Preparation method of shape-reconstructed porous lightweight aggregate high-strength high-performance concrete

Abstract

The invention provides a preparation method of shape-reconstructed porous lightweight aggregate high-strength high-performance concrete, which comprises the following steps: preparing lightweight aggregate, cement, fly ash, a water reducing agent and mixing water, and extracting aggregate particles with a corresponding number according to a proportion; key morphological parameters of the lightweight aggregate are obtained, wherein the key morphological parameters include the porosity correlation coefficient, the wrapping layer thickness correlation coefficient, the roundness correlation coefficient, the angularity correlation coefficient and the like; on the basis of reconstruction, the initial reconstruction coefficient of the high-strength and high-performance concrete meeting the corresponding performance requirements is calculated, reconstructed slurry is prepared according to the initial reconstruction coefficient, the reconstructed lightweight aggregate capable of being quantitatively improved is obtained, and finally the high-strength and high-performance lightweight aggregate concrete with the controllable macroscopic performance is prepared. According to the reconstructed lightweight aggregate, quantitative improvement of the structure and performance of the aggregate can be achieved, the high-strength and high-performance lightweight aggregate concrete is prepared, the strength, durability and energy-dissipating capacity of the lightweight aggregate concrete can be quantitatively controlled, and the application range of the lightweight aggregate concrete is widened.

Description

Technical Field

[0001] The invention belongs to the technical field of building materials, and in particular relates to a method for preparing morphologically reconstructed porous lightweight aggregate high-strength and high-performance concrete. Background Art

[0002] Lightweight aggregate concrete has many advantages, such as low building weight, small foundation bearing capacity, strong earthquake resistance, and good development prospects. However, due to the influence of lightweight aggregate, it is mainly used in medium and low strength concrete structures, which directly limits its further application in building structures, especially high-strength and high-performance concrete structures.

[0003] The preparation of this type of high-strength and high-performance concrete inevitably requires high-performance lightweight aggregate. The annual output of lightweight aggregate in my country has reached a considerable scale, but there are few high-quality lightweight aggregates whose main properties such as strength and water absorption index can reach the high-strength lightweight aggregate index. The lack of high-strength and high-performance lightweight aggregates has led to a lack of sufficient raw material supply for some large-scale engineering construction. The inadequate performance of lightweight aggregates also makes it difficult for the macroscopic properties of lightweight aggregate concrete, such as strength, ductility, energy dissipation capacity and durability, to meet the requirements, and it is impossible to achieve quantitative control of the strength, ductility, energy dissipation capacity and durability of lightweight aggregate concrete.

[0004] Therefore, there is an urgent need for a high-strength, high-performance lightweight aggregate concrete with high strength, good ductility, good durability and quantitative controllable macroscopic performance, so as to make full use of large amounts of lightweight aggregates such as pumice, volcanic slag, expanded clay or coal gangue, meet the design requirements of major projects, and improve its application scope and quality.

[0005] Based on this, a method for preparing morphologically reconstructed porous lightweight aggregate high-strength and high-performance concrete was proposed, which can achieve quantitative and controllable macroscopic properties such as strength, ductility and durability. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a method for preparing a morphologically reconstructed porous lightweight aggregate high-strength and high-performance concrete in view of the deficiencies of the above-mentioned prior art, so as to solve the problems raised in the above-mentioned background technology.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for preparing morphologically reconstructed porous lightweight aggregate high-strength and high-performance concrete, comprising the following steps:

[0008] S1. Prepare lightweight aggregate, river sand, cement, fly ash, water reducing agent and mixing water, wherein the mixing water is fresh water, and screen and air-dry the lightweight aggregate at room temperature;

[0009] S2. Extract a corresponding number of aggregate particles according to the proportion, and measure the porosity k1, roundness k3, and edge angle k4 of the lightweight aggregate, and take the measured average value;

[0010] S3. Based on the ductility, energy dissipation capacity, strength and chloride ion impermeability of ordinary lightweight aggregate concrete, the concrete mix ratio is designed according to the formula according to the standard, and additional water is added according to the water absorption of the lightweight aggregate in 1 hour. The coarse aggregate, cementitious material and fine aggregate are put into the mixer in the order of dry stirring for 3 minutes. After all the raw materials are fully stirred, the mixing water with a water reducer is slowly poured while stirring, and the stirring is continued until it is uniform. The concrete is poured into a mold for standard curing and specified testing to obtain the ductility, energy dissipation capacity, strength and chloride ion impermeability of ordinary lightweight aggregate concrete;

