm to (-1) (-CH-3), the transmission peak intensity at 2924 cm- (-1) (-CH-2-), 2854 cm- (-1) (-CH-2-), and the transmission peak intensity at 1010 plus 1270 cm- (-1) is C-O-C telescopic vibration and is gradually enhanced, the transmission peak intensity at 770 plus 730 cm- (-1),710 plus 690 cm- (-1), and 770 plus 810 cm- (-1) benzene ring substitution is gradually enhanced, which shows that the modified asphalt and the aldehyde crosslinking agent have a crosslinking reaction, the characteristic functional group C-O-C of the reaction has a strong change, and the benzene ring substitution is increased.

the APR curing agent has the characteristics of high reducibility, high permeability and low-temperature adaptability, can deeply reduce all components of asphalt microscopically, reinforce the original asphalt surface layer macroscopically and activate the performance indexes of the asphalt, and the pavement obtained by the construction method has the performances of quick penetration and reduction, high adhesion, high crack resistance, high stability and long service life; meanwhile, the construction is convenient and efficient, and the method is suitable for the characteristics of high altitude and low temperature.

4): rolling and leveling: and (4) carrying out rolling and leveling treatment on the paved and joint-treated road surface by adopting a rubber-tyred road roller. In operation, the rubber-tyred roller is a dual-drive rubber-tyred roller within 3 tons.

The rolling is increased to make up the flatness and compactness of the surface layer of the cementation wearing layer caused by large road curvature in mountainous areas and insufficient rolling during later driving; the construction strength problem of the permeable and consolidated wearing course at high altitude and low air temperature of the highway in the mountain area is solved.

In this application, before carrying out the preliminary treatment, carry out construction preparation earlier, construction preparation includes following operation and equipment:

A. road condition survey

The road condition survey needs to collect the structural strength of the original road surface, the aging degree of the surface layer asphalt, the rutting condition, the hug of the original road surface, the heavy-load traffic condition, the traffic flow and other information. For the damaged road section, treatment is carried out according to the fourth section 'design for treating the damaged road section' so as to ensure that a working surface meeting the requirements is formed during construction.

B. Asphalt aging test

Through the reconnaissance to the original road surface, select representative highway section to get the core sample, carry out the test detection of pitch ageing index at indoor, the concrete step is as follows:

(1) core drilling and sampling are carried out on the determined construction road section by adopting a core drilling machine;

(2) cutting the cored sample in a laboratory, and cutting a surface layer of 2cm of mixture for later use (according to experience and data, the asphalt aging only occurs within 2cm of the surface layer);

(3) collecting the standby asphalt mixture, softening the mixture in a 100 ℃ oven, soaking the mixture in trichloroethylene, and recovering asphalt by adopting asphalt recovery equipment such as an extractor, a high-speed centrifuge and the like according to the test procedure of the asphalt mixture;

(4) and (4) carrying out needle penetration, ductility and softening point tests on the recycled asphalt, and recording data.

The asphalt aging test is carried out indoors, and the penetration component is sprayed to recover the original pavement aged asphalt to 80% of the original asphalt performance, so that the method is used as one of the bases for determining the spreading amount of the penetration component.

C. Circular ring test

Combining with an indoor aging test, a circular ring test method is carried out on the site of a construction road section to determine the spreading amount of the penetration and solidification components, and the test steps are as follows:

(1) drawing 2-3 circles with the diameter of 15cm on the pavement to be treated by using chalk;

(2) pouring the solid components into a measuring cup, measuring out the required amount, pouring into a circular ring, uniformly coating by using a brush, recording the time and the amount, and continuing the next circular ring test;

(3) and after 15 minutes, observing the surface of the circular ring, and if a large amount of residual liquid exists on the surface, indicating that the dosage is too much, reducing the dosage, and conversely, slightly reducing the dosage, thereby determining the distribution amount of the solid permeation component.

