Machine sprayable dry-mix mortar composition, machine sprayable dry-mix mortar, and preparation method, application and use method thereof

Abstract

The present invention relates to the technical field of dry-mixed mortars, and discloses a dry-mixed mortar composition that can be sprayed by a machine, a dry-mixed mortar that can be sprayed by a machine, and a preparation method, application, and use method thereof. The composition contains a first component having a particle size not greater than 0.075mm and a second component having a particle size greater than 0.075mm; the content mass ratio of the first component to the second component is 1:1-3, and based on the total mass of the second component, the content of the second component having a particle size not less than 1.18mm is 13-50wt%. The dry-mixed mortar product having good air-transport stability that can be prepared using the dry-mixed mortar composition provided by the present invention has excellent pumping performance after being made into wet mortar, and the pumping process is not easy to separate, so that the purpose of continuous pumping can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of dry-mix mortar, and in particular to a machine-sprayable dry-mix mortar composition, a machine-sprayable dry-mix mortar, and a preparation method, application, and use method thereof. Background Art

[0002] Plaster mortar is the most important supporting material in the construction process. Plaster mortar is mainly used for leveling walls or ceilings. Therefore, plaster mortar is one of the most widely used mortars in the construction process.

[0003] The traditional ordinary plastering mortar is mixed in an intermittent manner and is constructed by hand, and is not suitable for existing continuous mechanized construction equipment. In order to change the defects of traditional construction technology, adapt to the rapid development of society, improve construction efficiency, save labor costs, and shorten construction period, developing a plastering mortar that can be mechanized is the best choice to solve the above problems.

[0004] At present, the commonly used mechanized construction dry-mix plaster mortar mainly focuses on formulation research, and a small part of the research is on mechanized spraying methods.

[0005] CN103485521A discloses a mechanized spraying method for common premixed mortar, which includes the following steps: S1. Mixing common dry-mixed mortar once with a continuous mortar mixer and twice with a horizontal mixer to obtain wet mortar; S2. Using a mortar delivery pump to transport the wet mortar obtained in S1 to a mortar sprayer at a spraying site; S3. The wet mortar is delivered to a spray gun through the mortar sprayer, forming a mortar jet in front of the nozzle of the spray gun, and the mortar is continuously and evenly sprayed on the construction surface; S4. After conventional leveling and compacting, the plastering finish is completed; wherein, the mortar delivery pump described in S2 is a double-cylinder piston pump, which is composed of a working cylinder and a supplementary cylinder in parallel, and the compensation cylinder adjusts the displacement of the mortar in the working cylinder and discharges the mortar during the mortar suction stroke of the working cylinder; the distance between the nozzle of the spray gun described in S3 and the wall is controlled within the range of 50 to 150 mm; the injection pressure of the spraying described in S3 is controlled within the range of 0.15 to 0.20 MPa.

[0006] Although this method can achieve a convenient and efficient working method of the machine spraying system in the machine spraying plastering project using ordinary domestic premixed mortar materials and construction conditions, this method is an intermittent construction process and cannot achieve continuous mechanized construction.

[0007] CN106904914A discloses a machine-sprayed dry-mixed plaster mortar, whose main raw materials, calculated by mass, include 12% to 14% of 42.5 strength ordinary Portland cement, 16% to 24% of stone powder, 56% to 66% of machine-made medium sand, and 0% to 16% of machine-made coarse sand; its additives include 0.03% to 0.055% of cellulose ether, 0.005% to 0.015% of starch ether, and 0.02% to 0.05% of air-entraining agent.

[0008] Although the dry-mixed plaster mortar obtained by the above method has good water retention, strength and construction performance, it still cannot solve the problems of poor air delivery stability of the dry-mixed mortar, easy segregation during pumping and inability to pump continuously. Summary of the Invention

[0009] The purpose of the present invention is to overcome the problems of poor air delivery stability, easy segregation during pumping and inability to continuously pump dry-mix mortar in the prior art.

[0010] During their research, the inventors discovered that when a first component (with a particle size no larger than 0.075 mm) and a second component (with a particle size larger than 0.075 mm) are compounded in a mass ratio of 1:1-3, the dry-mix mortar possesses suitable friction during mechanized dry material delivery, ensuring smooth air delivery. Furthermore, during use, when wet materials are pumped via a screw pump with tubing, this ratio reduces friction during pumping, ensuring smooth operation of the screw pump and minimizing wear and tear, extending its service life. Based on this, the inventors developed this solution.

[0011] In order to achieve the above-mentioned object, the present invention provides, in a first aspect, a machine-sprayable dry-mix mortar composition, comprising a first component having a particle size of not more than 0.075 mm and a second component having a particle size of more than 0.075 mm;

[0012] The mass ratio of the first component to the second component is 1:1-3, and the content of the second component with a particle size of not less than 1.18 mm is 13-50 wt% based on the total mass of the second component;

[0013] The first component contains silicate cement and machine-made medium sand I, and optionally further contains component A1;

[0014] The second component contains machine-made medium sand II, and optionally also contains machine-made coarse sand and component A2;

[0015] The component A1 and the component A2 are each independently selected from at least one of stone powder and fly ash;

[0016] Based on the total mass of the composition, the content of the silicate cement is 13-20wt%, the content of the component A1 is 0-23wt%, the content of the sand I in the machine-made sand is 3-10wt%, the content of the component A2 is 0-9wt%, the content of the sand II in the machine-made sand is 50-76wt%, and the content of the coarse sand in the machine-made sand is 0-20wt%.