[0011] S4. Calculate the initial reconstruction coefficient, water-cement ratio α, fly ash content β and cement-to-bone ratio γ of high-strength and high-performance concrete according to the formula based on the ductility, energy dissipation capacity, strength and chloride ion impermeability of ordinary lightweight aggregate concrete;

[0012] The initial reconstruction parameters are calculated according to the following physical model:

[0013] k 1u =(l1α+m1β+n1γ)k1

[0014] k 2u =(l2α+m2β+n2γ)k2

[0015] k 3u =(l3α+m3β+n3γ)k3

[0016] k 4u =(l4α+m4β+n4γ)k4

[0017] Where: l1~l4——correlation coefficient of water-cement ratio porosity, correlation coefficient of coating thickness, correlation coefficient of roundness and correlation coefficient of edge angle;

[0018] m1~m4——correlation coefficient of fly ash content porosity, coating thickness, roundness and angularity;

[0019] n1~n4——Correlation coefficient of the porosity of the glue-bone ratio, the thickness of the coating layer, the roundness and the angle;

[0020]

[0021] Where: ——Porosity ductility correlation coefficient, energy dissipation capacity correlation coefficient, strength correlation coefficient, chloride ion impermeability correlation coefficient;

[0022] ω1, ω2, ω3, ω4——correlation coefficient of ductility, energy dissipation capacity, strength and chloride ion impermeability of the coating thickness;

[0023] λ1,λ2,λ3λ4——Correlation coefficient of roundness and ductility, correlation coefficient of energy dissipation capacity, correlation coefficient of strength, correlation coefficient of chloride ion impermeability;

[0024] ρ1, ρ2, ρ3——Correlation coefficient of edge angle ductility, correlation coefficient of energy dissipation capacity, correlation coefficient of strength, correlation coefficient of chloride ion impermeability

[0025] S5. Prepare a reconstructed slurry according to the initial reconstruction coefficient, mix the reconstructed slurry with the lightweight aggregate according to the ratio of glue to aggregate for 45-210 seconds, ensure that the slurry tightly wraps the aggregate without segregation, vibrate the lightweight aggregate after stirring for 10-20 seconds to remove excess slurry from the surface of the aggregate, spread the reinforced aggregate evenly and cure it under standard conditions for 7 days, and wait for the aggregate to dry naturally until the wrapping layer is completely hardened to obtain the reconstructed lightweight aggregate;

[0026] S6. Design the mix ratio of concrete again according to the standard, and add additional water according to the water absorption of lightweight aggregate in 1 hour. Put them into the mixer in the order of coarse aggregate, cementitious material and fine aggregate and stir them for 3 minutes. After all the raw materials are fully mixed, slowly pour in the mixing water with water reducer while stirring, continue stirring until it is uniform, and pour it into the mold for standard curing and specified testing.

[0027] As a further illustration of the present invention, the lightweight aggregate is specifically pumice, volcanic slag, ceramsite or coal gangue.

[0028] As a further illustration of the present invention, in S2 or S5, 30 aggregates are selected for every 5 kg of light aggregate, and light particles are extracted to measure the morphological parameters of the aggregates.

[0029] As a further illustration of the present invention, the test in S3 is performed using a pressure testing machine, loading at a speed of 5 kN / s, and when the axial force drops to 85% of the peak load, loading is stopped to obtain the strength of the lightweight aggregate concrete;

[0030] The ductility and energy dissipation capacity of concrete were obtained by using an electro-hydraulic servo rock triaxial instrument with a measuring range of 2000kN, a dynamic acquisition instrument and a resistance strain gauge. The loading method was displacement control and the loading speed was 0.05mm / min.

[0031] The displacement ductility coefficient μ is used to reflect the ductility change of reinforced lightweight aggregate concrete;

[0032]

[0033] Where: ε 0.8 ——The strain value corresponding to when the stress drops to 80% of the peak stress;

[0034] ε0——peak strain of concrete.

[0035] The energy dissipation coefficient η is used to quantitatively evaluate the axial compression energy dissipation capacity of the material. Based on the full stress-strain curve, the energy dissipation coefficient is calculated to obtain the energy dissipation capacity of lightweight aggregate concrete.

[0036] The chloride ion diffusion coefficient of lightweight aggregate concrete was obtained by conducting chloride ion penetration resistance test using the RCM method.

[0037] As a further explanation of the present invention, the fly ash dosage in S4 is specifically the percentage of fly ash dosage to the mass of cementitious material.

