Cold-mixed and cold-laid super-early-strength semi-flexible pavement mixture and pavement construction method

Abstract

The invention relates to the field of novel technical material research of civil engineering, in particular to a cold-mixed and cold-laid super-early-strength semi-flexible pavement mixture which comprises the following components in parts by mass: 100 parts of a reactive cold-mixed asphalt mixture, 10-15 parts of an excitation-based grouting material and 2-4 parts of a water-based curing agent, the reactive cold-mixed asphalt mixture, the excitation-based grouting material and the water-based curing agent can be subjected to a curing reaction in pairs to form a three-dimensional network structure, so that the interface performance and the overall mechanical strength of the semi-flexible pavement mixture are comprehensively improved. By adopting the cold-mixed and cold-laid super-early-strength semi-flexible pavement mixture disclosed by the invention, rapid construction at normal temperature can be realized, the effects of energy conservation and emission reduction are achieved, and the problems of rut damage and durability of an asphalt pavement of a heavy-duty road section are effectively solved.

Description

Technical Field

[0001] The invention belongs to the research field of highway engineering technology, and specifically relates to a cold-mixed and cold-laid ultra-early-strength semi-flexible pavement mixture and a pavement construction method. Background Art

[0002] While the road traffic industry is developing rapidly, the contradiction between supply and demand of highway construction and traffic demand is also becoming increasingly severe. In particular, the number of modern transportation and logistics vehicles has increased significantly, and transportation vehicles are developing towards heavy and large directions. In addition, the traffic volume is increasing and the phenomenon of automobile overloading is very serious. Under the combined influence of heavy traffic and climatic environment, rutting disease of asphalt pavement has become the main disease of asphalt pavement. Therefore, how to effectively solve the problem of rutting disease of asphalt pavement has become the main research content of road workers.

[0003] At present, the recognized asphalt pavement rutting treatment technology at home and abroad is the semi-flexible pavement mixture technology, that is, a large-pore hot-mix asphalt mixture is first formed, and then a cement-based grouting material is poured into the large-pore hot-mix asphalt mixture as a composite pavement technology. Although this technology solves the rutting problem of flexible asphalt pavements, there are still problems of cracking and poor durability. In addition, it uses hot-mix asphalt mixture technology, which requires the asphalt to be heated to above 170°C and the aggregate to be heated to above 180°C, which does not meet the current national "dual carbon strategy" goals. At the same time, there are also problems such as long waiting time for cooling down during construction and low construction efficiency. This is why this technology has not been widely promoted and applied for decades.

[0004] At present, in order to solve the high energy consumption, high pollution and high emission problems of hot mix asphalt mixture in high temperature construction, researchers often use emulsified asphalt mixture. Although this mixture can basically meet the index requirements of dense asphalt mixture, it is difficult to guarantee the performance of semi-flexible pavement mixture with large pore interconnection and gradation, and it is not suitable for the construction of base asphalt mixture of semi-flexible asphalt pavement; In addition, in order to solve the cracking and damage problem of semi-flexible pavement, researchers often use flexible materials such as rubber powder, interface coupling agent, emulsified asphalt to prepare cement-based grouting materials. For example, patent document CN201310169974.8 discloses a semi-flexible composite pavement material, whose components are as follows by mass percentage: 65-75% of crushed stone or crushed stone mixture; 15-20% of homemade dry powder cement mortar; 3-8% of emulsified asphalt; 2-5% of mineral powder; 5-10% of water. Although it can play a certain role in resisting cracking, the grouting material is still a cement-based material, and shrinkage cracking disease cannot be avoided.

[0005] The existing semi-flexible pavement technology still fails to solve the problems of hot mix high temperature pollution and shrinkage cracking. In fact, semi-flexible pavements are often used in large traffic sections. Under the current social background, it is impossible to close traffic for a long time for construction. Therefore, it is urgent to invent a cold mix cold laying ultra-early strength semi-flexible pavement mixture and pavement construction method. Summary of the invention

[0006] Based on the problems existing in the prior art, the present invention proposes a cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture and a pavement construction method, which can realize the rapid construction of the semi-flexible pavement mixture at room temperature, achieve the effect of energy saving and emission reduction, and effectively solve the rutting disease and durability problems of asphalt pavements on heavy-loaded sections, adapting to the current trend of technological development.

[0007] The technical solution adopted by the present invention is:

[0008] A cold-mixed and cold-laid ultra-early-strength semi-flexible pavement mixture, comprising the following components in parts by mass:

[0009] 100 parts of reactive cold mix asphalt;

[0010] 10-15 parts of excitation base grouting material;

[0011] 2-4 parts of water-based curing agent;

[0012] The water-based curing agent and the excitation-based grouting material are mixed in proportion to obtain a high-fluidity liquid grouting material, and the liquid grouting material is poured into the reactive cold-mix asphalt mixture to obtain a cold-mix cold-paved ultra-early-strength semi-flexible pavement mixture.

