Waste concrete reclaimed sand self-leveling mortar and mix proportion design method thereof

Abstract

The invention discloses waste concrete reclaimed sand self-leveling mortar which is mainly prepared from cement paste and reclaimed sand, the cement paste is composed of cement, reclaimed micro powder, an additive and water, and the invention further discloses a mix proportion design method of the waste concrete reclaimed sand self-leveling mortar. According to the invention, the working performance of the cement paste in the reclaimed sand self-leveling mortar is regulated and controlled, so that the cement, the reclaimed micro powder and other powder raw materials in the mortar present a certain rule, the waste concrete reclaimed sand is fully utilized, and when the mix proportion of the reclaimed sand self-leveling mortar is designed, the mixing ratio of the reclaimed sand self-leveling mortar is greatly improved. The working performance, the mechanical performance, other performance and the like of the reclaimed sand self-leveling mortar can be considered, the use amount of the reclaimed sand and the reclaimed micro powder is further increased to the maximum extent, and the use amount of a cementing material in cement paste is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of building materials, and particularly relates to a self-leveling mortar made of recycled sand from waste concrete and a mix ratio design method thereof. Background Art

[0002] The amount of construction solid waste in my country is increasing year by year, and its disposal is mainly done by dumping and filling, which occupies a large amount of land. At the same time, my country's natural sand and gravel and mineral admixture resources are very scarce, and there is an urgent need to strengthen the resource utilization of construction solid waste and use scientific research to improve the level of resource utilization.

[0003] The waste concrete is crushed, ground, and sorted to produce regenerated sand, which is then used to replace natural sand in mortar and concrete. The present invention conducts relevant research to address the problems of complex sources, high water absorption, and low activity of waste concrete regenerated sand, and develops a self-leveling mortar made of waste concrete regenerated sand and a mix ratio design method thereof, providing a new way for the recycling of waste concrete resources. Summary of the invention

[0004] The present invention aims to provide a self-leveling mortar made of recycled sand from waste concrete, which uses recycled sand and recycled micro-powder to replace natural sand and regenerate waste concrete and the like as resources.

[0005] The purpose of the present invention is also to provide a mix ratio design method for the above-mentioned waste concrete recycled sand self-leveling mortar. Through reasonable design, this method can take into account the working performance and mechanical properties of the mortar, maximize the amount of recycled sand and recycled micropowder, and reduce the amount of cementitious material in cement paste.

[0006] The above-mentioned first purpose of the present invention can be achieved by the following technical scheme: a self-leveling mortar of waste concrete recycled sand, the self-leveling mortar is mainly prepared by cement paste and recycled sand, the cement paste is composed of cement, recycled micropowder, admixture and water, and the mass ratio of each component in each cubic meter of self-leveling mortar is as follows: 340-500kg of cement, 130-210kg of recycled micropowder, 30-50kg of admixture, 320-340kg of water, and 1080-1130kg of recycled sand.

[0007] Furthermore, the mass ratio of each component in each cubic meter of self-leveling mortar is as follows: 400-480 kg of cement, 150-206 kg of recycled micropowder, 40-48 kg of admixture, 325-335 kg of water, and 1090-1125 kg of recycled sand.

[0008] Preferably, the cement is silicate cement or ordinary silicate cement and has a strength grade of 42.5.

[0009] Preferably, the particle size of the regenerated micro powder is no greater than 75 μm, and the activity index is greater than 70%.

[0010] Preferably, the regenerated micro powder is derived from particles with a particle size not greater than 75 μm screened out from regenerated sand.

[0011] Preferably, the admixture is a water reducing agent.

[0012] Preferably, the water reducer is a common commercial product, such as a polycarboxylate water reducer.

[0013] Preferably, the regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand, the fineness modulus of the regenerated sand is 2.3-3.0, and the content of particles with a diameter less than 75 μm is 0.

[0014] The waste concrete regenerated sand self-leveling mortar in the present invention can be considered to be mainly composed of cement paste and regenerated sand, and its self-leveling properties are determined by the working performance of the cement paste and the properties of the regenerated sand, wherein the components of the cement paste are cement, regenerated micropowder, admixture and water.