[0038] As a further illustration of the present invention, in S5, cement, fly ash and fresh water are placed in a vertical mixer and stirred for 3 to 5 minutes to prepare a reconstituted slurry.

[0039] Compared with the prior art, the present invention has the following advantages:

[0040] The reconstructed lightweight aggregate of the present invention can achieve quantitative improvement in its pore structure and performance, and formulate high-strength and high-performance lightweight aggregate concrete. The macroscopic properties of the reconstructed lightweight aggregate concrete, such as strength, durability and energy consumption capacity, can be quantified by controlling the initial reconstruction coefficient of the lightweight aggregate concrete, specifically the water-cement ratio, fly ash content and cement-to-aggregate ratio, thereby expanding the application scope of lightweight aggregate concrete. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Schematic diagram of energy consumption coefficient in an embodiment of the present invention.

[0042] Figure 2 It is the stress-strain curve of the coal gangue concrete in Experimental Example 1 of the present invention.

[0043] Figure 3 This is the stress-strain curve of pumice concrete in Experimental Example 2 of the present invention.

[0044] Figure 4 It is the stress-strain curve of ceramsite concrete of Experimental Example 3 of the present invention. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] Examples, such as Figure 1 As shown, the present invention provides a technical solution: a method for preparing a morphologically reconstructed porous lightweight aggregate high-strength and high-performance concrete, comprising the following steps:

[0047] S1. Prepare lightweight aggregate, river sand, cement, fly ash, water reducing agent and mixing water, and screen and air-dry the lightweight aggregate at room temperature;

[0048] The lightweight aggregate is specifically pumice, volcanic slag, ceramsite or coal gangue.

[0049] S2. Extract a corresponding number of aggregate particles according to the proportion, and measure the porosity k1, roundness k3, and edge angle k4 of the lightweight aggregate, and take the measured average value; select 30 aggregates for every 5 kg of lightweight aggregate, extract lightweight particles and measure the morphological parameters of the aggregate.

[0050] S3. Design the mix ratio of concrete according to the standard, add additional water according to the water absorption of lightweight aggregate in 1 hour, put them into the mixer in the order of coarse aggregate, cementitious material and fine aggregate, and stir them for 3 minutes. After all the raw materials are fully mixed, slowly pour the mixing water with water reducer while stirring, continue to stir until it is uniform, and pour it into the mold for standard curing and specified testing;

[0051] A compression testing machine was used to load at a speed of 5 kN / s. When the axial force dropped to 85% of the peak load, the loading was stopped to obtain the strength of the lightweight aggregate concrete.

[0052] The ductility and energy dissipation capacity of concrete were obtained by using an electro-hydraulic servo rock triaxial instrument with a measuring range of 2000kN, a dynamic acquisition instrument and a resistance strain gauge. The loading method was displacement control and the loading speed was 0.05mm / min.

[0053] The displacement ductility coefficient μ is used to reflect the ductility change of reinforced lightweight aggregate concrete;

[0054]

[0055] Where: ε 0.8 ——The strain value corresponding to when the stress drops to 80% of the peak stress;

[0056] ε0——peak strain of concrete.

[0057] The energy dissipation coefficient η is used to quantitatively evaluate the axial compression energy dissipation capacity of the material. Based on the full stress-strain curve, the energy dissipation coefficient is calculated to obtain the energy dissipation capacity of lightweight aggregate concrete.

[0058] Figure 1 is a schematic diagram of energy dissipation coefficient, in which U is the peak point, Y is the point corresponding to 0.8 times the peak force in the descending section, and S OUYC is the area of ​​the blue shaded part in the figure, S OABC is the rectangular area of ​​OABC;

[0059]

[0060] According to the calculation, the initial reconstruction coefficient water-cement ratio, fly ash content and cement-to-brick ratio of the lightweight aggregate concrete after reconstruction to reach 60MPa are obtained.

[0061] The chloride ion diffusion coefficient of lightweight aggregate concrete was obtained by conducting chloride ion penetration resistance test using the RCM method.

[0062] S4. Calculate the initial reconstruction coefficient, water-cement ratio α, fly ash content β and cement-to-bone ratio γ of high-strength and high-performance concrete according to the formula based on the ductility, energy dissipation capacity, strength and chloride ion impermeability of ordinary lightweight aggregate concrete;

[0063] The fly ash dosage refers to the percentage of fly ash used in the mass of cementitious materials.