[0013] Furthermore, the reactive cold mix asphalt mixture comprises a reactive base asphalt, a interconnected graded aggregate and a waterborne epoxy resin.

[0014] Furthermore, the reactive cold mix asphalt mixture comprises the following components in parts by weight:

[0015] 5-8 parts of reactive base asphalt;

[0016] 87-94 parts of connected graded aggregate;

[0017] 1-5 parts of water-based epoxy resin.

[0018] Furthermore, the reactive base asphalt includes one or more of 70# road petroleum asphalt, SBS modified asphalt, biodiesel, and epoxidized soybean oil; when the reactive base asphalt is composed of 70# road petroleum asphalt, biodiesel and epoxidized soybean oil, the mass fraction of 70# road petroleum asphalt is 50%, the mass fraction of biodiesel is 30% and the mass fraction of epoxidized soybean oil is 20%; when the reactive base asphalt is composed of SBS modified asphalt and biodiesel, the mass fraction of SBS modified asphalt is 70%, and the mass fraction of biodiesel is 30%.

[0019] Furthermore, the interconnected graded aggregate is a interconnected graded 13 mixture, a interconnected graded 16 mixture or a interconnected graded 20 mixture, wherein the key control sieve hole of the interconnected graded aggregate is 4.75 mm, and the pass rate of the key control sieve hole of 4.75 mm is controlled between 9.5% and 11.5%.

[0020] Furthermore, the excited-base grouting material comprises fly ash, slag powder, recycled micro powder, ethylenediamine, triethylenetetramine, low molecular weight polyamide and dimethylaniline.

[0021] Furthermore, the excitation-based grouting material comprises the following components in parts by mass:

[0022] 5-10 parts of fly ash;

[0023] 5-10 parts of slag powder;

[0024] 3-5 parts of recycled micro powder;

[0025] 1-2 parts of ethylenediamine;

[0026] 1-2 parts of triethylenetetramine;

[0027] 2-3 parts of low molecular weight polyamide;

[0028] 1-3 parts of dimethylaniline.

[0029] Furthermore, the water-based curing agent includes water, sodium silicate, sodium hydroxide, calcium oxide and butyltin dilaurate.

[0030] Furthermore, the water-based curing agent comprises the following components in parts by mass:

[0031] 15-25 parts water;

[0032] Sodium silicate 1-5 parts;

[0033] 0.5-4 parts of sodium hydroxide;

[0034] Calcium oxide 0.5-3 parts;

[0035] 1-3 parts of butyltin dilaurate.

[0036] The method for pavement construction using the cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture comprises the following steps:

[0037] S1. Prepare a reactive cold-mix asphalt mixture: first, one or more of 70# road petroleum asphalt, SBS modified asphalt, biodiesel and epoxidized soybean oil are stirred in an asphalt tank at 140°C-160°C in proportion to prepare a reactive base asphalt, and connected graded aggregates are provided according to key sieve holes, and the reactive base asphalt, the connected graded aggregates and water-based epoxy resin are mixed in a mixing plant in proportion at room temperature to obtain a reactive cold-mix asphalt mixture;

[0038] S2. Forming reactive cold mix asphalt mixture: transport and spread the mixed reactive cold mix asphalt mixture to the on-site construction pavement, use a steel wheel roller to roll it 2-4 times, and test its connected porosity to be 15%-20%, Marshall stability not less than 5kN, and Kentburg loss value not more than 20%, which meets the requirements, and use sealant to do edge sealing work;

[0039] S3. Preparation of high-fluidity liquid grouting material: using on-site mixing equipment to prepare high-fluidity liquid grouting material according to the proportion of water-based curing agent and excitation-based grouting material; the excitation-based grouting material includes fly ash, slag powder, recycled micropowder, ethylenediamine, triethylenetetramine, low molecular weight polyamide and dimethylaniline; the water-based curing agent includes water, sodium silicate, sodium hydroxide, calcium oxide and butyltin dilaurate;

[0040] S4. Grouting: Pump the high-fluidity liquid grouting material onto the formed reactive cold-mix asphalt mixture, and the grouting material will automatically penetrate into the reactive cold-mix asphalt mixture due to its high fluidity until it is fully filled and no longer seeps;

[0041] S5. Maintain and inspect the construction quality. After curing for 2 hours under natural conditions, carry out core sampling inspection. If the injection saturation is not less than 90% and the Marshall stability of the core sampling is not less than 20KN after 2 hours, the construction is completed.

