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CN-122010487-A - Fiber concrete preparation for pavement, preparation method thereof and pavement construction method

CN122010487ACN 122010487 ACN122010487 ACN 122010487ACN-122010487-A

Abstract

A fiber concrete preparation for a pavement and a preparation method thereof and a pavement construction method relate to the technical field of pavement construction and solve the problem of poor performances such as elasticity, durability and the like of the existing pavement. Comprises cementing material composed of silicate cement, granulated blast furnace slag powder and silica fume, aggregate composed of continuous graded broken stone and machine-made sand, composite fiber composed of basalt fiber and polyvinyl alcohol fiber, functional additive composed of water reducing agent, water retaining agent and defoamer, catalyst composed of nano silicon dioxide and tricalcium aluminate and water. The pavement construction method comprises the steps of paving the preparation within 30min, vibrating by a high-frequency vibrator, leveling by a laser leveling machine, covering geotextile, and curing under standard conditions. The invention can be applied to pavement construction, and is particularly suitable for severe pavement scenes such as severe cold, heavy load and the like.

Inventors

  • GUAN GUOYING
  • WANG HONGYU
  • XIAO CHONGLI
  • SONG KUNZE
  • ZHANG CHANGLI

Assignees

  • 吉林建筑大学
  • 吉林省亚安新材料有限公司

Dates

Publication Date
20260512
Application Date
20260119

Claims (9)

  1. 1. The fiber concrete preparation for the pavement is characterized by comprising the following components in parts by weight: 300-450 parts of cementing material, 1200-1600 parts of aggregate, 15-30 parts of composite fiber, 8-15 parts of functional additive, 2-5 parts of catalyst and 120-180 parts of water; The cementing material consists of silicate cement, granulated blast furnace slag powder and silica fume in a mass ratio of 5:3:2, wherein the strength grade of the silicate cement is not lower than P.O42.5; The aggregate is a mixture of continuous graded broken stone and machine-made sand with the mass ratio of 7:3-8:2; the composite fiber is a compound body of basalt fiber and polyvinyl alcohol fiber with the mass ratio of 2:1-3:1; The catalyst is a compound body of nano silicon dioxide and tricalcium aluminate in a mass ratio of 1:1-1:2; the functional additive comprises a water reducer, a water-retaining agent and a defoaming agent in a mass ratio of 6:3:1.
  2. 2. The fiber concrete formulation for pavement according to claim 1, wherein the basalt fiber has a length of 12 to 18mm and a diameter of 13 to 18 μm.
  3. 3. The fiber concrete formulation for pavement according to claim 1, wherein the polyvinyl alcohol fiber has a length of 8 to 12mm and a diameter of 20 to 30 μm.
  4. 4. The fiber concrete preparation for pavement according to claim 1, wherein the particle size of nano silicon dioxide in the special catalyst is less than or equal to 50nm, and the purity of tricalcium aluminate is more than or equal to 95%.
  5. 5. The fiber concrete formulation for pavement according to claim 1, wherein the crushed stone has a particle size ranging from 5 to 20mm and a machine-made sand fineness modulus of 2.6 to 3.0.
  6. 6. The fiber concrete formulation for pavement according to claim 1, wherein the water reducing agent is polyethylene glycol monomethyl ether methacrylate-acrylic acid copolymer, the water retaining agent is hydroxypropyl methylcellulose, and the defoaming agent is polyoxypropylene polyoxyethylene ether or glycerol monostearate.
  7. 7. A method for preparing the fiber concrete formulation for pavement according to any one of claims 1 to 6, comprising the steps of: Putting the aggregate into a stirrer, carrying out dry mixing for 2-3 min, then adding the composite fiber, and continuing to carry out dry mixing for 1-2 min to uniformly disperse the fiber in the aggregate to obtain a premix; Mixing the cementing material and the functional additive, stirring for 1-2 min, then adding 70% of water, and stirring for 3-5 min to form uniform slurry; Adding a catalyst into the residual water, performing ultrasonic dispersion for 5-10 min to prepare a catalytic liquid, slowly adding the catalytic liquid into the slurry, stirring for 2-3 min, pouring into the premix, and stirring for 5-8 min until the mixture is uniform, and obtaining the fiber concrete composition without agglomeration and segregation phenomena.
  8. 8. A pavement construction method characterized by applying the fiber concrete formulation for pavement according to any one of claims 1 to 6, comprising the steps of: Paving the fiber concrete preparation for the pavement within 30min, wherein the paving thickness is 5-8mm higher than the designed pavement thickness, vibrating for 20-30 s/point by adopting a high-frequency vibrator, leveling by adopting a laser leveling machine after vibrating, covering geotextiles, and curing for 14-21 d under the conditions of 20-25 ℃ and relative humidity of more than or equal to 85%.
  9. 9. The pavement construction method according to claim 8, wherein the frequency of the high-frequency vibrator is set to 150 to 200hz and the amplitude is set to 2 to 3mm.

