A kind of crack-resistant green carbon-reducing plain concrete

Abstract

The present application discloses a crack-resistant green carbon-reducing plain concrete, which comprises the following components by mass: 100 parts of cement, 110 to 140 parts of sand, 180 to 220 parts of crushed stone, 8 to 12 parts of fly ash, 2 to 10 parts of admixtures and 30 to 40 parts of water; and has the advantage of improving crack resistance.

Description

Technical Field

[0001] The invention relates to crack-resistant green carbon-reducing plain concrete. Background Art

[0002] Architectural concrete is a type of concrete that is cast in one go without any surface decoration. The concrete surface itself or the surface treated with transparent protective materials is used as the architectural decoration surface. Fair-faced concrete not only highlights the simple and natural artistic beauty of concrete, but also does not require too much surface decoration, which greatly saves resources and costs. It conforms to the concept of environmental protection and energy saving, making the construction of fair-faced concrete projects gradually popular in China. At the same time, due to the large-scale promotion and application of fair-faced concrete projects, many scholars have gradually initiated research on the quality control and evaluation of fair-faced concrete.

[0003] The biggest difference between plain concrete and ordinary concrete is that plain concrete does not have the protective layer of decorative materials on the surface of ordinary concrete and is exposed to the external environment for a long time. It is directly corroded by the external environment and will crack. This puts forward more stringent requirements on the durability of plain concrete. Therefore, it is of certain production and application value to develop a plain concrete with high crack resistance. Summary of the invention

[0004] The invention aims to provide a crack-resistant green carbon-reducing plain concrete, which has the advantage of improving the crack resistance.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions: A crack-resistant green carbon-reducing plain concrete is characterized in that, calculated by weight, it comprises the following components: 100 parts of cement, 110-140 parts of sand, 180-220 parts of crushed stone, 8-12 parts of fly ash, 2-10 parts of admixtures and 30-40 parts of water.

[0006] Furthermore, the admixture includes cycloalkane oil, PEO-PPO-PEO triblock copolymer and n-butyldimethylsilane, and the mass ratio of cycloalkane oil, PEO-PPO-PEO triblock copolymer and n-butyldimethylsilane is 1:0.3-0.5:0.15-0.25.

[0007] Further, the following components are included: 100 parts of cement, 125 parts of sand, 200 parts of crushed stone, 10 parts of fly ash, 4 parts of naphthenic oil, 1.6 parts of PEO-PPO-PEO triblock copolymer, 0.8 parts of n-butyldimethylsilane and 35 parts of water.

[0008] Furthermore, the invention comprises the following components: 100 parts of cement, 125 parts of sand, 200 parts of crushed stone, 10 parts of fly ash, 4 parts of cyclohexane oil, 1.6 parts of PEO-PPO-PEO triblock copolymer, 0.8 parts of n-butyldimethylsilane, 35 parts of water, 0.3-0.5 parts of polypropylene powder, 0.1-0.3 parts of polycarboxylic acid water reducer, and 0.4-0.6 parts of nano silicon dioxide.

[0009] Furthermore, the following components are included: 100 parts of cement, 125 parts of sand, 200 parts of crushed stone, 10 parts of fly ash, 4 parts of cyclohexane oil, 1.6 parts of PEO-PPO-PEO triblock copolymer, 0.8 parts of n-butyldimethylsilane, 35 parts of water, 0.4 parts of polypropylene powder, 0.2 parts of polycarboxylic acid water reducer, and 0.5 parts of nano silicon dioxide.

[0010] The technical effects of the present invention are mainly reflected in the following aspects: By adding fly ash to concrete to replace part of the cement, the fluidity of the concrete is significantly improved. At the same time, cycloalkane oil, PEO-PPO-PEO triblock copolymer and n-butyl dimethyl silane are added thereto. Cycloalkane oil and PEO-PPO-PEO triblock copolymer assist the dispersion of n-butyl dimethyl silane. The action of n-butyl dimethyl silane and cement improves the problem of pores and a large number of pores on the surface of concrete, thereby improving its impermeability and crack resistance. Polypropylene micropowder and nano-silica can be further filled into the concrete to improve its mechanical properties while improving its crack resistance, giving it better durability. DETAILED DESCRIPTION