[0017] A second aspect of the present invention provides a method for preparing a machine-sprayable dry-mix mortar, the method comprising: first mixing cellulose ether, starch ether, an air-entraining agent and the composition described in the first aspect.

[0018] The third aspect of the present invention provides a machine-sprayable dry-mix mortar prepared by the method described in the second aspect.

[0019] The fourth aspect of the present invention provides a method for using the machine-sprayable dry-mixed mortar described in the third aspect, the method comprising: transporting the machine-sprayable dry-mixed mortar to a stirring device through an air delivery device for a second mixing with water to obtain wet mortar, and spraying the wet mortar to a material use point through a pumping device; the mass ratio of the machine-sprayable dry-mixed mortar to the water is 100:14-20.

[0020] The dry-mixed mortar prepared by the dry-mixed mortar composition provided by the present invention can be transported by air delivery equipment, and the air delivery stability is good, which effectively solves the problem of difficulty in carrying mortar upstairs; moreover, after the dry-mixed mortar provided by the present invention is made into wet mortar, it has excellent pumping performance, is not easy to segregate during the pumping process, and can achieve the purpose of continuous pumping. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a rendering of the formed surface obtained after the machine-sprayable dry-mix mortar provided in Example 1 of the present invention is sprayed on the wall. DETAILED DESCRIPTION

[0022] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0023] It should be noted that, in various aspects of the present invention, for the same components in various aspects, the present invention is only described once in one aspect without repeated description, which should not be understood by those skilled in the art as a limitation of the present invention.

[0024] In the present invention, unless otherwise specified, the room temperature or normal temperature refers to 25±2°C.

[0025] As mentioned above, the first aspect of the present invention provides a machine-sprayable dry-mix mortar composition comprising a first component having a particle size of no greater than 0.075 mm and a second component having a particle size greater than 0.075 mm;

[0026] The mass ratio of the first component to the second component is 1:1-3, and the content of the second component with a particle size of not less than 1.18 mm is 13-50 wt% based on the total mass of the second component;

[0027] The first component contains silicate cement and machine-made medium sand I, and optionally further contains component A1;

[0028] The second component contains machine-made medium sand II, and optionally also contains machine-made coarse sand and component A2;

[0029] The component A1 and the component A2 are each independently selected from at least one of stone powder and fly ash;

[0030] Based on the total mass of the composition, the content of the silicate cement is 13-20wt%, the content of the component A1 is 0-23wt%, the content of the sand I in the machine-made sand is 3-10wt%, the content of the component A2 is 0-9wt%, the content of the sand II in the machine-made sand is 50-76wt%, and the content of the coarse sand in the machine-made sand is 0-20wt%.

[0031] Preferably, in the dry-mixed mortar composition, the mass ratio of the first component to the second component is 1:1.5-3. During the research process, the inventors found that adopting the specific embodiment under this preferred embodiment can obtain a dry-mixed mortar with better air-transport stability.

[0032] Preferably, based on the total mass of the second component, the content of the second component having a particle size of not less than 1.18 mm is 13-42 wt %. During the research process, the inventors found that in the specific embodiment under this preferred embodiment, the wet mortar formed by the prepared dry-mixed mortar has better pumping performance.

[0033] Preferably, based on the total mass of the composition, the content of the silicate cement is 14-20wt%, the content of the component A1 is 0-9wt%, the content of the sand I in the machine-made sand is 3-9wt%, the content of the component A2 is 0-3wt%, the content of the sand II in the machine-made sand is 50-70wt%, and the content of the coarse sand in the machine-made sand is 5-10wt%.

[0034] It should be noted that component A1 and component A2 are of the same type, and the only difference between them is the particle size. Specifically, the particle size of component A1 is not greater than 0.075 mm, and the particle size of component A2 is greater than 0.075 mm.

[0035] It should be noted that, in actual application, the machine-made medium sand I and the machine-made medium sand II both belong to machine-made medium sand, and the difference between the two is the different particle size ranges. Specifically, the particle size of the machine-made medium sand I is not greater than 0.075 mm, and the particle size of the machine-made medium sand II is greater than 0.075 mm. Preferably, based on the total mass of the machine-made medium sand, the content of the machine-made medium sand with a particle size in the range of 0-0.075 mm is 5-15 wt%, and the content of the machine-made medium sand with a particle size in the range of 0.075-0.15 mm is 5-15 wt%. The content of sand in the machine-made sand within the range is 7-13wt%, the content of sand in the machine-made sand with a particle size in the range of 0.15mm-0.3mm is 10-15wt%, the content of sand in the machine-made sand with a particle size in the range of 0.3mm-0.6mm is 20-25wt%, the content of sand in the machine-made sand with a particle size in the range of 0.6mm-1.18mm is 25-35wt%, and the content of sand in the machine-made sand with a particle size in the range of 1.18mm-2.36mm is 10-20wt%.

