阅读说明：本技术 一种灌注桩用水泥及其制备方法 (Cement for cast-in-place pile and preparation method thereof ) 是由 窦霆 张青青 于 2020-05-27 设计创作，主要内容包括：本发明涉及水泥技术领域,具体而言,涉及一种灌注桩用水泥及其制备方法。一种灌注桩用水泥,包括如下重量份数的组分：水泥熟料40～60份、脱硫石膏3～6份、超细灰12～18份和复合矿渣微粉25～35份；所述复合矿渣微粉包括如下质量百分比的组分；矿渣75％～85％、陶瓷废料13.5％～24.5％和副产元明粉0.5％～1.5％；所述超细灰主要由如下质量百分比的原料制备得到：灰渣65％～80％、粉煤灰18.8％～34.2％和副产元明粉0.8％～1.2％。本发明的灌注桩用水泥具有优异的抗折强度和抗压强度,抗渗效果好,抗化学腐蚀能力优异。(The invention relates to the technical field of cement, in particular to cement for a cast-in-place pile and a preparation method thereof. The cement for the cast-in-place pile comprises the following components in parts by weight: 40-60 parts of cement clinker, 3-6 parts of desulfurized gypsum, 12-18 parts of superfine ash and 25-35 parts of composite slag micro powder; the composite slag micro powder comprises the following components in percentage by mass; 75 to 85 percent of slag, 13.5 to 24.5 percent of ceramic waste and 0.5 to 1.5 percent of byproduct anhydrous sodium sulphate; the superfine ash is mainly prepared from the following raw materials in percentage by mass: 65 to 80 percent of ash, 18.8 to 34.2 percent of fly ash and 0.8 to 1.2 percent of sodium sulfate byproduct. The cement for the cast-in-place pile has excellent breaking strength and compressive strength, good anti-permeability effect and excellent chemical corrosion resistance.)

1. The cement for the cast-in-place pile is characterized by comprising the following components in parts by weight:

40-60 parts of cement clinker, 3-6 parts of desulfurized gypsum, 12-18 parts of superfine ash and 25-35 parts of composite slag micro powder;

the composite slag micro powder comprises the following components in percentage by mass; 75 to 85 percent of slag, 13.5 to 24.5 percent of ceramic waste and 0.5 to 1.5 percent of byproduct anhydrous sodium sulphate;

the superfine ash is mainly prepared from the following raw materials in percentage by mass: 65 to 80 percent of ash, 18.8 to 34.2 percent of fly ash and 0.8 to 1.2 percent of sodium sulfate byproduct.

2. The cement for the cast-in-place pile as claimed in claim 1, which is characterized by comprising the following components in parts by weight:

45-50 parts of cement clinker, 4-5 parts of desulfurized gypsum, 14-16 parts of superfine ash and 27-33 parts of composite slag micro powder;

the composite slag micro powder comprises the following components in percentage by mass; 78 to 82 percent of slag, 17.2 to 21 percent of ceramic waste and 0.8 to 1 percent of anhydrous sodium sulphate byproduct;

the superfine ash is mainly prepared from the following raw materials in percentage by mass: 70 to 75 percent of ash, 24.1 to 29 percent of fly ash and 0.9 to 1 percent of anhydrous sodium sulphate as a byproduct.

3. The cement for the cast-in-place pile according to claim 1 or 2, wherein the ash comprises the following components in percentage by mass: SiO 2₂48.86％～53.88％、Al₂O₃35％～40％、Fe₂O₃5％～6％、CaO 4％～5％、MgO0.9％～1.1％、SO₃0.02％～0.04％；

The fly ash comprises the following components in percentage by mass: SiO 2₂55％～62.8％、Al₂O₃27％～34.8％、Fe₂O₃5％～6％、CaO 3％～4％、MgO 0.8％～0.9％、SO₃0.3％～0.4％；

The byproduct anhydrous sodium sulphate comprises the following components in percentage by mass: SiO 2₂52％～57.8％、Al₂O₃33％～39.1％、Fe₂O₃5％～6％、CaO 1％～2％、MgO 1％～1.5％、SO₃0.7％～0.9％。

4. The cement for the cast-in-place pile according to claim 3, wherein the water content of the superfine ash raw material is 10-15%;

preferably, the water content of the ash raw material is 9-15%;

preferably, the water content of the fly ash raw material is 2.5-8%.

