Construction method for dry and hard concrete of airport pavement

Abstract

The invention discloses an airport pavement hard concrete construction method in the technical field of concrete construction. The airport pavement hard concrete construction method comprises the following steps: preparing hard concrete containing an air entraining and water reducing agent and an anti-freezing agent; after surveying and lofting are conducted on the construction site environment, a formwork is manufactured and installed; after the dry and hard concrete is stirred, the dry and hard concrete is paved in the formwork; the paved dry hard concrete is vibrated, compacted, subjected to slurry extraction and finely leveled; trowelling and galling are conducted on the finely-leveled dry hard concrete; and curing the napped dry hard concrete. By optimizing the proportion of the concrete and adding the specific additive, the crack resistance and freezing resistance of the concrete are remarkably improved, and the common problems of cracking and freezing injury of the airfield pavement are effectively solved; and due to application of mechanical construction, the construction efficiency is greatly improved, the labor intensity of workers is reduced, and the working environment is improved.

Description

Technical Field

[0001] The invention relates to a dry hard concrete construction method for an airport pavement, belonging to the technical field of concrete construction. Background Art

[0002] With the rapid development of economic construction, various industries have developed rapidly. In recent years, the aerospace industry has developed rapidly. The safe takeoff and smooth landing of aircraft are inseparable from the quality of airport pavement.

[0003] During construction, cement concrete will gradually shrink and harden over time, and concrete does not have ductility. Therefore, during the construction process or use, when it is squeezed and stretched to a large extent to produce segregation, cement concrete will easily develop irregular cracks. In addition, concrete is a non-homogeneous, anisotropic, brittle material in structure, and the external temperature cannot be effectively controlled during construction. If the construction is carried out in a season with a large temperature difference, cracks may occur due to thermal expansion and contraction. Because cement concrete pavement construction has strict quality standards and requires repeated confirmation, which leads to an extension of the construction period, the concrete pavement soil may lose water due to special weather conditions, which in turn causes plastic shrinkage problems caused by drying, resulting in cracks on the pavement.

[0004] At present, the construction of dry and hard cement concrete pavement is mainly based on traditional manual labor. The disadvantages include low efficiency, high work intensity of workers, poor working environment, frequent quality problems, and increasingly high requirements for environmental protection and green construction, which necessitate the urgent need to improve the construction method.

[0005] A method for constructing dry-hard concrete for an airport pavement with publication number CN117626736A discloses the following steps: preparing dry-hard concrete; measuring and setting out, measuring the construction site environment, and making formwork; installing the formwork; mixing the dry-hard concrete, and transporting the mixed dry-hard concrete to the construction site; spreading the dry-hard concrete in the formwork at the construction site; vibrating the spread dry-hard concrete; leveling, compacting, and slurrying the vibrated dry-hard concrete; roughening the surface of the dry-hard concrete; covering and curing the roughened dry-hard concrete until the curing period expires, removing the formwork, and completing the airport pavement construction.

[0006] In a dry environment with large temperature differences, concrete is prone to irregular cracks, which affect the flatness, crack control, skid resistance and durability of the pavement. The existing construction methods do not adequately consider the frost resistance of concrete, which can easily cause pavement damage in cold areas. Summary of the invention

[0007] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for construction of dry hard concrete for airport pavement, which effectively enhances the crack resistance and frost resistance of concrete by optimizing the concrete mix ratio and combining mechanized construction means, improves construction efficiency, reduces the labor intensity of workers, and improves the working environment.

[0008] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0009] In a first aspect, the present invention provides a method for constructing dry hard concrete on an airport pavement, comprising:

[0010] Equipped with dry hard concrete containing air-entraining water-reducing admixture and antifreeze admixture;

[0011] After measuring and setting out the construction site environment, make and install the formwork;

[0012] After mixing the dry hard concrete, spread the dry hard concrete in the formwork;

[0013] Vibrate, compact, add slurry and level the dry hard concrete after paving;

[0014] Smooth and roughen the dry hard concrete after fine leveling;

[0015] Curing of dry hard concrete after roughening.

[0016] Furthermore, the dry hard concrete includes: steel slag, rock, medium-coarse sand, silicate cement, air-entraining water-reducing agent, water, anti-cracking fiber and antifreeze, and its components are calculated by weight: 300-400 parts of steel slag, 100-120 parts of rock, 100-120 parts of medium-coarse sand, 200-250 parts of silicate cement, 2-8 parts of air-entraining water-reducing agent, 70-90 parts of water, 2-8 parts of anti-cracking fiber, and 2-8 parts of antifreeze.

