CN111324950B - Design method of low-cost composite excitation filling cementing material - Google Patents

Abstract

The invention discloses a design method of low-cost composite excitation filling cementitious material, which belongs to the technical field of filling mining. This method adopts high-temperature curing, conducts the orthogonal test of the strength of the cemented filling body, and quickly obtains the optimal formula of the salt-based activator and the base activator; then conducts the orthogonal design of the compound activator ratio and the strength test of the cemented filling body; By establishing and solving the optimal design model of the composite activator ratio, the optimal formula of the composite activator can be obtained, thereby preparing the low-cost composite activator filled cementitious material. This design method can quickly obtain the optimized formulation of low-cost backfill cementitious material activator according to the physicochemical properties of different solid wastes, thereby preparing low-cost backfill cementitious materials suitable for different tailings aggregates and strength requirements. The large-scale and high-value-added resource utilization of solid waste in backfill mining lays the foundation.

Description

A low-cost design method for composite excitation-filled cementitious materials

technical field

The invention belongs to the technical field of backfill mining, in particular to a design method of a low-cost composite excitation backfill cementitious material.

Background technique

With the rapid development of my country's national economy and the continuous development of resources, high-grade and good-condition resources are becoming increasingly depleted, and more refractory ore bodies such as deep burial, high ground pressure and rich water are faced. For safety, environmental protection and green mining, the filling mining method is the first choice. The backfill mining method has complex mining process, low production capacity and high mining cost. Therefore, the development and utilization of low-cost and high-performance backfill cementitious materials is the only way to improve the economic and environmental benefits of backfill mining.

Over the past 10 years, people have been exploring the use of various industrial solid wastes such as slag, steel slag, and desulfurized gypsum to prepare low-cost, high-strength new filling cementitious materials. The research results show that the smelting industrial waste slag after high temperature calcination and water quenching has potential different degrees of water hardening activity. Its activity is closely related to the type of metallurgical slag, the mineral composition and the treatment process of the discharge process. Therefore, different types of solid waste and different treatment processes of the same solid waste have great differences and uncertainties in the potential activity of the waste residue, which brings technical difficulties to the resource utilization of industrial solid waste. According to the current development of filling cementitious materials using industrial solid waste, they are mainly prepared by mechanical grinding (force excitation) and chemical excitation agents. It can be seen that the grinding fineness of solid waste materials, as well as the activator and formulation, not only affect the performance of the cementitious material (strength of the filling body and the fluidity of the slurry), but also determine the cost of the filling cementitious material. Obviously, the finer the solid waste grinding, the higher the activity, but the grinding cost increases with the increase of the grinding fineness. Chemical stimulators mainly include sulfate-based salt-based stimulators, calcium oxide-based base stimulators, and composite stimulators prepared from alkali salts. Undoubtedly, the activator material and formulation not only affect the performance of the filling cementitious material, but also affect the cost of the filling cementitious material, and are the key technology for preparing low-cost filling cementitious materials based on multi-solid waste.

Chinese invention patents CN103613294A, CN104609749A, CN103787601A disclose the compound excitation material formula and preparation method for the development of filling cementitious materials with slag as the main material; CN102249611A, CN102633448A, CN103043975A, CN103102089A, CN106565187B and CN1075A have invented 882 The formula and preparation method of filling cementitious material; for rod frosting and mixed aggregate, CN103803826A, CN103803928A and CN103803929 A disclose the formula of consolidation powder filling cementitious material; CN107540302A invented the use of low-quality steel slag, slag, loess and phosphogypsum etc. Proportion of filling cementitious material prepared from solid waste; CN102234191A, CN108178597A and CN110054423A invented the formula of early-strength filling cementitious material suitable for downward layered filling mining; CN102924005 A and CN108439910 A disclosed filling glue with micro-expansion The formula of cementitious material; CN108240233A invented the proportion of filling cementitious material prepared by using cement synergist; for mixing coarse aggregate with coal gangue and filling coal mining technology, CN105152601A, CN105753418A, CN107619249A, CN107805023A and CN108083701A invented the proportion of filling cementitious material and preparation method; CN110218010A also discloses a method for preparing filling cementitious material by calcining steel slag, slag, ash and other mixtures.