5. The cement for cast-in-place piles according to claim 1 or 2, wherein the preparation method of the ultra-fine ash comprises: mixing and grinding ash, fly ash and a byproduct anhydrous sodium sulphate;

preferably, the grinding time is 10-20 min;

preferably, the specific surface area of the superfine ash is 480-520 m²/kg。

6. The cement for cast-in-place piles according to claim 1 or 2, wherein the specific surface area of the composite slag micro powder is 460 to 470m²/kg。

7. The cement for cast-in-place piles according to claim 1 or 2, having a specific surface area of 450 to 500m²/kg。

8. A method for preparing cement for a cast-in-place pile according to any one of claims 1 to 7, characterized by comprising the steps of:

mixing and grinding cement clinker, desulfurized gypsum, superfine ash and composite slag micropowder.

9. The method for preparing cement for cast-in-place piles according to claim 8, comprising the steps of:

mixing and grinding cement clinker, desulfurized gypsum and superfine ash until the specific surface area of the powder is 340-400 m²And/kg, adding the composite slag micro powder and uniformly mixing.

10. The method for preparing cement for a cast-in-place pile according to claim 9, wherein the time for mixing and grinding the clinker, the desulfurized gypsum and the ultrafine ash is 10-30 min.

Technical Field

The invention relates to the technical field of cement, in particular to cement for a cast-in-place pile and a preparation method thereof.

Background

The cast-in-place pile is a pile formed by forming a hole in place and pouring concrete or reinforced concrete. The cast-in-place pile can be classified into a cast-in-place pile, a manually-excavated cast-in-place pile, an explosion-expanded cast-in-place pile, etc. according to the method of forming the hole. The existing cast-in-place pile engineering has higher requirements on the strength, chemical corrosion resistance, impermeability and corrosion resistance of a cementing material. The most widely used at present is general portland cement which has the following disadvantages: the generated hydration heat is large, the sulfate corrosion resistance is poor, the impermeability is poor, the compactness is low, and the like.

In view of the above, the present invention is particularly proposed.

Disclosure of Invention

An object of the present invention is to provide a cement for cast-in-place piles, which can improve the retarding effect of the obtained cement, enhance the compression resistance effect, the fracture resistance effect, the anti-permeability effect, etc. of the cement through the cooperation of clinker, desulfurized gypsum, ultra-fine ash and composite slag micro powder.

The invention also aims to provide a preparation method of the cement for the cast-in-place pile, which is simple and feasible, and is energy-saving and environment-friendly.

In order to achieve the above purpose of the present invention, the following technical solutions are adopted:

the cement for the cast-in-place pile comprises the following components in parts by weight:

40-60 parts of cement clinker, 3-6 parts of desulfurized gypsum, 12-18 parts of superfine ash and 27-33 parts of composite slag micro powder;

the composite slag micro powder comprises the following components in percentage by mass; 75 to 85 percent of slag, 13.5 to 24.5 percent of ceramic waste and 0.5 to 1.5 percent of byproduct anhydrous sodium sulphate;

the superfine ash is mainly prepared from the following raw materials in percentage by mass: 65 to 80 percent of ash, 18.8 to 34.2 percent of fly ash and 0.8 to 1.2 percent of sodium sulfate byproduct.

Preferably, the cement for the cast-in-place pile comprises the following components in parts by weight:

45-50 parts of cement clinker, 4-5 parts of desulfurized gypsum, 14-16 parts of superfine ash and 27-33 parts of composite slag micro powder;

the composite slag micro powder comprises the following components in percentage by mass; 78 to 82 percent of slag, 17.2 to 21 percent of ceramic waste and 0.8 to 1 percent of anhydrous sodium sulphate byproduct;

the superfine ash is mainly prepared from the following raw materials in percentage by mass: 70 to 75 percent of ash, 24.1 to 29 percent of fly ash and 0.9 to 1 percent of anhydrous sodium sulphate as a byproduct.