[0042] The beneficial effects produced by the present invention are as follows:

[0043] (1) The cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture and pavement construction method of the present invention are a new low-carbon and environmentally friendly road construction material and technology. It does not require heating asphalt and aggregate to above 170°C and 180°C, and can achieve construction at room temperature, greatly reducing carbon emissions during road maintenance;

[0044] (2) It effectively solves the cracking and durability problems of semi-flexible pavement mixtures. Through the three-dimensional network structure formed by the two-by-two curing reaction of the reactive cold-mix asphalt mixture and the activated-base grouting material and the water-based curing agent, and through the addition, grafting, chain extension and end-capping treatment of the hybrid interface, the crack resistance of the semi-flexible pavement mixture is significantly improved, which is 1.5 times that of ordinary semi-flexible pavements, thereby extending its service life;

[0045] (3) It effectively solves the problem of low construction efficiency of semi-flexible pavement mixtures and can reduce the construction waiting time for cooling down by 5-8 hours. The construction efficiency is twice that of conventional semi-flexible pavement mixtures and has super early strength performance. The 2h Marshall stability of the semi-flexible pavement is more than 30KN, and the rutting dynamic stability is more than 30,000 times / mm. It can realize rapid opening of traffic while effectively solving the rutting problem of the road surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is a rendering of the interface microstructure of the cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture in Example 6 of the present invention. DETAILED DESCRIPTION

[0047] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be pointed out that the embodiments described below are intended to facilitate the understanding of the present invention and do not have any limiting effect on the present invention.

[0048] Example 1

[0049] The present invention provides a cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture, comprising the reactive cold-mixed asphalt mixture, wherein the reactive cold-mixed asphalt mixture comprises a reactive base asphalt, a connected graded aggregate, and a waterborne epoxy resin. The components used by mass are: 5 parts of reactive base asphalt, 93 parts of connected graded aggregate, and 2 parts of waterborne epoxy resin.

[0050] In order to prepare a reactive base asphalt, the reactive base asphalt includes 70# road petroleum asphalt, biodiesel and epoxidized soybean oil, wherein the mass fraction of the 70# road petroleum asphalt is 50%, the mass fraction of the biodiesel is 30%, and the mass fraction of the epoxidized soybean oil is 20%. The material components are weighed according to the proportion, the 70# road petroleum asphalt is heated to 140°C, and then the 70# road petroleum asphalt is stirred by a stirring device while the proportion of biodiesel and epoxidized soybean oil are slowly added until a uniform reactive base asphalt is obtained after stirring for 1 hour.

[0051] In order to prepare a connected graded 13 mixture, the pass rate of the key sieve hole is controlled to be 11.5% at 4.75 mm. The proportion of the connected graded 13 mixture obtained by adjusting the grading is shown in Table 1.

[0052] Table 1 Mixing ratio of connected grade 13 mixture

[0053]

[0054]

[0055] In order to prepare a reactive cold-mix asphalt mixture, 5 parts of the reactive base asphalt prepared by the above scheme, 93 parts of the interconnected graded aggregate and 2 parts of the water-based epoxy resin were added into a mixing tank and stirred at room temperature. The interconnected graded aggregate was first dry-mixed, then the reactive base asphalt was added for wet mixing, and finally the water-based epoxy resin was added and stirred evenly to further improve the bonding strength.

[0056] The stirred reactive cold mix asphalt mixture was formed into Marshall specimens using the Marshall molding method. Both sides were compacted 50 times. Then, the connected porosity, Marshall stability and Kentburg loss value were measured. The results are shown in Table 2.

[0057] Table 2 Test results of reactive cold mix asphalt mixture performance

[0058] Detection indicators Test results Index requirements Connected porosity 18.3％ 15％-20％ Marshall stability 6.9KN ≥5KN Kentucky Fort Loss 13.2％ ≤20％

[0059] It can be found that all performance tests of the prepared reactive cold mix asphalt mixture can meet the technical index requirements. The obtained connected porosity is 18.3%, which can ensure the smooth pouring of the grouting material. The obtained Marshall stability is 6.9KN and the Kentburgh loss value is 13.2%, which well guarantees the performance stability of the reactive cold mix asphalt mixture before grouting.

[0060] Example 2

[0061] The present invention provides a cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture, comprising the reactive cold-mixed asphalt mixture, wherein the reactive cold-mixed asphalt mixture comprises a reactive base asphalt, a connected graded aggregate, and a waterborne epoxy resin. The components used by mass are: 5 parts of reactive base asphalt, 87 parts of connected graded aggregate, and 1 part of waterborne epoxy resin.

[0062] In order to prepare a reactive base asphalt, the reactive base asphalt includes 70# road petroleum asphalt, biodiesel and epoxidized soybean oil, wherein the mass fraction of the 70# road petroleum asphalt is 50%, the mass fraction of the biodiesel is 30%, and the mass fraction of the epoxidized soybean oil is 20%. The material components are weighed according to the proportion, the 70# road petroleum asphalt is heated to 145°C, and then the 70# road petroleum asphalt is stirred by a stirring device while the proportion of biodiesel and epoxidized soybean oil are slowly added until a uniform reactive base asphalt is obtained after stirring for 1 hour.