[0017] Furthermore, the vertical diameter of the rock is not less than 10 cm. The rock needs to be crushed when used, and the average size of the crushed rock is 3-5 mm.

[0018] Furthermore, the average size of the steel slag is 2-4 mm, and the mud content of the medium-coarse sand is ≤1%.

[0019] Furthermore, the air content of the air-entraining water-reducing agent is 3-5%, the anti-cracking fiber is polypropylene fiber, and the antifreeze agent is composed of polyacrylamide, sodium alkylbenzene sulfonate, ethylene glycol and sodium carboxymethyl cellulose.

[0020] Furthermore, the construction site environment is measured and laid out, including: before measuring and laying out, re-measure the measurement control points and the encrypted control points that need to be used. After confirmation, use a total station on the base layer that has passed the acceptance, and use the polar coordinate method to determine the position of the intersection of each block according to the size of the road surface block, and use an ink fountain to draw lines on the spot as the basis for the plane position of the template. The elevation of the template is controlled throughout the process using a level according to the third-class leveling.

[0021] Furthermore, the vibration frequency of the vibrating rod used to vibrate the dry hard concrete after paving is 7000-10000r / min.

[0022] Furthermore, the roughening brush used for roughening the dry hard concrete after fine leveling is made of a plastic rod with a diameter of 2.5 or 3 mm.

[0023] Furthermore, the roughened dry hard concrete is cured, including: covering the geotextile when the concrete surface begins to solidify, sprinkling water when the concrete surface under the geotextile turns gray, and keeping the geotextile in a moist state, and the curing period is not less than 14 days.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The present invention significantly improves the crack resistance and frost resistance of concrete by optimizing the concrete mix ratio and adding specific additives, effectively solving the common cracking and frost damage problems of airport pavements. The application of mechanized construction greatly improves the construction efficiency, reduces the labor intensity of workers, improves the working environment, and the strict quality control and monitoring system ensures the stability and reliability of the construction quality, thereby improving the overall performance and service life of the airport pavement.

[0026] 2. The antifreeze agent in the present invention is composed of polyacrylamide, sodium alkylbenzene sulfonate, ethylene glycol, and sodium carboxymethyl cellulose. Steel slag enhances the strength and durability of concrete, rock provides good aggregate support, medium-coarse sand optimizes the workability and compactness of concrete, silicate cement reduces the risk of temperature cracks, air-entraining water-reducing agent improves the frost resistance and durability of concrete, and the addition of polypropylene fiber and antifreeze agent further enhances the crack resistance and frost resistance of concrete. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0028] Figure 1 A construction method flow chart of a method for constructing dry hard concrete on an airport pavement provided in Embodiment 1 of the present invention. DETAILED DESCRIPTION

[0029] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0030] The following detailed description is an exemplary description, which is intended to provide further detailed description of the present invention. Unless otherwise specified, all technical terms used in the present invention have the same meaning as those generally understood by those skilled in the art to which the present invention belongs. The terms used in the present invention are only for describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present invention.

[0031] Embodiment 1:

[0032] See also Figure 1 , which is the first embodiment of the present invention, provides a method for constructing dry hard concrete on an airport pavement, comprising the following steps:

[0033] Prepare dry hard concrete, including: steel slag, rock, medium coarse sand, silicate cement, air entraining water reducer, water, anti-cracking fiber, antifreeze agent, and its components are calculated by weight as follows: 300 parts of steel slag, 100 parts of rock, 100 parts of medium coarse sand, 200 parts of silicate cement, 2 parts of air entraining water reducer, 70 parts of water, 2 parts of anti-cracking fiber, and 2 parts of antifreeze agent; the vertical diameter of the rock is not less than 10cm, and the rock needs to be crushed when used, and the average size of the crushed rock is 3mm; the average size of the steel slag is 2mm, and the mud content of the medium coarse sand is ≤1%; the air entraining water reducer The air content of the water agent is 3%, the anti-cracking fiber is polypropylene fiber, and the antifreeze agent is composed of polyacrylamide, sodium alkylbenzene sulfonate, ethylene glycol, and sodium carboxymethyl cellulose; steel slag enhances the strength and durability of concrete, mountain rocks provide good aggregate support, medium-coarse sand optimizes the workability and compactness of concrete, silicate cement reduces the risk of temperature difference cracks, air-entraining water-reducing agent improves the antifreeze and durability of concrete, and the addition of polypropylene fiber and antifreeze agent further enhances the anti-cracking performance and antifreeze ability of concrete; the influence of the proportion of preparation materials on antifreeze properties, the corresponding contents are as follows:

