Construction method and spraying system for cement-stabilized base pavement with asphalt surface course

Abstract

The invention relates to the technical field of highway construction, in particular to a construction method and a spraying system for a water-stabilized base pavement with an asphalt surface layer, and the construction method comprises the following steps: step 1, pre-treating a lower base layer; 2, paving the water-stable base layer on the surface of the lower base layer subjected to pretreatment, and synchronously spraying prime coat oil on the surface of the water-stable base layer formed by the paving; 3, road surface rolling operation is carried out on the water-stable base layer sprayed with the prime coat oil, and asphalt surface layer spraying operation is carried out on the road surface formed through rolling within 24 h after rolling operation is completed; and step 4, performing curing treatment on the water-stable base pavement sprayed by the asphalt surface layer to obtain the water-stable base pavement with the asphalt surface layer. The method not only can solve the problems of difficult penetration and insufficient penetration depth of the prime coat oil, but also can improve the bonding performance of the asphalt surface layer, and is beneficial to prolonging the service life of the pavement.

Description

Technical Field

[0001] The invention relates to the technical field of highway construction, and in particular to a construction method and a spraying system for a water-stable base road surface with an asphalt surface layer. Background Art

[0002] At present, cement-stabilized granular base (referred to as water-stabilized base) is still the load-bearing base used in large quantities in high-grade highways. The top surface of the load-bearing base is mostly paved with asphalt surface layer. At the same time, the "Technical Specifications for Highway Asphalt Pavement Construction" requires that "all types of base layers of asphalt pavement must be sprayed with penetration oil, and the asphalt layer can only be paved after the penetration oil has completely penetrated into the base layer." Among them, the specifications also require that the penetration depth of the penetration oil of the semi-rigid base layer should not be less than 5mm. Therefore, it can be seen that the penetration oil plays a vital role in the commonly used pavement structure.

[0003] However, in the related technology, the compaction degree of the water-stable base layer can reach more than 98% after paving and rolling, and the surface of the semi-rigid base layer is very dense. As the age of the semi-rigid base layer increases, the hydration reaction gradually proceeds, and the base layer becomes denser. At this time, the penetration depth of the permeable oil is difficult to meet the design and specification requirements. The permeable oil that cannot penetrate forms an excess oil film on the surface of the base layer, which has an adverse effect on the adhesion of the base layer to the surface. When the traditional permeable oil spreading cannot ensure that the semi-rigid base layer and the asphalt layer form a complete whole, the poor contact state between the layers will form the weakest link, and the stress will be concentrated first under the load. After reaching the maximum stress, the contact state between the layers will be destroyed.

[0004] Therefore, in view of the above shortcomings, the present invention is specially proposed. Summary of the invention

[0005] The purpose of the present invention is to provide a construction method and construction equipment for a water-stable base pavement with an asphalt surface layer, so as to solve the problem in the prior art that penetrating oil cannot stably connect the water-stable base and the asphalt surface layer.

[0006] A first aspect of the present invention provides a construction method for a water-stable base pavement having an asphalt surface layer, comprising:

[0007] Step 1: Pre-treat the base layer;

[0008] Step 2: Perform paving operations on the surface of the pre-treated lower base layer, and simultaneously perform a permeable oil spraying operation on the surface of the water-stable base layer formed by the paving operation;

[0009] Step 3: Perform pavement rolling on the water-stable base layer sprayed with penetration oil, and perform asphalt surface spraying on the compacted pavement within 24 hours after the pavement rolling operation is completed;

[0010] Step 4: Perform curing treatment on the water-stable base pavement sprayed with the asphalt surface layer to obtain a water-stable base pavement with an asphalt surface layer.

[0011] The construction method provided by the present invention may also have the following additional technical features:

[0012] In a specific embodiment of the present invention, the pre-treatment in step 1 includes cleaning the lower base, and spreading cement slurry or cement on the lower base after cleaning.

[0013] In a specific embodiment of the present invention, the penetrating oil in step 2 and the asphalt surface sprayed in step 3 are both fast-cracking emulsified asphalt; and / or in step 2, the spraying amount of the emulsified asphalt is 1.5±0.1L / m2, and in step 3, the spraying amount of the emulsified asphalt is 1±0.1L / m2.