[0063] In order to prepare a connected graded 16 mixture, the pass rate of the key sieve hole is controlled to be 9.5% at 4.75 mm. The proportion of the connected graded 16 mixture obtained by adjusting the grading is shown in Table 3.

[0064] Table 3 Proportion of the mixture with connected grade 16

[0065]

[0066] In order to prepare a reactive cold-mix asphalt mixture, 5 parts of the reactive base asphalt prepared by the above scheme, 87 parts of the interconnected graded aggregate and 1 part of the water-based epoxy resin were added into a mixing tank and stirred at room temperature. The interconnected graded aggregate was first dry-mixed, then the reactive base asphalt was added for wet mixing, and finally the water-based epoxy resin was added and stirred evenly to further improve the bonding strength.

[0067] The stirred reactive cold mix asphalt mixture was formed into Marshall specimens using the Marshall molding method. Both sides were compacted 50 times. Then, the connected porosity, Marshall stability and Kentburg loss value were measured. The results are shown in Table 4.

[0068] Table 4 Test results of reactive cold mix asphalt mixture performance

[0069] Detection indicators Test results Index requirements Connected porosity 18.9％ 15％-20％ Marshall stability 5.8KN ≥5KN Kentucky Fort Loss 15.7％ ≤20％

[0070] It can be found that all performance tests of the prepared reactive cold mix asphalt mixture can meet the technical index requirements. The obtained connected porosity is 18.9%, which can ensure the smooth pouring of the grouting material. The obtained Marshall stability is 5.8KN and the Kentburgh loss value is 15.7%, which well guarantees the performance stability of the reactive cold mix asphalt mixture before grouting.

[0071] Example 3

[0072] The present invention provides a cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture, comprising the reactive cold-mixed asphalt mixture, wherein the reactive cold-mixed asphalt mixture comprises a reactive base asphalt, a connected graded aggregate, and a water-based epoxy resin. The components used by mass are: 8 parts of reactive base asphalt, 94 parts of connected graded aggregate, and 5 parts of water-based epoxy resin.

[0073] In order to prepare a reactive base asphalt, the reactive base asphalt includes 70# road petroleum asphalt, biodiesel and epoxidized soybean oil, wherein the mass fraction of the 70# road petroleum asphalt is 50%, the mass fraction of the biodiesel is 30%, and the mass fraction of the epoxidized soybean oil is 20%. The material components are weighed according to the proportion, the 70# road petroleum asphalt is heated to 160°C, and then the 70# road petroleum asphalt is stirred by a stirring device while the proportion of biodiesel and epoxidized soybean oil are slowly added until a uniform reactive base asphalt is obtained after stirring for 1 hour.

[0074] In order to prepare a connected graded 20 mixture, the pass rate of the key sieve hole is controlled to be 4.75 mm and is 9.8%. The proportion of the connected graded 20 mixture obtained by adjusting the grading is shown in Table 5.

[0075] Table 5 Mixing ratio of connected graded 20 mixture

[0076]

[0077] In order to prepare a reactive cold-mix asphalt mixture, 8 parts of the reactive base asphalt prepared by the above scheme, 94 parts of the interconnected graded aggregate and 5 parts of the water-based epoxy resin were added into a mixing tank and stirred at room temperature. The interconnected graded aggregate was first dry-mixed, then the reactive base asphalt was added for wet mixing, and finally the water-based epoxy resin was added and stirred evenly to further improve the bonding strength.

[0078] The stirred reactive cold mix asphalt mixture was formed into Marshall specimens using the Marshall molding method. Both sides were compacted 50 times. Then, the connected porosity, Marshall stability and Kentburg loss value were measured. The results are shown in Table 6.

[0079] Table 6 Test results of reactive cold mix asphalt mixture performance

[0080] Detection indicators Test results Index requirements Connected porosity 19.7％ 15％-20％ Marshall stability 7.3KN ≥5KN Kentucky Fort Loss 11.6％ ≤20％

[0081] It can be found that all performance tests of the prepared reactive cold mix asphalt mixture can meet the technical index requirements. The obtained connected porosity is 19.7%, which can ensure the smooth pouring of the grouting material. The obtained Marshall stability is 7.3KN and the Kentburgh loss value is 11.6%, which well guarantees the performance stability of the reactive cold mix asphalt mixture before grouting.

[0082] Example 4

[0083] The cold-mixed and cold-laid ultra-early-strength semi-flexible pavement mixture proposed by the present invention also includes the excited-based grouting material and a water-based curing agent. The excited-based grouting material includes fly ash, slag powder, recycled micropowder, ethylenediamine, triethylenetetramine, low molecular weight polyamide and dimethylaniline, and the water-based curing agent includes water, sodium silicate, sodium hydroxide, calcium oxide and butyltin dilaurate.