[0034] Steel slag and mountain rocks: Steel slag and mountain rocks are the main aggregates of concrete. The change in their proportion will directly affect the strength and durability of concrete. In this scheme, with the increase in the amount of steel slag and mountain rocks, the strength and durability of concrete have been significantly improved, thereby indirectly enhancing the frost resistance of concrete.

[0035] Medium-coarse sand: The optimal selection of medium-coarse sand can improve the workability and compactness of concrete, making it more uniform and dense, thereby reducing the penetration of moisture and air and improving the frost resistance of concrete;

[0036] Portland cement: The addition of Portland cement can reduce the risk of temperature cracks in concrete and improve the overall performance of concrete, thus having a positive impact on frost resistance;

[0037] Air-entraining water-reducing agent: Air-entraining water-reducing agent is one of the key factors to improve the frost resistance of concrete. By introducing an appropriate amount of tiny bubbles, the freezable water content in concrete can be reduced, the bubble structure can be improved, and the frost resistance of concrete can be improved. In this application, with the increase in the amount of air-entraining water-reducing agent, the frost resistance of concrete has been significantly improved.

[0038] Anti-crack fiber and antifreeze: The addition of anti-crack fiber and antifreeze can further improve the crack resistance and antifreeze ability of concrete; anti-crack fiber can enhance the toughness of concrete and reduce the occurrence of cracks; while antifreeze can lower the freezing point of concrete and reduce the damage to concrete caused by freezing.

[0039] Measure and lay out, accurately make and install templates to ensure construction accuracy; before measuring and laying out, re-measure the measurement control points and the encrypted control points to be used. After confirmation, use the total station on the base after acceptance, and use the polar coordinate method to determine the position of the intersection of each block according to the size of the road surface block, and use the ink fountain to draw lines on the spot as the basis for the plane position of the template. The elevation of the template is controlled throughout the process using a level meter according to the third-class leveling;

[0040] Use a mixer to mix the dry hard concrete, and spread the mixed dry hard concrete in the formwork;

[0041] The paver is equipped with a high-frequency vibrator for vibration, and the steel beam is vibrated to achieve compaction, slurry enhancement, and fine leveling, reduce bubbles and voids, and improve the density of concrete; the vibration frequency of the high-frequency vibrator is 7000r / min; there are still tiny bubbles on the surface of the concrete compacted by the paver vibrator, the cement slurry film is uneven, and the surface flatness is not up to standard. Therefore, the concrete needs to be further compacted, slurry enhanced, and finely leveled. The steel beam is arranged along the cross section of the concrete, vibrating up and down, with low amplitude and high frequency, to further compact, enhance slurry, and finely level the shallow surface;

[0042] Use an automatic trowel and a roughening brush to improve the surface flatness and roughness and enhance the skid resistance of the pavement. The roughening brush is made of a 2.5mm diameter plastic rod, divided into two layers, 120mm long, and 2mm apart. The average texture depth of the apron pavement is 0.4mm, so a 2.5mm diameter brush is sufficient. Straightening texture control: place an aluminum alloy ruler perpendicular to the longitudinal seam, and pull the brush against the ruler at a uniform speed with consistent force to make the texture of the entire board uniform, straight, and consistent in depth, to prevent the roughened texture from obliquely intersecting the transverse seam. To avoid wrinkles, the brush must not be stopped or vibrated during the roughening process. After each roughening, the cement slurry adhered to the brush should be cleaned immediately. Grasp the timing of roughening: if the roughening is done too early, it is easy to expose stones and sand, affecting the surface appearance; if the roughening is done too late, the required texture depth cannot be achieved. The determination of the roughening time is related to factors such as temperature, wind force, and slump of concrete. According to construction experience, it is best to press the concrete surface with your fingers until marks appear but the slurry does not stick. At this time, roughening can ensure the surface texture is uniform, the texture depth is deep, and the appearance is beautiful.

