CN114591034B

CN114591034B - Compression strength enhanced type muck building block and preparation method thereof

Info

Publication number: CN114591034B
Application number: CN202210182102.4A
Authority: CN
Inventors: 陈刚
Original assignee: Shenzhen Hezhicheng Environmental Protection Building Materials Co ltd
Current assignee: Shenzhen Hezhicheng Environmental Protection Building Materials Co ltd
Priority date: 2022-02-26
Filing date: 2022-02-26
Publication date: 2022-09-30
Anticipated expiration: 2042-02-26
Also published as: CN114591034A

Abstract

The invention relates to the technical field of building materials, and particularly discloses a compressive strength enhanced muck block and a preparation method thereof, wherein the compressive strength enhanced muck block is prepared from the following raw materials in parts by weight: 1500 parts of slag soil, 1000 parts of sand, 700 parts of sand, 950 parts of cement, 290 parts of fly ash, 320 parts of basalt fiber, 150 parts of composite reinforcing agent, 8-12 parts of polyurethane adhesive, 35-45 parts of water reducing agent and 570 parts of water, 510; each part of the composite reinforcing agent consists of a nano molecular sieve, alginate fibers and aminopropyltrimethoxysilane, wherein the weight ratio of the nano molecular sieve to the alginate fibers to the aminopropyltrimethoxysilane is 3-20: 1.7-5: 1; the preparation method comprises the following steps: pretreating, premixing and mixing the dregs to prepare blocks. The compression strength enhanced type muck block disclosed by the invention has the advantages of high strength and environmental friendliness.

Description

Compression strength enhanced type muck building block and preparation method thereof

Technical Field

The invention relates to the technical field of building materials, in particular to a compression strength enhanced type muck block and a preparation method thereof.

Background

The engineering residual soil is one kind of building garbage, and generally refers to waste soil, waste materials and other wastes generated in the process of building construction units, new construction, reconstruction, demolition of buildings and structures and house decoration. Along with the development of social construction, the amount of engineering muck is gradually increased, and direct landfill treatment not only causes soil pollution but also causes resource waste.

The related technology is seen in a patent with application publication number CN107500649A, which discloses a baking-free slag-soil brick and a preparation method and application thereof, wherein the preparation method of the baking-free slag-soil brick comprises the following steps: mixing cement, muck and other additives with water to obtain a mixture; and forming the mixture, and curing at 25-30 ℃ to obtain the clinker-free clay brick.

In view of the above-mentioned related art, the manufactured residue soil brick is used as a non-load-bearing brick or a low-load-bearing pedestrian pavement brick, however, in practical application, the force loaded on the residue soil brick exceeds the expected phenomenon, so that the building structure or structure is easy to crack.

Disclosure of Invention

Aiming at the problem that the load-bearing capacity of the manufactured muck brick is low due to the strength in the prior art, the invention aims to provide the muck brick with enhanced compressive strength.

The second purpose of the invention is to provide a preparation method of the slag soil building block with enhanced compressive strength, and the preparation method has the advantage of stably manufacturing the slag soil building block with high compressive strength.

In order to achieve the first object, the invention provides the following technical scheme:

the compression strength enhanced muck block comprises the following raw materials in parts by weight: 1500 parts of slag soil, 1000 parts of sand, 700 parts of sand, 950 parts of cement, 290 parts of fly ash, 320 parts of basalt fiber, 150 parts of composite reinforcing agent, 8-12 parts of polyurethane adhesive, 35-45 parts of water reducing agent and 570 parts of water, 510;

each part of the composite reinforcing agent consists of a nano molecular sieve, alginate fibers and aminopropyltrimethoxysilane, wherein the weight ratio of the nano molecular sieve to the alginate fibers to the aminopropyltrimethoxysilane is 3-20: 1.7-5:1.

Further, the raw materials comprise: 1300 parts of slag soil, 950 parts of sand, 900 parts of cement, 310 parts of fly ash, 30-35 parts of basalt fiber, 135 parts of composite reinforcing agent, 9-11 parts of polyurethane adhesive, 38-42 parts of water reducing agent and 560 parts of water 530;

preferably, the raw materials comprise: 1300 parts of muck, 1000 parts of sand, 900 parts of cement, 300 parts of fly ash, 35 parts of basalt fiber, 130 parts of composite reinforcing agent, 10 parts of polyurethane adhesive, 40 parts of water reducing agent and 550 parts of water.

Further, the weight ratio of the nano molecular sieve, the alginate fiber and the aminopropyltrimethoxysilane is 4-7: 1.7-2: 1.

by adopting the technical scheme, the nano molecular sieve can permeate into loose pores in the residue soil when being mixed with the residue soil under the drive of the aqueous solution. During the stirring and mixing process of the muck and the nano molecular sieve, part of heavy metals contained in the muck are dissolved out, and part of the dissolved heavy metals are absorbed by the nano molecular sieve.