From the above, it can be seen that the above invention is characterized in that the formulation and preparation method of the filling cementitious material are disclosed for specific solid waste. The disclosed activator materials and ratios are limited to specific purposes and specific conditions, and are not suitable for the development of multi-solid waste backfilling cementitious materials, and it is also difficult to obtain optimal formulations of composite activators for different backfill mine tailings.

Different from building cementitious materials, the development of filling cementitious materials based on metallurgical slag involves a variety of solid waste resources with complex and uncertain factors. The activator and formulation of filling cementitious materials can only be obtained through optimized design. Filled cementitious material with high performance and low cost.

SUMMARY OF THE INVENTION

Aiming at the development status and existing problems of filling cementitious materials, the present invention provides a design method of low-cost composite excitation filling cementitious materials.

In order to solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a low-cost design method of composite excitation filling cementitious material, the steps of which include:

(1) Formulation design of salt-based activator: using sulfate activator as the main agent and base activator as auxiliary, prepare salt-based activator cementitious material, and add filling aggregate to prepare cemented filling body, which is carried out under high temperature curing conditions Orthogonal test of 3d and 7d strength of cemented filling body, using range analysis to design the formula of salt-based activator, so as to obtain the optimal formula of salt-based activator.

(2) Base activator formulation design: base activator is the main agent, sulfate activator is supplemented, base activator gelling material is prepared, and filling aggregate is added to prepare cemented filling body, which is carried out under high temperature curing conditions Orthogonal test of 3d and 7d strength of cemented filling body, using range analysis to design the formula of base activator, so as to obtain the optimal formula of base activator.

(3) Establish a relationship model between the strength of the cemented filling body, the cost of the filling cementitious material and the composite activator: According to steps (1) and (2), the optimized formula of the salt-based activator and the optimized formula of the base activator are obtained to determine the composite activator formula. The 7d and 28d strength orthogonal tests of the cemented backfill were carried out under standard curing conditions, and the test results of the strength of the cemented backfill were obtained. The quadratic polynomial was used to carry out a stepwise regression analysis on the test results, and the strength of the cemented backfill and the compound activator were established. The relational model of the ratio:

R _7d = F ₁ ( X ), R _28d = F ₂ ( X )

In the formula, R _7d represents the 7d strength of the cemented filling body, F ₁ ( X ) represents the 7d strength model of the cemented filling body; R _28d represents the 28d strength of the cemented filling body; F ₂ ( X ) represents the 28d strength model of the cemented filling body;

According to the raw material cost of filling cementitious material and the ratio of filling cementitious material, the cost model of filling cementitious material is established: C _T = F ₃ ( X );

In the formula, CT represents the cost of filling and cementing materials; _{F 3} ( X ) represents the cost model of filling and cementing materials;

X = { x ₁ , x ₂ ,…, x _n } ^T represents the filled cementitious material composite activator variable.

(4) Taking the cost of the composite excited filling cementitious material as the optimization goal, and taking the 7d and 28d strength of the cemented filling body as the constraint condition, the optimization model of the low-cost filling cementitious material ratio is established as follows:

Optimization objective: MinC _T = Min F ₃ ( X )

Constraints: R _7d = F ₁ ( X )≥[ R _7d ]; R _28d = F ₂ ( X )≥[ R _28d ]

In the formula, [ R _7d ] and [ R _28d ] are the design strength indexes of the backfill mining cemented backfill 7d and 28d, respectively;

By solving the above optimization model, the optimal formula of the composite exciter with the lowest cost of the backfill cementitious material can be obtained, so as to prepare the low-cost composite excitation backfill cementitious material that meets the mining requirements of the backfill method.

