CN113816623A

CN113816623A - Cementitious material, composite filler material, concrete and filler

Info

Publication number: CN113816623A
Application number: CN202111164292.9A
Authority: CN
Inventors: 欧阳仕元; 黄沛生; 杜向红; 崔国伟; 方振鹏; 梁德义; 邓波; 郑国雄; 钟杰; 车维维; 冯雪兰
Original assignee: Fankou Lead Zinc Mine of Shenzhen Zhongjin Lingnan Nonfemet Co Ltd
Current assignee: Fankou Lead Zinc Mine of Shenzhen Zhongjin Lingnan Nonfemet Co Ltd
Priority date: 2021-09-30
Filing date: 2021-09-30
Publication date: 2021-12-21

Abstract

The application relates to the technical field of concrete, and provides a cementing material, a composite filler material, concrete and a filler, wherein the total weight of the cementing material is 100%, and the cementing material comprises the following oxides in percentage by weight:

the oxide in the cementing material provided by the first aspect of the application can enable the composite filling body material slurry to be coagulated, and on the other hand, compared with ordinary cement, the strength of the filling body can be increased.

Description

Cementitious material, composite filler material, concrete and filler

Technical Field

The application belongs to the technical field of concrete, and particularly relates to a cementing material, a composite filling body material, concrete and a filling body.

Background

The first thing that one might think of is cement, which is used to prepare the packing, the cementitious material used to consolidate the tailings. Since 1824 the English man J.Aspdin first obtained cement production patent, cement has always been the most used and cheap cementing material for modern construction. The silicate cement is subjected to complex physical reaction and chemical reaction after meeting water to form cement paste with cohesiveness, then the strength is gradually improved, and hard cement stones are developed, so that the silicate cement can be used for preparing mortar and concrete meeting various performances, such as waterproof concrete, shrinkage-compensating concrete, heat-resistant concrete, acid-resistant concrete and radiation-proof concrete, and is a raw material for preparing various mortars and grouting materials. Over the past several decades, cement has been used in large quantities to prepare mine fill. Generally, the filler slurry contains 70% to 85% of solid components, wherein the content of the cementing material and the cement accounts for about 2% to 7% of the whole content, and if the requirement of the mine filling on the early strength is higher, the content of the cement is increased to more than 10%. The past practical construction experience proves that the tailing filling body prepared by cement as a cementing material can relatively quickly support the surrounding rock structure and improve the overall stability of the cavity. However, cement-made fillers also have their deficiencies.

The granularity of the tailings is less than 20 μm, and cement as a cementing material has two problems: firstly, the consolidation performance of materials with fine grain grade such as tailings and sandy soil and high mud content is poor, and the filling body achieves the design strength and consumes a large amount; secondly, the cement slurry is easy to separate and bleed, and the cement loss is serious. Therefore, the cement is used as a cementing material, and the fine fraction tailings have high mud mass fraction, fine granularity and high water content, so that the fine fraction tailings are difficult to efficiently dispose and recycle.

Disclosure of Invention

The application aims to provide a cementing material, a composite filler material, concrete and a filler, and aims to solve the problem of poor consolidation performance of the existing cement in the prior art.

In order to achieve the purpose of the application, the technical scheme adopted by the application is as follows:

in a first aspect, the present application provides a cementitious material comprising, in weight percent, oxides, based on the total weight of the cementitious material taken as 100%:

Na₂O 2.71～2.90wt％

MgO 4.43～4.62wt％

Al₂O₃ 7.52～7.71wt％

SiO₂ 20.00～22.94wt％

SO₃ 6.00～6.53wt％

CaO 52.12～57.48wt％

Fe₂O₃ 2.45～2.56wt％

ZnO 0.01～0.02wt％。

In a second aspect, the application provides a composite filler material, which comprises the above cementing material and filler material mixture, wherein the weight ratio of the filler material to the cementing material is 4-14: 48-63.

The composite filling material provided by the second aspect of the application is prepared by mixing a filling material and a cementing material in a weight ratio of 4-14: 48-63, the fluidity of the concrete and the strength of the filling body are improved, and the cohesiveness and the toughness of the filling materials are improved.

In a third aspect, the present application provides a concrete, which comprises the above composite filler material and water, and is obtained through mixing treatment.

The concrete provided by the application has good concrete fluidity, can be transported in pipelines, can be used as a pouring material, and can also be used as a filling body for filling mines.

In a fourth aspect, the present application provides a filling body obtained by solidifying the concrete.

