CN115286345B

CN115286345B - High-strength cementing material containing anti-caking agent, mould-bag concrete, and preparation and application thereof

Info

Publication number: CN115286345B
Application number: CN202211024266.0A
Authority: CN
Inventors: 倪雪峰; 庞敏; 李欢欢; 周鹣鸣; 李臻; 陈刚; 顾晓锋; 虞芪敏; 吴小琴; 张跃明; 董欢; 朱虓明; 陶后兴; 王堃
Original assignee: Shanghai Urban Construction Materials Co ltd
Current assignee: Shanghai Urban Construction Materials Co ltd
Priority date: 2022-08-25
Filing date: 2022-08-25
Publication date: 2024-04-19
Anticipated expiration: 2042-08-25
Also published as: CN115286345A

Abstract

The invention relates to the technical field of cementing materials, in particular to a high-strength cementing material for mould bag concrete, a relevant mould bag concrete and preparation and application thereof. The invention reasonably selects cement, industrial by-product gypsum, anti-caking agent and mineral admixture as raw materials, particularly the novel anti-caking agent is adopted as the anti-caking agent, the traditional coarse aggregate and the traditional fine aggregate are not used in the preparation process of the mould bag concrete, the local materials are used, the soil of construction sites is used, and under reasonable formula selection, the unconfined compressive strength of the concrete for 7 days is more than 6.5MPa, and the unconfined compressive strength for 28 days is more than 10 MPa.

Description

High-strength cementing material containing anti-caking agent, mould-bag concrete, and preparation and application thereof

Technical Field

The invention relates to the technical field of cementing materials, in particular to a high-strength cementing material for mould bag concrete, a relevant mould bag concrete and preparation and application thereof.

Background

The mould bag concrete is a protective structure formed by using a double-layer high-strength woven chemical fiber fabric to form a continuous (or independent) bag-shaped body as a flexible template and filling the concrete into the bag by a high-pressure pump. Can be used as earth and stone dam, embankment protection, bank protection and bottom protection of river, lake and coast. The thickness and shape of the grass-roots are designed according to the requirements, for example, drainage filtering points can be arranged to drain accumulated water in a slope, the units are connected in a hinge mode to adapt to uneven settlement of the slope, and turf is planted in a lattice mode to improve the environment. The method has the characteristics of flexible design, convenient construction, reliable quality, underwater construction without constructing a cofferdam and the like.

The existing mould-bag concrete is generally prepared from coarse aggregate, fine aggregate, cement and additives (such as water reducer, coagulant, air entraining agent and plastic retention agent) as raw materials, and the formula is based on the traditional concrete formula thought. However, the formula cement has large consumption and strong dependence on coarse aggregate and fine aggregate resources. At present, the price of cement is continuously increased to approximately 800 yuan/ton, coarse aggregate resources such as yellow sand, stones and the like are in shortage, and the raw material supply problem is becoming severe.

At present, various solid wastes are tried to be added into a mould bag concrete formula, for example, CN106904916A discloses mould bag solidified soil for sea-fill cofferdam, a preparation method and an application method thereof, and the mould bag solidified soil in the patent is prepared by taking waste mud, a composite flocculant, a mud structural agent and biomass fibers as raw materials. The waste slurry is formed in the slurry shield tunneling process of the earth excavation tunnel engineering or the slurry formed in the pile foundation engineering and the underground continuous wall engineering construction, and the solid waste can be effectively utilized, but in order to utilize the waste slurry, the waste slurry is required to be temporarily stored, and the waste slurry is required to be transported to a construction site during use, so that the cost is increased by increasing the storage and transportation ring joints, and the operation is inconvenient. In addition, it also requires the use of composite flocculants, mud structurants and biomass fibers, which are relatively complex in composition.

CN101456705A discloses a hydraulic mould bag concrete using industrial solid waste, which is prepared by five procedures of coarse aggregate, fine aggregate, cementing material, reinforcing fiber and water through stirring, mixing and filling into mould bags. The coarse aggregate is steel slag or tailings, the fine aggregate is tailing sand or fly ash coarse slag or river sand, the traditional mould bag concrete formula thought is still adopted, coarse aggregate and fine aggregate are needed, and the coarse aggregate and the fine aggregate cannot be obtained locally. For the river bank dike, river sand/river sand can be obtained locally, but the problem of increasingly exhausting river sand/river sand resources is also faced.