[0014] In a specific embodiment of the present invention, the road surface rolling operation in step 3 includes:

[0015] Use a double steel wheel roller to perform static compaction once, with a compaction speed of 1.5km / h to 2km / h;

[0016] Use a vibratory roller to roll once, with a rolling speed of 2 to 2.5 km / h;

[0017] Use a rubber-wheel roller to roll the road twice at a speed of 2 to 2.5 km / h.

[0018] In a specific embodiment of the present invention, the environmental conditions for the paving operation of the water-stable base layer, the spraying operation of the penetration oil and the spraying operation of the asphalt surface layer are non-rainy weather with a temperature not less than 10°C.

[0019] In a specific embodiment of the present invention, the road surface rolling operation starts immediately after the paving operation of the water-stable base layer and the spraying operation of the penetration oil are completed, or the road surface rolling operation starts after the paving operation of the water-stable base layer and the spraying operation of the penetration oil are constructed a preset distance.

[0020] The second aspect of the present invention further provides a spraying system for use in any one of the above-mentioned construction methods, the spraying system comprising:

[0021] A heat storage tank, wherein the heat storage tank is arranged on a vehicle frame having an independent power system;

[0022] A spraying rod, which is detachably mounted on the paver and has a channel and a plurality of nozzles connected to the channel, and a valve is also provided at the inlet end of the channel;

[0023] A communicating pipe has one end connected to the heat storage tank and the other end communicated with the inlet end of the channel, and a power pump is also provided on the communicating pipe.

[0024] In one specific embodiment of the present invention, the thermal storage tank comprises:

[0025] A tank body, with a containing cavity therein;

[0026] A heating unit, comprising a heating element disposed on the tank body and a power supply control system connected to the heating element;

[0027] The packaging part includes a heat preservation material and a heat insulating material which are wrapped around the outer side of the tank body and the heating element from the inside to the outside.

[0028] In a specific embodiment of the present invention, a fixed bracket is provided at the rear of the paver, and the spraying rod is detachably mounted on the fixed bracket.

[0029] In a specific embodiment of the present invention, a spring shock absorber is further provided on the fixed bracket, and the spraying rod is mounted on the spring shock absorber; and / or

[0030] The length of the fixing bracket is not less than 50 cm; and / or

[0031] On the spraying rod, the distance between two adjacent nozzles is 5-30 cm.

[0032] The construction method of a water-stable base pavement with an asphalt surface layer provided by the present invention implements a penetration oil spraying operation on the surface of the water-stable base formed by paving operations, and then implements an asphalt surface spraying operation on the rolled road surface, thereby solving the problems of difficult penetration of the penetration oil and insufficient penetration depth; at the same time, spraying the penetration oil and spraying the asphalt surface layer provides a stable humidity environment for water-stable curing, saving curing costs and making the curing simple and efficient; at the same time, the penetration oil can also improve the bonding performance of the asphalt surface layer, which is beneficial to extending the life of the road surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 A flowchart of a construction method in one embodiment of the present invention;

[0035] Figure 2 It is a schematic diagram of paving operation in an embodiment of the present invention. DETAILED DESCRIPTION

[0036] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0037] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0038] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0039] For ease of description, spatial relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figure, such as "inside", "outside", "inner side", "outer side", "below", "below", "above", "above", etc. Such spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figure. For example, if the device in the figure is turned over, then the elements described as "below other elements or features" or "below other elements or features" will subsequently be oriented as "above other elements or features" or "above other elements or features". Therefore, the example term "below..." can include both upper and lower orientations. The device can be oriented otherwise (rotated 90 degrees or in other directions) and the spatial relative descriptors used in the text are interpreted accordingly.

[0040] The first aspect of the present invention provides a construction method for a water-stable base pavement with an asphalt surface layer, which can solve or at least partially solve the problems of difficult penetration and insufficient penetration depth of the oil-stable layer in the construction of water-stable base pavements in the related art, thereby improving the bonding ability between the water-stable base and the asphalt surface layer and increasing the life of the pavement.