In the step (1), the formula of the salt-based activator gelling material is: sulfate activator 13-17 wt%, base activator 2-6 wt%, industrial thenardite 0-1.0 wt%, and the balance is slag micropowder .

In the step (2), the base activator gelling material formula is: base activator 8-12 wt%, sulfate activator 2-6 wt%, industrial thenardite 0-1.0 wt%, and the balance is slag Micropowder.

In the steps (1) and (2) of the present invention, the sulfate activator is desulfurized gypsum, the moisture content of the sulfate activator powder is <8wt%, the SO ₃ content is >38wt%, and the powder fineness is <15%.

In the steps (1) and (2), the base activator is cement clinker and quicklime, the moisture content of the base activator powder is less than 3wt%, the CaO content is more than 80wt%, and the powder fineness is less than 5%.

In the steps (1) and (2) of the present invention, the high temperature curing conditions are a temperature of 38-42°C and a humidity of ≥95%.

In the step (3) of the present invention, the ratio of the sulfate activator in the compound activator formula is determined according to the ratio of the sulfate activator in the optimized formula of the salt-based activator in step (1), which fluctuates by 1-2% to determine the test range. The base elicitor determines the test range according to the base elicitor optimization formula in step (2), the ratio of alkali salt elicitor fluctuates by 1-2%; that is, A=A ₁ ±(1-2%), B=B ₂ ±( 1-2%);

A is the ratio of sulfate activator in the compound activator formula, A ₁ is the ratio of sulfate activator in the optimized formula of salt-based activator in step (1); B is the ratio of base activator in the composite activator formula , B ₂ is the base activator ratio in the base activator optimization formula in step (2);

The present invention also includes the verification of the strength of the cemented filling body and the cost analysis of the formula of the composite excited filling cementitious material obtained in step (4).

In the step (3) of the present invention, the method for detecting the strength of the cemented backfill refers to the standard "GB/T 17671-1999 Test Method for Cement Mortar Strength (ISO Method)".

The beneficial effects of this technical solution are: in view of the complex and variability of the physical and chemical characteristics of the current solid waste, curing at high temperature is used to quickly obtain the optimized formula of the two activators of the base and the base, and thus the low-cost activator material Formula range design, design of cemented backfill strength test plan for optimal design of compound excited backfill cementitious material formulation. At present, the development of new cementitious materials usually adopts the trial and error method, that is, with the help of the experience of researchers, trial and error experiments of different activator material formulation schemes are carried out. Not only is it difficult to obtain a reasonable range of activator formulations due to the differences in the experience of designers; at the same time, the strength test of cemented fillings based on multiple trial-and-error methods not only requires a large amount of test work, but also is difficult to obtain the optimal formulation. The high-temperature curing test and the 3d and 7d strength test of the cemented backfill were used. The curing conditions can accelerate the hydration reaction rate of the cementitious material and shorten the strength test time of the cemented backfill of the cementitious material. When making decisions about the optimal formulation of low-cost cementitious materials, the strength of the cemented filling body needs to meet the strength requirements of the cemented filling body. Therefore, the 7d and 28d strength tests of the cemented filling body are carried out under standard curing conditions, and based on these constraints, the cemented filling body is established. The optimization model of the solidified material is used to optimize the design. To sum up, the design method disclosed in the present invention can quickly obtain an optimized formulation of a composite activator for solids with different physicochemical properties, laying a foundation for the application of solid waste in backfill mining, thereby obtaining significant benefits and environmental protection benefit.

Description of drawings

The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

Fig. 1 is the particle size distribution curve of embodiment 1 slag micropowder;

Fig. 2 is the particle size distribution curve of embodiment 1 desulfurization gypsum;

Fig. 3 is the particle size distribution curve of embodiment 1 cement clinker;

Fig. 4 is the particle size distribution curve of the whole tailings of an iron ore in Hebei in Example 1.