[0036] Preferably, based on the total mass of the machine-made sand and coarse sand, the content of the machine-made sand and coarse sand with a particle size in the range of 0.6mm-1.18mm is 1-5wt%, the content of the machine-made sand and coarse sand with a particle size in the range of 1.18mm-2.36mm is 83-90wt%, and the content of the machine-made sand and coarse sand with a particle size in the range of 2.36mm-4.75mm is 7-15wt%.

[0037] According to a particularly preferred embodiment of the present invention, the Portland cement is P42.5 Portland cement.

[0038] As mentioned above, the second aspect of the present invention provides a method for preparing a sprayable dry-mix mortar, which comprises: first mixing cellulose ether, starch ether, an air-entraining agent and the composition described in the first aspect.

[0039] The present invention has no special requirements for the specific operation of the mixing and the order of adding the components during the mixing process. The mixing can be carried out by methods known in the art, or the cellulose ether, starch ether, air entraining agent and the components in the dry-mixed mortar composition can be mixed in any order of adding the components. The present invention will not go into details here, and those skilled in the art should not understand this as a limitation of the present invention.

[0040] Preferably, the mass ratio of the composition, the cellulose ether, the starch ether and the air-entraining agent is 1000: 0.3-0.6: 0.2-0.5: 0.1-0.3.

[0041] Preferably, the cellulose ether is selected from at least one of methyl hydroxyethyl cellulose ether, methyl hydroxypropyl cellulose ether, methyl cellulose ether, hydroxyethyl cellulose ether and ethyl hydroxyethyl cellulose ether.

[0042] According to a particularly preferred embodiment of the present invention, the cellulose ether is selected from at least one of LH40M, LK40M and LH20M purchased from Tianpu Company.

[0043] Preferably, the starch ether is at least one of hydroxyalkyl starch, cationic starch, anionic starch, hydroxypropyl starch phosphate, and hydroxypropyl glycerol distarch.

[0044] According to a particularly preferred embodiment of the present invention, the starch ether is selected from at least one of CASUOL301 and OPAGEL FP6 purchased from Avibe.

[0045] Preferably, the air entraining agent is selected from at least one of rosin resins, alkyl sulfonates, alkyl aromatic sulfonates, fatty alcohol sulfonates, soaps, and nonionic surfactants.

[0046] According to a particularly preferred embodiment of the present invention, the air entraining agent is selected from at least one of AE1420 purchased from Solvay, K12 purchased from Guangzhou Jiantubao Company, and OSB purchased from Clariant.

[0047] As mentioned above, the third aspect of the present invention provides a machine-sprayable dry-mix mortar prepared by the method described in the second aspect.

[0048] As mentioned above, the fourth aspect of the present invention provides a method for using the machine-sprayable dry-mixed mortar described in the third aspect, the method comprising: transporting the machine-sprayable dry-mixed mortar to a stirring device through an air delivery device for a second mixing with water to obtain wet mortar, and spraying the wet mortar to a material use point through a pumping device; the mass ratio of the machine-sprayable dry-mixed mortar to the water is 100:14-20.

[0049] It should be noted that in the actual construction process, the air delivery device is first connected to the silo containing the machine-sprayable dry-mixed mortar. According to the characteristics of the machine-sprayable dry-mixed mortar that can be air-delivered, the machine-sprayable dry-mixed mortar is air-delivered to the mixing device through the air delivery device, and then the wet mortar is transported to the pumping device through the stirring device, and finally the pumping device is used to spray it on the wall.

[0050] The present invention has no special requirements on the types of the air delivery device, the stirring device and the pumping device. The air delivery device, stirring device and pumping device known in the art can be used. It only needs to be able to make the machine-sprayable dry-mixed mortar into wet mortar and transport it to the material use point. The present invention will not go into details here, and those skilled in the art should not understand it as a limitation of the present invention.

[0051] According to a particularly preferred embodiment of the present invention, the pneumatic conveying device is met-c G140.

[0052] Preferably, the stirring device is selected from any one of met-c D30 and domix 2000.

[0053] According to a particularly preferred embodiment of the present invention, the pumping device is met-c P50.

[0054] The present invention will be described in detail below by way of examples. In the following examples, unless otherwise stated, the raw materials and instruments involved are all commercially available products.

[0055] Portland cement: P42.5 grade Portland cement, purchased from Southern Cement Company;

[0056] Component A1: stone powder, particle size range 0-0.075mm, from Zhonglian New Materials Technology Co., Ltd.

[0057] Component A2: stone powder, particle size range 0.075-0.6mm, from Zhonglian New Materials Technology Co., Ltd.

