Carbon-polyethylene hybrid fiber EGC material and preparation method thereof

Abstract

The invention belongs to the field of civil engineering materials and preparation, and particularly relates to a carbon-polyethylene hybrid fiber EGC material and a preparation method thereof. Comprising the following components: slag, fly ash, quartz sand, barium chloride, water, sodium hydroxide, sodium silicate, carbon fibers and PE fibers. A large amount of solid waste slag and fly ash are used as gel materials, the use amount of ordinary Portland cement is reduced, production energy consumption and environmental pollution are reduced, and the method is green and environmentally friendly. The prepared composite material has the advantages of high density, compact microstructure bridging, high crack initiation strength and high ductility. The invention can be used in the fields of expressway expansion joints, coupling beams, external wall insulation boards and the like by utilizing the characteristics.

Description

Technical Field

[0001] The invention belongs to the field of civil engineering materials and preparation thereof, and in particular relates to a carbon-polyethylene hybrid fiber EGC material and a preparation method thereof. Background Art

[0002] High-ductility fiber-reinforced geopolymer composites (Engineered Geopolymer Composites, EGC for short) are high-performance materials designed based on microscopic fracture theory. They exhibit multi-crack cracking and strain hardening characteristics under tension-bending loads. Their ductility can reach hundreds of times that of traditional concrete, dozens of times that of ordinary FRC, and several times that of steel bars. They are known as "bendable concrete". At the same time, EGC can control the crack width under extreme load to below 80μm and has self-healing ability. Therefore, the promotion and application of EGC can greatly improve the anti-penetration performance, anti-cracking ability and seismic performance of concrete structures. At present, this material with excellent performance has been used in the fields of highway expansion joints, connecting beams, exterior wall insulation panels, etc.

[0003] However, the tensile properties of the geopolymer matrix itself are poor, resulting in low cracking strength of EGC and easy initial cracks. Therefore, the tensile strength of EGC materials can be improved by mixing fibers. In addition, there is a certain mixing effect of fiber mixing, which can improve the mechanical properties of a single fiber, give full play to the advantages of multiple fibers, and achieve complementary advantages. Mixing carbon fiber and polyethylene fiber can achieve a synergistic bridging mechanism under different crack widths. Summary of the invention

[0004] 1. In order to solve the above problems, the present invention provides a carbon-polyethylene hybrid fiber EGC material and a preparation method thereof, which has good mechanical properties and promotes the application of high-performance EGC materials in construction projects. To achieve this purpose, the carbon-polyethylene hybrid fiber EGC material of the present invention includes the following components in mass fractions: slag: 338 parts, fly ash: 225 parts, quartz sand: 192 parts, barium chloride: 6 parts, water: 90 parts, sodium hydroxide: 20 parts, sodium silicate: 219 parts, carbon fiber: 2.85 parts, PE fiber: 10 parts.

[0005] 2. Preferably, the slag is blast furnace S105 slag.

[0006] 3. Preferably, the fly ash is Class F fly ash.

[0007] 4. Preferably, the quartz sand has a particle size of about 76um-150um and a density of 2.65g / cm 3 of quartz sand.

[0008] 5. Preferably, the PE fiber is an ultra-high molecular weight polyethylene fiber with a single fiber length of 12 mm and a diameter of 24 μm.

[0009] 6. Preferably, the carbon fiber is Japanese Toray chopped 6mm carbon fiber, T700-12k, with a tensile strength of 4900Mpa and a diameter of 7μm.

[0010] 7. A method for preparing a carbon-polyethylene hybrid fiber EGC material, comprising the following steps:

[0011] Step 1: first dissolve the sodium hydroxide solid and mix it with the sodium silicate solution to form an alkaline excitation solution;

[0012] Step 2: First, put slag, fly ash and quartz sand into a mortar planetary mixer and stir at low speed for 3 minutes;

[0013] Step 3: Slowly pour the alkaline excitation solution, stir at low speed for 2 minutes, then stir at high speed for 1 minute.

[0014] Step 4: Evenly sprinkle PE and carbon fiber within 2 minutes, and then stir at high speed for 1 minute to obtain carbon-polyethylene hybrid fiber EGC material.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The present invention uses a large amount of solid waste slag and fly ash as gel material, which reduces the use of ordinary Portland cement, reduces production energy consumption and environmental pollution, and is green and environmentally friendly.

[0017] 2. The composite material prepared by the present invention has the advantages of high density, tight microstructure bridging, high cracking strength and high ductility.