[0041] Reference Figure 1-2 Specifically, the construction method comprises the following steps:

[0042] Step 1: Pre-treat the base layer.

[0043] Specifically, the subbase is a cement-stabilized crushed stone base, which is a small amount of cement, coarse and fine aggregates, water and additives mixed and compacted, and its thickness is generally 18 to 20 cm. Pretreatment of the subbase includes cleaning the subbase to remove obvious large particles on the subbase so that the surface of the subbase is basically flat. Then, cement slurry or cement is spread on the surface of the subbase.

[0044] Step 2: Perform paving operations on the surface of the pre-treated lower base layer, and simultaneously perform penetrating oil spraying operations on the surface of the water-stable base layer formed by the paving operation.

[0045] Specifically, the paving operation is carried out by the paver 10, and the paver 10 is provided with a hopper, and the hopper is provided with a material cavity and a paving seam connected to the material cavity, wherein the mixed water-stable base material is carried in the material cavity, and as the paver 10 moves forward, the water-stable base material can slide down from the paving seam and be spread and formed behind the paver 10, thus forming a water-stable base.

[0046] In actual operation, the paver 10 paves at a uniform speed of 1.7 km / h to 2 km / h, so that the water-stable base material can be paved behind the paver 10 to form a water-stable base of a predetermined thickness. Exemplarily, the thickness of the water-stable base is 7 to 70 cm. For example, the thickness of the water-stable base is 7 cm, 10 cm, 15 cm, 20 cm, 25 cm, 30 cm, 35 cm, 40 cm, 50 cm, 60 cm, and 70 cm.

[0047] The penetration oil is sprayed in real time while the water-stable base is being paved. Specifically, the penetration oil is sprayed on the surface of the water-temperature base formed by the paving operation. The penetration oil is a quick-cracking emulsified asphalt, and the spreading amount is 1.5±0.1L / m 2 The thickness of the formed penetrating oil layer is 1-20mm.

[0048] Step 3: Carry out road rolling operation on the water-stable base layer sprayed with penetrating oil, and carry out asphalt surface spraying operation on the compacted road surface within 24 hours after the completion of the road rolling operation.

[0049] Specifically, the road surface rolling operation can be carried out immediately after the simultaneous spraying of emulsified asphalt on the water-stable base is completed, or the rolling operation can be started after a preset distance of the simultaneous spraying of emulsified asphalt on the water-stable base, wherein the preset distance can be specifically 500-10000m.

[0050] Road compaction operations include:

[0051] Use a double steel wheel roller to perform static compaction once, with a compaction speed of 1.5km / h to 2km / h;

[0052] Use a vibratory roller to roll once, with a rolling speed of 2 to 2.5 km / h;

[0053] Use a rubber-wheel roller to roll the road twice at a speed of 2 to 2.5 km / h until the water-stable base road surface is smooth and free of wheel marks.

[0054] After that, the asphalt surface is sprayed on the compacted road surface. The raw material of the asphalt surface is quick-cracking emulsified asphalt, and the spreading amount is 1±0.1L / m 2 .

[0055] Step 4: Perform curing treatment on the water-stable base pavement sprayed with the asphalt surface layer to obtain a water-stable base pavement with an asphalt surface layer.

[0056] Specifically, health care

[0057] The curing treatment time is at least 7 days. After the curing is completed, a water-stabilized base pavement with an asphalt surface layer can be obtained.

[0058] Compared with the traditional curing mode of using geotextile and continuous watering, the curing mode of simultaneous paving and spraying of emulsified asphalt in this method has the advantage of deep penetration, which blocks the water in the water-stable base and achieves the purpose of water saving.

[0059] It should be noted that before spraying quick-cracking emulsified asphalt, it is necessary to use geotextiles or plastic film to cover existing retaining walls, sidewalks, roadsides, drainage ditches and other road structures to prevent the emulsified asphalt from being accidentally sprayed on them.