[0058] In the following examples, medium sand I and medium sand II are both manufactured medium sands from Zhonglian New Materials Technology Co., Ltd. Specifically, the particle size of medium sand I is in the range of 0-0.075 mm, and the particle size of medium sand II is in the range of 0.075-2.36 mm.

[0059] In the following examples, the machine-made coarse sand is sourced from Zhonglian New Materials Technology Co., Ltd.

[0060] Cellulose ether I: LH40M, purchased from Tianpu Company;

[0061] Cellulose ether II: LK40M, purchased from Tianpu Company;

[0062] Cellulose ether III: LH20M, purchased from Tianpu Company;

[0063] Starch ether I: CASUOL 301, purchased from Avibe;

[0064] Starch ether II: OPAGEL FP6, purchased from Avibe;

[0065] Air entraining agent I: AE1420, purchased from Solvay;

[0066] Air entraining agent II: K12, purchased from Guangzhou Jiantubao Company;

[0067] Air entraining agent III: OSB, purchased from Clariant.

[0068] Pneumatic conveying device: met-c G140, from Zhonglian New Materials Technology Co., Ltd.

[0069] Stirring device: met-c D30, from Zhonglian New Materials Technology Co., Ltd.

[0070] Pumping device: met-c P50, from Zhonglian New Materials Technology Co., Ltd.

[0071] In the following examples, unless otherwise specified, the amounts of the components in the compositions involved in the following examples are expressed as percentages by mass. Taking the percentage by mass of the Portland cement in Example 1 as an example, the calculation method is: percentage by mass of Portland cement = (mass of Portland cement) / (sum of the masses of the components in Example 1) × 100%.

[0072] In the following examples, the total mass of the composition is 1 t.

[0073] Example 1

[0074] This embodiment provides a method for preparing a sprayable dry-mix mortar, comprising:

[0075] 20 wt% of Portland cement, 3.75 wt% of component A1, 1.25 wt% of component A2, 6.5 wt% of machine-made medium sand I, 58.5 wt% of machine-made medium sand II, and 10 wt% of machine-made coarse sand are uniformly mixed to obtain a first mixture; in the first mixture, the mass ratio of the first component having a particle size of no greater than 0.075 mm to the second component having a particle size of greater than 0.075 mm is approximately 1:2.31, and the content of the second component having a particle size of no less than 1.18 mm is approximately 28.2 wt% based on the total mass of the second component;

[0076] Wherein, based on the total mass of the sand in the machine-made sand, the content of sand in the machine-made sand with a particle size within the range of 0-0.075 mm is 10 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.075-0.15 mm is 8 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.15 mm-0.3 mm is 12 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.3 mm-0.6 mm is 25 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.6 mm-1.18 mm is 30 wt%, and the content of sand in the machine-made sand with a particle size within the range of 1.18 mm-2.36 mm is 15 wt%;

[0077] Based on the total mass of the machine-made coarse sand, the content of the machine-made coarse sand with a particle size in the range of 0.6 mm to 1.18 mm is 1 wt %, the content of the machine-made coarse sand with a particle size in the range of 1.18 mm to 2.36 mm is 85 wt %, and the content of the machine-made coarse sand with a particle size in the range of 2.36 mm to 4.75 mm is 14 wt %;

[0078] Then, the first mixture prepared above was mixed with 0.5 kg of cellulose ether I, 0.2 kg of starch ether I, and 0.2 kg of air-entraining agent I (stirring speed was 120 rpm, time was 2 min) to obtain a sprayable dry-mix mortar S1.

[0079] The method for using the machine-sprayable dry-mixed mortar in this embodiment is as follows: the machine-sprayable dry-mixed mortar prepared above is transported to the stirring device met-c D30 through the air conveying device met-c G140 for a second mixing with water (stirring speed of 280 rpm, temperature of room temperature, theoretical stirring capacity of 30 L / min) to obtain wet mortar, and finally the wet mortar is sprayed onto the wall through the pumping device met-c P50; wherein the mass ratio of the machine-sprayable dry-mixed mortar to water is 100:16.

[0080] Example 2

[0081] This embodiment provides a method for preparing a sprayable dry-mix mortar, comprising:

[0082] 20 wt% of Portland cement, 5.6 wt% of machine-made medium sand I, 64.4 wt% of machine-made medium sand II, and 10 wt% of machine-made coarse sand are uniformly mixed to obtain a first mixture; in the first mixture, the mass ratio of the first component having a particle size of not greater than 0.075 mm to the second component having a particle size of greater than 0.075 mm is approximately 1:2.91, and the content of the second component having a particle size of not less than 1.18 mm is 22.7 wt% based on the total mass of the second component;

[0083] Wherein, based on the total mass of the sand in the machine-made sand, the content of sand in the machine-made sand with a particle size within the range of 0-0.075 mm is 8 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.075-0.15 mm is 13 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.15 mm-0.3 mm is 15 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.3 mm-0.6 mm is 25 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.6 mm-1.18 mm is 29 wt%, and the content of sand in the machine-made sand with a particle size within the range of 1.18 mm-2.36 mm is 10 wt%;

[0084] Based on the total mass of the machine-made coarse sand, the content of the machine-made coarse sand with a particle size in the range of 0.6 mm to 1.18 mm is 1 wt %, the content of the machine-made coarse sand with a particle size in the range of 1.18 mm to 2.36 mm is 90 wt %, and the content of the machine-made coarse sand with a particle size in the range of 2.36 mm to 4.75 mm is 9 wt %;

[0085] Then, the first mixture prepared above, 0.5 kg of cellulose ether II, 0.2 kg of starch ether II, 0.2 kg of air entraining agent II and the first mixture material were mixed for the first time (stirring speed was 120 rpm, time was 2 min) to obtain a sprayable dry-mix mortar S2.