CN105130293a discloses a method for preparing novel ecological bank protection material, the raw materials comprise 129-133 parts of water, 206-213 parts of cement, 52-53 parts of fly ash, 647-653 parts of sand, 1330-1342 parts of stone, 2.06-2.13 parts of water reducing agent and 0.015-0.016 part of air entraining agent, and the materials suitable for river bank slope protection are prepared by using silt and water in river channels as raw materials and assisting with materials such as broken stone or coarse sand and cement. Although a certain amount of fly ash solid waste is added in the patent, coarse aggregate and fine aggregate are required to be used, and raw material acquisition is still limited.

CN106242482a discloses a high-fluidity hydraulic filling sea mud anti-seepage curing material and a preparation method thereof, and the material consists of a component A and a component B: the component A consists of the following components: 30-60 parts of active inorganic mineral; 10-30 parts of cementing material; 10-20 parts of industrial byproduct gypsum; 5-12 parts of instant water glass; 2-5 parts of quicklime; 1-3 parts of stabilizer; each component in the component A is in a finely ground powder form, and the water content is less than or equal to 1%. The inorganic mineral contains solid wastes such as steel slag, slag and the like, and industrial byproduct gypsum is added, but the water content of all raw materials is strictly controlled.

In view of the above, conventional concrete in form bags requires a large amount of coarse aggregate, fine aggregate and cement, and although there have been studies on the addition of reinforcing wastes, the addition of coarse aggregate and fine aggregate is still required in many cases, and thus, the materials cannot be obtained in situ sufficiently. In addition, the control of the water content of the raw material requires a step such as drying, and the energy consumption is large.

Disclosure of Invention

In view of the above, on the one hand, the invention aims to provide a cementing material, in particular to a high-strength cementing material for mould bag concrete, which can ensure the strength of the material while mixing solid waste and reducing the cement dosage through reasonably selecting raw materials, and particularly, the cementing material can be particularly suitable for being combined with shoreside soil to prepare the mould bag concrete meeting engineering requirements of slope protection, bank protection, dyke fixing, sea filling, cofferdam, field building and the like.

In another aspect, the present invention is directed to a form concrete which does not use conventional coarse aggregate and fine aggregate and greatly reduces the amount of cement used.

In the use scenes of slope protection, bank protection, dyke fixation and the like of rivers, lakes and seas, the soil resources on the bank side almost do not need to be mined, transported and stored, and can be used along with digging. However, if the coarse aggregate and the fine aggregate are replaced with soil on the shore side, the strength tends to be greatly reduced. Therefore, the invention aims to enable the local materials to be obtained when the mould bag concrete is prepared through reasonable formulation, and the soil of the construction site is directly used as the raw material.

In order to achieve the above purpose, in one aspect, the present invention provides the following technical solutions:

a cementing material for mould-bag concrete, which comprises cement, industrial by-product gypsum, an anti-caking agent and a mineral additive; wherein the anti-caking agent only comprises a dispersing component and does not comprise a functional component, and the dispersing component is an inert component and does not react with water; the functional component is a water reactive component.

For performance, the cement comprises the following raw materials in percentage by weight: 15-30% of cement, 20-35% of industrial byproduct gypsum, 10-20% of anti-caking agent and 35-45% of mineral additive. The contents according to the invention are all percentages by weight, unless otherwise specified, and the contents of the individual components add up to 100%.

In one embodiment, the cement is divided into a material a and a material B, wherein the material a comprises cement, mineral admixture; the material B contains industrial by-product gypsum and anti-caking agent. Further, the mass ratio of the material A to the material B is 3:1 to 1:2, preferably 2:1 to 1.2:1, and most preferably 1.5:1.

Further, the mineral additive is selected from one or more of copper slag powder, phosphorus slag powder, fly ash, steel slag, natural zeolite and silica fume, and mineral powder is preferred. The industrial byproduct gypsum is selected from one or more of desulfurized gypsum, phosphogypsum, titanium gypsum, fluorine gypsum, citric acid gypsum and salt gypsum.