[0015] The second object of the present invention can be achieved by the following technical solution: The mix ratio design method of the above-mentioned waste concrete recycled sand self-leveling mortar comprises the following steps:

[0016] (1) According to JGJ / T 98, cement paste is prepared using cement, recycled micro powder, admixture and water. The quality of cement, recycled micro powder, admixture and water required when the fluidity of cement paste is 200-250 mm is tested by orthogonal test;

[0017] (2) Regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The proportion of regenerated sand in the mixed sand is set to a. i And the shape coefficient b of the regenerated sand 再生砂 , and calculate the stacking porosity P of regenerated sand according to JGJ 52 再生砂 ;

[0018] (3) Select regenerated sand with a fineness modulus of 2.3 to 3.0 and a particle size of less than 75 μm and a content of 0. According to the sieve residue of each sieve in the regenerated sand screening, calculate Where S i is the specific surface area of ​​each level of regenerated sand, K i Refers to the percentage of sand on each sieve, N i refers to the amount of sand on each level of sand, R is the average particle size of each level of sieve, ρ 堆积 and ρ 表观 Obtained according to standard JGJ 52;

[0019] (4) Set the thickness H of the cement paste wrapped on the surface of the self-leveling mortar净浆 ;

[0020] (5) The cubic stacking model of regenerated sand is used to design the mortar mix ratio. The volume of regenerated sand is set as V 再生砂 , according to the packing porosity P of the regenerated sand 再生砂 , shape coefficient b of regenerated sand 再生砂 , the proportion of regenerated sand in mixed sand a i , the thickness of cement paste wrapped on the surface of self-leveling mortar H 净浆 as well as Calculate V 再生砂 , V 再生砂 The calculation formula is as follows:

[0021]

[0022] (6) According to the volume V of the regenerated sand 再生砂 The mass of the regenerated sand is calculated based on the apparent density ρapparent, and then combined with step (1), the mass ratio of each component of cement, regenerated micro powder, admixture, water and regenerated sand in each cubic meter of self-leveling mortar is obtained.

[0023] In the above-mentioned waste concrete recycled sand self-leveling mortar mix design method:

[0024] Preferably, in step (2), the proportion of regenerated sand in the mixed sand is i It is 0.7~1.

[0025] Preferably, the shape coefficient b of the regenerated sand in step (2) is 1.5 to 2.0.

[0026] Preferably, in step (4), the thickness H of the cement paste wrapped on the surface of the self-leveling mortar is set to 净浆 50~55μm.

[0027] The present invention has the following advantages: the present invention regulates the working performance of cement paste in the regenerated sand self-leveling mortar, so that the cement, regenerated micropowder and other powder raw materials in the mortar present a certain regularity, thereby making full use of the waste concrete regenerated sand, so that when designing the mix ratio of the regenerated sand self-leveling mortar, the working performance, mechanical properties and other properties of the regenerated sand self-leveling mortar can be taken into account, thereby maximizing the amount of regenerated sand and regenerated micropowder and reducing the amount of cementitious material in the cement paste. DETAILED DESCRIPTION

[0028] The present invention is further described below in conjunction with specific examples. The following examples are only for illustrative purposes and are not to be construed as limiting the present invention. Unless otherwise specified, the raw materials used in the following examples are conventional commercially available or commercially available raw materials, and unless otherwise specified, the methods and equipment used in the following examples are conventional methods and equipment used in the art.

[0029] The present invention is further described below in conjunction with specific examples. It should be understood that the following examples are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0030] Example 1

[0031] The waste concrete recycled sand self-leveling mortar provided in this embodiment is mainly composed of cement paste and recycled sand. The cement paste consists of cement, recycled micropowder, admixture and water. The mass ratio of each component in each cubic meter of self-leveling mortar is as follows: 430 kg of cement, 330 kg of water, 150 kg of recycled micropowder, 1125 kg of recycled sand and 43 kg of water reducer.

[0032] The cement is silicate cement and has a strength grade of 42.5.

[0033] The particle size of the regenerated micro powder is no more than 75 μm, and the activity index is greater than 70%.

[0034] The regenerated micro powder comes from particles with a particle size of no more than 75 μm screened out from the regenerated sand.