[0064] The initial reconstruction parameters are calculated according to the following physical model:

[0065] k 1u =(l1α+m1β+n1γ)k1

[0066] k 2u =(l2α+m2β+n2γ)k2

[0067] k 3u =(l3α+m3β+n3γ)k3

[0068] k 4u =(l4α+m4β+n4γ)k4

[0069] Where: l1~l4——correlation coefficient of water-cement ratio porosity, correlation coefficient of coating thickness, correlation coefficient of roundness and correlation coefficient of edge angle;

[0070] m1~m4——correlation coefficient of fly ash content porosity, coating thickness, roundness and angularity;

[0071] n1~n4——Correlation coefficient of the porosity of the glue-bone ratio, the thickness of the coating layer, the roundness and the angle;

[0072] The coefficient values ​​are as follows:

[0073] Table 1 Correlation coefficients of the influence of water-cement ratio on morphological parameters

[0074]

[0075] Table 2 Correlation coefficients of the effect of fly ash content on morphological parameters

[0076]

[0077] Table 3 Correlation coefficients of the effect of the ratio of pastern to bone on morphological parameters

[0078]

[0079]

[0080] Where: ——Porosity ductility correlation coefficient, energy dissipation capacity correlation coefficient, strength correlation coefficient, chloride ion impermeability correlation coefficient;

[0081] ω1, ω2, ω3, ω4——correlation coefficient of ductility, energy dissipation capacity, strength and chloride ion impermeability of the coating thickness;

[0082] λ1,λ2,λ3λ4——Correlation coefficient of roundness and ductility, correlation coefficient of energy dissipation capacity, correlation coefficient of strength, correlation coefficient of chloride ion impermeability;

[0083] ρ1, ρ2, ρ3——Correlation coefficient of edge angle ductility, correlation coefficient of energy absorption capacity, correlation coefficient of strength, and correlation coefficient of chloride ion impermeability.

[0084] The coefficient values ​​are as follows:

[0085] Table 4 Correlation coefficients of porosity on concrete performance

[0086]

[0087] Note: k 1u is the porosity after reconstruction, k1 is the porosity before reconstruction

[0088] Table 5 Correlation coefficient of the influence of wrapping layer thickness on concrete performance

[0089]

[0090] Note: k 2u is the thickness of the package layer after reconstruction, k2 is the unit thickness before reconstruction

[0091] Table 6 Correlation coefficient of the influence of roundness on concrete properties

[0092]

[0093] Note: k 3u is the roundness after reconstruction, k3 is the roundness before reconstruction

[0094] Table 7 Correlation coefficients of the effect of edge angle on concrete performance

[0095]

[0096] Note: k 4u is the edge angle after reconstruction, and k4 is the edge angle before reconstruction.

[0097] S5. Prepare the reconstructed slurry according to the initial reconstruction coefficient, mix the reconstructed slurry with lightweight aggregate according to the ratio of glue to aggregate for 45-210s, ensure that the slurry tightly wraps the aggregate without segregation, vibrate the lightweight aggregate for 10-20s to remove excess slurry from the surface of the aggregate, spread the reinforced aggregate evenly and cure it under standard conditions for 7 days, and wait for the aggregate to dry naturally until the wrapping layer is completely hardened to obtain the reconstructed lightweight aggregate; select 30 aggregates for every 5kg of lightweight aggregate, extract lightweight particles and measure the morphological parameters of the aggregate.

[0098] Cement, fly ash and fresh water are placed in a vertical mixer and stirred for 3 to 5 minutes to prepare a reconstituted slurry.

[0099] S6. Design the mix ratio of concrete again according to the standard, and add additional water according to the water absorption of lightweight aggregate in 1 hour. Put them into the mixer in the order of coarse aggregate, cementitious material and fine aggregate and stir them for 3 minutes. After all the raw materials are fully mixed, slowly pour in the mixing water with water reducer while stirring, continue stirring until it is uniform, and pour it into the mold for standard curing and specified testing.

[0100] Experimental example 1:

[0101] To prepare ordinary gangue aggregate concrete, additional water is added according to the water absorption of gangue in one hour, and the base ratio of gangue aggregate concrete is determined as water: cement: river sand: aggregate = 145.0kg: 630.0kg: 730.0kg: 892.5kg.

[0102] A TYE-3000B pressure testing machine was used with force control selected to load at a speed of 5 kN / s. When the axial force dropped to 85% of the peak load, the loading was stopped and the strength of ordinary coal gangue concrete was 34.7 MPa.