Further, the anti-caking agent only comprises a dispersing component and does not comprise a functional component, wherein the dispersing component is an inert component and does not react with water; the functional component is a water reactive component. Further, the anti-caking agent according to the present invention does not comprise free calcium oxide and free magnesium oxide.

In one embodiment, the dispersing component is selected from one or more of a lightweight porous material, a mesoporous material. Further, the lightweight porous material is selected from diatomaceous earth. The mesoporous material is selected from mesoporous carbon or mesoporous silicon. Further, the fineness of the lightweight porous material is 500 mesh or more, preferably 600 mesh, 800 mesh, 900 mesh or 1000 mesh or more. The fineness of the mesoporous material is more than 500 meshes, preferably more than 600 meshes, 800 meshes, 900 meshes or 1000 meshes.

In one embodiment, the dispersing component is selected from one or more of quartz powder, bentonite, kaolin, heavy calcium carbonate, light calcium carbonate, and silica fume. The above components of the present invention may be prepared by themselves or may be obtained from commercial sources, such as by the chemical industry of the ridge, ke Mi Ou, guo Yao, shengmai, etc.

Further, the fineness of the dispersed component is 200 mesh or more, preferably 300 mesh or more. The preferred fineness is not exactly the same because of the differences in physical properties of the individual dispersed components. For example, the fineness of the quartz powder is 400 mesh or more, preferably 500 mesh, 600 mesh or 800 mesh or more. For light calcium carbonate, the fineness is more than 200 meshes, preferably more than 300 meshes. The fineness of the heavy calcium carbonate is more than 300 meshes, preferably more than 400 meshes. For kaolin, the fineness is above 600 meshes, preferably above 800 meshes, 900 meshes or 1000 meshes. The fineness of the micro silicon powder is more than 500 meshes, preferably more than 800 meshes.

In one embodiment, a method of making a cementitious material is provided comprising the steps of: (1) Premixing industrial byproduct gypsum and an anti-caking agent to obtain a premix; (2) mixing the premix with cement and mineral admixture.

In another embodiment, a method of making a cementitious material is provided comprising the steps of: (1) mixing cement and mineral admixture to obtain a material A; (2) Premixing industrial byproduct gypsum and an anti-caking agent to obtain a material B; (3) mixing the material A and the material B.

The invention also relates to the use of the above cement, i.e. for the preparation of mould-bag concrete.

The invention also relates to a mould bag concrete which comprises the cementing material, soil and water. The cement is described in detail above, and will not be described again here.

Of course, if the industrial by-product gypsum used is free of water, an anti-agglomerating agent may not be used, in which case the form concrete contains cement, soil, water; wherein the cementing material comprises cementing material, soil and water; wherein the cementing material comprises the following raw materials in percentage by weight: 15-30% of cement, 20-35% of industrial byproduct gypsum and 35-45% of mineral additive. The total content of each component is 100%. That is, the aforementioned embodiment can be selected and used when the water content of the industrial by-product gypsum is low, for example, 1% or less, or the use of the anti-caking agent can be completely omitted, and only the amounts of the components need to be appropriately adjusted.

Further, the available local soil is advantageous to the cost, and the construction site soil is specifically selected; preferably shoreside earth. Further preferably coastal earth, lake coastal earth, river coastal earth. For example, mould bag concrete is manufactured at the coast, and the soil at the coast is directly used as solidified soil; for example, mould bag concrete is manufactured at the river side, and then the soil at the river side is directly used as solidified soil; for example, mould bag concrete is manufactured at the lake side, and then the soil at the lake side is directly used as solidified soil; and so on.

Further, the soil moisture content is 10% -40%, preferably 15% -30%, and further preferably 20% -25%. Further, the weight ratio of the soil, the cementing material and the water is as follows: cementing material: water=1400-1800:400-800:650-800, at which ratio it is advantageous to improve the concrete performance of the bag.

Further, the amount of the cementing material is 35% -50% of the soil, so that sufficient strength can be ensured. Preferably 36%, 37%, 38%, 39% or more; preferably 49%, 48%, 47%, 46%, 45% or less; most preferably 40%.