[0035] The regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The fineness modulus of the regenerated sand is 2.3-3.0, and the content of particles with a diameter less than 75 μm is 0.

[0036] The method for designing the mix ratio of the self-leveling mortar made of recycled sand from waste concrete in this embodiment comprises the following steps:

[0037] (1) According to JGJ / T 98, cement paste is prepared using cement, recycled micro powder, admixture and water. The mass of cement, recycled micro powder, admixture and water required per cubic meter of cement paste is tested by orthogonal test when the fluidity of cement paste is 200-250 mm;

[0038] (2) Regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The proportion of regenerated sand in the mixed sand is i =1, that is, all is regenerated sand, set the shape coefficient b of the regenerated sand 再生砂 is 1.65, and the stacking porosity P of regenerated sand is calculated according to JGJ 52 再生砂 is 0.425;

[0039] (3) Select regenerated sand with a fineness modulus of 2.8 and a particle size of less than 75 μm and a content of 0. According to the sieve residue of each sieve in the regenerated sand screening, calculate 4353.3m 2 / m 3 According to standard JGJ52, the apparent density of regenerated sand is 2400kg / m 3 , the bulk density of regenerated sand is 1380kg / m 3 ;

[0040] (4) Set the thickness H of the cement paste wrapped on the surface of the self-leveling mortar 净浆 =55μm;

[0041] (5) The cubic stacking model of regenerated sand (assuming 1 cubic meter) is used to design the mortar mix ratio. The volume of regenerated sand is set as V 再生砂 , according to the packing porosity P of the regenerated sand 再生砂 , shape coefficient b of regenerated sand 再生砂 , the proportion of regenerated sand in mixed sand a i , the thickness of cement paste wrapped on the surface of self-leveling mortar H 净浆 as well as Calculate V 再生砂 , V 再生砂 The calculation formula is as follows:

[0042]

[0043] The calculated V 再生砂 0.469m 3 ;

[0044] (6) According to the volume V of the regenerated sand 再生砂 The mass of the regenerated sand is calculated based on the apparent density ρapparent, and then combined with step (1), the mass ratio of each component of cement, regenerated micro powder, admixture, water and regenerated sand in each cubic meter of self-leveling mortar is obtained.

[0045] The specific results are as follows: self-leveling mortar is prepared by using recycled sand with a fineness modulus of 2.8, and the apparent density of the recycled sand is 2400kg / m 3 , the bulk density of regenerated sand is 1380kg / m 3 In each cubic meter of M30 strength grade cement mortar, there are 430kg of cement, 330kg of water, 150kg of recycled micropowder, 1125kg of recycled sand, and 43kg of water reducer. The fluidity of the mortar is 350mm and the measured compressive strength is 34.6MPa.

[0046] Example 2

[0047] The waste concrete recycled sand self-leveling mortar provided in this embodiment is mainly composed of cement paste and recycled sand. The cement paste consists of cement, recycled micropowder, admixture and water. The mass ratio of each component in each cubic meter of self-leveling mortar is as follows: 450kg of cement, 330kg of water, 140kg of recycled micropowder, 1121kg of recycled sand and 45kg of water reducer.

[0048] The cement is silicate cement and has a strength grade of 42.5.

[0049] The particle size of the regenerated micro powder is no more than 75 μm, and the activity index is greater than 70%.

[0050] The regenerated micro powder comes from particles with a particle size of no more than 75 μm screened out from the regenerated sand.

[0051] The regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The fineness modulus of the regenerated sand is 2.3-3.0, and the content of particles with a diameter less than 75 μm is 0.

[0052] The method for designing the mix ratio of the self-leveling mortar made of recycled sand from waste concrete in this embodiment comprises the following steps:

[0053] (1) According to JGJ / T 98, cement paste is prepared using cement, recycled micro powder, admixture and water. The mass of cement, recycled micro powder, admixture and water required per cubic meter of cement paste is tested by orthogonal test when the fluidity of cement paste is 200-250 mm;

[0054] (2) Regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The proportion of regenerated sand in the mixed sand is i =1, that is, all is regenerated sand, set the shape coefficient b of the regenerated sand 再生砂 is 1.65, and the stacking porosity P of regenerated sand is calculated according to JGJ 52 再生砂 =0.425;