[0084] In order to prepare the excitation-based grouting material, the components used by mass are: 5 parts of fly ash, 5 parts of slag powder, 3 parts of recycled micro powder, 1 part of ethylenediamine, 1 part of triethylenetetramine, 2 parts of low molecular weight polyamide and 1 part of dimethylaniline. The corresponding proportions of the components are added to the stirring bar and stirred for 10 minutes to obtain a uniform excitation-based grouting material.

[0085] In order to prepare a water-based curing agent, the components used by mass are: 20 parts of water, 2 parts of sodium silicate, 1 part of sodium hydroxide, 1 part of calcium oxide and 1.5 parts of butyltin dilaurate. The corresponding proportions of each component material are added to 20 parts of water in sequence, and stirred and dissolved at room temperature for 10 minutes to obtain a water-based curing agent.

[0086] 2 parts of the water-based curing agent and 10 parts of the excited-base grouting material are stirred in the proportion, with the stirring rate of the mixer being 3000 rpm, and stirred for 5 minutes to obtain a high-fluidity liquid grouting material. The performance results of the high-fluidity liquid grouting material are tested and shown in Table 7.

[0087] Table 7 Performance test results of high fluidity liquid grouting material

[0088] Detection indicators Test results Index requirements Fluidity 489mm 400-500mm 2h compressive strength 29.4MPa ≥20MPa 2h flexural strength 5.9MPa /

[0089] It can be found that various performance tests of the prepared high-fluidity liquid grouting material can meet the requirements of technical indicators. The obtained fluidity is 489mm, which can ensure the high fluidity of the grouting material. It can be poured into the reactive cold-mix asphalt mixture without the need for external pressure. The obtained 2h compressive strength is 29.4MPa, which can ensure sufficient bearing capacity of the semi-flexible road, and the traffic can be opened 2 hours after the construction is completed.

[0090] Example 5

[0091] The cold-mixed and cold-laid ultra-early-strength semi-flexible pavement mixture proposed by the present invention also includes the excited-based grouting material and a water-based curing agent. The excited-based grouting material includes fly ash, slag powder, recycled micropowder, ethylenediamine, triethylenetetramine, low molecular weight polyamide and dimethylaniline, and the water-based curing agent includes water, sodium silicate, sodium hydroxide, calcium oxide and butyltin dilaurate.

[0092] In order to prepare the excitation-based grouting material, the components used by mass are: 10 parts of fly ash, 10 parts of slag powder, 5 parts of recycled micro powder, 2 parts of ethylenediamine, 2 parts of triethylenetetramine, 3 parts of low molecular weight polyamide and 3 parts of dimethylaniline. The corresponding proportions of the components are added to the stirring bar and stirred for 10 minutes to obtain a uniform excitation-based grouting material.

[0093] In order to prepare a water-based curing agent, the components used by mass are: 15 parts of water, 1 part of sodium silicate, 0.5 parts of sodium hydroxide, 0.5 parts of calcium oxide and 1 part of butyltin dilaurate. The corresponding proportions of each component material are added to 15 parts of water in sequence, and stirred and dissolved at room temperature for 10 minutes to obtain a water-based curing agent.

[0094] 4 parts of the water-based curing agent and 15 parts of the excited-base grouting material are stirred in the proportion, with the stirring rate of the mixer being 3000 rpm for 5 minutes to obtain a high-fluidity liquid grouting material. The performance results of the high-fluidity liquid grouting material are tested and shown in Table 8.

[0095] Table 8 Performance test results of high fluidity liquid grouting material

[0096] Detection indicators Test results Index requirements Fluidity 419mm 400-500mm 2h compressive strength 23.2MPa ≥20MPa 2h flexural strength 4.7MPa /

[0097] It can be found that various performance tests of the prepared high-fluidity liquid grouting material can meet the requirements of technical indicators. The obtained fluidity is 419mm, which can ensure the high fluidity of the grouting material. It can be poured into the reactive cold-mix asphalt mixture without the need for external pressure. The obtained 2h compressive strength is 23.2MPa, which can ensure sufficient bearing capacity of the semi-flexible road, and the traffic can be opened 2 hours after the construction is completed.

[0098] Example 6

[0099] The present invention proposes a cold-mixed cold-laid ultra-early-strength semi-flexible pavement mixture, which comprises the following components by mass: 100 parts of reactive cold-mixed asphalt mixture, 12 parts of excited base grouting material and 3 parts of water-based curing agent. In order to prepare the reactive cold-mixed asphalt mixture, it is necessary to prepare reactive base asphalt, interconnected graded aggregate and water-based epoxy resin respectively. The components include the following components by mass: 7 parts of reactive base asphalt, 89 parts of interconnected graded aggregate and 4 parts of water-based epoxy resin.