The application provides a obturator can be used to the stope field of filling satisfying under the filling strength condition.

Drawings

FIG. 1 is a line graph of fine fraction tailings and cementing materials with different compounding ratios under 60% of filling materials in the embodiment of the present invention;

FIG. 2 is a line graph of fine fraction tailings and gelled materials with different compounding ratios under 62% of filling materials in the embodiment of the present invention;

FIG. 3 is a line graph of different compounding ratios of fine fraction tailings and cementing materials under 70% of filling materials in the embodiment of the present invention;

FIG. 4 is a line graph of the R7 strength average for different concentrations of filler material, different fine fraction tailings and cement compound ratios in an example of the invention;

FIG. 5 is a line graph of the R28 strength average for different concentrations of packing material, different fine fraction tailings and cement compound ratios in an example of the invention;

FIG. 6 is a line graph showing strength comparison of gelled materials and cements with different compounding ratios under 63% of filling materials in the example of the present invention;

FIG. 7 is a graph showing comparative curves of strength of gelled materials and cements with different compounding ratios under 64% of filler materials in an example of the present invention;

FIG. 8 is a graph showing comparative curves of strength of cementitious materials and cements with different compounding ratios under 67% filler material in an example of the present invention;

FIG. 9 is a graph showing strength comparison curves of cementitious materials and cements at different compounding ratios with 68% filler material in an example of the present invention;

FIG. 10 is a graph showing strength comparison curves of cement and gelled material of different compounding ratios with 69% filler in an example of the present invention;

FIG. 11 is a graph showing the relationship between the concentration, the sand-lime ratio and the diffusivity of an embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present application more clearly apparent, the present application is further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

In this application, the term "and/or" describes an association relationship of associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a is present alone, A and B are present simultaneously, and B is present alone. Wherein A and B can be singular or plural. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

In the present application, "at least one" means one or more, "a plurality" means two or more. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of the singular or plural items. For example, "at least one (a), b, or c", or "at least one (a), b, and c", may each represent: a, b, c, a-b (i.e., a and b), a-c, b-c, or a-b-c, wherein a, b, and c may be single or plural, respectively.

It should be understood that, in various embodiments of the present application, the sequence numbers of the above-mentioned processes do not mean the execution sequence, some or all of the steps may be executed in parallel or executed sequentially, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

The terminology used in the embodiments of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in the examples of this application and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The weight of the related components mentioned in the description of the embodiments of the present application may not only refer to the specific content of each component, but also represent the proportional relationship of the weight among the components, and therefore, the content of the related components is scaled up or down within the scope disclosed in the description of the embodiments of the present application as long as it is scaled up or down according to the description of the embodiments of the present application. Specifically, the mass described in the specification of the embodiments of the present application may be a mass unit known in the chemical industry field such as μ g, mg, g, kg, etc.

The terms "first" and "second" are used for descriptive purposes only and are used for distinguishing purposes such as substances from one another, and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. For example, a first XX may also be referred to as a second XX, and similarly, a second XX may also be referred to as a first XX, without departing from the scope of embodiments of the present application. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

According to a first aspect of the embodiments of the present application, there is provided a cement material, where the cement material includes the following oxides in percentage by weight, based on the total weight of the cement material as 100%:

Na₂O 2.71～2.90wt％

MgO 4.43～4.62wt％

Al₂O₃ 7.52～7.71wt％

SiO₂ 20.00～22.94wt％

SO₃ 6.00～6.53wt％

CaO 52.12～57.48wt％

Fe₂O₃ 2.45～2.56wt％

ZnO 0.01～0.02wt％。

the oxide in the cementing material can enable the composite filling body material slurry to be coagulated, and compared with ordinary cement serving as the cementing material, the filling body can be strengthened.

In a particular embodiment, the cement may comprise the following oxides in weight percentage, based on the total weight of the cement taken as 100%,

Na₂O 2.80wt％

MgO 4.58wt％

Al₂O₃ 7.62wt％

SiO₂ 21.94wt％

SO₃ 6.33wt％

CaO 54.16wt％

Fe₂O₃ 2.56wt％

ZnO 0.01wt％

the strength of the filling body can be further improved.

In some embodiments, the gel material is formed by mixing a plurality of solid dry (micro) powders, and the true density of more than 95 wt% of the gel material is 2.8-3.05 g/cm³Within the range of fineness of 250-350 meshes and the true density of the cementing material less than 95 wt% of 2.1-2.7 g/cm³Within the range, the fineness is within the range of 80-100 meshes, so that the cementing material is ensured not to have obvious powder segregation in the process of pipeline pneumatic transmission.