[0055] (4) Select regenerated sand with a fineness modulus of 2.5 and a particle size of less than 75 μm and a content of 0. According to the sieve residue of each sieve in the regenerated sand screening, calculate According to standard JGJ52, the apparent density of regenerated sand is 2400kg / m 3 , the bulk density of regenerated sand is 1380kg / m 3 ;

[0056] (5) Set the thickness H of the cement paste wrapped on the surface of the self-leveling mortar 净浆 50μm;

[0057] (6) The cubic stacking model of regenerated sand (assuming 1 cubic meter) is used to design the mortar mix ratio, and the volume of regenerated sand is set as V再生砂 , according to the packing porosity P of the regenerated sand 再生砂 , shape coefficient b of regenerated sand 再生砂 , the proportion of regenerated sand in mixed sand a i , the thickness of cement paste wrapped on the surface of self-leveling mortar H 净浆 as well as Calculate V 再生砂 , V 再生砂 The calculation formula is as follows:

[0058]

[0059] The calculated V 再生砂 0.467m 3 ;

[0060] (7) According to the volume V of the regenerated sand 再生砂 The mass of the regenerated sand is calculated based on the apparent density ρapparent, and then combined with step (1), the mass ratio of each component of cement, regenerated micro powder, admixture, water and regenerated sand in each cubic meter of self-leveling mortar is obtained.

[0061] The specific results are as follows: self-leveling mortar is prepared by using recycled sand with a fineness modulus of 2.5, and the apparent density of the recycled sand is 2400kg / m 3 , the bulk density of regenerated sand is 1380kg / m 3 In each cubic meter of M30 strength grade cement mortar, there are 450kg of cement, 330kg of water, 140kg of recycled micropowder, 1121kg of recycled sand, and 45kg of water reducer. The fluidity of the mortar is 365mm and the measured compressive strength is 36.4MPa.

[0062] Example 3

[0063] The waste concrete recycled sand self-leveling mortar provided in this embodiment is mainly composed of cement paste and recycled sand. The cement paste consists of cement, recycled micropowder, admixture and water. The mass proportion of each component in each cubic meter of self-leveling mortar is as follows: 480 kg of cement, 330 kg of water, 143 kg of recycled micropowder, 1094 kg of recycled sand and 48 kg of water reducer.

[0064] The cement is silicate cement and has a strength grade of 42.5.

[0065] The particle size of the regenerated micro powder is no more than 75 μm, and the activity index is greater than 70%.

[0066] The regenerated micro powder comes from particles with a particle size of no more than 75 μm screened out from the regenerated sand.

[0067] The regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The fineness modulus of the regenerated sand is 2.3-3.0, and the content of particles with a diameter less than 75 μm is 0.

[0068] The method for designing the mix ratio of the self-leveling mortar made of recycled sand from waste concrete in this embodiment comprises the following steps:

[0069] (1) According to JGJ / T 98, cement paste is prepared using cement, recycled micro powder, admixture and water. The mass of cement, recycled micro powder, admixture and water required per cubic meter of cement paste is tested by orthogonal test when the fluidity of cement paste is 200-250 mm;

[0070] (2) Regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The proportion of regenerated sand in the mixed sand is i =1, that is, all is regenerated sand, set the shape coefficient b of the regenerated sand 再生砂 =1.65, calculate the stacking porosity P of regenerated sand according to JGJ 52 再生砂 =0.425;

[0071] (3) Select regenerated sand with a fineness modulus of 2.5 and a particle size of less than 75 μm and a content of 0. According to the sieve residue of each sieve in the regenerated sand screening, calculate The apparent density of regenerated sand is 2400kg / m 3 , the bulk density of regenerated sand is 1380kg / m 3 ;

[0072] (4) Set the thickness H of the cement paste wrapped on the surface of the self-leveling mortar 净浆 50μm;

[0073] (5) The cubic stacking model of regenerated sand (assuming 1 cubic meter) is used to design the mortar mix ratio. The volume of regenerated sand is set as V 再生砂 , according to the packing porosity P of the regenerated sand 再生砂 , shape coefficient b of regenerated sand 再生砂 , the proportion of regenerated sand in mixed sand a i , the thickness of cement paste wrapped on the surface of self-leveling mortar H 净浆 as well as Calculate V 再生砂 , V 再生砂 The calculation formula is as follows:

[0074]

[0075] The calculated V 再生砂 The volume is 0.456m 3 .