[0043] Implement concrete curing to ensure that the concrete is not adversely affected by the external environment during the hardening process;

[0044] During the construction process, radar detection and infrared temperature measurement are used to monitor the internal state of concrete and external environmental changes in real time, and construction parameters are adjusted in a timely manner to ensure that concrete performance meets standards.

[0045] In this embodiment, preferably, the corresponding contents of concrete curing are as follows:

[0046] When the concrete surface begins to solidify, cover it with geotextile. When the concrete surface under the geotextile turns gray, sprinkle water for maintenance and keep the geotextile moist. The maintenance period should be no less than 14 days. During the maintenance period, prevent the concrete surface from showing white and prohibit all vehicles from going on the road surface.

[0047] Embodiment 2:

[0048] See also Figure 1 , which is the second embodiment of the present invention, is based on the first embodiment, except that:

[0049] Prepare dry hard concrete, including: steel slag, rock, medium-coarse sand, silicate cement, air-entraining water-reducing agent, water, anti-cracking fiber, antifreeze agent, and its components are calculated by weight as follows: 350 parts of steel slag, 110 parts of rock, 110 parts of medium-coarse sand, 225 parts of silicate cement, 5 parts of air-entraining water-reducing agent, 80 parts of water, 5 parts of anti-cracking fiber, and 5 parts of antifreeze; the vertical diameter of the rock is not less than 10cm, and the rock needs to be crushed when used. The average size of the crushed rock is 4mm; the average size of the steel slag is 3mm, and the medium-coarse sand is 100 parts. The mud content is ≤1%; the air content of the air-entraining water-reducing agent is 4%, the anti-cracking fiber is polypropylene fiber, and the antifreeze agent is composed of polyacrylamide, sodium alkylbenzene sulfonate, ethylene glycol, and sodium carboxymethyl cellulose; steel slag enhances the strength and durability of concrete, mountain rocks provide good aggregate support, medium-coarse sand optimizes the workability and compactness of concrete, silicate cement reduces the risk of temperature difference cracks, air-entraining water-reducing agent improves the frost resistance and durability of concrete, and the addition of polypropylene fiber and antifreeze agent further enhances the crack resistance and frost resistance of concrete;

[0050] The paver is equipped with a high-frequency vibrator for vibration, and the vibrating steel beam is combined to achieve compaction, slurry lifting, and fine leveling, reduce bubbles and voids, and improve the density of concrete; the vibration frequency of the high-frequency vibrator is 8500r / min;

[0051] Use automatic trowel and roughening brush to improve surface flatness and roughness and enhance the skid resistance of the pavement. The roughening brush is made of 3mm diameter plastic rod, divided into two layers, 120mm long, 3mm spacing, the average texture depth of the taxiway pavement is 0.6mm, and a 3mm diameter brush is used.

[0052] Embodiment three:

[0053] See also Figure 1 , which is the third embodiment of the present invention, is based on the first embodiment, except that:

[0054] Prepare dry hard concrete, including: steel slag, rock, medium-coarse sand, silicate cement, air-entraining water-reducing agent, water, anti-cracking fiber, antifreeze agent, and its components are calculated by weight as follows: 400 parts of steel slag, 120 parts of rock, 120 parts of medium-coarse sand, 250 parts of silicate cement, 8 parts of air-entraining water-reducing agent, 90 parts of water, 8 parts of anti-cracking fiber, and 8 parts of antifreeze agent; the vertical diameter of the rock is not less than 10cm, and the rock needs to be crushed when used. The average size of the crushed rock is 5mm; the average size of the steel slag is 4mm, and the medium-coarse sand is 100mm. The mud content is ≤1%; the air content of the air-entraining water-reducing agent is 5%, the anti-cracking fiber is polypropylene fiber, and the antifreeze agent is composed of polyacrylamide, sodium alkylbenzene sulfonate, ethylene glycol, and sodium carboxymethyl cellulose; steel slag enhances the strength and durability of concrete, mountain rocks provide good aggregate support, medium-coarse sand optimizes the workability and compactness of concrete, silicate cement reduces the risk of temperature cracks, air-entraining water-reducing agent improves the frost resistance and durability of concrete, and the addition of polypropylene fiber and antifreeze agent further enhances the crack resistance and frost resistance of concrete;

[0055] Use a paver equipped with a high-frequency vibrator for vibration, and combine it with a vibrating steel beam to achieve compaction, slurry lifting, and fine leveling, reduce bubbles and voids, and improve concrete density; the vibration frequency of the high-frequency vibrator is 10,000 r / min;

[0056] Use an automatic trowel and a roughening brush to improve the surface flatness and roughness and enhance the pavement's anti-skid properties. The roughening brush is made of a 2.5mm diameter plastic rod, divided into two layers, 120mm long, with a spacing of 2mm. Generally, the average texture depth of the apron pavement surface is 0.4mm, so a 2.5mm diameter brush is sufficient.