[0100] In order to prepare the reactive base asphalt, SBS modified asphalt and biodiesel are used, wherein the mass fraction of the SBS modified asphalt is 70% and the mass fraction of the biodiesel is 30%. The material components are weighed according to the proportion, the SBS modified asphalt is heated to 160°C, and then the SBS modified asphalt is stirred by a stirring device while the proportion of biodiesel is slowly added until a uniform reactive base asphalt is obtained after stirring for 1 hour.

[0101] In order to prepare a connected graded 20 mixture, the pass rate of the key sieve hole is controlled to be 9.8% at 4.75 mm. The mix ratio of the connected graded 20 mixture obtained by adjusting the grading is shown in Table 9.

[0102] Table 9 Proportions of connected graded 20 mixtures

[0103]

[0104]

[0105] In order to prepare a reactive cold mix asphalt mixture, 7 parts of the reactive base asphalt prepared in the above scheme, 89 parts of the interconnected graded aggregate and 4 parts of the waterborne epoxy resin were added into a mixing tank and stirred at room temperature. The interconnected graded aggregate was first dry-mixed, then the reactive base asphalt was added for wet mixing, and finally the waterborne epoxy resin was added and stirred evenly.

[0106] The stirred reactive cold mix asphalt mixture was formed into Marshall specimens using the Marshall molding method. Both sides were compacted 50 times each. Then, the connected porosity, Marshall stability and Kentburg loss value were measured respectively. The results are shown in Table 10.

[0107] Table 10 Test results of reactive cold mix asphalt mixture performance

[0108] Detection indicators Test results Technical requirements Connected porosity 19.2％ 15％-20％ Marshall stability 8.3KN ≥5KN Kentucky Fort Loss 9.1％ ≤20％

[0109] It can be found that all performance tests of the prepared reactive cold mix asphalt mixture can meet the technical index requirements, and all preparations are excellent.

[0110] In order to prepare the excitation-based grouting material, the components used by mass are: 8 parts of fly ash, 8 parts of slag powder, 4 parts of recycled micro powder, 1.5 parts of ethylenediamine, 1.5 parts of triethylenetetramine, 2.5 parts of low molecular weight polyamide and 2 parts of dimethylaniline. The corresponding proportions of the components are added to the stirring bar and stirred for 10 minutes to obtain a uniform excitation-based grouting material.

[0111] In order to prepare a water-based curing agent, the components used by mass fraction are: 25 parts of water, 5 parts of sodium silicate, 4 parts of sodium hydroxide, 3 parts of calcium oxide and 3 parts of butyltin dilaurate. The corresponding proportions of each component material are added to 25 parts of water in turn, and the water-based curing agent is obtained by stirring and dissolving at room temperature for 10 minutes.

[0112] 3 parts of the water-based curing agent and 12 parts of the excited-base grouting material are stirred in the stated proportions at a stirring rate of 3000 rpm for 7 minutes to obtain a high-fluidity liquid grouting material. The performance results of the high-fluidity liquid grouting material are tested and are shown in Table 11.

[0113] Table 11 Performance test results of high fluidity liquid grouting material

[0114] Detection indicators Test results Technical requirements Fluidity 416mm 400-500mm 2h compressive strength 34.2MPa ≥20MPa 2h flexural strength 7.5MPa /

[0115] It can be found that the performance test results of the obtained high-fluidity liquid grouting materials all meet the index requirements. In order to further verify the performance of the cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture, the semi-flexible pavement mixture was prepared by mixing 100 parts of reactive cold-mix asphalt mixture and 15 parts of high-fluidity liquid grouting materials. First, the Marshall specimens and rutting plates of the reactive cold-mix asphalt mixture were formed, and then the high-fluidity liquid grouting material was poured. After curing for 2 hours under natural conditions, the mechanical properties were demolded and tested. The mechanical properties test results of the obtained cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture are shown in Table 12.

[0116] Table 12 Test results of mechanical properties of cold-mixed and cold-paved ultra-early-strength semi-flexible pavement mixture

[0117] Detection indicators Detection indicators Detection indicators Filling fullness 96.3％ ≥90％ Marshall stability 42.5KN ≥30KN Kentucky Fortress Dispersion Loss Rate 0.5％ ≤20％ Rutting stability 48539 times / mm ≥30000 times / mm Low temperature beam bending tensile strength 7468με ≥2500με

[0118] It can be seen that the cold-mixed cold-laid super-early-strength semi-flexible pavement mixture has super-early-strength performance, and the 2h Marshall stability is as high as 42.5KN, which can reduce the maintenance construction time; it also has super strong anti-rutting performance, and the dynamic stability is as high as 48539 times / mm, which can effectively solve the rutting problem of asphalt pavement. In addition, the anti-cracking performance of the cold-mixed cold-laid super-early-strength semi-flexible pavement mixture is significantly improved. Figure 1 From the interface microstructure shown, it can be found that the three-dimensional network structure formed by the two-way curing reaction of the reactive cold mix asphalt mixture and the excited base filling and the water-based curing agent forms a stable structure through addition grafting at the hybrid interface.