According to the second aspect of the embodiment of the application, the composite filling material comprises a mixture of a filling material and a cementing material, the weight ratio of the filling material to the cementing material is 4-14: 48-63, the fluidity of concrete and the strength of a filling body are improved, and the cohesiveness and the toughness of the filling material are improved.

In some embodiments, the filler material comprises tailings, and the tailings have a particle size of less than 20 μm. According to the filler composite material, the tailings obtained in the mining process are used as the raw materials, the cementing materials are added in a synergistic mode for compounding, the strength of the composite filler material meets the filling requirement by adding the cementing materials, and the flowability of the filler composite material with the tailings as the filling aggregate is improved, so that the use of the tailings as the filling aggregate is promoted, and a path is provided for efficient disposal and recycling of the tailings.

Furthermore, the tailings comprise fine-fraction tailings, the weight ratio of the fine-fraction tailings to the cementing material is 1: 4-1: 9, and the fine-fraction tailings are difficult to efficiently dispose and recycle due to high mud content, fine granularity and high water content.

The third aspect of the embodiment of the present application provides a concrete, including the concrete obtained by mixing the composite filler material and water in the embodiment of the present application, and the concrete provided in the embodiment of the present application has good fluidity, can be transported in a pipeline, and can be used as a casting material and a filler for filling a mine.

In some embodiments, on the basis of the technical scheme, in order to further improve the fluidity of the concrete in pipeline transportation, researchers make the composite filler material into the concrete and measure the diffusivity of the concrete, and research results show that the diffusivity of the concrete in the embodiments of the present application is in the range of 110-286 mm, so that the natural fluidity of the concrete can be improved, and the concrete does not need to be transported by adopting a pump mode. Illustratively, the determination of the degree of diffusion is primarily to understand the fluidity of the filled concrete and is aided by visual experience in assessing cohesiveness and water retention. The diffusivity is a concept of borrowing from concrete, and the diffusivity test cannot be unified and standardized from various aspects such as test equipment, test methods, measurement and reading data and the like at home and abroad at present. The test adopts the current universal 'diffusion cylinder method', the test equipment and the method are simple, and the test data can reflect the flowing characteristic of the concrete to a certain extent.

In some embodiments, in order to further improve the fluidity of the tailings and the cementing material as concrete, the composite filler material and water are mixed according to the weight ratio of 6: 4-7: 3 for mixing treatment.

Further, good fluidity of the concrete with the tailings and cementitious material as the filler composite was obtained when the composite filler material to water weight ratios were 67:33, 68:32, 69: 31.

A fourth aspect of embodiments of the present application provides a packing body. The filling body in the embodiment of the present application includes the filling body obtained by performing the solidification treatment on the concrete in the embodiment of the present application, and the filling body can be widely applied to the technical field of buildings or concrete, wherein the concrete in the embodiment of the present application can be solidified to form the filling body after the pouring treatment.

In some embodiments, in order to further improve the strength of the filling body, researchers research the strength of the filling body, and the research shows that the strength of the filling body in 3 days is within the range of 0.37-1.37 MPa, and the strength of the filling body in 28 days is within the range of 2.2-5.6 MPa, so that the requirements of the filling industry on the strength of the filling body are met.

The following description will be given with reference to specific examples.

Example 1

The equipment and tools used for the test include: industrial barrel, stirrer, single-shaft press, electronic scale, standard curing box, 70.7 × 70.7 × 70.7mm triple mortar test mould and matched mould sleeve, drying box, fluidity test mould, 500 × 500mm glass plate, round mould for setting time, 100 × 100mm glass sheet, cement setting time determinator, water bucket, medicine spoon, glass rod, rubber head dropper, iron disc, shovel, steel ruler, tamping rod, rag, etc.

S0 preparation of composite filling material

S010, measuring the moisture content of the aggregate:

weighing the mass of a dried iron disc in advance, taking out a proper amount of fine-fraction tailings samples by using the iron disc, weighing the wet volume weight of the fine-fraction tailings samples, putting the fine-fraction tailings samples into a drying box for drying, taking out the iron disc together with the dried fine-fraction tailings samples after 24 hours, weighing the volume weight of the iron disc again, and calculating the water content C; and calculating the mass of the weighed water and the mass of the tailings according to the water content C.

