阅读说明：本技术 一种轻质多孔碳酸钙材料及其制备方法 (Light porous calcium carbonate material and preparation method thereof ) 是由 赵阳 金浪 史亚杰 于 2018-07-09 设计创作，主要内容包括：本发明公开了一种轻质多孔碳酸钙材料及其制备方法,所述轻质多孔碳酸钙材料,使用胶凝材料及无机掺合料的组合,气硬反应后材料主要成分为碳酸钙,相较常见的水泥基轻质多孔混凝土材料,由于其原料的矿物组份单一,且在养护阶段材料反应程度高,在抗碳化性能、龄期内力学性能稳定性、温度耐受性等性能方面得到提升。通过各功能组份(稳泡剂、减水剂、调凝剂、防水剂、抗开裂组份等)含量的调整,可实现材料性能及工艺稳定性的调整。该材料具有较低的侵彻强度和密度,以及特定的压溃吸能的力学特征,可以用于机场跑道端特性材料拦阻系统中的应用。(The invention discloses a lightweight porous calcium carbonate material and a preparation method thereof, the lightweight porous calcium carbonate material uses the combination of a cementing material and an inorganic admixture, the main component of the material after the gas hardening reaction is calcium carbonate, compared with the common cement-based lightweight porous concrete material, the material has single mineral component and high reaction degree in the curing stage, and the performances such as carbonization resistance, mechanical property stability in the age, temperature tolerance and the like are improved. The adjustment of the material performance and the process stability can be realized by adjusting the contents of various functional components (foam stabilizer, water reducer, coagulation regulator, waterproofing agent, anti-cracking component and the like). The material has low penetration strength and density and specific mechanical characteristics of crushing and energy absorption, and can be applied to a characteristic material arresting system at an airport runway end.)

1. The lightweight porous calcium carbonate material is characterized by being prepared from the following raw materials in parts by weight:

wherein the cementing material is at least one of slaked lime or quicklime, and the inorganic admixture is at least one of calcium carbonate or siliceous admixture.

2. The lightweight porous calcium carbonate material according to claim 1, characterized in that the porous calcium carbonate material is prepared from raw materials comprising, in parts by weight:

3. the lightweight porous calcium carbonate material according to claim 1, characterized in that:

the siliceous blending material is at least one of silica fume, mineral powder or fly ash.

4. The lightweight porous calcium carbonate material according to claim 1, characterized in that:

the foaming agent is hydrogen peroxide, and the concentration of the hydrogen peroxide is 15-70%, preferably 30-50%.

5. The lightweight porous calcium carbonate material according to claim 1, characterized in that:

the foam stabilizer is at least one of sodium dodecyl sulfate, fatty alcohol-polyoxyethylene ether sodium sulfate, alpha-alkenyl sodium sulfonate, calcium stearate, aluminum stearate, silicone amide, cellulose ether or starch ether.

6. The lightweight porous calcium carbonate material according to claim 1, characterized in that:

the water reducing agent is at least one of a polycarboxylic acid water reducing agent, a melamine water reducing agent or a lignosulfonate water reducing agent.

7. The lightweight porous calcium carbonate material according to claim 1, characterized in that:

the set adjusting agent is at least one of aluminum sulfate, high-alumina cement, sulphoaluminate cement and portland cement.

8. The lightweight porous calcium carbonate material according to claim 1, characterized in that the porous calcium carbonate material comprises at least one of the following components, based on 100 parts by weight of cementitious material:

1-10 parts of a waterproof agent; preferably 4-8 parts;

0.3-2 parts of an anti-cracking component; preferably 0.5 to 1.5 parts.

9. The lightweight porous calcium carbonate material according to claim 8, characterized in that:

the waterproof agent is at least one of polymer emulsion, latex powder, organic silicon waterproof agents and stearate, and the anti-cracking component is at least one of polypropylene fibers, polyvinyl alcohol fibers, glass fibers, wollastonite fibers and sepiolite fibers.

10. A method for preparing lightweight porous calcium carbonate material according to any one of claims 1 to 9, characterized by comprising the steps of:

1) preparing slurry: weighing the raw materials according to the dosage, and mixing the raw materials except the foaming agent to obtain slurry;

2) adding a foaming agent into the slurry obtained in the step 1), and stirring and mixing to obtain pre-foamed slurry;

3) and injecting the pre-foamed slurry into a mold, and preparing the lightweight porous calcium carbonate material through foaming and curing processes.

