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CN-121974620-A - Steel fiber reinforced ultra-high performance concrete slab and preparation method thereof

CN121974620ACN 121974620 ACN121974620 ACN 121974620ACN-121974620-A

Abstract

The invention discloses a steel fiber reinforced ultra-high performance concrete slab and a preparation method thereof, and relates to the field of assembly type buildings. Aiming at the problems that the interface compatibility of rubber powder and a cement matrix in the existing concrete slab is poor, the dispersion of steel fibers is uneven, the curing process is extensive, and the high strength and the sound insulation and noise reduction performance are difficult to achieve, the invention adopts sodium hydroxide pretreatment combined with an interface hybridization modifier to modify the rubber powder, prepares a special fiber plasticizer containing calcium nitrate to optimize the dispersion of the steel fibers, adopts a staged refined temperature and humidity curing process to carry out standard curing, and designs a multi-form hollow duct structure to optimize the performance of the concrete slab. The concrete slab prepared by the method has the advantages of light dead weight, high mechanical strength, remarkable improvement of crack resistance and water resistance, good sound insulation and noise reduction effects, and suitability for high-frequency and high-load application scenes such as rail transit, urban overhead and the like.

Inventors

  • YAO XIN
  • Yang Liuyiyi
  • XIE MINGJIE
  • Liang Deyue
  • YANG XIAOHUA

Assignees

  • 华惠宏瑾新材料科技(上海)有限公司
  • 湖南工业大学

Dates

Publication Date
20260505
Application Date
20251226

Claims (9)

  1. 1. The preparation method of the steel fiber reinforced ultra-high performance concrete slab comprises the following preparation steps: s1, carrying out dry mixing on cement, silica fume, fly ash, quartz sand, surface modified rubber powder, light ceramsite, steel fiber, fiber plasticizer and polycarboxylic acid high-performance water reducer, uniformly stirring, and then adding water to stir to obtain the surface modified rubber powder fiber reinforced ultra-high-performance concrete; s2, transferring the surface modified rubber powder steel fiber reinforced ultra-high performance concrete into a plate mold with a pore canal, and preparing an ultra-high performance concrete plate by cast-in-situ or extrusion molding; and S3, carrying out standard maintenance on the ultra-high performance concrete slab to obtain the steel fiber reinforced ultra-high performance concrete parallel pore hollow slab.
  2. 2. The preparation method of the steel fiber reinforced ultra-high performance concrete hollow slab according to claim 1 is characterized in that in step S1, the steel fiber reinforced ultra-high performance concrete hollow slab comprises, by weight, 800-900 parts of cement, 100-200 parts of fly ash, 100-300 parts of silica fume, 500-900 parts of quartz sand, 150-200 parts of lightweight ceramsite, 150-200 parts of surface modified rubber powder, 30-60 parts of steel fiber, 55-90 parts of polycarboxylic acid high performance water reducer, 50-80 parts of fiber plasticizer and 380-450 parts of water.
  3. 3. The method for preparing the steel fiber reinforced ultra-high performance concrete hollow slab according to claim 1, wherein the method for preparing the surface modified rubber powder comprises the following steps: A1, adding rubber powder into a sodium hydroxide solution, heating and soaking, cooling, washing with clear water to be neutral, and airing to obtain pretreated rubber powder; A2, adding dibenzoyl peroxide into absolute ethyl alcohol, uniformly stirring, adding sodium silicate and deionized water, heating and uniformly stirring to obtain an interface hybridization modifier; a3, adding the pretreated rubber powder into an interface hybridization modifier, stirring at a constant temperature of 70-90 ℃ for reaction for 1-2 h, cooling, filtering, and carrying out heat treatment and solidification at 100-120 ℃ for 1-2 h to obtain the surface modified rubber powder.
  4. 4. The preparation method of the steel fiber reinforced ultra-high performance concrete hollow slab according to claim 3, wherein the surface modified rubber powder comprises, by weight, 100 parts of rubber powder, 300-400 parts of sodium hydroxide solution, 1.5-2.5 parts of dibenzoyl peroxide, 35-45 parts of absolute ethyl alcohol, 8-12 parts of sodium silicate and 50-60 parts of deionized water.
  5. 5. The method for preparing the steel fiber reinforced ultra-high performance concrete slab according to claim 1, wherein the method for preparing the fiber plasticizer comprises the following steps: b1, adding deionized water into a reaction kettle, sequentially adding hydroxypropyl methylcellulose, ethylene oxide and sodium gluconate, and heating to 70-80 ℃ and dispersing for 15-25 min at 4000-6000 rpm to obtain a solution B1; B2, adding silica sol into the solution B1, and uniformly stirring at 70-80 ℃ to form a composite colloid; And B3, cooling the composite colloid to 40-45 ℃, adding calcium nitrate, and uniformly stirring to obtain the fiber plasticizer.
  6. 6. The preparation method of the steel fiber reinforced ultra-high performance concrete slab according to claim 5, wherein the fiber plasticizer comprises, by weight, 12-18 parts of hydroxypropyl methylcellulose, 6-9 parts of ethylene oxide, 4-6 parts of sodium gluconate, 25-35 parts of silica sol, 0.8-1.2 parts of calcium nitrate and 70-90 parts of deionized water.
  7. 7. The method for preparing the steel fiber reinforced ultra-high performance concrete hollow slab according to claim 1, wherein in the step S3, the standard curing method is characterized in that the ultra-high performance concrete hollow slab is placed in a curing chamber, the temperature is controlled to be 18-30 ℃ and the humidity is controlled to be 85-99% in the initial setting period of 0-1 day, the temperature is controlled to be 15-30 ℃ and the humidity is controlled to be 70-99% in the hardening period of 1-7 days, and the temperature is controlled to be 15-30 ℃ and the humidity is controlled to be 70-99% in the continuous curing period of 7-28 days.
  8. 8. The preparation method of the steel fiber reinforced ultra-high performance concrete hollow slab according to claim 1, wherein the steel fiber reinforced ultra-high performance concrete hollow slab has the width of 300mm-900mm, the length of 3.0m-6.0m and the thickness of 60mm-150mm, the steel fiber reinforced ultra-high performance concrete slab is made into a hollow structure, namely hollow channels are arranged in parallel along the length direction of the slab, the channel shape is selected from any one of rectangle, circle, ellipse, regular octagon, combination of regular octagon and triangle, and regular hexagon honeycomb, the separation wall thickness between the channels is 7.0mm-12.0mm, and the thickness of the outer edge of the channel is 7.0mm-15.0mm from the slab surface.
  9. 9. A steel fiber reinforced ultra-high performance concrete hollow slab prepared by the method for preparing a steel fiber reinforced ultra-high performance concrete hollow slab according to any one of claims 1 to 8.