[0086] The method of using the machine-sprayable dry-mixed mortar in this embodiment refers to the method of use in Example 1, except that the mass ratio of the machine-sprayable dry-mixed mortar to water is 100:15.

[0087] Example 3

[0088] This embodiment provides a method for preparing a sprayable dry-mix mortar, comprising:

[0089] 20 wt% of Portland cement, 7.5 wt% of component A1, 2.5 wt% of component A2, 9 wt% of machine-made medium sand I, 51 wt% of machine-made medium sand II, and 10 wt% of machine-made coarse sand are uniformly mixed to obtain a first mixture; in the first mixture, the mass ratio of the first component with a particle size of no greater than 0.075 mm to the second component with a particle size of greater than 0.075 mm is approximately 1:1.74, and the content of the second component with a particle size of no less than 1.18 mm is 34.5 wt% based on the total mass of the second component;

[0090] Wherein, based on the total mass of the sand in the machine-made sand, the content of sand in the machine-made sand with a particle size within the range of 0-0.075 mm is 15 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.075-0.15 mm is 7 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.15 mm-0.3 mm is 13 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.3 mm-0.6 mm is 20 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.6 mm-1.18 mm is 25 wt%, and the content of sand in the machine-made sand with a particle size within the range of 1.18 mm-2.36 mm is 20 wt%;

[0091] Based on the total mass of the machine-made coarse sand, the content of the machine-made coarse sand with a particle size in the range of 0.6 mm to 1.18 mm is 1 wt %, the content of the machine-made coarse sand with a particle size in the range of 1.18 mm to 2.36 mm is 84 wt %, and the content of the machine-made coarse sand with a particle size in the range of 2.36 mm to 4.75 mm is 15 wt %;

[0092] Then, the first mixture prepared above, 0.5 kg of cellulose ether III, 0.3 kg of starch ether II, 0.2 kg of air entraining agent III and the first mixture material were mixed for the first time (stirring speed was 120 rpm, time was 2 min) to obtain a sprayable dry-mix mortar S3.

[0093] The method of using the machine-sprayable dry-mixed mortar in this embodiment refers to the method of use in Example 1, except that the mass ratio of the machine-sprayable dry-mixed mortar to water is 100:17.5.

[0094] Example 4

[0095] This embodiment provides a method for preparing a sprayable dry-mix mortar, comprising:

[0096] 20 wt% of Portland cement, 7.5 wt% of machine-made medium sand I, 67.5 wt% of machine-made medium sand II, and 5 wt% of machine-made coarse sand are uniformly mixed to obtain a first mixture; in the first mixture, the mass ratio of the first component with a particle size of no greater than 0.075 mm to the second component with a particle size of greater than 0.075 mm is approximately 1:2.64, and the content of the second component with a particle size of no less than 1.18 mm is approximately 16.6 wt% based on the total mass of the second component;

[0097] Wherein, based on the total mass of the sand in the machine-made sand, the content of the sand in the machine-made sand with a particle size within the range of 0-0.075 mm is 10 wt%, the content of the sand in the machine-made sand with a particle size within the range of 0.075-0.15 mm is 10 wt%, the content of the sand in the machine-made sand with a particle size within the range of 0.15 mm-0.3 mm is 15 wt%, the content of the sand in the machine-made sand with a particle size within the range of 0.3 mm-0.6 mm is 25 wt%, the content of the sand in the machine-made sand with a particle size within the range of 0.6 mm-1.18 mm is 30 wt%, and the content of the sand in the machine-made sand with a particle size within the range of 1.18 mm-2.36 mm is 10 wt%;

[0098] Based on the total mass of the machine-made coarse sand, the content of the machine-made coarse sand with a particle size in the range of 0.6 mm to 1.18 mm is 5 wt %, the content of the machine-made coarse sand with a particle size in the range of 1.18 mm to 2.36 mm is 83 wt %, and the content of the machine-made coarse sand with a particle size in the range of 2.36 mm to 4.75 mm is 7 wt %;

[0099] Then, the first mixture prepared above was mixed with 0.5 kg of cellulose ether, 0.2 kg of starch ether, and 0.2 kg of air entraining agent (stirring speed was 120 rpm, time was 3 min) to obtain a sprayable dry-mix mortar S4.

[0100] The remaining steps are the same as those in Example 1 to obtain the sprayable dry-mix mortar S4.