[0018] 3. The present invention can be used in the fields of highway expansion joints, connecting beams, exterior wall insulation panels, etc. by utilizing its characteristics. DETAILED DESCRIPTION

[0019] In order to more fully explain the implementation of the present invention, the present invention is further described below in conjunction with specific embodiments. The examples are only used to explain the present invention, rather than to limit the scope of the present invention.

[0020] The carbon-polyethylene hybrid fiber EGC material includes the following components: slag: 338 parts, fly ash: 225 parts, quartz sand: 192 parts, barium chloride: 6 parts, water: 90 parts, sodium hydroxide: 20 parts, sodium silicate: 219 parts, carbon fiber: 2.85 parts, and PE fiber: 10 parts.

[0021] Example 1

[0022] The geopolymer mix ratio is as follows:

[0023] Table 1

[0024] slag Fly ash Quartz sand Barium chloride Sodium hydroxide Sodium silicate PE fiber water 338 225 192 6 20 219 10 90

[0025] Preparation method

[0026] Step 1: first dissolve the sodium hydroxide solid and mix it with the sodium silicate solution to form an alkaline excitation solution;

[0027] Step 2: First, put slag, fly ash and quartz sand into a mortar planetary mixer and stir at low speed for 3 minutes;

[0028] Step 3: Slowly pour the alkaline excitation solution, stir at low speed for 2 minutes, and then stir at high speed for 1 minute;

[0029] Step 4: Sprinkle the PE fiber evenly within 2 minutes, and then stir at high speed for 1 minute.

[0030] According to the above steps, PE fiber EGC material is obtained.

[0031] Example 2

[0032] The foaming polymer formula is as follows:

[0033] Table 2

[0034] slag Fly ash Quartz sand Barium chloride Sodium hydroxide Sodium silicate Carbon Fiber PE fiber water 338 225 192 6 20 219 0.95 10 90

[0035] Preparation method

[0036] Step 1: first dissolve the sodium hydroxide solid and mix it with the sodium silicate solution to form an alkaline excitation solution;

[0037] Step 2: First, put slag, fly ash, silica fume and No. 9 sand into a mortar planetary mixer and stir at low speed for 3 minutes;

[0038] Step 3: Slowly pour the alkali-activated solution and styrene-acrylic emulsion into the mixture, stirring at low speed for 2 minutes, and then stirring at high speed for 1 minute;

[0039] Step 4: Sprinkle carbon fiber and PE fiber evenly within 2 minutes, and then stir at high speed for 1 minute.

[0040] According to the above steps, the hybrid fiber ECC material can be finally obtained.

[0041] Example 3

[0042] The foaming polymer formula is as follows:

[0043] Table 3

[0044] slag Fly ash Quartz sand Barium chloride Sodium hydroxide Sodium silicate Carbon Fiber PE fiber water 338 225 192 6 20 219 1.43 10 90

[0045] Preparation method

[0046] Step 1: first dissolve the sodium hydroxide solid and mix it with the sodium silicate solution to form an alkaline excitation solution;

[0047] Step 2: First, put slag, fly ash, silica fume and No. 9 sand into a mortar planetary mixer and stir at low speed for 3 minutes;

[0048] Step 3: Slowly pour the alkali-activated solution and styrene-acrylic emulsion into the mixture, stirring at low speed for 2 minutes, and then stirring at high speed for 1 minute;

[0049] Step 4: Sprinkle carbon fiber and PE fiber evenly within 2 minutes, and then stir at high speed for 1 minute.

[0050] According to the above steps, the hybrid fiber ECC material can be finally obtained.

[0051] Example 4

[0052] The foaming polymer formula is as follows:

[0053] Table 4

[0054] slag Fly ash Quartz sand Barium chloride Sodium hydroxide Sodium silicate Carbon Fiber PE fiber water 338 225 192 6 20 219 2.85 10 90

[0055] Preparation method

[0056] Step 1: first dissolve the sodium hydroxide solid and mix it with the sodium silicate solution to form an alkaline excitation solution;

[0057] Step 2: First, put slag, fly ash, silica fume and No. 9 sand into a mortar planetary mixer and stir at low speed for 3 minutes;

[0058] Step 3: Slowly pour the alkali-activated solution and styrene-acrylic emulsion into the mixture, stirring at low speed for 2 minutes, and then stirring at high speed for 1 minute;

[0059] Step 4: Sprinkle carbon fiber and PE fiber evenly within 2 minutes, and then stir at high speed for 1 minute.