In the drying process, the alginate fibers are attached to the surface of the nano molecular sieve, and in the drying process of the alginate fibers and aminopropyltrimethoxysilane, amino groups on the aminopropyltrimethoxysilane react with hydroxyl groups on the surface of the alginate fibers, so that the alginate fibers form a net structure, nanoparticles in the nano molecular sieve can be locked in pores in the muck, the nanoparticles in the pores of the muck are prevented from dissociating from the pores, and the toughness of the product is improved. In addition, another part of the dissolved heavy metals are chelated with hydroxyl on the alginate fiber or amino on aminopropyltrimethoxysilane. The alginate fibers form a net structure to lock the nano particles, and simultaneously lock the heavy metals, so that the phenomenon that the heavy metals in the residue soil building block in later use overflow to the outside and exceed the standard is reduced, and a green building material is formed.

Due to the action of the nano particles, when the muck is subjected to external force in the stirring impact process and later period, the stress concentration effect is generated due to the existence of the nano particles, so that the alginate fibers and the polyurethane adhesive generate micro cracks to absorb certain deformation work, and meanwhile, the matrix among the nano particles also generates yield and plastic deformation to absorb impact energy, and the crack expansion of the alginate fibers and the polyurethane adhesive is hindered and passivated due to the existence of the nano particles. Thereby increasing the impact strength of the muck block as a whole.

Further, the residue soil is mixed and stirred by the composite reinforcing agent water solution and then is dried and pretreated.

Further, the water reducing agent is a lignosulfonate water reducing agent.

By adopting the technical scheme, the impermeability and frost resistance of the muck block can be improved and the bleeding property can be reduced in the process of manufacturing the muck block.

In order to achieve the second object, the invention provides the following technical scheme:

a preparation method of a compression strength enhanced type muck block comprises the following steps:

s1, pre-treating the residue soil: adding water into the composite reinforcing agent, uniformly mixing to form a mixed solution, pouring the muck into the mixed solution, fully stirring, and drying to form a muck reinforcement;

s2, premixing: fully mixing sand, fly ash, basalt fiber and a slag reinforcement to form a premix;

s3, mixing and briquetting: stirring water, a water reducing agent and a polyurethane adhesive, adding the premix, uniformly stirring and mixing, adding the cement into the premix, fully stirring, forming a blank body in a mold after uniformly stirring, and curing and molding the blank body into the muck block.

Further, in the step S1, the concentration of the composite reinforcing agent in the mixed solution is 15% to 25%; preferably, the concentration of the composite reinforcing agent is 20%.

By adopting the technical scheme, in the slag soil pretreatment process, the reaction rate of the alginate fibers and the aminopropyl trimethoxy silane is higher, the reaction is more sufficient, the occupation of excessive aminopropyl trimethoxy silane on the internal pores of the slag soil in the drying process is reduced, the slag soil is more compact after pretreatment, and the strength of the slag soil building block is improved.

Further, in the step S1, the drying temperature of the muck enhancer is 60-120 ℃, and the drying time is 140-200 min.

By adopting the technical scheme, the residue soil reinforcement has more proper reaction conditions with aminopropyltrimethoxysilane while being dried, the modification rate of the alginate fibers is improved, the locking effect on nano particles is increased, and the toughness of the residue soil building block is improved.

Further, in the step S3, the stirring time is 5 to 10min before the cement is added, and the stirring time is 5 to 8min after the cement is added.

By adopting the technical scheme, the tissues of all parts are uniformly mixed, the strength stability of the same batch of produced muck blocks is improved, the fluctuation is reduced, and the rejection rate is reduced.

In conclusion, the invention has the following beneficial effects:

1. the slag soil building block has high strength and good stability, is easy to produce and control quality, prolongs the service life and improves the market competitiveness;

2. the heavy metal dissolving-out capability is lower, and the environmental protection performance of the slag soil brickwork is improved.