[0103] The stress-strain curve of concrete was obtained by using an electro-hydraulic servo rock triaxial tester (TAW-2000) with a range of 2000kN, a dynamic acquisition instrument (Donghua DH5922), and a resistance strain gauge (BX120-50AA). After the test device was installed correctly, a preload test was carried out. When the data feedback from the preload test met the requirements, a formal test was carried out. The loading method selected displacement control, and the loading speed was 0.05mm / min.

[0104] The ductility of ordinary coal gangue concrete is 1.03 obtained from the stress-strain curve; the energy dissipation capacity of ordinary coal gangue concrete is 0.59.

[0105] The chloride ion diffusion coefficient was 13.23 when the chloride ion penetration resistance test was carried out by RCM method.

[0106] According to the calculation, the initial reconstruction coefficient of coal gangue concrete after reconstruction to 60MPa is 0.7 in water-cement ratio, 5% in fly ash content and 0.6 in cement-bone ratio.

[0107] The gangue aggregate was reconstructed according to the initial reconstruction coefficient of water-cement ratio of 0.6, fly ash content of 15%, and cement-to-aggregate ratio of 0.6.

[0108] To prepare reconstructed gangue aggregate concrete, additional water was added according to the water absorption of gangue in 1 hour, and the base ratio of gangue aggregate concrete was determined to be water: cement: river sand: aggregate = 145.0 kg: 630.0 kg: 730.0 kg: 892.5 kg.

[0109] As mentioned above, according to the prescribed tests, the strength of the reconstructed gangue aggregate concrete was 59.4MPa, the ductility was 1.19, the energy dissipation capacity was 0.69, and the chloride ion diffusion coefficient was 9.33.

[0110] Experimental Example 2:

[0111] Prepare ordinary pumice aggregate concrete, add additional water according to the water absorption of pumice in one hour, and determine the base ratio of pumice aggregate concrete as water: cement: river sand: aggregate = 200.0kg: 380.0kg: 832.0kg: 564.0kg.

[0112] A TYE-3000B pressure testing machine was used with force control selected to load at a speed of 5 kN / s. When the axial force dropped to 85% of the peak load, the loading was stopped and the strength of ordinary pumice concrete was 38.2 MPa.

[0113] The stress-strain curve of concrete was obtained by using an electro-hydraulic servo rock triaxial tester (TAW-2000) with a range of 2000kN, a dynamic acquisition instrument (Donghua DH5922), and a resistance strain gauge (BX120-50AA). After the test device was installed correctly, a preload test was carried out. When the data feedback from the preload test met the requirements, a formal test was carried out. The loading method selected displacement control, and the loading speed was 0.05mm / min.

[0114] The ductility of ordinary pumice concrete is 1.03 from the stress-strain curve; the energy dissipation capacity of ordinary pumice concrete is 0.59.

[0115] The chloride ion diffusion coefficient was 14.28 after the chloride ion penetration test was carried out by RCM method.

[0116] According to calculation, the initial reconstruction coefficient of pumice concrete after reconstruction to 60MPa is 0.6 in water-cement ratio, 13% in fly ash content and 0.6 in cement-bone ratio.

[0117] The pumice aggregate was reconstructed according to the initial reconstruction coefficient of water-cement ratio of 0.6, fly ash content of 13%, and cement-to-bundle ratio of 0.6.

[0118] The reconstructed pumice aggregate concrete was prepared by adding additional water according to the water absorption of the pumice in one hour, and the base ratio of the pumice aggregate concrete was determined to be water: cement: river sand: aggregate = 200.0 kg: 380.0 kg: 832.0 kg: 564.5 kg.

[0119] As above, according to the prescribed tests, the strength of the reconstructed pumice aggregate concrete was 61 MPa, the ductility was 1.10, the energy dissipation capacity was 0.62, and the chloride ion diffusion coefficient was 10.31.

[0120] Experimental Example 3:

[0121] To prepare ordinary ceramsite aggregate concrete, additional water is added according to the water absorption of ceramsite in one hour, and the base ratio of ceramsite aggregate concrete is determined as water: cement: river sand: aggregate = 180.0kg: 420.0kg: 728.0kg: 620kg.

[0122] A TYE-3000B pressure testing machine was used with force control selected to load at a speed of 5 kN / s. When the axial force dropped to 85% of the peak load, the loading was stopped and the strength of ordinary ceramsite concrete was 31.1 MPa.