S020 and weighing materials

Separately weighing 120g + C of fine-fraction tailings, 480g of gelled material and 400g-C of water by using an electronic scale, wherein the weighing precision is as follows: the cementing material and water are plus or minus 0.5 percent; the fine fraction tailings is +/-1%;

s030 preparation of concrete

Firstly, pouring 400g-C of weighed water into a stirring barrel, adding 480g of a cementing material, and slowly stirring for 1 min. Then adding 120g + C of fine-grade tailing and tailing, and continuing to stir slowly for 2 min. And scraping and scattering the solid materials at the bottom of the stirring barrel compacted by the action of the stirrer. And quickly stirring for 1min to finish the preparation of the concrete.

S1, forming the concrete by the concrete forming treatment

S110, preparing a die

Before molding, roughly calculating the number of the molds needed by the experiment, classifying according to the proportion and placing on a smooth and flat floor or board, coating a thin layer of mineral oil on the inner surface of the test mold, and placing a mold sleeve on the mold;

s120, casting mold

The mixed concrete is firstly stirred for three times, and then the concrete is slowly poured into a test mould. The mixed concrete is loaded into the mould in two layers, the loading thickness of each layer is approximately equal and is about half of the mould. The filled concrete is slightly higher than the top surface of the mould so as to avoid irregular test pieces caused by shrinkage after the filled concrete is cured. Wherein, the concrete added each time needs to be uniformly inserted and beaten by a tamping rod from the edge to the center in the spiral direction. When bottom concrete is inserted and tamped, the tamping bar reaches the bottom of the test mold; when the upper layer is inserted and pounded, the pounding rod should penetrate through the upper layer and then be inserted into the lower layer for 20-30 mm. And then inserting and pulling the test mold along the inner wall of the test mold for a plurality of times by using a spatula. After the tamping is carried out, the periphery of the test mold is lightly knocked by a rubber hammer until a cavity left by the tamping rod disappears.

S2, solidifying the concrete casting to obtain a test piece

S210, after the concrete does not bleed, removing the die sleeve, scraping the surface of the test piece, jolting and exhausting, after the test piece is finally set, removing the die by using a spray gun, counting the test piece, numbering the test piece, and counting the composition of the test piece.

And S220, immediately covering the surface of the test piece with a water-impermeable film after the test piece is formed.

S3, maintaining the test piece

S310, performing wet treatment and dry treatment on the concrete casting in a circulating manner, wherein the dry and wet circulating curing time is 28 d; keeping the surface of the test piece moist and keeping the moisture for 24h at the constant temperature of 20 ℃ and the humidity of 90 percent, so as to prevent the test piece from cracking; the test pieces were dried at a temperature of 50 ℃ for 12h to ensure that the test pieces could be shaped.

Example 2 to example 60

Concrete and test pieces were prepared as in example 1 by varying the concentration of the filler material and the ratio of fine fraction tailings to cementitious material. The concentrations of the filler materials and the ratios of the fine fraction tailings and the cement in examples 2 to 60 are shown in table 1, and the sand-lime ratio in the table indicates the ratio of the fine fraction tailings and the cement to explain the above.

Comparative examples 1 to 60

Slurries and test pieces were prepared as in example 1 by varying the concentration of the filler material and the ratio of fine fraction tailings to cement. The concentrations of the fillers and the ratios of the fine tailings and the cement in comparative examples 1 to 60 are shown in table 2, and the sand-ash ratio in the table is the ratio of the fine tailings and the cement to explain.

The test pieces were subjected to strength property test

The strength tests of 7d and 30d were performed on the test pieces formed by solidification in examples 1 to 60 and comparative examples 1 to 60, wherein the test apparatus: uniaxial press, test mode as follows:

and taking out the test piece from the maintenance place, counting the number of the test pieces, performing a test in time, and wiping the surface of the test piece and the upper and lower bearing plates. The test piece is placed on a cushion block of the testing machine, and the bearing surface of the test piece is perpendicular to the top surface during molding. The center of time is aligned with the center of the lower cushion block of the testing machine, and the testing machine is started. And continuously and uniformly loading in the test process until the test piece is damaged, then recording the damage load, cleaning the tester after the test is finished, and obtaining the test result, which is shown in tables 1 to 2.