Detailed ways

The design method of this low-cost composite excitation filling cementitious material adopts high temperature curing to quickly obtain the optimal formula of salt-based activator and base activator; Strength test; on this basis, an optimization model of composite activator is established to optimize the ratio; finally, the strength verification test of the cemented filling body is carried out and the economic analysis of the filling cementitious material is carried out. Its implementation specifically includes the following steps:

1. Formula design of salt-based activator

(1) According to the available salt-based activator materials, determine that the salt activator is industrial by-product gypsum, preferably desulfurized gypsum; the moisture content of the sulfate activator powder is <8wt%, the SO ₃ content>38wt%, and the powder fineness <15%;

(2) The ratio of salt-based activator is: 13-17 wt% of salt-based activator, 2-6 wt% of alkali activator, 0-1.0 wt% of industrial thenardite, and the balance is slag powder.

(3) Use sulfate activator as the main agent and base activator as auxiliary to prepare salt-based activated filling cementitious material, and add filling aggregate to prepare cemented filling body, under the conditions of high temperature and humidity ≥95% at 38-42℃ Maintenance, carry out the 3d and 7d strength orthogonal tests of the cemented filling body of the salt-induced cementitious material, and obtain the strength test results of the cemented filling body;

(4) According to the strength test results of the cemented filling body, the formula of salt-based activator for the 3d and 7d strength of the cemented filling body was rapidly optimized by using the range analysis, so as to obtain the optimized formula of the salt-based activator.

2. Base activator formulation design

(1) According to the available base activator materials, the base activator is cement clinker, quicklime or other alkaline materials, preferably cement clinker; the base activator powder moisture content <3wt%, CaO content>80wt %, powder fineness <5%;

(2) The ratio of base activator is: base activator 8-12 wt%, sulfate activator 2-6 wt%, industrial thenardite 0-1.0 wt%, and the balance is slag powder;

(3) The base activator is used as the main agent, and the sulfate activator is supplemented to prepare the base-activated filling gelling material, and adding filling aggregate to prepare the cemented filling body. After curing, carry out the 3d and 7d strength orthogonal tests of the cemented filling body of alkali-excited cementitious materials, and obtain the strength test results of the cemented filling body;

(4) According to the strength test results of the cemented filling body, the base activator formula of the 3d and 7d strength of the cemented filling body was quickly optimized by using the range analysis, so as to obtain the optimized formula of the base activator.

3. Establish the strength of cemented backfill and the cost model of composite excited backfill cementitious material

(1) According to steps 1 and 2, obtain the optimized formula of the salt-based activator and the base activator, determine the formula range of the composite activator, and carry out the orthogonal experimental design of the strength of the cemented filling body at a temperature of 22±2℃ and a humidity of ≥95% Under the standard curing conditions, the 7d and 28d strength test of the cemented backfill was carried out, and the strength testing method was based on the standard "GB/T 17671-1999 Cement Mortar Strength Test Method (ISO Method)", and the result of the cemented backfill strength test was obtained; In the compound activator formula, the ratio of sulfate activator is A=A ₁ ±(1-2%), and the ratio of base activator is B=B ₂ ±(1-2%); A ₁ is the base of step 1 The ratio of sulfate activator in the activator optimization formula, and B ₂ is the base activator ratio in the base activator optimization formula in step 2;

(2) Stepwise regression analysis was carried out on the test results of the strength of the cemented backfill by using a quadratic polynomial, and a relationship model between the strength of the cemented backfill and the ratio of the composite activator was established:

R _7d = F ₁ ( X ), R _28d = F ₂ ( X )

In the formula, R _7d represents the 7d strength of the cemented filling body, F ₁ ( X ) represents the 7d strength relationship model of the cemented filling body; R _28d represents the 28d strength of the cemented filling body; F ₂ ( X ) represents the 28d strength relationship model of the cemented filling body;

(3) According to the raw material cost of filling cementitious material and the ratio of compound activator filling cementitious material, establish the cost model of filling cementitious material: C _T = F ₃ ( X )

In the formula, CT represents the cost of filling cementitious material; _{F 3} ( X ) represents the cost model of filling cementitious material.