D. Mix proportion test

The purpose of the mix proportion design is to solve the problem of compatibility of the emulsified asphalt and the aggregate. For cold-mix seal systems, the interaction of the material components is very important. Each seal system is independent, and any single composition change changes the overall mix system and can be detrimental to the road performance of the mix system. When designing the mixing proportion of the high-performance micro-surfacing mixture, factors such as use requirements, original pavement conditions, traffic volume, weather conditions and the like are fully considered, and then a construction scheme (whether layered paving is performed or not, whether rutting filling is performed or not and the like) is determined. The method considers the local climatic conditions and traffic load conditions, combines the construction purpose of the penetration wearing layer, emphasizes the waterproof performance in the design of the mix proportion, and pays attention to the shear resistance and the water damage resistance of the road surface. The main experimental detection items for the mixture proportion design are as follows:

(1) mixing test

For measuring the mixing time and the slurry state of the mixed material, in order to better approach the engineering practice, a high-temperature mixing test is carried out as necessary in consideration of the local limit air temperature.

(2) Cohesion test

The cohesion test is used for determining the initial setting and open traffic time of the mixture, and because the ambient temperature has an important influence on the cohesion value in the same system proportion, the cohesion value of the system at low temperature needs to be investigated if necessary.

(3) A wet wheel abrasion test (WTAT) determines the abrasion resistance of a mixture system after the asphalt dosage in the mixture is soaked in water at 25 ℃ for 1 hour and 6 days. To determine the minimum asphalt usage.

(4) The load wheel sand sticking test (LWT) aims at controlling the upper limit of the oil consumption of the mixture and preventing the oil flooding and the deformation of the mixture after rolling in construction.

E. Materials and equipment (1) consolidation agent (imported raw material, compounded APR consolidation agent, color required pink), as shown in table 1:

TABLE 1 technical indices of consolidating agent

2) Aggregate

The aggregate used for the penetration wearing layer is formed by rolling stone with high strength, high hardness and good wear resistance, and the rolled aggregate does not contain soil impurities, and the mud content of the aggregate is strictly controlled. The aggregate (the specification is 0-1 cm) for the asphalt mixture is preferably basalt coarse aggregate, and the grading requirement of the aggregate meets the grading requirement of technical Specifications for Highway asphalt pavement construction (JTGF40-2004) on stones of expressways and first-class highways. The coarse aggregate and the fine aggregate for the asphalt mixture of the project meet the technical requirements of the table 2.

TABLE 2 Main technical indexes of mineral aggregate for micro-surfacing

Note: 1. the test method was carried out as specified in the current road engineering aggregate test protocol (JTG E42-2005).

2. The fine aggregate is preferably machine-made sand produced by alkaline stone.

(3) Polymer modified high viscosity emulsified asphalt

The high-viscosity polymer modified emulsified asphalt for the penetration wearing layer firstly meets the technical requirements of modified emulsified asphalt in technical Specification for road asphalt pavement construction (JTG F40-2004) of Ministry of transportation, and the penetration wearing layer technology puts forward higher requirements on related technical indexes of evaporated residues of the emulsified asphalt, such as softening point and ductility, but does not meet some indexes of the specification, in consideration of the high-temperature stability and low-temperature ductility of a mixture; specific technical requirements are made on indexes such as dynamic viscosity at 60 ℃, viscosity toughness and toughness, and the indexes are shown in table 3.

TABLE 3 Polymer modified high viscosity emulsified asphalt specifications

(4) Water (W)

The mixture water must not contain harmful soluble salts, substances causing chemical reactions and other pollutants, and tap water is generally adopted.

(5) Technical requirements of slurry mixture

In order to reduce the noise of running, the mix proportion design of the asphalt mixture of the cementation wearing course is strictly carried out according to the technical specification for maintaining the asphalt pavement of the highway (JTG5142-2019), and the grading range needs to meet the technical requirements of the table 4; the technical indexes of the performance of the mixture meet the requirements of the table 5.

TABLE 4 mixture mineral aggregate gradation range

Description of the drawings: in view of the steep curve of the highway slope of the trunk line of the general state of Guizhou province, MS-3 type grading is recommended.

TABLE 5 blend Property specifications

Description of the drawings:

1. when the method is used for preventing and curing the asphalt pavement of the light traffic highway, the requirement of adhering sand quantity index can not be made.

2. The micro-surfacing mixture is not used for track filling, and the requirements of a track deformation test are not made.

