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CN-121554225-B - High-toughness high-strength concrete and well lid and preparation method thereof

CN121554225BCN 121554225 BCN121554225 BCN 121554225BCN-121554225-B

Abstract

The application discloses high-toughness high-strength concrete and a well lid and a preparation method thereof, belonging to the technical field of concrete well lids, wherein the well lid comprises, by weight, 100-120 parts of epoxy resin, 5-10 parts of absolute ethyl alcohol, 25-40 parts of T31 curing agent, 25-40 parts of modified carbon fiber-diatomite composite filler, 40-60 parts of fly ash, 5-10 parts of liquid nitrile rubber, 400-450 parts of quartz fine sand and 5-15 parts of modified basalt fiber. The concrete contains modified carbon fiber-diatomite composite filler and modified basalt fiber, under the action of impact load, the two components act together, so that the material has high compressive strength in the initial stress, can effectively dissipate energy when reaching a limit, resists sudden brittle fracture, forms stronger energy absorption and impact resistance, and can ensure effective inhibition and absorption of impact energy when facing to stress fracture of various types and different development stages under the synergistic effect, thereby obviously improving the integral anti-cracking impact resistance of the concrete.

Inventors

  • XU YI
  • HUANG RUI
  • HU DONGCAI
  • WU JIAO
  • SHI GUI
  • LI HAOHAO
  • KANG LING
  • MOU TINGMIN

Assignees

  • 四川省公路规划勘察设计研究院有限公司
  • 四川省公路院宏途新材科技有限公司

Dates

Publication Date
20260512
Application Date
20260123

Claims (10)

  1. 1. The high-toughness high-strength concrete is characterized by comprising, by weight, 100-120 parts of epoxy resin, 5-10 parts of absolute ethyl alcohol, 25-40 parts of a T31 curing agent, 25-40 parts of modified carbon fiber-diatomite composite filler, 40-60 parts of fly ash, 5-10 parts of liquid nitrile rubber, 400-450 parts of quartz fine sand and 5-15 parts of modified basalt fiber; The modified carbon fiber-diatomite composite filler is prepared by adding ethanol and deionized water into a reaction container, uniformly mixing, adding KH-550, continuously stirring, weighing carbon fibers, putting into the reaction container, ensuring that all the carbon fibers can be completely immersed in the solution, sealing a container mouth, standing and soaking for 8 hours, pouring out excessive solution after soaking for 8 hours, uniformly spreading out the extracted carbon fibers, airing in a well-ventilated area for 1-2 hours, preparing KH-550 modified carbon fibers, putting the KH-550 modified carbon fibers into a mortar, adding diatomite into the mortar, gently and fully mixing and stirring by using a pestle, spreading out the mixture in the container after uniformly stirring, and naturally drying for 12 hours to obtain the modified carbon fiber-diatomite composite filler; The modified basalt fiber is prepared by adding deionized water and myristyl trimethyl ammonium bromide into a reaction container, heating to 60 ℃, magnetically stirring for 30min, stopping stirring, adding pretreated basalt fiber into the reaction container, fully submerging, soaking for 6h, filtering, repeatedly flushing with deionized water, drying to constant weight, obtaining an intermediate product, adding absolute ethyl alcohol and deionized water into the reaction container, mixing, adding N- (beta-aminoethyl) -gamma-aminopropyl methyl dimethoxy silane, heating to 60 ℃, magnetically stirring for 30min, adding the intermediate product into the reaction container, fully submerging, soaking for 6h, filtering, repeatedly flushing with absolute ethyl alcohol, and finally drying the final product in a drying box at 80 ℃ for 12h, thus obtaining the self-made modified basalt fiber.
  2. 2. The high-toughness high-strength concrete according to claim 1, wherein the concrete comprises, by weight, 115 parts of epoxy resin, 8 parts of absolute ethyl alcohol, 36 parts of a T31 curing agent, 36 parts of a modified carbon fiber-diatomite composite filler, 55 parts of fly ash, 8 parts of liquid nitrile rubber, 440 parts of quartz sand and 12 parts of modified basalt fiber.
  3. 3. The high-toughness high-strength concrete according to claim 1, wherein the fineness modulus of the quartz fine sand is 2.4-2.7, and the granularity is 2-5mm.
  4. 4. The high-toughness high-strength concrete according to claim 1, wherein the fly ash is class I ash, and the specific surface area is more than or equal to 350m 2 /kg.
  5. 5. The high-toughness and high-strength concrete according to claim 1, wherein the epoxy resin is bisphenol a type E44 epoxy resin.
  6. 6. The high-toughness and high-strength concrete according to claim 1, wherein the carbon fibers are chopped carbon fibers having an average diameter of 10 μm and a length of 1-2cm.
  7. 7. The high-toughness high-strength concrete according to claim 1, wherein the basalt fiber pretreatment method comprises the steps of placing basalt fibers in a muffle furnace for heat treatment, cooling the basalt fibers in a hydrochloric acid solution with the concentration of 1mol/L, heating to 80 ℃, pickling for 5 hours, filtering, repeatedly flushing the basalt fibers until the pH value of filtrate is 7, collecting the basalt fibers, and fully drying the basalt fibers to constant weight to obtain the pretreated basalt fibers.
  8. 8. The high-toughness high-strength concrete according to claim 7, wherein the heat treatment temperature of the muffle furnace is set to 500 ℃.
  9. 9. The well lid is characterized by comprising a steel reinforcement framework part and a concrete cover body filled in the steel reinforcement framework, wherein the concrete cover body is made of the high-toughness high-strength concrete according to any one of claims 1-8.
  10. 10. A method for preparing a well lid according to claim 9 is characterized by comprising the steps of sequentially adding epoxy resin, absolute ethyl alcohol, modified carbon fiber-diatomite composite filler, fly ash, liquid nitrile rubber, quartz sand and modified basalt fiber into a stirring container, uniformly stirring for 2-3min to completely mix, adding a T31 curing agent, continuously stirring for 3-5min to uniformly disperse, obtaining high-toughness high-strength concrete, placing a steel bar framework into a mold, filling the high-toughness high-strength concrete into the steel bar framework, vibrating uniformly, curing for 28h, and demolding to obtain the well lid.