Preferably, the ash comprises the following components in percentage by mass: SiO 2₂48.86％～53.88％、Al₂O₃35％～40％、Fe₂O₃5％～6％、CaO 4％～5％、MgO 0.9％～1.1％、SO₃0.02％～0.04％；

The fly ash comprises the following components in percentage by mass: SiO 2₂55％～62.8％、Al₂O₃27％～34.8％、Fe₂O₃5％～6％、CaO 3％～4％、MgO 0.8％～0.9％、SO₃0.3％～0.4％；

The byproduct anhydrous sodium sulphate comprises the following components in percentage by mass: SiO 2₂52％～57.8％、Al₂O₃33％～39.1％、Fe₂O₃5％～6％、CaO 1％～2％、MgO 1％～1.5％、SO₃0.7％～0.9％。

Preferably, the water content of the superfine ash raw material is 10-15%;

preferably, the water content of the ash raw material is 9-15%;

preferably, the water content of the fly ash raw material is 2.5-8%.

Preferably, the preparation method of the ultrafine ash comprises the following steps: mixing and grinding ash, fly ash and a byproduct anhydrous sodium sulphate;

preferably, the grinding time is 10-20 min;

preferably, the specific surface area of the superfine ash is 480-520 m²/kg。

Preferably, the specific surface area of the composite slag micro powder is 460-470 m²/kg。

Preferably, the specific surface area of the cement for the cast-in-place pile is 450-500 m²/kg。

The preparation method of the cement for the cast-in-place pile comprises the following steps:

mixing and grinding cement clinker, desulfurized gypsum, superfine ash and composite slag micropowder.

Preferably, the preparation method of the cement for the cast-in-place pile comprises the following steps:

mixing and grinding cement clinker, desulfurized gypsum and superfine ash until the specific surface area of the powder is 340-400 m²And/kg, adding the composite slag micro powder and uniformly mixing.

Preferably, the time for mixing and grinding the clinker, the desulfurized gypsum and the superfine ash is 10-30 min.

Compared with the prior art, the invention has the beneficial effects that:

(1) the specific superfine ash can increase the corrosion resistance of cement and concrete and has the effect of delaying the setting time; the specific composite slag micro powder can increase the compactness of cement and concrete; through the cooperation of the clinker, the desulfurized gypsum, the ultrafine ash and the composite slag micro powder, the retarding effect of the obtained cement can be improved, and the compression resistance effect, the folding resistance effect, the anti-permeability effect, the chemical corrosion resistance and the like of the cement are enhanced.

(2) The preparation method of the cement for the cast-in-place pile is simple and feasible, and is energy-saving and environment-friendly.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to examples, but it will be understood by those skilled in the art that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products commercially available.

The cement for the cast-in-place pile comprises the following components in parts by weight:

40-60 parts of cement clinker, 3-6 parts of desulfurized gypsum, 12-18 parts of superfine ash and 27-33 parts of composite slag micro powder;

the composite slag micro powder comprises the following components in percentage by mass; 75 to 85 percent of slag, 13.5 to 24.5 percent of ceramic waste and 0.5 to 1.5 percent of byproduct anhydrous sodium sulphate;

the superfine ash is mainly prepared from the following raw materials in percentage by mass: 65 to 80 percent of ash, 18.8 to 34.2 percent of fly ash and 0.8 to 1.2 percent of sodium sulfate byproduct.

The invention aims to solve the problems of large hydration heat, poor sulfate corrosion resistance, poor impermeability, low compactness and the like caused by applying general portland cement in pile foundation engineering, and simultaneously solve the problems of land occupation, environment pollution and the like of local industrial waste residues. The invention adopts the cooperation of cement clinker, desulfurized gypsum, superfine ash and composite slag micro powder, can enhance the compression resistance effect, the folding resistance effect, the anti-permeability effect and the like of cement, adjusts the corresponding setting time according to different transport distances and air temperatures, not only ensures the construction period not to be delayed, but also avoids the quality accident of concrete advanced setting which is possibly caused after the engineering transport distance is extended.