[0011] In the embodiments of the present application, ordinary Portland cement with a strength grade of 42.5 MPa is selected as cement, natural sand Class II medium sand is selected as sand, the crushed stone particle size is 5-10 mm, fly ash is Class F II fly ash produced by Mawan Power Plant, cyclohexane oil is purchased from Hengshui Aoda Chemical Rubber Co., Ltd., PEO-PPO-PEO triblock copolymer is purchased from Sigma-Aldrich F127 type, polypropylene micropowder is purchased from Lubrizol of Germany, and polycarboxylic acid-based water reducer is purchased from Tuoda New Materials Technology Industry Group Co., Ltd.

[0012] Example 1: A crack-resistant green carbon-reducing plain concrete is prepared by the following method: 100 parts by mass of cement, 110 parts by mass of sand, 180 parts by mass of crushed stone and 8 parts by mass of fly ash are put into a concrete mixer and stirred evenly. Then 30 parts by mass of water, 4 parts of cyclohexane oil, 1.6 parts of PEO-PPO-PEO triblock copolymer and 0.8 parts of n-butyldimethylsilane are added into the mixer, mixed and formed, and the concrete product is obtained by demolding and curing.

[0013] Example 2: A crack-resistant green carbon-reducing plain concrete is prepared by the following method: 100 parts by mass of cement, 140 parts by mass of sand, 220 parts by mass of crushed stone and 12 parts by mass of fly ash are put into a concrete mixer and stirred evenly. Then 40 parts by mass of water, 4 parts of cyclohexane oil, 1.6 parts of PEO-PPO-PEO triblock copolymer and 0.8 parts of n-butyldimethylsilane are added into the mixer, mixed and formed, and the concrete product is obtained after demolding and curing.

[0014] Example 3: A crack-resistant green carbon-reducing plain concrete is prepared by the following method: 100 parts by mass of cement, 125 parts by mass of sand, 200 parts by mass of crushed stone and 10 parts by mass of fly ash are put into a concrete mixer and stirred evenly. Then 35 parts by mass of water, 4 parts of cyclohexane oil, 1.6 parts of PEO-PPO-PEO triblock copolymer and 0.8 parts of n-butyldimethylsilane are added into the mixer, mixed and formed, and the concrete product is obtained by demolding and curing.

[0015] Example 4: A crack-resistant green carbon-reducing plain concrete is prepared by the following method: 100 parts by mass of cement, 125 parts by mass of sand, 200 parts by mass of crushed stone and 10 parts by mass of fly ash are put into a concrete mixer and stirred evenly; then 35 parts by mass of water, 4 parts of cyclohexane oil, 1.6 parts of PEO-PPO-PEO triblock copolymer, 0.8 parts of n-butyldimethylsilane, 0.3 parts of polypropylene micropowder, 0.1 parts of polycarboxylic acid water reducing agent and 0.4 parts of nano-silica are added into the mixer, mixed and formed, and the concrete product is obtained by demolding and curing.

[0016] Example 5: A crack-resistant green carbon-reducing plain concrete is prepared by the following method: 100 parts by mass of cement, 125 parts by mass of sand, 200 parts by mass of crushed stone and 10 parts by mass of fly ash are put into a concrete mixer and stirred evenly; then 35 parts by mass of water, 4 parts of cyclohexane oil, 1.6 parts of PEO-PPO-PEO triblock copolymer, 0.8 parts of n-butyldimethylsilane, 0.5 parts of polypropylene micropowder, 0.3 parts of polycarboxylic acid water reducing agent and 0.6 parts of nano-silica are added into the mixer, mixed and formed, and then the concrete product is obtained by demolding and curing.

[0017] Example 6: A crack-resistant green carbon-reducing plain concrete is prepared by the following method: 100 parts by mass of cement, 125 parts by mass of sand, 200 parts by mass of crushed stone and 10 parts by mass of fly ash are put into a concrete mixer and stirred evenly; then 35 parts by mass of water, 4 parts of cyclohexane oil, 1.6 parts of PEO-PPO-PEO triblock copolymer, 0.8 parts of n-butyldimethylsilane, 0.4 parts of polypropylene micropowder, 0.2 parts of polycarboxylic acid water reducing agent and 0.5 parts of nano-silica are added into the mixer, mixed and formed, and the concrete product is obtained by demolding and curing.