Description

Fiber concrete preparation for pavement, preparation method thereof and pavement construction method Technical Field The invention relates to the technical field of road construction, in particular to a fiber concrete preparation for a road surface, a preparation method thereof and a road surface construction method. Background The pavement concrete is used as a core structural material of road engineering, and the performance of the pavement concrete directly determines the bearing capacity, traffic safety and service life of the road. The material takes cementing materials (cement, mineral admixture and the like), aggregate and water as basic components, and forms a compact cementing framework through hydration reaction, so as to bear vehicle load and environmental erosion. The ideal pavement concrete needs to meet three core requirements simultaneously. The construction method has the advantages of good workability and stability in the construction stage, avoiding die collapse, excellent mechanical strength, elasticity and crack resistance in the use stage, resisting temperature shrinkage and dry shrinkage stress and load impact, and strong durability in long-term service, and resisting environmental damage such as freeze thawing cycle, carbonization, salt corrosion and the like. The fiber reinforcement technology is a mainstream scheme for improving the performance of concrete, and the core principle is that chopped fibers are uniformly dispersed in a concrete matrix, and the effects of bridging cracks and dispersing stress are realized through the interface bonding effect of the fibers and the matrix. When the concrete is loaded to generate micro-cracks, the fibers can transfer the stress at two ends of the cracks, inhibit the crack from expanding, and improve the toughness and the shock resistance of the concrete. Among a plurality of fiber types, basalt fibers are a common reinforcing material of pavement concrete due to high tensile strength, excellent corrosion resistance and outstanding cost performance, and polyvinyl alcohol (PVA) fibers are obvious in the aspect of inhibiting early shrinkage cracks by virtue of excellent elasticity, compatibility with a cement matrix and crack resistance effect, so that the two fibers are combined into a research direction for combining strength and elasticity. However, the existing pavement concrete technology based on the compounding of basalt fibers and PVA fibers still has a plurality of defects to be solved urgently. Firstly, the fiber synergistic enhancement effect is poor, most schemes simply mix two kinds of fibers, and the compounding proportion and parameters are not optimized according to the pavement stress characteristics, so that the high strength advantage of basalt fibers and the high elasticity advantage of PVA fibers can not be fully exerted, the elastic modulus and the elongation at break of concrete are difficult to reach standards at the same time, and rigid fracture easily occurs when the heavy-duty vehicle repeatedly impacts. Secondly, the balance contradiction between construction stability and performance is outstanding, the water consumption or the admixture dosage is often required to be increased to improve the fiber dispersibility, so that the concrete setting speed is reduced, the phenomenon of mould collapse and layering easily occurs due to dead weight or vibration in the construction process, and the risk of shrinkage cracks in the later stage is increased by simply increasing the cement dosage to accelerate setting. Thirdly, the existing pavement concrete catalyst mostly aims at accelerating coagulation or reducing hydration heat, the most common catalyst is aluminate catalyst, although the coagulation time can be shortened, the structure of an interface transition region between fibers and a matrix cannot be improved, the fiber reinforcement effect is limited, micro cracks are easily generated due to interface defects in the later stage of concrete, and the durability is reduced. Fourth, the service life is still a bottleneck, and is affected by the defects, the average service life of the existing fiber reinforced pavement concrete is usually only 8-12 years, the service life is shorter than 5-8 years due to the coupling effect of freeze thawing cycle and crack expansion in northern cold areas, the milling and re-paving are required to be frequently carried out, the maintenance cost is increased, and the traffic passing efficiency is affected. Therefore, development of a high-elasticity durable pavement concrete material with fiber synergistic enhancement, stable construction, coagulation control and interface structure optimization has become an urgent need for cracking industry pain points. Disclosure of Invention In order to solve the problem of poor performances such as elasticity and durability of the existing pavement, the invention provides a fiber concrete preparation for the pavement, a preparation method thereof and