In one embodiment, the cement clinker is 40-60 parts, and 41 parts, 42 parts, 43 parts, 44 parts, 45 parts, 46 parts, 47 parts, 48 parts, 49 parts, 50 parts, 51 parts, 52 parts, 53 parts, 54 parts, 55 parts, 56 parts, 57 parts, 58 parts or 59 parts can be selected.

In one embodiment, the desulfurized gypsum is 3 to 6 parts, and may be 3.2 parts, 3.5 parts, 3.7 parts, 4 parts, 4.2 parts, 4.5 parts, 4.7 parts, 5 parts, 5.2 parts, 5.5 parts, 5.7 parts, or 5.9 parts.

In one embodiment, the superfine ash is 12-18 parts, and can be selected from 12.5 parts, 13 parts, 13.5 parts, 14 parts, 14.5 parts, 15 parts, 15.5 parts, 16 parts, 16.5 parts, 17 parts or 17.5 parts.

In one embodiment, 27 to 33 parts of the composite slag micro powder can be 27.5 parts, 28 parts, 28.5 parts, 29 parts, 29.5 parts, 30 parts, 30.5 parts, 31 parts, 31.5 parts, 32 parts or 32.5 parts.

The specific superfine ash has the characteristics of large specific surface area, increased pile foundation compactness, improved strength absolute value, low ignition loss, reduced concrete slump, small water demand and the like.

In one embodiment, the ash is 65% to 80% by mass. 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79% or 80% may also be selected.

In one embodiment, the fly ash accounts for 18.8-34.2% by mass, and can also be 19%, 20%, 21%, 25%, 27%, 28%, 30%, 31% or 34% by mass.

In one embodiment, the byproduct anhydrous sodium sulfate is 0.8-1.2% by mass, and may be 0.9%, 1%, 1.1% or 1.2% by mass.

The specific composite slag micro powder takes slag as a main raw material, ceramic waste as an auxiliary material and a byproduct of anhydrous sodium sulphate as an excitant, greatly improves the activity of the composite mineral powder, utilizes local industrial waste, effectively prevents chloride ions from permeating and has high corrosion resistance. Makes contribution to the environmental pollution treatment, saves cost for enterprises, improves profit margin and creates a brand new way for the industrial solid waste treatment.

In one embodiment, the ash slag is 75-85% by mass, and may be selected from 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83% or 84%.

In one embodiment, the ceramic waste is 13.5% to 24.5%, and may be selected from 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, or 24% by mass.

In one embodiment, the by-product anhydrous sodium sulphate is 0.5-1.5% by mass, and may be selected from 0.6%, 0.7%, 0.8%, 1%, 1.1%, 1.2%, 1.3% or 1.4%.

Preferably, the cement for the cast-in-place pile comprises the following components in parts by weight:

45-50 parts of cement clinker, 4-5 parts of desulfurized gypsum, 14-16 parts of superfine ash and 27-33 parts of composite slag micro powder;

the composite slag micro powder comprises the following components in percentage by mass; 78 to 82 percent of slag, 17.2 to 21 percent of ceramic waste and 0.8 to 1 percent of anhydrous sodium sulphate byproduct;

the superfine ash is mainly prepared from the following raw materials in percentage by mass: 70 to 75 percent of ash, 24.1 to 29 percent of fly ash and 0.9 to 1 percent of anhydrous sodium sulphate as a byproduct.

By further optimizing the proportion of the cement clinker, the desulfurized gypsum, the ultrafine ash and the composite slag micro powder and the proportion of the raw materials of the ultrafine ash and the composite slag micro powder, the retarding effect of the obtained cement can be better improved, the compression resistance effect, the folding resistance effect, the anti-permeability effect and the like of the cement are enhanced, and the cement for cast-in-place pile engineering can be better satisfied.