Description

Steel fiber reinforced ultra-high performance concrete slab and preparation method thereof Technical Field The invention relates to the field of assembled buildings, in particular to a steel fiber reinforced ultra-high performance concrete hollow slab and a preparation method thereof. Background In the field of assembly type buildings, the ultra-high performance concrete hollow slab is an important material for scenes such as sound barrier plates, outdoor decorative plates, inner and outer wall partition plates and the like by virtue of excellent mechanical properties and durability, wherein the sound barrier plates simultaneously meet multiple requirements of impact resistance, sound insulation, noise reduction, weather resistance and the like. The conventional concrete slabs on the market are mostly based on common cement-based materials and are simply reinforced by matching with a small amount of fibers, and can meet the use conditions of the foundation, but under the application scenes of high frequency and high load such as rail transit, urban overhead, and the like, the conventional concrete slabs are difficult to combine high strength, high toughness and good sound insulation and noise reduction effects, and have insufficient suitability. When the existing ultra-high performance concrete slab is prepared, certain lightweight aggregates are added to improve the sound insulation and noise reduction performance, and the compatibility of the lightweight aggregates with the cement matrix is poor, so that the problems of high interfacial porosity, insufficient bonding strength and the like are easily caused. The conventional fiber plasticizer has limited effect, cannot effectively improve the dispersion state of steel fibers in a concrete matrix, and is easy to cause aggregation phenomenon, thereby directly affecting the homogeneity and mechanical property stability of the concrete slab. The existing curing process of concrete slabs lacks of fine management and control, most schemes do not adjust temperature and humidity parameters according to the characteristics of different stages of initial setting, hardening, continuous curing and the like of concrete, so that insufficient hydration reaction in the concrete is easily caused, and further uneven plate strength development and increased shrinkage cracking risk are caused. In addition, the duct design form of partial sound barrier board is single, does not combine the optimization duct shape of sound insulation demand and size parameter, has further restricted the promotion of concrete slab sound insulation and noise reduction performance, is difficult to fit the development demand of current building field to high performance, multi-functional concrete slab. Disclosure of Invention In view of the above, the invention aims to provide the steel fiber reinforced ultra-high performance concrete hollow slab and the preparation method thereof, which effectively solve the problems of poor interfacial compatibility between lightweight aggregate and a cement matrix, uneven dispersion of steel fibers and unstable mechanical properties in the traditional ultra-high performance concrete slab, and simultaneously solve the defects of insufficient concrete hydration and high shrinkage cracking risk caused by the fact that the temperature and humidity are not regulated and controlled in stages in the traditional curing process, and further overcome the defects of single duct design, difficulty in considering high strength, high toughness and insufficient sound insulation and noise reduction performances in the traditional concrete slab. The aim of the invention can be achieved by the following technical scheme: The invention provides a preparation method of a steel fiber reinforced ultra-high performance concrete hollow slab, which comprises the following preparation steps: S1, adding cement, silica fume, fly ash, quartz sand, surface modified rubber powder, light ceramsite, steel fiber, fiber plasticizer and polycarboxylic acid high-performance water reducer into a stirring device for dry stirring, and adding water for stirring after uniform stirring to obtain surface modified rubber powder fiber reinforced ultra-high-performance concrete; S2, transferring the surface modified rubber powder fiber reinforced ultra-high performance concrete into a concrete hollow slab mold, and preparing the ultra-high performance concrete hollow slab by cast-in-situ or extrusion molding; And S3, carrying out standard maintenance on the ultra-high performance concrete hollow slab to obtain the steel fiber reinforced ultra-high performance concrete slab. Further, the step S1 comprises the following raw materials, by weight, 800-900 parts of cement, 100-200 parts of fly ash, 100-300 parts of silica fume, 500-900 parts of quartz sand, 150-200 parts of light ceramsite, 150-200 parts of surface modified rubber powder, 30-60 parts of steel fiber, 55-90 parts of polycarboxylic acid high-perform