Detailed Description

In general, the production of the residue soil building block is to further crush the recovered residue soil to form the required particle size, then to mix with other aggregates including cement, to add water and harden to form the residue soil building block. In the traditional manufacturing mode, the phenomenon that the mechanical strength fluctuation range of the same batch of muck blocks is large so that the product performance of the factory-leaving identification product is generated is found: uniformly labeling according to the lowest detection value, namely, the detection value is more than or equal to X, wherein X represents the lowest performance value of the same batch of samples to be inspected. This results in the performance of the product being determined by the lowest value, which affects the quality improvement of the product. The applicant found in research and analysis that: because the dregs are generally products after engineering breaking, the breaking process of the dregs comprises mechanical breaking or explosive blasting, and in the breaking process of the original building or structure, high impact is applied to the dregs, so that microcracks exist in the dregs in the raw materials, and part of the dregs can be loosened or holes are generated in the dregs due to early erosion and weathering. When the content of the muck with microcracks in the manufactured muck building blocks is high, the strength of the muck building blocks is relatively low; when the content of the slag soil with microcracks in the slag soil building block is low, the strength of the slag soil building block is relatively high. Based on the method, when the applicant pretreats the muck raw materials through the composite reinforcing agent with special proportion and then manufactures the muck building blocks, the mechanical strength of the muck building blocks is integrally and obviously improved, the fluctuation range of the detected mechanical strength of the same batch of muck building blocks is small, performance index control is convenient to carry out, the strength identification of the ex-factory muck building blocks is improved, the rejection rate of products is reduced, the detected heavy metal is dissolved out less, and the method is green and environment-friendly.

The present invention will be described in further detail with reference to examples.

Examples

The raw materials of the present invention are all commercially available, and the specification and model of the raw materials are shown in table 1.

TABLE 1 Specification and model table of raw materials

Name of raw materials	Specification and model
		Alginate fiber	Diameter of 1.6um and length of 2mm
Aminopropyl trimethoxysilane	Super, FD-551
		Nano Beta molecular sieve	XFF13 with crystal grain of 26.7nm
Fly ash	First order, not more than 100um
		Cement	P.042.5R
Lignosulfonate water reducing agent	Technical grade, sodium lignosulfonate
		Basalt fiber	First grade product with length of 5mm
Polyurethane adhesive	Bag for containing liquid medicine

In the following examples, the slag soil is common engineering slag soil, mainly brick-concrete structure building waste, and the sand is machine-made sand for crushing granite. Primarily crushing the residue soil to remove the contained steel bars and iron wires, then crushing until the particle size is not more than 20mm, magnetically separating again to discharge metal particles, and screening the residue soil with the particle size of 5-20mm for use. And crushing the machine-made sand to be not more than 3mm, and screening out a part within 3mm for use.

Example 1: a preparation method of a compression strength enhanced type muck block comprises the following steps:

s1, pre-treating the dregs: uniformly mixing 8kg of nano molecular sieve, 3.2kg of alginate fiber and 1.8kg of aminopropyltrimethoxysilane, adding water, uniformly stirring at 200r/min to enable the mass fraction of the composite reinforcing agent to be 20%, adding 130kg of muck particles, stirring again for 30min, and then transferring the mixed materials into a drying furnace to dry for 150min at 90 ℃ to form a muck reinforcement.

S2, premixing: taking 100kg of sand, 30kg of fly ash, 35kg of basalt fiber and the muck reinforcement obtained in the step S1, and fully mixing to form a premix;

s3, mixing and briquetting: uniformly stirring 55kg of water, 4kg of water reducing agent and 1kg of polyurethane adhesive at the speed of 200r/min, adding the premix obtained in the step S2, stirring for 5min, adding 90kg of cement, continuously stirring for 8min, forming a blank in a mold after uniformly stirring, and curing and hardening the blank into the muck block at room temperature.

Examples 2 to 10

Examples 2 to 10 are different from example 1 in the amount of each raw material added, and the amount of each raw material added is shown in Table 2.

TABLE 2 addition of each raw material in examples 2 to 10

Examples 11 to 14

Examples 11-14 differ from example 1 in the process parameters for each step of examples 11-14, which are shown in Table 3.

Table 3 table of process parameters for examples 11-14

Comparative example 1

A method for preparing a compressive strength reinforced concrete, which is different from example 1 in that the muck is not pretreated, and all the raw materials are mixed directly in step S2.

Comparative example 2

The difference between the preparation method of the compressive strength reinforced concrete and the embodiment 1 is that the dosage of the nano molecular sieve in the step S1 is 0.5 kg.

Comparative example 3

The preparation method of the compressive strength reinforced concrete is different from the preparation method of the embodiment 1 in that the raw materials do not contain the nano molecular sieve.

Comparative example 4

The preparation method of the compressive strength reinforced concrete is different from the preparation method of the embodiment 1 in that the raw materials do not contain alginate fibers.

Comparative example 5

The preparation method of the compressive strength reinforced concrete is different from the preparation method of the embodiment 1 in that the raw materials do not contain aminopropyl trimethoxy silane.

Comparative example 6

The preparation method of the compressive strength reinforced concrete is different from the embodiment 1 in that the raw materials do not contain a composite reinforcing agent.

Comparative example 7

The difference between the preparation method of the concrete with the enhanced compressive strength and the embodiment 1 is that the raw materials do not contain polyurethane adhesive.