[0060] In addition, the environmental conditions for paving operations of the water-stable base layer, spraying of penetration oil and spraying of the asphalt surface layer are non-rainy weather with a temperature of no less than 10°C. This can reduce the impact of environmental conditions on road construction and improve the quality and service life of the road.

[0061] The second aspect of the present invention also provides a spraying system for use in any of the above-mentioned construction methods, the spraying system comprising a heat storage tank, a spraying rod 20 and a connecting pipe, wherein the heat storage tank is arranged on a frame with an independent power system; the spraying rod 20 is detachably mounted on the paver 10, and is provided with a channel and a plurality of nozzles connected to the channel, and a valve is also provided at the inlet end of the channel; one end of the connecting pipe is connected to the heat storage tank, and the other end is connected to the inlet end of the channel, and a power pump is also provided on the connecting pipe.

[0062] Specifically, the hot storage tank is not only used to store the quick-cracking emulsified asphalt, but also used to heat and insulate the quick-cracking emulsified asphalt to keep it in a fluid state. The vehicle frame with an independent power system can be a paver 10, that is, the spraying system is directly arranged on the paver 10, or it can be a separately arranged vehicle. For example, the hot storage tank is arranged on a separately arranged vehicle, which can improve the mobility and convenience of the spraying system, thereby facilitating application.

[0063] The spraying rod 20 is a spraying structure, which is detachably mounted on the rear side of the paver 10 and is provided with a plurality of nozzles. The storage tank and the spraying rod 20 are used to transport the quick-cracking emulsified asphalt in the hot storage tank to the spraying rod 20.

[0064] Specifically, when the penetration oil spraying operation is carried out simultaneously on the surface of the water-stable base layer formed by the paving operation, the vehicle and the paver 10 are arranged side by side, and the driving speeds of the two are kept consistent. At the same time, the power pump is started. Driven by the power pump, the fast-cracking emulsified asphalt in the hot storage tank flows to the spray rod 20 and is sprayed through the nozzle on the spray rod 20 to the surface of the water-stable base layer formed by the paving operation, thereby realizing the penetration oil operation.

[0065] In one embodiment, a heat storage tank includes a tank body, a heating part and a packaging part, wherein a accommodating cavity is arranged in the tank body; the heating part includes a heating element arranged on the tank body and a power control system connected to the heating element; and the packaging part includes a heat preservation material and a thermal insulation material wrapped around the tank body and the outside of the heating element from the inside to the outside.

[0066] Specifically, the tank body is a sealed container with a containing cavity, and its cross-section can be formed into a circular or elliptical shape. The tank body also has a pipe mouth of a valve, which is used to inject quick-cracking emulsified asphalt into the containing cavity and can also be used to transport quick-cracking emulsified asphalt to the spray rod 20.

[0067] The heating unit is arranged on the tank body, and is used to heat the tank body so as to keep the tank body within a preset temperature range, thereby preventing the quick-cracking emulsified asphalt therein from solidifying.

[0068] The packaging part is used to insulate the tank body, thereby improving its thermal effect.

[0069] In one embodiment, a fixed bracket is provided at the rear of the paving machine 10, and the spraying rod 20 is detachably mounted on the fixed bracket. Specifically, the fixed bracket ensures that the spraying rod 20 extends 50 cm outside the mixing cage, and a spring shock absorber is also provided on the fixed bracket, and the spraying rod 20 is mounted on the spring shock absorber.

[0070] In one embodiment, the distance between two adjacent nozzles on the spraying rod 20 is 5-30 cm.

[0071] The spray rod 20 is a three-section folding structure, the height of which can be adjusted up and down, and the length of the spray rod 20 can be extended left and right to adjust. A valve is provided at the entrance of the spray rod 20, and nozzles are arranged equidistantly below the spray rod 20; the nozzle spacing is 5-30cm, preferably, the nozzle spacing is 10cm, and the spray strip in the nozzle is set to be deflected 30 degrees counterclockwise from the spray rod 20 to ensure uniform spraying and avoid interference with the emulsified asphalt spraying of adjacent nozzles.