Description

High-toughness high-strength concrete and well lid and preparation method thereof Technical Field The invention belongs to the technical field of concrete well covers, and particularly relates to high-toughness high-strength concrete and a well cover and a preparation method thereof. Background With the acceleration of the urban process, municipal construction is increasingly accelerated, and the number of municipal engineering facilities is rapidly increased. At every corner of a city we can find various underground pipeline manhole covers which serve a plurality of fields of telecommunications, electricity, gas, heat, fire protection and sanitation. These manhole covers are located throughout the street and alley of the city and become an integral part of the city infrastructure. However, manhole covers made of cast iron materials have been widely used in the municipal utility field for a long time in our country. The choice of such materials, although meeting to some extent the structural strength requirements, has inherent limitations such as high processing energy consumption and pollution to the environment, which have a considerable impact on engineering costs, environmental protection and energy consumption. Especially, at present, the phenomena of damage and illegal resale of the manhole cover are frequent, which not only seriously affect the normal operation of municipal facilities, but also bring serious threat to the traffic safety and personal safety of citizens, thereby causing a series of social problems and economic losses. The prior art has Chinese patent application number 202411694598.9, and discloses a high-strength concrete and well lid and a preparation method thereof, wherein the high-strength concrete and well lid comprises 475-485 parts by weight of cement, 715-725 parts by weight of coarse aggregate, 1075-1085 parts by weight of fine aggregate, 115-125 parts by weight of modified steel fiber, 9.2-9.8 parts by weight of polycarboxylate water reducer and 165-170 parts by weight of water. The core matrix in the prior art is cement, and the cement can generate self-shrinkage and drying shrinkage in the hydration process, so that micro-stress can be induced in the material, even if fiber reinforcement exists, microscopic defects or potential microcracks can be formed, and the micro-defects become starting points for the initiation and the expansion of later-stage macrocracks, so that the possibility of cracking exists after long-time application. In the prior art, steel fibers are mainly used as reinforcing materials, the steel fibers are still metal in nature, corrosion is still possible in long-term service or extremely humid and chlorine-rich environments, once corrosion occurs, the volume expansion of the steel fibers can cause internal stress, and the concrete structure is destroyed, so that the well lid loses efficacy, the steel fibers are high in density and large in specific gravity, and the steel fibers have limited possibility in application scenes with requirements on dead weight in certain application scenes. The prior art has the Chinese patent application number 201811120457.0, and discloses an epoxy resin-based composite structure manhole cover and a preparation method thereof, wherein epoxy resin is adopted as a matrix, and according to the stress characteristics of the manhole cover, a bottom layer and a surface layer of the manhole cover are respectively prepared, and basalt fiber mesh cloth is assisted in the middle to prepare the manhole cover. The structure has a certain effect on resisting integral bending in a macroscopic view, but in the service process of the well lid, the well lid is subjected to repeated impact load, temperature change and moisture erosion, stress concentration is easily generated at an interlayer interface to form a cracking source, and finally, structural delamination and damage are caused, so that the long-term reliability of the well lid is reduced. In addition, the PP fiber in the technical scheme adopted in the prior art may be not firmly combined with the matrix interface, and is easy to slip or pull out under the action of external force, so that the effects of bridging cracks and transferring stress cannot be effectively achieved. Therefore, in order to solve the technical problems, the application provides high-toughness high-strength concrete, a well lid and a preparation method thereof. Disclosure of Invention The invention aims to solve the defect problems in the technical scheme and provide high-toughness high-strength concrete, a well lid and a preparation method thereof. The application provides a high-toughness high-strength concrete, which comprises, by weight, 100-120 parts of epoxy resin, 5-10 parts of absolute ethyl alcohol, 25-40 parts of a T31 curing agent, 25-40 parts of modified carbon fiber-diatomite composite filler, 40-60 parts of fly ash, 5-10 parts of liquid nitrile rubber, 400-450 parts of quartz fine sand and 5-