Technical Field

The invention belongs to the field of Materials, relates to a calcium carbonate foam material and a preparation method thereof, and particularly relates to a light porous calcium carbonate material which is used for an airport runway end characteristic material Arresting System (EMAS) and can be prefabricated and formed and a preparation method thereof.

Background

Statistical data at home and abroad show that in accident signs seriously damaging civil aviation flight safety, an airplane rushes out of the head of a runway position column, and a runway end safety area is important for reducing the risk of the airplane rushing out of the runway, so that the safety of the airplane and personnel is ensured. ICAO is specified in annex 14-airport: a meter runway with reference code 1 or 2 and a runway with reference code 3 or 4, a runway end safety zone must be set. The length of the runway end safety zone should not extend from the lifting belt outwardly less than 90m, preferably up to 240 m. However, due to restrictions of geography or other environmental factors, many airports have difficulty in meeting the length requirement of a new runway end safety area, and great flight safety accident potential is caused. Considering the possible serious consequences caused by the airplane rushing out of the runway, EMAS system research is carried out at home and abroad. The EMAS absorbs the kinetic energy of the airplane by utilizing the collapse of an EMAS characteristic material (generally a light foam material) under the rolling action of the tire of the airplane, gradually decelerates the airplane and finally stops the airplane at a preset distance on the premise of ensuring the safety of the structure of the airplane and passengers, and avoids the catastrophic consequences caused by the fact that the airplane rushes out of a runway and enters dangerous terrains (cliffs, water areas and the like). Currently, EMAS is applied to a plurality of airports in the United states and multinational airports including China, and is an effective means for improving safety guarantee margin of the airports, and 11 airplanes are successfully stopped.

The blocking function of the EMAS mainly depends on the crushing energy-absorbing characteristic of a characteristic material, and the most important parameters of the effective blocking performance of the system are calculated in the mechanical properties (such as the compressive strength under the penetration condition, the crushable depth and the like) of the characteristic material in the EMAS design. The overlarge compressive strength can cause the blocking resistance and deceleration of the airplane to be overlarge in the blocking process, thus easily causing the structural damage of the airplane and the injury and death of the personnel on the airplane; the blocking performance of the EMAS system is poor due to the fact that the compressive strength is too small and the blocking force borne by the airplane is small. Therefore, in order to ensure the use safety of the EMAS system, the mechanical property of the characteristic material needs to be relatively stable in the use environment and the design life. Based on the application characteristics, the national industry standard (MH/T5111-: the stress crushing degree curve is in a three-section type, and the maximum crushing degree is not less than 0.6. Wherein the degree of crushing is the ratio of the depth of compression to the total height of the sample.

At present, the main EMAS products at home and abroad mainly use cement-based foam concrete as EMAS characteristic materials, and the concrete materials use cement (portland cement, sulphoaluminate cement, and the like) as a cementing material. Firstly, based on the characteristics that cement is mainly used in the field of building engineering, the current relevant industry standards all make individual requirements on various performances of cement, for example, in important strength indexes, the minimum value requirement is made on the strength of the cement in the 28-day age, and the strength range and the stability of the cement in the later age are not specifically required. Secondly, based on the characteristics of multi-mineral composition and complex raw material sources of cement, the performances of cement materials in different batches, different manufacturers and different storage times are all inconsistent. Further, cement as a cement has strength derived from hydration of various minerals in cement, reaction of alkali aggregate and the like, and the reaction proceeds as a continuous reaction kinetic process, and is gradually increased in strength, and it is difficult to achieve a stable state in a short time. The characteristics lead the cement-based foam concrete to have poor process stability, low yield and long maintenance period when being used as an EMAS characteristic material. Therefore, the development of the foam concrete material with single component and stable performance has great significance for improving the use effect of the EMAS and prolonging the service life of the EMAS.

Disclosure of Invention

In order to solve the problems in the prior art, the invention discloses a lightweight porous calcium carbonate material and a preparation method thereof.

The invention aims to provide a porous calcium carbonate material which is prepared from the following raw materials in parts by weight:

wherein the cementing material is at least one of hydrated lime or quicklime.

The inorganic admixture is at least one of calcium carbonate or siliceous admixture, and the siliceous admixture is preferably at least one of silica fume, mineral powder or fly ash.

The foaming agent is hydrogen peroxide, and the concentration of the hydrogen peroxide is 15-70%, preferably 30-50%.

The foam stabilizer is a foam stabilizer commonly used in the field, and preferably at least one of sodium dodecyl sulfate, sodium fatty alcohol-polyoxyethylene ether sulfate, sodium alpha-alkenyl sulfonate, calcium stearate, aluminum stearate, silicone amide, cellulose ether or starch ether.