[0018] Performance Testing (1) Anti-seepage performance test Permeability: According to the provisions of GB / T50082-2009, standard test pieces were made. After 28 days of standard curing, the test pieces were taken out and the surface was dried. Then a layer of melted sealing material was applied on the side. Then, the test pieces were pressed into the test piece sleeve heated in the oven on the spiral pressure device. After cooling slightly, the pressure can be released and the test piece sleeve is placed on the permeability tester for testing. The water pressure starts from 0.1MPa and increases by 0.1MPa every 8 hours until it reaches 3.0MPa. The results are shown in Table 1.

[0019] Table 1 (2) Crack resistance test The square circle crack resistance test analysis was adopted. After three days of standard curing, the concrete product was transferred to an oven at 110°C to force cracking. The crack resistance test mold molded the specimen with an outer diameter of 370±1mm, an inner diameter of 300±1mm, and a height of 140±1mm. During the period, the cracking situation was observed at all times, and the crack length and width were measured with an electronic vernier caliper. The results are shown in Table 2.

[0020] Table 2 First crack time / hr 28d total crack length / mm <![CDATA[Total cracking area of 28d / mm 2 > Example 1 545 50 64.2 Example 2 538 52 66.3 Example 3 542 50 64.5 Example 4 602 30 37.1 Example 5 605 29 36.3 Example 6 639 25 28.4 (3) Drying shrinkage value test The drying shrinkage value was determined according to the provisions of GB / T50082-2009. The results are shown in Table 3.

[0021] Table 3 <![CDATA[1d drying shrinkage value / ×10 -6 > <![CDATA[14d drying shrinkage value / ×10 -6 > <![CDATA[28d drying shrinkage value / ×10 -6 > Example 1 20 131 164 Example 2 21 133 169 Example 3 20 127 158 Example 4 15 104 133 Example 5 14 101 128 Of course, the above are only typical examples of the present invention. In addition, the present invention may also have many other specific implementations. All technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the present invention.

Claims

1. A crack-resistant green carbon-reducing plain concrete, characterized in that: The composition comprises the following components by weight: 100 parts of cement, 110-140 parts of sand, 180-220 parts of crushed stone, 8-12 parts of fly ash, 2-10 parts of admixture and 30-40 parts of water.

2. The anti-cracking green carbon-reducing plain concrete according to claim 1 is characterized in that: The additive comprises cycloalkane oil, PEO-PPO-PEO triblock copolymer and n-butyldimethylsilane, and the mass ratio of cycloalkane oil, PEO-PPO-PEO triblock copolymer and n-butyldimethylsilane is 1:0.3-0.5:0.15-0.

25.

3. The anti-cracking green carbon-reducing plain concrete according to claim 2 is characterized in that: The invention comprises the following components: 100 parts of cement, 125 parts of sand, 200 parts of crushed stone, 10 parts of fly ash, 4 parts of naphthenic oil, 1.6 parts of PEO-PPO-PEO triblock copolymer, 0.8 parts of n-butyldimethylsilane and 35 parts of water.

4. The anti-cracking green carbon-reducing plain concrete according to claim 3 is characterized in that: The invention comprises the following components: 100 parts of cement, 125 parts of sand, 200 parts of crushed stone, 10 parts of fly ash, 4 parts of naphthenic oil, 1.6 parts of PEO-PPO-PEO triblock copolymer, 0.8 parts of n-butyldimethylsilane, 35 parts of water, 0.3-0.5 parts of polypropylene powder, 0.1-0.3 parts of polycarboxylic acid water reducer, 0.4-0.6 parts of nano silicon dioxide.

5. The anti-cracking green carbon-reducing plain concrete according to claim 4 is characterized in that: The invention comprises the following components: 100 parts of cement, 125 parts of sand, 200 parts of crushed stone, 10 parts of fly ash, 4 parts of cyclohexane oil, 1.6 parts of PEO-PPO-PEO triblock copolymer, 0.8 parts of n-butyldimethylsilane, 35 parts of water, 0.4 parts of polypropylene micropowder, 0.2 parts of polycarboxylic acid water reducing agent and 0.5 parts of nano silicon dioxide.

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