[0101] The method of using the machine-sprayable dry-mix mortar in this embodiment is the same as that in Example 1.

[0102] Example 5

[0103] This embodiment provides a method for preparing a sprayable dry-mix mortar, comprising:

[0104] 14 wt% of Portland cement, 8.25 wt% of component A1, 2.75 wt% of component A2, 6.5 wt% of machine-made medium sand I, 58.5 wt% of machine-made medium sand II, and 10 wt% of machine-made coarse sand are uniformly mixed to obtain a first mixture; in the first mixture, the mass ratio of the first component with a particle size of no greater than 0.075 mm to the second component with a particle size of greater than 0.075 mm is approximately 1:2.47, and the content of the second component with a particle size of no less than 1.18 mm is approximately 21.8 wt% based on the total mass of the second component;

[0105] Wherein, based on the total mass of the sand in the machine-made sand, the content of sand in the machine-made sand with a particle size within the range of 0-0.075 mm is 10 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.075-0.15 mm is 12 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.15 mm-0.3 mm is 14 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.3 mm-0.6 mm is 24 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.6 mm-1.18 mm is 30 wt%, and the content of sand in the machine-made sand with a particle size within the range of 1.18 mm-2.36 mm is 10 wt%;

[0106] Based on the total mass of the machine-made coarse sand, the content of the machine-made coarse sand with a particle size in the range of 0.6 mm to 1.18 mm is 4 wt %, the content of the machine-made coarse sand with a particle size in the range of 1.18 mm to 2.36 mm is 88 wt %, and the content of the machine-made coarse sand with a particle size in the range of 2.36 mm to 4.75 mm is 8 wt %;

[0107] Then, the first mixture prepared above was mixed with 0.5 kg of cellulose ether, 0.2 kg of starch ether, and 0.2 kg of air entraining agent (stirring speed was 120 rpm, time was 1 min) to obtain a sprayable dry-mix mortar S5.

[0108] The remaining steps are the same as those in Example 1 to obtain the sprayable dry-mix mortar S5.

[0109] The method of using the machine-sprayable dry-mix mortar in this embodiment is the same as that in Example 1.

[0110] Example 6

[0111] A sprayable dry-mix mortar was prepared according to the method of Example 1, except that 20 wt% of Portland cement, 22.5 wt% of component A1, 7.5 wt% of component A2, 7.5 wt% of machine-made medium sand I, and 42.5 wt% of machine-made medium sand II were uniformly mixed to obtain a first mixture;

[0112] So that in the first mixture, the mass ratio of the first component with a particle size not greater than 0.075 mm and the second component with a particle size greater than 0.075 mm is 1:1, and based on the total mass of the second component, the content of the second component with a particle size not less than 1.18 mm is 15 wt%.

[0113] Wherein, based on the total mass of the sand in the machine-made sand, the content of sand in the machine-made sand with a particle size within the range of 0-0.075 mm is 15 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.075-0.15 mm is 8 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.15 mm-0.3 mm is 13 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.3 mm-0.6 mm is 21 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.6 mm-1.18 mm is 28 wt%, and the content of sand in the machine-made sand with a particle size within the range of 1.18 mm-2.36 mm is 15 wt%;

[0114] The remaining steps are the same as those in Example 1 to obtain the sprayable dry-mix mortar S6.

[0115] The method of using the machine-sprayable dry-mix mortar in this embodiment is the same as that in Example 1.

[0116] Example 7

[0117] A sprayable dry-mix mortar was prepared according to the method of Example 1, except that 20 wt% of Portland cement, 3.75 wt% of component A1, 1.25 wt% of component A2, 8.25 wt% of machine-made medium sand I, 46.75 wt% of machine-made medium sand II, and 20 wt% of machine-made coarse sand were uniformly mixed to obtain a first mixture;

[0118] So that in the first mixture, the mass ratio of the first component with a particle size not greater than 0.075 mm and the second component with a particle size greater than 0.075 mm is approximately 1:2.1, and based on the total mass of the second component, the content of the second component with a particle size not less than 1.18 mm is 45.3 wt%.

[0119] Wherein, based on the total mass of the sand in the machine-made sand, the content of the sand in the machine-made sand with a particle size within the range of 0-0.075 mm is 15 wt%, the content of the sand in the machine-made sand with a particle size within the range of 0.075-0.15 mm is 10 wt%, the content of the sand in the machine-made sand with a particle size within the range of 0.15 mm-0.3 mm is 10 wt%, the content of the sand in the machine-made sand with a particle size within the range of 0.3 mm-0.6 mm is 20 wt%, the content of the sand in the machine-made sand with a particle size within the range of 0.6 mm-1.18 mm is 25 wt%, and the content of the sand in the machine-made sand with a particle size within the range of 1.18 mm-2.36 mm is 20 wt%;

[0120] Based on the total mass of the machine-made coarse sand, the content of the machine-made coarse sand with a particle size in the range of 0.6 mm to 1.18 mm is 1 wt %, the content of the machine-made coarse sand with a particle size in the range of 1.18 mm to 2.36 mm is 89 wt %, and the content of the machine-made coarse sand with a particle size in the range of 2.36 mm to 4.75 mm is 10 wt %;

[0121] The remaining steps are the same as in Example 1 to obtain the sprayable dry-mix mortar S7.