The water reducing agent is a water reducing agent commonly used in the field, and preferably at least one of a polycarboxylic acid water reducing agent, a melamine water reducing agent and a lignosulfonate water reducing agent.

The set control agent is commonly used in the field, and preferably at least one of aluminum sulfate, high-alumina cement, sulphoaluminate cement and portland cement.

The porous calcium carbonate material can also comprise at least one of the following components in 100 parts by weight of the gelled material:

1-10 parts of a waterproof agent; preferably 4 to 8 parts

0.3-2 parts of an anti-cracking component; preferably 0.5 to 1.5 parts.

The anti-cracking component is commonly used in the field, and is preferably at least one of polypropylene fiber, polyvinyl alcohol fiber, glass fiber, wollastonite fiber and sepiolite fiber.

The waterproof agent is one commonly used in the field, and preferably at least one of polymer emulsion, latex powder, organosilicon waterproof agent and stearate.

The invention also aims to provide a preparation method of the light porous calcium carbonate material, which comprises the following steps:

1) preparing slurry: weighing the raw materials according to the dosage, and mixing the raw materials except the foaming agent to obtain slurry;

2) adding a foaming agent into the slurry obtained in the step 1), and stirring and mixing to obtain pre-foamed slurry;

3) and injecting the pre-foamed slurry into a mold, and preparing the lightweight porous calcium carbonate material through foaming and curing processes.

The foaming and curing processes are all common in the art.

Preferably, the preparation method can adopt the following steps:

1) preparing slurry: weighing the raw materials according to the dosage, slowly stirring the solid components for 30-60 s, uniformly mixing, adding the liquid components except the foaming agent into the dry mixed powder, and quickly stirring for 60-120 s to obtain slurry;

2) adding a foaming agent into the slurry, and quickly stirring and mixing for 8-10 s to obtain pre-foamed slurry;

3) injecting the pre-foamed slurry into a mold, standing and foaming for 40-70 s, and placing the foamed and molded slurry in an environment with CO₂Curing and forming for 24-48 h in a curing box with the concentration of 3-10%, the temperature of 30-50 ℃ and the humidity of 90 +/-5%; and (4) demolding, namely placing the test block in a standard cement curing room for curing for 28 days to obtain the lightweight porous calcium carbonate material.

The invention has the beneficial effects that:

1) the lightweight porous calcium carbonate material uses the combination of the cementing material and the inorganic admixture, the main component of the material is calcium carbonate after the gas hardening reaction, compared with the common cement-based lightweight porous concrete material, the lightweight porous calcium carbonate material has the advantages that the mineral component of the raw material is single, and the material reaction degree is high in the maintenance stage.

2) Compared with the common cement-based lightweight porous concrete material, the lightweight porous calcium carbonate material has the advantages that the carbonization resistance, the stability of mechanical properties in the age period, the temperature tolerance and other properties are improved.

3) The adjustment of the material performance and the process stability can be realized by adjusting the contents of various functional components (foam stabilizer, water reducer, coagulation regulator, waterproofing agent, anti-cracking component and the like).

4) The lightweight porous calcium carbonate material can reduce the water absorption of the material by increasing the hydrophobic component, thereby improving the weather resistance of the material, such as freeze thawing resistance and the like.

5) The light porous calcium carbonate material has the following properties:

the density is 150 to 350kg/m³；

The mechanical property can meet the requirements of 'characteristic material arresting system' industry standard (MH/T5111-2015), and the penetration compressive strength is 0.1-0.6 MPa, preferably 0.2-0.45 MPa, and more preferably 0.3-0.4 MPa; a maximum degree of crushing of greater than 60%, preferably greater than 70%;

the flame retardant property meets the requirements of 'characteristic material arresting system' industry standard (MH/T5111-2015), and meets the A-grade requirements of GB/T8624-2012;

the freeze-thaw resistance meets the requirements of the industry standard (MH/T5111-2015) of the characteristic material arresting system, the mass loss rate is not more than 5 percent after 25 freeze-thaw cycles, and the freezing resistance coefficient is within the range of 0.8-1.2.

Drawings

FIG. 1 is a stress-strain curve of the porous calcium carbonate foam of example 2 compressed by a compression bar having a ram diameter of 50.8mm and a penetration speed of 500 mm/min.

Detailed Description

The raw materials used in the examples of the present invention are all commercially available products.