4. Establishment of low-cost filling cementitious material composite activator optimization model

(1) Taking the cost of the composite excited filling cementitious material as the optimization goal, and taking the 7d and 28d strength of the cemented filling body as the constraint condition, establish a low-cost composite excited filling cementitious material ratio optimization model:

Optimization objective: MinC _T = Min F ₃ ( X )

Constraints: R _7d = F ₁ ( X )≥[ R _7d ]; R _28d = F ₂ ( X )≥[ R _28d ]

In the formula, [ R _7d ] and [ R _28d ] are the design strength indexes of the backfill mining cemented backfill 7d and 28d, respectively;

(2) By solving the above optimization model, the optimal formula of the composite activator that meets the strength requirements of the backfill mining cemented backfill and the lowest cost of the cementitious material can be obtained, thereby preparing the low-cost backfill cementitious material.

5. Formulation verification test and economic analysis of low-cost filling cementitious materials

(1) For the low-cost composite excitation filling cementitious material obtained in step 4, the strength verification test of the cemented filling body is carried out;

(2) According to the above verification test results, combined with the mining method, recovery process and technical parameters of the backfill mine, the cost analysis of the low-cost composite excitation backfill cementitious material is carried out.

Example 1

Aiming at the full tailings of an iron ore in Hebei, the design method of low-cost backfill cementitious material for the subsequent backfill mining of an iron ore in Hebei by composite excitation includes the following steps:

1. Formula design of salt-based activator

For an iron ore in Hebei filled with full tailings aggregates, desulfurized gypsum was selected as the main activator, cement clinker was used as the auxiliary activator, and industrial thenardite was added as an early strength agent to stimulate the potential activity of slag micropowder.

The fineness of the slag micropowder in this example is 4.27%, and its particle size distribution curve is shown in Figure 1 _; The particle size distribution curve is shown in Figure 2; the moisture content of the cement clinker powder is 2.7wt%, the CaO content is 86.8wt%, and the fineness is 4.5%, and the particle size distribution curve is shown in Figure 3; The content of 200-mesh fine particles in the tailings reaches 78%, and the particle size distribution curve is shown in Figure 4.

According to experience, the proportion of desulfurized gypsum as the main activator of the salt-based activator is 13-17wt%, the proportion of auxiliary activator to cement clinker is 2-6wt%, and 0-1wt% of industrial thenardite is added, and the cement-sand ratio is 1 : 4 (that is, the ratio of filling cementitious material to full tailings filling aggregate) and the filling slurry concentration is 64%, the formula of salt-based activator is orthogonally designed, and the rapid speed After curing, the 3d and 7d strength tests of the cemented filling body were carried out, and the 3d and 7d uniaxial compressive strength test results of the cemented filling body of the salt-based excited filling cementitious material were obtained. The test results are shown in Table 1.

Table 2 shows the range analysis results of the strength orthogonal test of the cemented backfill of the salt-based excited backfill cementitious material. It can be seen that the optimal formula of the salt-based activator for the 3d strength of the cemented backfill is 4wt% of cement clinker, 14wt% of desulfurized gypsum, and 0.5wt% of industrial thenardite; the optimal formula of the salt-based activator of 7d strength is 4wt% of cement clinker %, desulfurization gypsum 16wt%, industrial mirabilite 0.5wt%; the optimized formula of salt-based activator based on the strength of cemented backfill at two ages is combined, and the optimized formula of salt-based activator is determined to be 4wt% of cement clinker and 15wt% of desulfurized gypsum. , industrial thenardite 0.5wt%; the slag powder is 80.5wt%.