[0122] The method of using the machine-sprayable dry-mix mortar in this embodiment is the same as that in Example 1.

[0123] Comparative Example 1

[0124] A sprayable dry-mix mortar was prepared according to the method of Example 1, except that 20 wt% of Portland cement, 7.5 wt% of machine-made medium sand I, 42.5 wt% of machine-made medium sand II, and 30 wt% of machine-made coarse sand were uniformly mixed to obtain a first mixture;

[0125] So that in the first mixture, the mass ratio of the first component with a particle size not greater than 0.075 mm and the second component with a particle size greater than 0.075 mm is approximately 1:2.64, and based on the total mass of the second component, the content of the second component with a particle size not less than 1.18 mm is approximately 54.8 wt%.

[0126] Wherein, based on the total mass of the sand in the machine-made sand, the content of sand in the machine-made sand with a particle size within the range of 0-0.075 mm is 15 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.075-0.15 mm is 7 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.15 mm-0.3 mm is 10 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.3 mm-0.6 mm is 22 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.6 mm-1.18 mm is 26 wt%, and the content of sand in the machine-made sand with a particle size within the range of 1.18 mm-2.36 mm is 20 wt%;

[0127] Based on the total mass of the machine-made coarse sand, the content of the machine-made coarse sand with a particle size in the range of 0.6 mm to 1.18 mm is 1 wt %, the content of the machine-made coarse sand with a particle size in the range of 1.18 mm to 2.36 mm is 85 wt %, and the content of the machine-made coarse sand with a particle size in the range of 2.36 mm to 4.75 mm is 14 wt %;

[0128] The remaining steps are the same as in Example 2 to obtain the sprayable dry-mix mortar DS1.

[0129] The method of using the machine-sprayable dry-mix mortar in this embodiment is the same as that in Example 2.

[0130] Comparative Example 2

[0131] A sprayable dry-mix mortar was prepared according to the method of Example 2, except that 20 wt% of Portland cement, 3.5 wt% of machine-made medium sand I, 66.5 wt% of machine-made medium sand II, and 10 wt% of machine-made coarse sand were uniformly mixed to obtain a first mixture;

[0132] So that in the first mixture, the mass ratio of the first component with a particle size not greater than 0.075 mm and the second component with a particle size greater than 0.075 mm is approximately 1:3.26, and based on the total mass of the second component, the content of the second component with a particle size not less than 1.18 mm is approximately 20.9 wt%.

[0133] Wherein, based on the total mass of the sand in the machine-made sand, the content of sand in the machine-made sand with a particle size within the range of 0-0.075 mm is 5 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.075-0.15 mm is 13 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.15 mm-0.3 mm is 15 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.3 mm-0.6 mm is 25 wt%, the content of sand in the machine-made sand with a particle size within the range of 0.6 mm-1.18 mm is 32 wt%, and the content of sand in the machine-made sand with a particle size within the range of 1.18 mm-2.36 mm is 10 wt%;

[0134] Based on the total mass of the machine-made coarse sand, the content of the machine-made coarse sand with a particle size in the range of 0.6 mm to 1.18 mm is 5 wt %, the content of the machine-made coarse sand with a particle size in the range of 1.18 mm to 2.36 mm is 85 wt %, and the content of the machine-made coarse sand with a particle size in the range of 2.36 mm to 4.75 mm is 10 wt %;

[0135] The remaining steps are the same as in Example 2 to obtain the sprayable dry-mix mortar DS2.

[0136] The method of using the machine-sprayable dry-mix mortar in this embodiment is the same as that in Example 2.

[0137] Test Example 1

[0138] The dry-mixed mortar prepared in the embodiment and the comparative example was subjected to an air delivery experiment. The dry-mixed mortar was air-delivered to the stirring device through an air delivery pipe. Each air delivery pipe was 12 m long. The air delivery state was observed. The specific results are shown in Table 1.

[0139] Table 1

[0140] Example No. Air delivery status Example 1 Set up 3 air delivery pipes to ensure smooth air delivery Example 2 Set up 3 air delivery pipes to ensure smooth air delivery Example 3 Set up 3 air delivery pipes to ensure smooth air delivery Example 4 Set up 3 air delivery pipes to ensure smooth air delivery Example 5 Set up 3 air delivery pipes to ensure smooth air delivery Example 6 Set up 3 air delivery pipes to ensure smooth air delivery Example 7 Set up 3 air delivery pipes to ensure smooth air delivery Comparative Example 1 Set up 2 air delivery pipes, and air delivery to the second blocked pipe Comparative Example 2 Set up 1 air delivery pipe, air delivery pipe blocked

[0141] It can be seen from the results in the above table that the dry-mixed mortar prepared by the dry-mixed mortar composition provided by the present invention can be transported by air conveying equipment, and the air conveying stability is good. There is no air conveying pipe blockage phenomenon when the air conveying distance reaches 36m.