Preferably, the form concrete should meet one or more of the following conditions: (1) the mobility of the sand is 130-160mm; (2) the expansion degree is not less than 500mm; (3) curing time is 15-30h; (4) The 7-day unconfined compressive strength is above 6.5MPa, preferably above 7.5MPa, further preferably above 8.5MPa, such as up to 11MPa; (5) The 28-day unconfined compressive strength is more than 10MPa, preferably more than 15 MPa. Most preferably, each condition is satisfied.

The invention also provides a preparation method of the mould bag concrete, which specifically comprises the following steps: the raw materials comprising cementing material, construction site soil (such as shoreside soil) and water are stirred and mixed, and are injected into a mould bag. Further, a three-point pumping method is adopted. Further, the mould bags are 10-20 m long, 5-15 m wide and 10-30 cm thick.

The invention provides application of mould bag concrete, which is used in projects such as slope protection, bank protection, dyke fixing, sea filling, cofferdam, field making and the like.

Advantageous effects

Compared with the prior art, the technical scheme provided by the invention has the following remarkable effects:

(1) Cement, industrial by-product gypsum, anti-caking agent and mineral admixture are used as raw materials, and the formula is suitable for preparing cementing materials of mould-bag concrete. The cementing material does not need to use coarse aggregate and fine aggregate.

(2) The cement content in the cementing material is reduced to below 30%, and the solid waste is added, so that the requirement on the performance in the subsequent application can be met.

(3) The preparation process of the mould bag concrete adopts local materials, uses the soil of a construction site, and can ensure that the 28-day unconfined compressive strength of the concrete is more than 10MPa and the expansion degree is not less than 500mm under the selection of a reasonable formula, thereby meeting the requirements of various performances of the mould bag concrete.

(4) For the problem that the raw materials with higher water content are easy to generate agglomeration to influence the performance, the novel anti-agglomeration agent is innovatively added, so that the anti-agglomeration problem is well solved.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to fall within the scope of the invention.

Example 1:

And (5) a cementing material formula selection experiment.

Anti-caking agent: only inert components, and no functional components; is prepared by uniformly mixing 70% of micro silicon powder (800 meshes) and 30% of light calcium carbonate (1000 meshes).

And (3) molding, curing, testing the compressive strength of 7d and 28d and screening the cementing material proportion according to a cement mortar strength test method (I SO method) GB/T17671-2021.

Table 1 compressive strength test of different cement formulations

Example 2:

And (3) selecting an experiment of the mixing amount of the curing agent. The test method refers to the "JGJ/T70-2009 building mortar basic performance test method" for testing fluidity, curing time and compressive strength. Anti-caking agent: uniformly mixing 70% of micro silicon powder (800 meshes) and 30% of light calcium carbonate (1000 meshes) to obtain the anti-caking agent.

The cementing material comprises the following components:

Table 2 compressive strength test of different cement loadings

From the test results, the inert component (without adding calcium oxide) is used alone, the cement has good effect when the mixing amount of the cementing material is 30%, the mixing amount is improved, and the effect is further improved.

Example 3:

And (5) optimizing the mould bag concrete formula. The test method refers to the "JGJ/T70-2009 building mortar basic performance test method" for testing fluidity, curing time and compressive strength. The water content of the river bank soil is 19%. From the test results, the amount of water should not be too much, otherwise the 28d compressive strength is affected. The amount of water is preferably 650kg to 800 kg.

Table 3 compression strength test of mould bag concrete formulation

It is noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises an element.

The above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. The high-strength cementing material for the mould bag concrete is characterized by comprising the following raw materials in percentage by weight: 15-30% of cement, 20-35% of industrial byproduct gypsum, 10-20% of anti-caking agent and 35-45% of mineral additive; wherein the anti-caking agent comprises only a dispersing component and no functional component; the dispersing component is an inert component and does not react with water; the functional component is a water reactive component;

the anti-caking agent does not contain free calcium oxide and free magnesium oxide; the dispersion component is a substance insoluble or poorly soluble in water, wherein the insoluble or poorly soluble in water means that the solubility in water is less than 0.01g/100g at 20 ℃;

The dispersion component is one or more of a light porous material and a mesoporous material, the light porous material is diatomite, and the mesoporous material is mesoporous carbon or mesoporous silicon; or the dispersion component is one or more of quartz powder, kaolin, heavy calcium carbonate, light calcium carbonate and silica fume;

The cementing material is divided into a material A and a material B, wherein the material A comprises cement and mineral admixture; the material B contains industrial by-product gypsum and anti-caking agent.