Table 1 content of each component of examples 1 to 60 and statistical results of strength test

Table 2 content of each component and statistical results of strength test in comparative examples 1 to 60

As can be seen from tables 1 to 2 and from fig. 1 to 3, among others: firstly, a fine-grain tailing filling indoor test shows that the strength of concrete with the same concentration is increased along with the increase of the ratio of ash to sand;

as can be seen from tables 1 to 2 and from fig. 4 to 5 in combination: secondly, the strength of the concrete with the same sand-lime ratio is increased along with the increase of the concentration;

as can be seen from tables 1 to 2 and from fig. 6 to 10 in combination: and thirdly, compared with the P.O42.5R cement, the concrete prepared by adopting the cementing material has greatly increased strength no matter the strength is 7 days or 28 days.

Testing the flow property of concrete

The concrete provided in example 3, example 6, example 21, example 24, example 33, example 39, example 51 and example 59 and the concrete provided in comparative example 3, comparative example 6, comparative example 21, comparative example 24, comparative example 33, comparative example 39, comparative example 51 and comparative example 59 were subjected to the diffusibility measurement.

The testing method of the diffusivity comprises the following steps: a small diffusion cylinder is adopted to be arranged on a glass plate marked with scales, the surface of the glass plate is smooth and flat, the diffusion cylinder is a cylindrical barrel, the inner diameter of an upper opening and a lower opening is 8cm, and the height is 8 cm. The test steps are as follows: firstly, wiping the inner wall and the edge of a diffusion cylinder clean by using a rag, placing the diffusion cylinder on a horizontal and clean glass plate, pouring proportioned concrete from the upper opening of the diffusion cylinder, scraping the upper opening by using a steel ruler, quickly and vertically lifting the diffusion cylinder, diffusing the concrete on the glass plate into a circle, and measuring the diameters of the two circles in the vertical direction to obtain the average value of the diffusivity of the concrete. The results of the experiments are shown in tables 3 to 4.

Table 3 statistical results of the content and diffusivity tests of each component in example 3, example 6, example 21, example 24, example 33, example 39, example 51 and example 59

TABLE 4 statistical results of the content and diffusivity tests of each component in comparative examples 3, 6, 21, 24, 33, 39, 51 and 59

Reference example number	Concentration (wt%)	Ratio of ash to sand	Cement diffusivity (mm)
				Comparative example 3	60	1:6	200
Comparative example 6	60	1:9	170
				Comparative example 21	63	1:6	110
Comparative example 24	63	1:9	95
				Comparative example 33	66	1:6	95
Comparative example 39	66	1:9	90
				Comparative example 51	69	1:6	90
Comparative example 54	69	1:9	90

Among them, as can be seen from tables 3 to 4 and fig. 11: the fluidity of the cement, whether the cement is a cementing material or P.O42.5R cement, is reduced along with the increase of the concentration, and meanwhile, the fluidity of the cement is gradually reduced along with the reduction of the sand-lime ratio; ② the cementing material has obvious fluidity advantage relative to P.O42.5R cement with the same concentration and proportion; thirdly, after the concentrations of the cementing material and the cement reach 67 percent and 63 percent respectively, the cementing material and the cement basically lose fluidity and are in a solid state in the test process.

The present invention is not intended to be limited to the particular embodiments shown and described, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed.

Claims

1. The cementing material is characterized by comprising the following oxides in percentage by weight, based on the total weight of the cementing material as 100 percent:

2. the cementitious material of claim 1, wherein the cementitious material has a true density of 2.8 to 3.05g/cm³The specific surface area is 370-390 m²Per kg, fineness of 250-350 meshes, and bulk density of 1.468-1.470 g/cm³。

3. The cement of claim 1, wherein the cement comprises oxides in the following weight percentages, based on the total weight of the cement taken as 100%,

4. a composite filler material, which comprises a mixture of the cementitious material and the filler material according to any one of claims 1 to 3, wherein the weight ratio of the filler material to the cementitious material is 4 to 14:48 to 63.

5. The composite filler material of claim 4, wherein the filler material comprises tailings, and wherein the tailings have a particle size of less than 20 μm.

6. A concrete comprising the composite filler material according to claim 4 or 5 and water, wherein the concrete is obtained by mixing treatment.

7. The concrete of claim 6, wherein the diffusivity of the concrete is in the range of 110 mm to 286 mm.

8. The concrete according to claim 7, wherein the composite filler material and water are mixed according to a weight ratio of 6:4 to 7: 3.

9. A filler obtained by subjecting a concrete comprising the concrete according to any one of claims 6 to 8 to a setting treatment.

10. The filling body according to claim 9, wherein the filling body has a 7-day strength of 0.3 to 6.0MPa and a 28-day strength of 0.4 to 8.7 MPa.