[0057] The frost resistance test of the dry hard concrete in this embodiment is as follows:

[0058] The dry hard concrete of the present application was made into multiple square bodies, which were subjected to a low temperature environment of -20°C for 24 hours, a low temperature environment of -30°C for 24 hours, and a freeze-thaw cycle test. The measured results were: no cracks, no spalling; no cracks, no spalling; strength loss <5%, indicating that the concrete construction method of the present invention performed well, with no cracks, no spalling, and a strength loss of less than 5%, and had good anti-freeze performance.

[0059] It is known from common technical knowledge that the present invention can be implemented by other embodiments that do not deviate from its spirit or essential features. Therefore, the above disclosed embodiments are only illustrative in all respects and are not exclusive. All changes within the scope of the present invention or within the scope equivalent to the present invention are included in the present invention.

[0060] 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 above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for constructing dry hard concrete on an airport pavement, characterized in that: include: Equipped with dry hard concrete containing air-entraining water-reducing admixture and antifreeze admixture; After measuring and setting out the construction site environment, make and install the formwork; After mixing the dry hard concrete, spread the dry hard concrete in the formwork; Vibrate, compact, add slurry and level the dry hard concrete after paving; Smooth and roughen the dry hard concrete after fine leveling; Curing of dry hard concrete after roughening.

2. The airport pavement dry hard concrete construction method according to claim 1 is characterized in that: The dry hard concrete comprises: steel slag, rock, medium-coarse sand, silicate cement, air-entraining water-reducing agent, water, anti-cracking fiber and antifreeze agent, and its components are calculated by weight as follows: 300-400 parts of steel slag, 100-120 parts of rock, 100-120 parts of medium-coarse sand, 200-250 parts of silicate cement, 2-8 parts of air-entraining water-reducing agent, 70-90 parts of water, 2-8 parts of anti-cracking fiber and 2-8 parts of antifreeze agent.

3. The airport pavement dry hard concrete construction method according to claim 2 is characterized in that: The vertical diameter of the rock is not less than 10 cm. The rock needs to be crushed when used, and the average size of the crushed rock is 3-5 mm.

4. The airport pavement dry hard concrete construction method according to claim 2 is characterized in that: The average size of the steel slag is 2-4 mm, and the mud content of the medium-coarse sand is ≤1%.

5. The airport pavement dry hard concrete construction method according to claim 2 is characterized in that: The air content of the air-entraining water-reducing agent is 3-5%, the anti-cracking fiber is polypropylene fiber, and the antifreeze agent is composed of polyacrylamide, sodium alkylbenzene sulfonate, ethylene glycol and sodium carboxymethyl cellulose.

6. The airport pavement dry hard concrete construction method according to claim 1 is characterized in that: The construction site environment is measured and laid out, including: before measuring and laying out, the measurement control points and the encrypted control points to be used are re-measured. After confirmation, on the base layer that has passed the acceptance, a total station is used to use the polar coordinate method to determine the position of the intersection of each block according to the block size of the road surface, and an ink fountain is used to draw lines on the spot as the basis for the plane position of the template. The elevation of the template is controlled throughout the process using a level according to the third-class leveling.

7. The airport pavement dry hard concrete construction method according to claim 1 is characterized in that: The vibration frequency of the vibrating rod used to vibrate the dry hard concrete after paving is 7000-10000r / min.

8. The airport pavement dry hard concrete construction method according to claim 1 is characterized in that: The roughening brush used for roughening the dry hard concrete after fine leveling is made of a plastic rod with a diameter of 2.5 or 3 mm.

9. The airport pavement dry hard concrete construction method according to claim 1 is characterized in that: The roughened dry hard concrete is cured, including: covering the geotextile when the concrete surface begins to solidify, sprinkling water when the concrete surface under the geotextile turns gray, and keeping the geotextile moist. The curing period is not less than 14 days.

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