Table 1: Orthogonal test results of strength of cemented backfill of salt-based excited backfill cementitious material under high temperature curing conditions

Table 2: The results of the orthogonal test of the strength of the cemented backfill of the salt-based excited backfill cementitious material under the condition of high temperature curing

2. Base activator formulation design

For an iron ore in Hebei filled with full tailings aggregate, cement clinker was used as the main activator, desulfurized gypsum was used as an auxiliary activator, and industrial thenardite was added as an early strength agent to stimulate the potential activity of slag micropowder.

According to experience, the main activator cement clinker ratio range is 8-12wt%, the auxiliary activator desulfurization gypsum ratio range is 2-6wt%, and 0-1wt% industrial thenardite is added, and the mortar ratio is 1:4 and the material The slurry concentration is 64%, the base activator formula is orthogonally designed, the rapid curing is carried out under the conditions of high temperature and humidity ≥ 95% at 40°C, and the 3d and 7d strength tests of the cemented filling body are carried out to obtain the base-activated filling gelation. The 3d and 7d uniaxial compressive strength test results of the material cemented filling body are shown in Table 3.

Table 4 shows the range analysis results of the orthogonal test of the strength of the cemented filling body of the base excited filling of the cementitious material. It can be seen that the optimal formula of the base activator for the 3d strength of the cemented filling body is 12wt% of cement clinker, 4wt% of desulfurized gypsum, and 1wt% of industrial thenardite; the optimal formula of the base activator of 7d strength is 10wt% of cement clinker , desulfurization gypsum 4wt%, industrial thenardite 0wt%. Based on the optimized formula of base activator for the strength of cemented backfill at two ages, it is determined that the optimized formula of base activator is 10wt% of cement clinker, 4 wt% of desulfurized gypsum, and 0wt% of industrial mirabilite; the slag powder is 86wt% .

Table 3: Orthogonal test results of cement filling strength of base excited filling cementitious material under high temperature curing conditions

Table 4: The results of the orthogonal test of the strength of the base-excited filling cementitious material cemented filling body under high temperature curing conditions

3. Establish a model for the strength of cemented filling and the cost of filling cementitious materials

According to the optimized formulations of the base and base activators obtained in steps 1 and 2, and fluctuate up and down at intervals of 2%, the range of the composite activator of the alkali activator of cement clinker is 8~12wt%, and the design range of the salt activator of desulfurization gypsum is 13~17 wt% and industrial thenardite 0wt%. Using the cement-sand ratio of 1:8 and the slurry concentration of 66%, the 7d and 28d strength orthogonal tests of the cemented backfill were carried out under standard curing conditions. According to the test results in Table 5 and the raw material cost of the filling cementitious material, the strength of the cemented filling body and the cost model of the filling cementitious material are established as follows:

R _7d =-0.159-0.00338x ₂ x ₂ +0.0139x ₁ x ₂

R _28d =0.216+0.258x ₁ +0.0397x ₂ -0.0275x ₁ x ₁ -0.0119x ₂ x ₂ +0.0247x ₁ x ₂

C _T =580.58-85.83x ₁ -107.43x ₂ +1.31x ₂ x ₂ +9.79x ₁ x ₂

Among them, x ₁ represents the proportion of cement clinker in the composite excited filling cementitious material, wt%;

x ₂ represents the proportion of desulfurized gypsum in the composite excited filling cementitious material, wt %.