[0076] (6) According to the volume V of the regenerated sand 再生砂 The mass of the regenerated sand is calculated based on the apparent density ρapparent, and then combined with step (1), the mass ratio of each component of cement, regenerated micro powder, admixture, water and regenerated sand in each cubic meter of self-leveling mortar is obtained.

[0077] The specific results are as follows: self-leveling mortar is prepared by using recycled sand with a fineness modulus of 2.3, and the apparent density of the recycled sand is 2400kg / m 3 , the bulk density of regenerated sand is 1380kg / m 3 In each cubic meter of M30 strength grade cement mortar, there are 480kg of cement, 330kg of water, 143kg of recycled micropowder, 1094kg of recycled sand, and 48kg of water reducer. The fluidity of the mortar is 365mm and the measured compressive strength is 38.6MPa.

[0078] Example 4

[0079] The waste concrete recycled sand self-leveling mortar provided in this embodiment is mainly composed of cement paste and recycled sand. The cement paste consists of cement, recycled micropowder, admixture and water. The mass ratio of each component in each cubic meter of self-leveling mortar is as follows: 400 kg of cement, 330 kg of water, 206 kg of recycled micropowder, 1109 kg of recycled sand and 40 kg of water reducer.

[0080] The cement is silicate cement and has a strength grade of 42.5.

[0081] The particle size of the regenerated micro powder is no more than 75 μm, and the activity index is greater than 70%.

[0082] The regenerated micro powder comes from particles with a particle size of no more than 75 μm screened out from the regenerated sand.

[0083] The regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The fineness modulus of the regenerated sand is 2.3-3.0, and the content of particles with a diameter less than 75 μm is 0.

[0084] The method for designing the mix ratio of the self-leveling mortar made of recycled sand from waste concrete in this embodiment comprises the following steps:

[0085] (1) According to JGJ / T 98, cement paste is prepared using cement, recycled micro powder, admixture and water. The mass of cement, recycled micro powder, admixture and water required per cubic meter of cement paste is tested by orthogonal test when the fluidity of cement paste is 200-250 mm;

[0086] (2) Regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The proportion of regenerated sand in the mixed sand is i =1, that is, all is regenerated sand, set the shape coefficient b of the regenerated sand 再生砂=1.65, calculate the stacking porosity P of regenerated sand according to JGJ 52 再生砂 =0.425;

[0087] (3) Select regenerated sand with a fineness modulus of 2.3 and a particle size of less than 75 μm and a content of 0. According to the sieve residue of each sieve in the regenerated sand screening, calculate 5520.6m 2 / m 3 , the apparent density of regenerated sand is 2400kg / m 3 , the bulk density of regenerated sand is 1400kg / m 3 ;

[0088] (4) Set the thickness H of the cement paste wrapped on the surface of the self-leveling mortar 净浆 50μm;

[0089] (5) The cubic stacking model of regenerated sand (assuming 1 cubic meter) is used to design the mortar mix ratio. The volume of regenerated sand is set as V 再生砂 , according to the packing porosity P of the regenerated sand 再生砂 , shape coefficient b of regenerated sand 再生砂 , the proportion of regenerated sand in mixed sand a i , the thickness of cement paste wrapped on the surface of self-leveling mortar H 净浆 as well as Calculate V 再生砂 , V 再生砂 The calculation formula is as follows:

[0090]

[0091] The calculated V 再生砂 0.456m 3 ;

[0092] (6) According to the volume V of the regenerated sand 再生砂 The mass of the regenerated sand is calculated based on the apparent density ρapparent, and then combined with step (1), the mass ratio of each component of cement, regenerated micro powder, admixture, water and regenerated sand in each cubic meter of self-leveling mortar is obtained.