3. The compatibility grade index is used as a reference index.

F. Configuration of devices

The cementation of the wearing layer must adopt special mechanical construction. The paver and the mixing tank must be of a high-power double-shaft forced stirring type, the paving trough must be provided with two rows of distributing devices, and the paver must be provided with an accurate metering system and can record or display the dosage of aggregate, emulsified asphalt and the like. The specific equipment set-up is shown in table 6.

TABLE 6 mechanical equipment outfit table

Serial number	Name (R)	Number of	Remarks for note
				1	Strong brush cleaner	1 table
2	Milling machine	1 table
				3	Emulsified asphalt workshop	1 table	When needed, the device
4	Aggregate grading sieving machine	1 table
				5	Intelligent spreading vehicle for curing agent	1 table
6	Wearing layer paver	1 table
				7	Rectangular paving groove	1 set of
8	Loading machine	1 table

G. Closed traffic

The traffic closure is strictly implemented according to the traffic organization code of urban road construction operation (GA/T900-2010), the road maintenance safety operation code (JTGH30-2015) and the code specified by local traffic governing departments.

The technical indexes of raw materials of the curing agent must meet the range specified in table 1 when the APR curing agent is sprayed. The curing agent is filled into an intelligent spreading vehicle, the spreading vehicle is calibrated according to the spreading amount calculated in advance, the spreading operation (the spreading amount range is 0.4-0.5 kg/m2) of the original road surface is carried out, and the next construction procedure can be carried out after the curing agent fully infiltrates and reacts for 20-30 minutes. The absorption time of the consolidation agent is influenced by weather, the speed is high under the condition of sunny days and sufficient sunlight, and if the weather is cloudy days, the time is prolonged, and the health preserving time is recommended to be prolonged to 40-60 minutes.

Spreading wearing layer

Preferably, a Bergkamp or VSS automatic slurry seal paver is used.

Setting out and marking: and adjusting the width of the paving box according to the width of the lane to enable the number of construction vehicle trips to be an integer. The width is set out from the curb, and the first car is marked with a running control line from the left side.

Charging: mineral aggregate, emulsified asphalt, filler, water, additive and the like meeting the requirements are respectively loaded into corresponding material boxes of the spreading machine, and the materials are generally filled completely, and the humidity of the mineral aggregate is ensured to be uniform and consistent.

Thirdly spreading

a. The spreader with the loaded materials is driven to a construction starting point, the direction control line is aligned, the spreader is placed at a working position (a traction rod is connected with a front support point), the thickness and the camber of a spreading box are adjusted, a rear rubber plate of the spreader is turned outwards, the other three-side rubber plates are turned inwards, the height and the camber of a slideway are adjusted by adjusting screws, the spreading thickness meeting the construction requirement is paved, the periphery of the spreading box is kept to be tightly attached to the original pavement, and a mop cloth is hung;

b. starting the machine after confirming the height or the opening degree of each material door, engaging a clutch of a mixing cylinder, enabling a stirring shaft to normally operate, and starting a spiral material distributor of the paving box;

c. opening each material door control switch to enable the mineral aggregate, the filler and the water to enter the mixing cylinder almost simultaneously, and ejecting the emulsion when the pre-wetted mixture is pushed to an emulsion ejection port;

d. adjusting the flow direction of the normal-temperature asphalt mixture on the diverter to ensure that the normal-temperature asphalt mixture can uniformly flow to the left and right of the paving box;

e. regulating water quantity to make the thickness of the normal temperature asphalt mixture moderate;

f. when the normal-temperature asphalt mixture is uniformly distributed in the full-width range of the paving box, starting the chassis and slowly advancing at the general advancing speed of 1.2-1.8 km/h, wherein the paving amount of the normal-temperature asphalt mixture is basically consistent with the production amount, and the volume of the normal-temperature asphalt mixture in the paving box is kept to be about 1/2 of the volume of the paving box. During construction, special attention is paid to the fact that the amount of the mixture in the paving box cannot be too large, and overflow is prevented;

g. when any material on the paver is used up, all switches are immediately closed, so that the mixture in the stirring cylinder is uniformly stirred and is conveyed into the paving box to be paved, and the forward movement is stopped;

h. when the materials are added and paved again, the materials are backed 3-4 m from the paving end point of the previous vehicle, and a section of the two sealing layers is overlapped. The raised and over-diluted mixture is scraped, so that the falling caused by inaccurate oil-water ratio during starting is avoided, and the connected stubbles are smooth and regular;

i. and lifting the paving box when the construction is finished, then opening the paver and the paving box out of the road, and cleaning the stirring cylinder and the paving box.