[0060] According to the above steps, the hybrid fiber ECC material can be finally obtained.

[0061] Example 5

[0062] The foaming polymer formula is as follows:

[0063] Table 5

[0064] slag Fly ash Quartz sand Barium chloride Sodium hydroxide Sodium silicate Carbon Fiber PE fiber water 338 225 192 6 20 219 3.8 10 90

[0065] Preparation method

[0066] Step 1: first dissolve the sodium hydroxide solid and mix it with the sodium silicate solution to form an alkaline excitation solution;

[0067] Step 2: First, put slag, fly ash, silica fume and No. 9 sand into a mortar planetary mixer and stir at low speed for 3 minutes;

[0068] Step 3: Slowly pour the alkali-activated solution and styrene-acrylic emulsion into the mixture, stirring at low speed for 2 minutes, and then stirring at high speed for 1 minute;

[0069] Step 4: Sprinkle carbon fiber and PE fiber evenly within 2 minutes, and then stir at high speed for 1 minute.

[0070] According to the above steps, the hybrid fiber ECC material can be finally obtained.

[0071] For the specimens formed according to the above-mentioned mix ratio, preparation method and curing system, the tensile strength at 28 days was measured according to the requirements of the Japan Society of Civil Engineers (JSCE). The tensile strain test results are shown in Table 6.

[0072] Table 6:

[0073] Crack tensile strength / MPa Ultimate tensile strength / MPa Ultimate strain / % Example 1 2.68 5.67 6.34 Example 2 2.95 6.32 6.93 Example 3 3.21 6.53 7.01 Example 4 3.56 7.02 7.16 Example 5 4.02 6.45 6.42

[0074] It can be seen from Table 6 that the cracking strength and ultimate strain of hybrid fiber ECC can be significantly enhanced by optimizing the carbon fiber content. The best effect is achieved when the carbon fiber content is 0.3%. When the carbon fiber content is increased, the cracking strength will increase, but the ultimate strain and ultimate tensile strength will decrease.

[0075] The above description is only a preferred embodiment of the present invention and does not constitute any other form of limitation to the present invention. Any modification or equivalent change made based on the technical essence of the present invention still falls within the scope of protection required by the present invention.

Claims

1. Carbon-polyethylene hybrid fiber EGC material, characterized in that: The invention comprises the following components: slag, fly ash, quartz sand, barium chloride, water, sodium hydroxide, sodium silicate, carbon fiber and PE fiber. The slag, fly ash and silica ash constitute a cementitious material. The mixing ratio of each component is designed as follows: by mass fraction: 338 parts of slag, 225 parts of fly ash, 192 parts of quartz sand, 6 parts of barium chloride, 90 parts of water, 20 parts of sodium hydroxide, 219 parts of sodium silicate, 2.85 parts of carbon fiber and 10 parts of PE fiber.

2. The carbon-polyethylene hybrid fiber EGC material according to claim 1, characterized in that: The slag is blast furnace S105 slag.

3. The carbon-polyethylene hybrid fiber EGC material according to claim 1, characterized in that: The fly ash is Class F fly ash.

4. The carbon-polyethylene hybrid fiber EGC material according to claim 1, characterized in that: The No. 9 sand has a particle size of about 76um-150um and a density of 2.65g / cm 3 of quartz sand.

5. The carbon-polyethylene hybrid fiber EGC material according to claim 1, characterized in that: The PE fiber is an ultra-high molecular weight polyethylene fiber, with a single fiber length of 12 mm and a diameter of 24 μm.

6. The carbon-polyethylene hybrid fiber EGC material according to claim 1, characterized in that: The carbon fiber is Japanese Toray chopped 6mm carbon fiber, T700-12k, with a tensile strength of 4900Mpa and a diameter of 7μm.

7. The specific steps are as follows: A method for preparing a lightweight foamed fiber geopolymer-based composite material comprises the following steps: Step 1: first dissolve the sodium hydroxide solid and mix it with the sodium silicate solution to form an alkaline excitation solution; Step 2: First, put slag, fly ash, silica fume and No. 9 sand into a mortar planetary mixer and stir at low speed for 3 minutes; Step 3: Slowly pour the alkali-activated solution and styrene-acrylic emulsion into the mixture, stir at low speed for 2 minutes, then at high speed for 1 minute. Step 4: Evenly sprinkle the carbon fiber and polyethylene fiber within 2 minutes, and then stir at high speed for 1 minute to obtain a carbon-polyethylene hybrid fiber EGC material.