[0093] The specific results are as follows: self-leveling mortar is prepared by using recycled sand with a fineness modulus of 2.3, and the apparent density of the recycled sand is 2430kg / m 3 , the bulk density of regenerated sand is 1400kg / m 3 In each cubic meter of M20 strength grade cement mortar, there are 400kg of cement, 330kg of water, 206kg of recycled micropowder, 1109kg of recycled sand, and 40kg of water reducer. The fluidity of the mortar is 345mm and the measured compressive strength is 26.8MPa.

[0094] Example 5

[0095] The waste concrete recycled sand self-leveling mortar provided in this embodiment is mainly composed of cement paste and recycled sand. The cement paste consists of cement, recycled micropowder, admixture and water. The mass ratio of each component in each cubic meter of self-leveling mortar is as follows: 400 kg of cement, 330 kg of water, 175 kg of recycled micropowder, 1111 kg of recycled sand and 40 kg of water reducer.

[0096] The cement is silicate cement and has a strength grade of 42.5.

[0097] The particle size of the regenerated micro powder is no more than 75 μm, and the activity index is greater than 70%.

[0098] The regenerated micro powder comes from particles with a particle size of no more than 75 μm screened out from the regenerated sand.

[0099] The regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The fineness modulus of the regenerated sand is 2.3-3.0, and the content of particles with a diameter less than 75 μm is 0.

[0100] The method for designing the mix ratio of the self-leveling mortar made of recycled sand from waste concrete in this embodiment comprises the following steps:

[0101] (1) According to JGJ / T 98, cement paste is prepared using cement, recycled micro powder, admixture and water. The mass of cement, recycled micro powder, admixture and water required per cubic meter of cement paste is tested by orthogonal test when the fluidity of cement paste is 200-250 mm;

[0102] (2) Regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The proportion of regenerated sand in the mixed sand is i =1, that is, all is regenerated sand, set the shape coefficient b of the regenerated sand 再生砂 =1.65, calculate the stacking porosity P of regenerated sand according to JGJ 52 再生砂 =0.420;

[0103] (3) Select regenerated sand with a fineness modulus of 2.6 and a particle size of less than 75 μm and a content of 0. According to the sieve residue of each sieve in the regenerated sand screening, calculate 4595.4m 2 / m 3 The apparent density of regenerated sand is 2380kg / m 3 , the bulk density of regenerated sand is 1390kg / m 3 ;

[0104] (4) Set the thickness H of the cement paste wrapped on the surface of the self-leveling mortar 净浆 =55μm;

[0105] (5) The cubic stacking model of regenerated sand (assuming 1 cubic meter) is used to design the mortar mix ratio. The volume of regenerated sand is set as V 再生砂 , according to the packing porosity P of the regenerated sand 再生砂 , shape coefficient b of regenerated sand 再生砂 , the proportion of regenerated sand in mixed sand a i , the thickness of cement paste wrapped on the surface of self-leveling mortar H 净浆 as well as Calculate V 再生砂 , V 再生砂 The calculation formula is as follows:

[0106]

[0107] The calculated V 再生砂 0.467m 3 ;

[0108] (6) According to the volume V of the regenerated sand 再生砂 The mass of the regenerated sand is calculated based on the apparent density ρapparent, and then combined with step (1), the mass ratio of each component of cement, regenerated micro powder, admixture, water and regenerated sand in each cubic meter of self-leveling mortar is obtained.

[0109] The specific results are as follows: The self-leveling mortar is prepared by using recycled sand with a fineness modulus of 2.6, and the apparent density of the recycled sand is 2380kg / m 3 , the bulk density of regenerated sand is 1380kg / m 3 In each cubic meter of M20 strength grade cement mortar, there are 400kg of cement, 330kg of water, 175kg of recycled micropowder, 1111kg of recycled sand, and 40kg of water reducer. The fluidity of the mortar is 355mm and the measured compressive strength is 26.5MPa.

[0110] The above embodiments are only used to illustrate the present invention, and the protection scope of the present invention is not limited to the above embodiments. A person skilled in the art can achieve the purpose of the present invention based on the above disclosure of the present invention, and any improvement and deformation based on the concept of the present invention shall fall within the protection scope of the present invention, and the specific protection scope shall be subject to the claims.