[0142] Test Example 2

[0143] A pumping experiment was conducted on wet mortar prepared by using the dry-mixed mortar prepared in the embodiment and the comparative example. A pumping pipe with a diameter of 35 mm and a pumping pipe with a diameter of 25 mm were connected to the pumping device in sequence to observe the pumping state. The specific results are shown in Table 2.

[0144] Table 2

[0145] Example No. Pumping status Pump pressure, bar Example 1 Pumping is smooth and without abnormalities 25 Example 2 Pumping is smooth and without abnormalities 28 Example 3 Pumping is smooth and without abnormalities 23 Example 4 Pumping is smooth and without abnormalities 15 Example 5 Pumping is smooth and without abnormalities 18 Example 6 Pumping is smooth and without abnormalities 10 Example 7 Pumping is smooth and without abnormalities 40 Comparative Example 1 Pumping pipe blockage - Comparative Example 2 Pumping pipe blockage -

[0146] It can be seen from the results in the above table that the wet mortar prepared by the dry-mixed mortar composition provided by the present invention has excellent pumping performance, is not easy to segregate during the pumping process, and can achieve the purpose of continuous pumping.

[0147] By comparing Example 1 and Example 6, it can be seen that the mortar obtained in Example 6 of the present invention has a higher viscosity after being sprayed on the wall, and it is more laborious to finish the surface.

[0148] By comparing Example 1 and Example 7, it can be seen that the mortar obtained in Example 7 of the present invention has a high pump pressure during pumping, which causes greater wear on the equipment.

[0149] The present invention exemplarily provides a molding surface effect diagram obtained after the machine-sprayable dry-mixed mortar S1 provided in Example 1 of the present invention is sprayed on the wall, see Figure 1 .

[0150] from Figure 1 It can be seen from the figure that after the wet mortar is applied to the wall, it is easy to scrape and finish, and there is basically no hollowing or cracking on the formed surface.

[0151] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A machine sprayable dry-mix mortar composition, characterized in that: The composition comprises a first component having a particle size of no greater than 0.075 mm and a second component having a particle size greater than 0.075 mm; The mass ratio of the first component to the second component is 1:1.5-3, and based on the total mass of the second component, the content of the second component with a particle size of not less than 1.18 mm is 13-50wt%; The first component contains silicate cement, machine-made medium sand I and component A1; The second component contains machine-made medium sand II, machine-made coarse sand and component A2; The component A1 and the component A2 are each independently selected from at least one of stone powder and fly ash; Based on the total mass of the composition, the content of the silicate cement is 14-20wt%, the content of the component A1 is 3.75-9wt%, the content of the medium sand I in the machine-made sand is 3-9wt%, the content of the component A2 is 1.25-3wt%, the content of the medium sand II in the machine-made sand is 50-70wt%, and the content of the coarse sand in the machine-made sand is 5-10wt%. Based on the total mass of the machine-made sand and coarse sand, the content of the machine-made sand and coarse sand with a particle size in the range of 0.6mm-1.18mm is 1-5wt%, the content of the machine-made sand and coarse sand with a particle size in the range of 1.18mm-2.36mm is 83-90wt%, and the content of the machine-made sand and coarse sand with a particle size in the range of 2.36mm-4.75mm is 7-15wt%.

2. The composition according to claim 1, wherein Based on the total mass of the second component, the content of the second component having a particle size of not less than 1.18 mm is 13-42 wt %.

3. A method for preparing a sprayable dry-mix mortar, characterized in that: The method comprises: first mixing cellulose ether, starch ether, an air entraining agent and the composition according to claim 1 or 2.

4. The method according to claim 3, wherein: The mass ratio of the composition, the cellulose ether, the starch ether and the air-entraining agent is 1000: 0.3-0.6: 0.2-0.5: 0.1-0.

3.

5. The method according to claim 3 or 4, wherein: The cellulose ether is selected from at least one of methyl hydroxyethyl cellulose ether, methyl hydroxypropyl cellulose ether, methyl cellulose ether, hydroxyethyl cellulose ether and ethyl hydroxyethyl cellulose ether; and / or The starch ether is selected from at least one of hydroxyalkyl starch, cationic starch, anionic starch, hydroxypropyl starch phosphate, and hydroxypropyl glycerol distarch; and / or The air entraining agent is selected from at least one of rosin resins, alkyl sulfonates, alkyl aromatic hydrocarbon sulfonates, fatty alcohol sulfonates, soaps, and non-ionic surfactants.

6. A machine-sprayable dry-mix mortar prepared by the method according to any one of claims 3 to 5.

7. A method for using the machine-sprayable dry-mix mortar according to claim 6, characterized in that: The method includes: conveying the machine-sprayable dry-mixed mortar to a stirring device through an air conveying device, performing a second mixing with water to obtain wet mortar, and spraying the wet mortar to a material use point through a pumping device; the mass ratio of the machine-sprayable dry-mixed mortar to water is 100:14-20.

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