2. The cement of claim 1, wherein the mass ratio of the a-material to the B-material is 3:1 to 1:2.

3. The cement of claim 2, wherein the mass ratio of the a-material to the B-material is from 2:1 to 1.2:1.

4. The cement of claim 1, wherein the cement meets one or more of the following conditions:

(1) The mineral additive is one or more selected from copper slag powder, phosphorus slag powder, fly ash, steel slag, natural zeolite and silica fume;

(2) The industrial byproduct gypsum is selected from one or more of desulfurized gypsum, phosphogypsum, titanium gypsum, fluorine gypsum, citric acid gypsum and salt gypsum.

5. The cement of claim 1, wherein the dispersing component is selected from the group consisting of a mixture of microsilica and light calcium carbonate.

6. The cementing material according to claim 1, wherein the dispersing component is quartz powder with fineness of more than 400 meshes;

or the dispersion component is micro silicon powder with fineness of more than 500 meshes;

Or the dispersion component is kaolin with fineness of more than 800 meshes;

or the dispersed component is heavy calcium carbonate with fineness of more than 300 meshes;

or the dispersion component is light calcium carbonate with fineness of more than 200 meshes;

or the dispersed component is diatomite with fineness of more than 500 meshes;

or the dispersion components are 50-70% of micro silicon powder and 50-30% of light calcium carbonate, wherein the fineness of the micro silicon powder and the light calcium carbonate is above 500 meshes.

7. The cementing material according to claim 6, wherein the dispersing component is quartz powder with fineness of more than 600 meshes;

or the dispersion component is micro silicon powder with the fineness of more than 800 meshes;

Or, the dispersion component is kaolin with fineness of more than 1000 meshes;

or the dispersed component is heavy calcium carbonate with fineness of more than 400 meshes;

or the dispersion component is light calcium carbonate with fineness of more than 300 meshes;

or the dispersed component is diatomite with fineness of more than 800 meshes.

8. A method of making a cement according to any one of claims 1 to 7, comprising the steps of: (1) mixing cement and mineral admixture to obtain a material A; (2) Premixing industrial byproduct gypsum and an anti-caking agent to obtain a material B; (3) mixing the material A and the material B.

9. Use of the cement of any one of claims 1-7 for form-bag concrete.

10. A mould-bag concrete, characterized in that it comprises the cement according to any one of claims 1-7, soil, water.

11. The modular bag concrete of claim 10, wherein the soil is a job site soil.

12. The modular bag concrete of claim 11, wherein the job site soil is one or more of coastal soil, lake coastal soil, river coastal soil, and river coastal soil.

13. The modular bag concrete of claim 10, wherein the soil moisture content is 10% -40%.

14. The modular bag concrete of claim 13, wherein the soil moisture content is 15% -30%.

15. The modular bag concrete of claim 13, wherein the soil moisture content is 20% -25%.

16. The modular bag concrete of claim 10, wherein the binder is present in an amount of 35% to 50% of the soil.

17. The mould bag concrete according to claim 10, wherein the soil, the cementing material and the water are added in the following weight ratio: cementing material: water=1400-1800:400-800:650-800.

18. The modular bag concrete of claim 10, wherein the concrete meets one or more of the following conditions:

(1) The mobility of the glue sand is 130-160mm;

(2) The slump expansion degree is not less than 500mm;

(3) Curing time is 15-30h;

(4) The unconfined compressive strength is above 6.5MPa in 7 days;

(5) The unconfined compressive strength is more than 10MPa in 28 days.

19. A method of preparing a mould-bag concrete according to any one of claims 10 to 18, characterized in that: the raw materials comprising cementing material, soil and water are stirred and mixed, and are injected into a mould bag.

20. The method for preparing the mould-bag concrete according to claim 19, wherein: a three-point pumping method is adopted.

21. The method for preparing the mould-bag concrete according to claim 19, wherein: the mould bag is 10-20 m long, 5-15 m wide and 10-30 cm thick.

22. Use of a mould-bag concrete according to any one of claims 10 to 18, characterized in that: the method is used for slope protection, bank protection, dyke fixing, sea filling, cofferdam and field making engineering.