Comparative example 8

The preparation method of the compressive strength reinforced concrete is different from the embodiment 1 in that basalt fibers are not contained in raw materials.

Performance detection

Compressive strength: manufacturing a sample according to a national standard GB/T2542 wall brick test method and detecting;

breaking strength: manufacturing a sample according to a national standard GB/T2542 wall brick test method and detecting;

freeze-thaw strength loss rate: and (3) preparing a sample according to the national standard GB/T2542 wall brick test method and detecting.

And (3) the dissolution rate of heavy metals: after the muck blocks manufactured in each example and comparative example are molded, 10 blocks are taken out and soaked in 100L of water for 24H, then taken out after ultrasonic oscillation for 30min, and then the soaked water solution is sampled and concentrated by 10 times to measure the total iron and the total chromium. The results are shown in Table 4.

TABLE 4 contrast table for product performance test results of dregs building block

Note that: in table 4, the strength fluctuation is the difference between the maximum compressive strength and the minimum compressive strength of the same batch of samples.

According to the analysis of the experimental results of the embodiment 1 and the comparative example 1, the residue soil particles are pretreated by using the composite reinforcing agent, so that the mechanical strength of the residue soil block can be improved, and the elution amount of heavy metals in the residue soil block can be reduced. In the actual production process, the same batch of residue soil building blocks after the residue soil pretreatment is carried out by using the composite reinforcing agent, the strength stability is high, the lowest value of the compressive strength is not more than 1MPa compared with the average value, and the strength fluctuation is less than 2MPa and even can be controlled within 1.5 MPa.

The analysis of the experimental results of the examples 1 to 10 and the comparative examples 2 to 6 shows that the nano molecular sieve in the composite reinforcing agent has a remarkable influence on the strength improvement of the residue soil building block, and the alginate fibers and the aminopropyltrimethoxysilane have a synergistic effect on the strength improvement. Meanwhile, the heavy metal can be locked and fixed, and the dissolving-out capability of the heavy metal is reduced. Wherein the weight ratio of the nano molecular sieve, the alginate fiber and the aminopropyl trimethoxy silane is 3-20: 1.7-5:1, especially the weight ratio of the nano molecular sieve, the alginate fiber and the aminopropyl trimethoxy silane is 4-7: 1.7-2: 1, the heavy metal dissolution capacity is lower, and the environmental protection performance of the slag soil brickwork is improved.

The experimental results of the embodiment 1 and the embodiments 11 to 14 show that the strength of the manufactured residue soil block is improved and reduced, and the strength of the residue soil block after the residue soil particle pretreatment can be promoted at higher drying temperature and higher concentration of the prepared composite reinforcing agent when the addition amount of each raw material is the same and the parameter process of each step is different.

The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present invention.

Claims

1. The compression strength enhanced muck block is characterized by comprising the following raw materials in parts by weight: 1500 parts of slag soil, 1000 parts of sand, 700 parts of sand, 950 parts of cement, 290 parts of fly ash, 320 parts of basalt fiber, 150 parts of composite reinforcing agent, 8-12 parts of polyurethane adhesive, 35-45 parts of water reducing agent and 570 parts of water, 510;

2. The reinforced compressive strength muck block of claim 1, wherein the raw materials comprise: 1300 parts of slag soil 1200-5, 950 parts of sand 900-500, 900 parts of cement 850-25, 310 parts of fly ash 300-310, 30-35 parts of basalt fiber, 135 parts of composite reinforcing agent 120-135, 9-11 parts of polyurethane adhesive, 38-42 parts of water reducing agent and 560 parts of water 530-400.

3. The slag building block with enhanced compressive strength according to claim 1, wherein the weight ratio of the nano molecular sieve, the alginate fiber and the aminopropyltrimethoxysilane is 4-7: 1.7-2: 1.

4. the slag soil block with enhanced compressive strength of claim 1, wherein the water reducing agent is a lignosulfonate-based water reducing agent.

5. The method of making a compressive strength enhanced muck block of claim 1, comprising the steps of:

s3, mixing and briquetting: stirring water, a water reducing agent and a polyurethane adhesive, adding the premix, uniformly stirring and mixing, adding the cement into the premix, fully stirring, forming a blank body in a mould after uniformly stirring, and curing and molding the blank body into the muck block.

6. The method for preparing the compressive strength enhanced muck block as claimed in claim 5, wherein in the step S1, the concentration of the composite reinforcing agent in the mixed solution is 15-25%.

7. The method as claimed in claim 5, wherein in step S1, the drying temperature of the slag reinforcement is 60-120 ℃, and the drying time is 140-200 min.

8. The residual soil block with enhanced compressive strength according to claim 5, wherein in the step S3, the stirring time is 5-10min before the cement is added, and the stirring time is 5-8min after the cement is added.