[0119] In order to verify the road performance of cold-mixed and cold-laid ultra-early-strength semi-flexible pavement mixture, it is applied based on a physical engineering test section. The test section is located in the main traffic artery in the city, with heavy traffic volume and tight maintenance and construction time. It is also located in the urban road, and it is necessary to avoid the impact of asphalt fumes, environmental pollution and traffic congestion caused by high-temperature construction on citizens' lives.

[0120] The cold-mixed and cold-laid ultra-early-strength semi-flexible pavement mixture of the present invention effectively avoids the construction difficulties of major urban traffic arteries.

[0121] First, a reactive cold-mix asphalt mixture is prepared: 70% by mass of SBS modified asphalt and 30% by mass of biodiesel are stirred in an asphalt tank at 160°C in proportion to prepare a reactive base asphalt, and a connected gradation 20 mixture is prepared according to a pass rate of 9.8% at a key sieve hole of 4.75 mm, and 7 parts of the reactive base asphalt, 89 parts of the connected gradation 20 mixture and 4 parts of waterborne epoxy resin are mixed in a mixing plant in proportion to obtain a reactive cold-mix asphalt mixture;

[0122] Secondly, forming reactive cold mix asphalt mixture: transport and spread the mixed reactive cold mix asphalt mixture to the on-site construction pavement, use a steel wheel roller to roll it three times, and test its connected porosity to be 18.7%, Marshall stability to be 8.5kN, and Kentburgh loss value to be 9.6%, and use sealant to seal the edges;

[0123] Then, prepare high-fluidity liquid grouting material: use on-site mixing equipment to mix 3 parts of the water-based curing agent and 12 parts of the excitation-based grouting material in a ratio of 1: 8 parts of fly ash, 8 parts of slag powder, 4 parts of recycled micro powder, 1.5 parts of ethylenediamine, 1.5 parts of triethylenetetramine, 2.5 parts of low molecular weight polyamide and 2 parts of dimethylaniline. The water-based curing agent is divided into 25 parts of water, 5 parts of sodium silicate, 4 parts of sodium hydroxide, 3 parts of calcium oxide and 3 parts of butyltin dilaurate;

[0124] Next, pour the grouting material: pump the high-fluidity liquid grouting material onto the formed reactive cold-mix asphalt mixture, and the grouting material will automatically penetrate into the reactive cold-mix asphalt mixture due to its high fluidity until it is fully poured and no longer seeps;

[0125] Finally, core sampling was carried out after curing for 2 hours under natural conditions. The performance results of the cold-mixed and cold-laid ultra-early strength semi-flexible pavement mixture are shown in Table 13.

[0126] Table 13 Performance test results of cold-mixed cold-laid ultra-early-strength semi-flexible pavement mixture

[0127] Detection indicators Test results Technical requirements Filling fullness 94.7％ ≥90％ Marshall stability 38.5KN ≥30KN Kentucky Fortress Dispersion Loss Rate 0.7％ ≤20％ Rutting stability 52169 times / mm ≥30000 times / mm Low temperature beam bending tensile strength 7348με ≥2500με Flatness 0.87mm ≤2 / mm Friction coefficient 58.4 / mm ≥54 / mm Construction Depth 0.72 / mm ≥0.5 / mm

[0128] Judging from the implementation effect of the test section project, the cold-mixed and cold-laid ultra-early-strength semi-flexible pavement mixture of the present invention does not require heating of asphalt and aggregate to above 170°C and 180°C, and can be constructed at room temperature, which greatly reduces the high energy consumption, high pollution and high emission problems in the road maintenance process, and reduces the environmental pollution of construction and the impact on the lives of surrounding citizens; in addition, it effectively solves the problem of low construction efficiency of semi-flexible pavement mixtures, can reduce the construction waiting time for cooling down by 5-8 hours, and the construction efficiency is twice that of conventional semi-flexible pavement mixtures, and has ultra-early strength performance. The 2h Marshall stability of the semi-flexible pavement is more than 30KN, and the rutting dynamic stability is more than 30,000 times / mm. It can realize rapid opening of traffic while effectively solving the rutting disease problem of the road surface, with significant economic and social benefits.