And (3) transverse seam treatment: usually, the transverse seam is in the form of a butt seam, and the paving vehicle is required to advance at a slightly slower speed when at a starting point, so that the phenomenon of arching caused by over-thick paving due to excessive mixture in the paving box can be avoided. After a car is paved, a shovel is used for shoveling the joint, an iron sheet is paved at the position of 0.5-1 m of the joint and is flush with the tail end of the joint, the spreading car is hung on the spreading box and is poured to the position of the joint, the spreading box is placed on the iron sheet, and after the spreading machine moves forward, the iron sheet and the mixture on the iron sheet are taken away together. This ensures a very flat and aesthetically pleasing starting point.

Longitudinal seam treatment:

the longitudinal seam is parallel to the paving direction and the driving route, and is an important aspect influencing the overall aesthetic appearance of the seal layer at the micro-surfacing. The construction lanes are constructed successively from the outside to the central separating zone, and during construction, pre-wetting water treatment is first performed in the half-width joint, and the edge of the spreading box is infinitely close to that of the lane, so that the slurry mixture has certain self-flowing flow and is favorable to the connection of the slurry mixtures in two lanes. If the lap joint is too thick or not well jointed, the rubber rake is used for scraping quickly when the lap joint is not broken, and the smoothness and the attractiveness of the joint are ensured.

Rolling and leveling: and (4) carrying out rolling and leveling treatment on the paved and joint-treated road surface by adopting a rubber-tyred road roller. The rubber-tyred road roller enhances the degree of engagement between asphalt concrete aggregate and aggregate, enhances the compactness and improves the quality of the road surface.

In the application, the APR is abbreviated as Apshalt polyethylene Rejuvenator, and in the application, the top layer of the pavement constructed according to the application is a high-performance wearing layer with the thickness of 0.9-1.1cm, and the bottom of the pavement is the original pavement (as shown in fig. 1), wherein the thickness of the APR consolidation agent reduced asphalt in the original pavement layer is generally 0.5-4.0 cm.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. It will be apparent to those skilled in the art that various changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, and the scope of protection is still within the scope of the invention.

Claims

1. The utility model provides a mountain area highway oozes APR cementation agent of wearing course maintenance which characterized in that: the APR curing agent is prepared by mixing the following raw materials in parts by weight: 40-50 parts of heavy naphthenic distilled oil, 30-35 parts of aldehyde asphalt crosslinking agent and 65-70 parts of water.

2. The APR curing agent for curing the permeable wearing course of the mountain highway according to claim 1, which is characterized in that: the heavy naphthenic distillate oil is heavy naphthenic petroleum light fraction subjected to hydrodesulfurization treatment.

3. The APR curing agent for curing the permeable wearing course of the mountain highway according to claim 1, which is characterized in that: the aldehyde asphalt crosslinking agent is prepared by performing a crosslinking reaction between a coal asphalt tetrahydrofuran extract and a crosslinking agent.

4. The construction method of the APR cementation agent for curing the permeable wearing course of the mountain highway according to any one of claims 1 to 3, which is characterized in that: the construction method comprises the following steps:

4): rolling and leveling: and (4) carrying out rolling and leveling treatment on the paved and joint-treated road surface by adopting a rubber-tyred road roller.

5. The construction method of the APR cementation agent for the maintenance of the permeability-hardened wearing course of the mountain highway according to claim 4, which is characterized in that: the sufficient infiltration reaction time of the curing agent is as follows: 20-40 min in sunny days and 40-60 min in cloudy days.

6. The construction method of the APR cementation agent for the maintenance of the permeability-hardened wearing course of the mountain highway according to claim 4, which is characterized in that: the seam treatment comprises transverse seam treatment and longitudinal seam treatment.