Preferably, the ash comprises the following components in percentage by mass: SiO 2₂48.86％～53.88％、Al₂O₃35％～40％、Fe₂O₃5％～6％、CaO 4％～5％、MgO 0.9％～1.1％、SO₃0.02％～0.04％；

The fly ash comprises the following components in percentage by mass: SiO 2₂55％～62.8％、Al₂O₃27％～34.8％、Fe₂O₃5％～6％、CaO 3％～4％、MgO 0.8％～0.9％、SO₃0.3％～0.4％；

The byproduct anhydrous sodium sulphate comprises the following components in percentage by mass: SiO 2₂52％～57.8％、Al₂O₃33％～39.1％、Fe₂O₃5％～6％、CaO 1％～2％、MgO 1％～1.5％、SO₃0.7％～0.9％。

The ultrafine ash of the present invention further contains inevitable impurities.

In one embodiment, the ash comprises the following components in percentage by mass: SiO 2₂50.5％、Al₂O₃336.55％、Fe₂O₃5.57％、CaO 4.19％、MgO 1％、SO₃0.02 percent; the loss on ignition was 2.80% and the moisture content was 9.2%.

In one embodiment, the fly ash comprises the following components in percentage by mass: SiO 2₂55.89％、Al₂O₃27.68％、Fe₂O₃5.35％、CaO 3.51％、MgO 0.85％、SO₃0.31 percent; the loss on ignition was 2.50% and the water content was 2.7%.

In one embodiment, the by-product anhydrous sodium sulfate comprises the following components in percentage by mass: SiO 2₂53.59％、Al₂O₃33.49％、Fe₂O₃5.52％、CaO 1.55％、MgO 1.3％、SO₃0.83 percent; the loss on ignition was 4%.

Preferably, the water content of the ultra-fine ash raw material is 10-15%.

Preferably, the water content of the ash raw material is 9-15%;

preferably, the water content of the fly ash raw material is 2.5-8%.

Preferably, the preparation method of the ultrafine ash comprises the following steps: mixing and grinding ash, fly ash and a byproduct anhydrous sodium sulphate;

preferably, the grinding time is 10-20 min;

preferably, the specific surface area of the superfine ash is 480-520 m²/kg。

The method has simple process, is suitable for mass production, and has low production cost.

The crushing device comprises a vertical mill. The vertical mill is a device integrating crushing, drying, grinding and grading conveying, and has high production efficiency and low drying cost.

The invention can ensure the water content to be 10-15% by controlling the water content of the ash raw material and the fly ash raw material and matching with the byproduct anhydrous sodium sulphate, further reduce the subsequent drying cost and save energy.

The water demand ratio of the superfine ash is 95-96%, and the loss on ignition is 3-4%.

Preferably, the specific surface area of the composite slag micro powder is 460-470 m²/kg。

Preferably, the specific surface area of the cement for the cast-in-place pile is 450-500 m²/kg。

The preparation method of the cement for the cast-in-place pile comprises the following steps:

mixing and grinding cement clinker, desulfurized gypsum, superfine ash and composite slag micropowder.

The preparation method of the cement for the cast-in-place pile is simple and feasible, and is energy-saving and environment-friendly.

Preferably, the preparation method of the cement for the cast-in-place pile comprises the following steps:

mixing and grinding the clinker, the desulfurized gypsum and the superfine ash until the specific surface area of the powder is 340-400 m²And/kg, adding the composite slag micro powder and uniformly mixing.

Mixing and grinding the clinker, the desulfurized gypsum and the superfine ash until the specific surface area of the powder is 340-400 m²And/kg, adding the composite slag micro powder, stirring and mixing uniformly through a double shaft, and preparing the cement for the cast-in-place pile through a homogenization mode of pneumatic conveying and multi-warehouse matching.

Preferably, the time for mixing and grinding the clinker, the desulfurized gypsum and the superfine ash is 10-30 min.

In one embodiment, the time for mixing and grinding the clinker, the desulfurized gypsum and the superfine ash is 10-30 min, and can be selected from 12min, 15min, 17min, 20min, 22min, 25min and 27 min.

The present invention will be further explained with reference to specific examples and comparative examples.