[0072] Before spraying quick-cracking emulsified asphalt, it is necessary to determine the spraying width and asphalt pump flow rate. Specifically, the spraying width and asphalt pump flow rate need to be determined. Specifically, the spraying width and the ... 2 emulsified asphalt; asphalt pump flow, calculated by formula 1 Q = 1000q / vl, where Q is the asphalt pump flow, (m 3 / s); q is the spreading amount, L / m 2 ; v is the speed of the spreading vehicle, m / s; l is the spreading width, m. The amount of emulsified asphalt sprayed can then be ensured by adjusting the electric valve on the power pump.

[0073] In one embodiment, in order to further improve the synchronization between the paving operation and the penetration oil spraying operation, the spraying system can be electrically connected to the paver 10, and the quick-cracking emulsified asphalt can be sprayed immediately when the paving starts.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A construction method for a water-stable base pavement with an asphalt surface layer, characterized in that: include: Step 1: Pre-treat the base layer; Step 2: Perform paving operations on the surface of the pre-treated lower base layer, and simultaneously perform penetrating oil spraying operations on the surface of the water-stable base layer formed by the paving operation; Step 3: Perform pavement rolling on the water-stable base layer sprayed with penetration oil, and perform asphalt surface spraying on the compacted pavement within 24 hours after the pavement rolling operation is completed; Step 4: Perform curing treatment on the water-stable base pavement sprayed with the asphalt surface layer to obtain a water-stable base pavement with an asphalt surface layer.

2. The construction method according to claim 1, characterized in that: The pretreatment in step 1 includes cleaning the lower base and spreading cement slurry or cement on the lower base after cleaning.

3. The construction method according to claim 1, characterized in that: The penetration oil in step 2 and the asphalt surface sprayed in step 3 are both fast-cracking emulsified asphalt; and / or in step 2, the spraying amount of the emulsified asphalt is 1.5±0.1L / m 2 In step 3, the spraying amount of the emulsified asphalt is 1±0.1L / m 2 .

4. The construction method according to claim 1, characterized in that: The road compaction operation in step 3 includes: Use a double steel wheel roller to perform static compaction once, with a compaction speed of 1.5km / h to 2km / h; Use a vibratory roller to roll once, with a rolling speed of 2 to 2.5 km / h; Use a rubber-wheel roller to roll the road twice at a speed of 2 to 2.5 km / h.

5. The construction method according to claim 1, characterized in that: The environmental conditions for paving operations of water-stable base layers, spraying of penetration oil and spraying of asphalt surface layers are non-rainy weather with a temperature not less than 10°C.

6. The construction method according to claim 1, characterized in that: After the paving operation of the water-stable base layer and the spraying operation of the penetration oil are completed, the road surface rolling operation will be started immediately, or after the paving operation of the water-stable base layer and the spraying operation of the penetration oil are completed a preset distance, the road surface rolling operation will be started.

7. A spraying system, characterized in that: Used in the construction method according to any one of claims 1 to 6, the spraying system comprises: A heat storage tank, wherein the heat storage tank is arranged on a vehicle frame having an independent power system; A spraying rod, which is detachably mounted on the paver and has a channel and a plurality of nozzles connected to the channel, and a valve is also provided at the inlet end of the channel; A communicating pipe has one end connected to the heat storage tank and the other end communicated with the inlet end of the channel, and a power pump is also provided on the communicating pipe.

8. The spraying system according to claim 7, characterized in that The thermal storage tank comprises: A tank body, with a containing cavity therein; A heating unit, comprising a heating element disposed on the tank body and a power supply control system connected to the heating element; The packaging part includes a heat preservation material and a heat insulating material which are wrapped around the outer side of the tank body and the heating element from the inside to the outside.

9. The spraying system according to claim 7, characterized in that: A fixed bracket is arranged at the rear of the paver, and the spraying rod is detachably mounted on the fixed bracket.

10. The spraying system according to claim 9, characterized in that The fixing bracket is further provided with a spring shock absorber, and the spraying rod is mounted on the spring shock absorber; and / or The length of the fixing bracket is not less than 50 cm; and / or On the spraying rod, the distance between two adjacent nozzles is 5-30 cm.

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