[0129] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture, characterized in that: The composition includes the following components in parts by weight: 100 parts of reactive cold mix asphalt; 10-15 parts of excitation base grouting material; 2-4 parts of water-based curing agent; The water-based curing agent and the excitation-based grouting material are mixed in proportion to obtain a high-fluidity liquid grouting material, and the liquid grouting material is poured into the reactive cold-mix asphalt mixture to obtain a cold-mix cold-paved ultra-early-strength semi-flexible pavement mixture.

2. The cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture according to claim 1, characterized in that: The reactive cold-mix asphalt mixture comprises reactive base asphalt, interconnected graded aggregate and waterborne epoxy resin.

3. The cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture according to claim 2, characterized in that: The reactive cold mix asphalt mixture comprises the following components in parts by weight: 5-8 parts of reactive base asphalt; 87-94 parts of connected graded aggregate; 1-5 parts of water-based epoxy resin.

4. The cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture according to claim 2, characterized in that: The reactive base asphalt comprises one or more of 70# road petroleum asphalt, SBS modified asphalt, biodiesel, and epoxidized soybean oil; when the reactive base asphalt is composed of 70# road petroleum asphalt, biodiesel, and epoxidized soybean oil, the mass fraction of 70# road petroleum asphalt is 50%, the mass fraction of biodiesel is 30%, and the mass fraction of epoxidized soybean oil is 20%; when the reactive base asphalt is composed of SBS modified asphalt and biodiesel, the mass fraction of SBS modified asphalt is 70%, and the mass fraction of biodiesel is 30%.

5. The cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture according to claim 2, characterized in that: The interconnected graded aggregate is a interconnected graded 13 mixture, a interconnected graded 16 mixture or a interconnected graded 20 mixture, wherein the key control sieve hole of the interconnected graded aggregate is 4.75 mm, and the pass rate of the key control sieve hole of 4.75 mm is controlled between 9.5% and 11.5%.

6. The cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture according to claim 1, characterized in that: The excitation-based grouting material comprises fly ash, slag powder, recycled micro powder, ethylenediamine, triethylenetetramine, low molecular weight polyamide and dimethylaniline.

7. The cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture according to claim 6, characterized in that: The excitation-based grouting material comprises the following components in parts by mass: 5-10 parts of fly ash; 5-10 parts of slag powder; 3-5 parts of recycled micro powder; 1-2 parts of ethylenediamine; 1-2 parts of triethylenetetramine; 2-3 parts of low molecular weight polyamide; 1-3 parts of dimethylaniline.

8. The cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture according to claim 1, characterized in that: The water-based curing agent comprises water, sodium silicate, sodium hydroxide, calcium oxide and butyltin dilaurate.

9. The cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture according to claim 8, characterized in that: The water-based curing agent comprises the following components in parts by mass: 15-25 parts water; Sodium silicate 1-5 parts; 0.5-4 parts of sodium hydroxide; Calcium oxide 0.5-3 parts; 1-3 parts of butyltin dilaurate.

10. A method for pavement construction using a cold-mixed, cold-laid, ultra-early-strength semi-flexible pavement mixture as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Prepare a reactive cold-mix asphalt mixture: first, one or more of 70# road petroleum asphalt, SBS modified asphalt, biodiesel and epoxidized soybean oil are stirred in an asphalt tank at 140°C-160°C in proportion to prepare a reactive base asphalt, and connected graded aggregates are provided according to key sieve holes, and the reactive base asphalt, the connected graded aggregates and water-based epoxy resin are mixed in a mixing plant in proportion at room temperature to obtain a reactive cold-mix asphalt mixture; S2. Forming reactive cold mix asphalt mixture: transport and spread the mixed reactive cold mix asphalt mixture to the on-site construction pavement, use a steel wheel roller to roll it 2-4 times, and test its connected porosity to be 15%-20%, Marshall stability not less than 5kN, and Kentburg loss value not more than 20%, which meets the requirements, and use sealant to do edge sealing work; S3. Preparation of high-fluidity liquid grouting material: using on-site mixing equipment to prepare high-fluidity liquid grouting material according to the proportion of water-based curing agent and excitation-based grouting material; the excitation-based grouting material includes fly ash, slag powder, recycled micropowder, ethylenediamine, triethylenetetramine, low molecular weight polyamide and dimethylaniline; the water-based curing agent includes water, sodium silicate, sodium hydroxide, calcium oxide and butyltin dilaurate; S4. Grouting: Pump the high-fluidity liquid grouting material onto the formed reactive cold-mix asphalt mixture, and the grouting material will automatically penetrate into the reactive cold-mix asphalt mixture due to its high fluidity until it is fully filled and no longer seeps; S5. Maintain and inspect the construction quality. After curing for 2 hours under natural conditions, carry out core sampling inspection. If the injection saturation is not less than 90% and the Marshall stability of the core sampling is not less than 20KN after 2 hours, the construction is completed.

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