Claims

1. A self-leveling mortar made of recycled sand from waste concrete, characterized in that: The self-leveling mortar is mainly prepared from cement paste and regenerated sand. The cement paste consists of cement, regenerated micropowder, admixture and water. The mass proportion of each component in each cubic meter of self-leveling mortar is as follows: 340-500kg of cement, 130-210kg of regenerated micropowder, 30-50kg of admixture, 320-340kg of water and 1080-1130kg of regenerated sand.

2. The waste concrete recycled sand self-leveling mortar according to claim 1, characterized in that: The mass ratio of each component in each cubic meter of self-leveling mortar is as follows: 400-480kg of cement, 150-206kg of recycled micropowder, 40-48kg of admixture, 325-335kg of water, and 1090-1125kg of recycled sand.

3. The self-leveling mortar made of recycled sand from waste concrete according to claim 1 or 2, characterized in that: The cement is silicate cement or ordinary silicate cement and has a strength grade of 42.

5.

4. The self-leveling mortar made of recycled sand from waste concrete according to claim 1 or 2, characterized in that: The regenerated micro powder has a particle size of no more than 75 μm and an activity index of more than 70%. The regenerated micro powder is derived from particles with a particle size of no more than 75 μm screened out from regenerated sand.

5. The self-leveling mortar made of recycled sand from waste concrete according to claim 1 or 2, characterized in that: The admixture is a commercially available water reducing agent.

6. The self-leveling mortar made of recycled sand from waste concrete according to claim 1 or 2, characterized in that: The regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The fineness modulus of the regenerated sand is 2.3-3.0, and the content of particles with a diameter less than 75 μm is 0.

7. The method for designing the mix ratio of waste concrete recycled sand self-leveling mortar according to claim 1 or 2, characterized in that: The following steps are involved: (1) According to JGJ / T 98, cement paste is prepared using cement, recycled micro powder, admixture and water. The quality of cement, recycled micro powder, admixture and water required when the fluidity of cement paste is 200-250 mm is tested by orthogonal test; (2) Regenerated sand is regenerated sand or a mixture of regenerated sand and machine-made sand. The proportion of regenerated sand in the mixed sand is set to a. i And the shape coefficient b of the regenerated sand 再生砂 , and calculate the stacking porosity P of regenerated sand according to JGJ 52 再生砂 ; (3) Select regenerated sand with a fineness modulus of 2.3 to 3.0 and a particle size of less than 75 μm and a content of 0. According to the sieve residue of each sieve in the regenerated sand screening, calculate S i is the specific surface area of ​​each level of regenerated sand, K i Refers to the percentage of sand on each sieve, N i refers to the amount of sand on each level of sand, R is the average particle size of each level of sieve, ρ 堆积 and ρ 表观 Obtained according to standard JGJ 52; (4) Set the thickness H of the cement paste wrapped on the surface of the self-leveling mortar 净浆 ; (5) The cubic stacking model of regenerated sand is used to design the mix ratio of mortar, and the volume of regenerated sand is set as V 再生砂 , according to the packing porosity P of the regenerated sand 再生砂 , shape coefficient b of regenerated sand 再生砂 , the proportion of regenerated sand in mixed sand a i , the thickness of cement paste wrapped on the surface of self-leveling mortar H 净浆 as well as Calculate V 再生砂 , V 再生砂 The calculation formula is as follows: (6) According to the volume V of the regenerated sand 再生砂 The mass of the regenerated sand is calculated based on the apparent density ρapparent, and then combined with step (1), the mass ratio of each component of cement, regenerated micro powder, admixture, water and regenerated sand in each cubic meter of self-leveling mortar is obtained.

8. The method for designing the mix ratio of waste concrete recycled sand self-leveling mortar according to claim 7 is characterized in that: The proportion of regenerated sand in the mixed sand in step (2) is i It is 0.7~1.

9. The method for designing the mix ratio of waste concrete recycled sand self-leveling mortar according to claim 7, characterized in that: The shape coefficient b of the regenerated sand in step (2) is 1.0 to 1.

5.

10. The method for designing the mix ratio of waste concrete recycled sand self-leveling mortar according to claim 7, characterized in that: In step (4), the thickness H of the cement paste wrapped on the surface of the self-leveling mortar is set 净浆 50~55μm.

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