Table 5: Orthogonal test results of cement filling strength of composite excited filling cementitious material under standard curing conditions

4. Establish and solve the optimization model of low-cost filling cementitious material activator formulation

The design strengths of cemented backfills 7d and 28d in the subsequent backfill mining of an iron ore mine in Hebei are: [ R _7d ]=1.0MPa and [ R _28d ]=3.0MPa, respectively. Taking the cost of the composite excited filling cementitious material as the optimization goal, and taking the 7d and 28d strength of the cemented filling body as the constraint condition, the optimization model of the composite excitation agent ratio of the low cost filling cementitious material is established as follows:

Optimization objective: MinCT = Min ( _{580.58-85.83x 1} -107.43x ₂ +1.31x ₂ x ₂ +9.79x ₁ x ₂ )

Constraints: R _7d =-0.159-0.00338x ₂ x ₂ +0.0139x ₁ x ₂ ≥1.0MPa

R _28d =0.22+0.26x ₁ +0.040x ₂ -0.028x ₁ x ₁ -0.012x ₂ x ₂ +0.025x ₁ x ₂ ≥3.0MPa

By solving the above-mentioned optimization model of the composite activator for filling cementitious materials, the optimal formula of composite activating agent with the lowest cost of filling cementitious material with full tailings aggregate of an iron ore in Hebei is obtained: 10wt% of cement clinker and 15wt% of desulfurized gypsum; Therefore, it was determined that the full tailings filling cementitious material formula of an iron ore in Hebei is 10wt% of cement clinker, 15wt% of desulfurized gypsum, 75wt% of slag micropowder, and the ratio of composite activator to slag micropowder is 1:3.

, Low-cost filling cementitious material verification test and economic analysis

According to the optimized formulation of the activator obtained in step 4, a cementitious material filled with full tailings of an iron ore in Hebei was prepared. The cement-sand ratio was 1:4 and 1:8, and the slurry mass concentration was 66%. The verification test of filling cementitious material was carried out. It can be seen that when the cement-sand ratio is 1:4, the 28d strength of the full tailings cemented backfill of an iron ore in Hebei reaches 4.91MPa>[R _28d ] design strength, which meets the strength requirements of the subsequent mining cemented backfill; At 1:8, the strength of the cemented filling body 28d reaches 1.54MPa. The strength of the low-cost backfill cementitious material with a cement-sand ratio of 1:8 in this example is comparable to the strength of a 42.5 cement cementitious material with a cement-sand ratio of 1:4, and the cost of the cementitious material is only 42.5 cement. 1/2 the cost of the cementitious material. Obviously, the cost of the filling cementitious material in this embodiment is low and the strength of the cemented filling body is high.

Table 6: Strength verification test and material cost of cemented backfill with full-tailings composite excitation backfill of iron ore

Claims (9)

1. A design method of a low-cost composite excitation filling cementing material is characterized by comprising the following steps:

(1) preparing a base activator filling cementing material by taking a sulfate activator as a main part and a base activator as an auxiliary part, adding a filling aggregate to prepare a cemented filling body, and performing orthogonal tests on the 3d and 7d strength of the cemented filling body under the high-temperature curing condition; designing a formula of a base exciting agent by adopting a range analysis method of an orthogonal test, thereby obtaining an optimized formula of the base exciting agent;

(2) preparing a basic group activator filling cementing material by taking a basic group activator as a main part and a sulfate activator as an auxiliary part, adding a filling aggregate to prepare a cemented filling body, and performing orthogonal tests on the 3d and 7d strength of the cemented filling body under the high-temperature curing condition; designing a base excitant formula by adopting a range analysis method of an orthogonal test, thereby obtaining an optimized formula of the base excitant;

(3) obtaining a base activator optimized formula and a base activator optimized formula according to the steps (1) and (2), determining the orthogonal test design of the composite activator formula of the filling cementing material, and performing 7d and 28d strength orthogonal tests on the cemented filling body under the standard curing condition; and (3) performing stepwise regression analysis on the test data by using a quadratic polynomial, and establishing a cemented filling body strength model:

R _7d=F ₁ (X)、R _28d=F ₂ (X)

in the formula (I), the compound is shown in the specification,R _7drepresenting the strength of the cemented filling mass 7d,F ₁(X) Representing a cemented filling body 7d strength model;R _28drepresents the strength of the cemented filling body 28 d;F ₂(X) Representing a cemented pack 28d strength model;

establishing a filled cementing material cost model according to the raw material cost of the filled cementing material and the ratio of the filled cementing material:C _T=F ₃(X)

in the formula (I), the compound is shown in the specification,C _Trepresents the cost of the filled cementitious material;F ₃(X) Representing a filled cementitious material cost model;

X ={x ₁, x ₂, …, x _n}^Trepresenting a filling cementing material composite excitant variable;

(4) the cost of the composite excited filling cementing material is taken as an optimization target, the strength of the cemented filling bodies 7d and 28d is taken as a constraint condition, and a low-cost filling cementing material proportion optimization model is established as follows:

optimizing the target:MinC _T = Min F ₃(X)

constraint conditions are as follows:R _7d=F ₁ (X)≥[R _7d]；R _28d=F ₂ (X)≥[R _28d]

in the formula (2)R _7d]、[R _28d]Respectively designing strength indexes for the cemented filling bodies 7d and 28d by a filling mining method;

by solving the optimization model, the optimized formula of the composite exciting agent with the lowest filling cementing material cost can be obtained, and therefore the low-cost filling cementing material meeting the filling mining requirements can be prepared.

2. The design method of the low-cost composite excitation filling cementing material according to claim 1, is characterized in that: in the step (1), the formula of the salt-based activator cementing material is as follows: 13-17wt% of sulfate excitant, 2-6wt% of base excitant, 0-1.0 wt% of industrial mirabilite and the balance of slag micro powder.

3. The design method of the low-cost composite excited filling cementing material according to the claim 2, characterized in that, in the step (2), the formulation of the base excitant filling cementing material is as follows: 8-12wt% of basic group excitant, 2-6wt% of sulfate excitant, 0-1.0 wt% of industrial mirabilite and the balance of slag micro powder.

4. The design method of the low-cost composite excited filling cementing material according to the claim 3, characterized in that, in the steps (1) and (2), the sulfate excitant is desulfurized gypsum, and the water content of the powder is<8wt%、SO₃Content (wt.)>38wt% and fineness of powder<15%。

5. The design method of the low-cost composite excited filling cementing material according to the claim 4, characterized in that in the steps (1) and (2), the basic group excitant is cement clinker and quicklime, the fineness of the powder is less than 5wt%, and the CaO content is more than 80 wt%.

6. The design method of the low-cost composite excited filling cementing material according to the claim 5, characterized in that in the steps (1) and (2), the high-temperature curing conditions are as follows: the temperature is 38-42 ℃, and the humidity is more than or equal to 95 percent.

7. The method for designing low-cost composite excited filling cementing material according to claim 6, wherein in the step (3), the ratio of the sulfate activator in the formula of the composite activator is preferably determined according to the ratio of the salt activator in the step (1)The ratio of the sulfate excitant in the formula is floated up and down by 1-2% to determine the test range, and the ratio of the base excitant in the optimized formula of the base excitant in the step (2) is floated up and down by 1-2% to determine the test range; i.e. A = A₁±（1-2%），B=B₂±（1-2%）；

A is the proportion of sulfate excitant in the formula of the composite excitant, A₁Optimizing the proportion of the sulfate excitant in the formula for the base excitant in the step (1); b is the base activator proportion in the formula of the compound activator, B₂Optimizing the proportion of the base exciting agent in the formula for the base exciting agent in the step (2).

8. The method as claimed in claim 7, wherein in step (3), the strength test method is performed according to GB/T17671-1999 Cement mortar Strength test method (ISO method).

9. The method for designing the low-cost composite activated filling cementing material according to any one of the claims 1 to 8, which is characterized by further comprising the steps of carrying out strength verification and cost analysis on the cemented filling body of the formula of the composite activated filling cementing material obtained in the step (4).

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