[0123] The stress-strain curve of concrete was obtained by using an electro-hydraulic servo rock triaxial tester (TAW-2000) with a range of 2000kN, a dynamic acquisition instrument (Donghua DH5922), and a resistance strain gauge (BX120-50AA). After the test device was installed correctly, a preload test was carried out. When the data feedback from the preload test met the requirements, a formal test was carried out. The loading method selected displacement control, and the loading speed was 0.05mm / min.

[0124] The ductility of ordinary ceramsite concrete is 1.10 obtained from the stress-strain curve; the energy dissipation capacity of ordinary ceramsite concrete is 0.64.

[0125] The chloride ion penetration resistance test was carried out by RCM method, and the chloride ion diffusion coefficient was found to be 14.18.

[0126] According to calculation, the initial reconstruction coefficient of ceramsite concrete after reconstruction to 60MPa is 0.5 in water-cement ratio, 9% in fly ash content and 0.6 in cement-bone ratio.

[0127] The ceramsite aggregate was reconstructed according to the initial reconstruction coefficient of water-cement ratio of 0.5, fly ash content of 9%, and cement-to-bundle ratio of 0.6.

[0128] The reconstructed ceramsite aggregate concrete was prepared by adding additional water according to the water absorption of ceramsite in one hour, and the base ratio of ceramsite aggregate concrete was determined to be water: cement: river sand: aggregate = 180.0 kg: 420.0 kg: 728.0 kg: 620 kg.

[0129] As above, according to the prescribed tests, the strength of the reconstructed ceramsite aggregate concrete was 59.2 MPa, the ductility was 1.15, the energy dissipation capacity was 0.66, and the chloride ion diffusion coefficient was 9.48.

[0130] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0131] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a morphologically reconstructed porous lightweight aggregate high-strength and high-performance concrete, characterized in that: The following steps are involved: S1. Prepare lightweight aggregate, river sand, cement, fly ash, water reducing agent and mixing water, and screen and air-dry the lightweight aggregate at room temperature; S2. Extract a corresponding number of aggregate particles according to the proportion, and measure the porosity k1, roundness k3, and edge angle k4 of the lightweight aggregate, and take the measured average value; S3. Design the mix ratio of concrete according to the standard, add additional water according to the water absorption of lightweight aggregate in 1 hour, put into the mixer in the order of coarse aggregate, cementitious material and fine aggregate, and stir for 3 minutes. After all the raw materials are fully mixed, slowly pour the mixing water with water reducer while stirring, continue to stir until uniform, pour it into the mold for standard curing and specified testing, and obtain the ductility, energy dissipation capacity, strength and chloride ion impermeability of ordinary lightweight aggregate concrete; S4. Calculate the initial reconstruction coefficient, water-cement ratio α, fly ash content β and cement-to-bone ratio γ of high-strength and high-performance concrete according to the formula based on the ductility, energy dissipation capacity, strength and chloride ion impermeability of ordinary lightweight aggregate concrete; The initial reconstruction parameters are calculated according to the following physical model: k 1u =(l1α+m1β+n1γ)k1 k 2u =(l2α+m2β+n2γ)k2 k 3u =(l3α+m3β+n3γ)k3 k 4u =(l4α+m4β+n4γ)k4 Where: l1~l4——correlation coefficient of water-cement ratio porosity, correlation coefficient of coating thickness, correlation coefficient of roundness and correlation coefficient of edge angle; m1~m4——correlation coefficient of fly ash content porosity, coating thickness, roundness and angularity; n1~n4——Correlation coefficient of the porosity of the glue-bone ratio, the thickness of the coating layer, the roundness and the angle; Where: ——Porosity ductility correlation coefficient, energy dissipation capacity correlation coefficient, strength correlation coefficient, chloride ion impermeability correlation coefficient; ω1, ω2, ω3, ω4——correlation coefficient of ductility, energy dissipation capacity, strength and chloride ion impermeability of the coating thickness; λ1,λ2,λ3λ4——Correlation coefficient of roundness and ductility, correlation coefficient of energy dissipation capacity, correlation coefficient of strength, correlation coefficient of chloride ion impermeability; ρ1, ρ2, ρ3——Correlation coefficient of edge angle ductility, correlation coefficient of energy dissipation capacity, correlation coefficient of strength, correlation coefficient of chloride ion impermeability; S5. Prepare a reconstructed slurry according to the initial reconstruction coefficient, mix the reconstructed slurry with the lightweight aggregate according to the ratio of glue to aggregate for 45-210 seconds, ensure that the slurry tightly wraps the aggregate without segregation, vibrate the lightweight aggregate after stirring for 10-20 seconds to remove excess slurry from the surface of the aggregate, spread the reinforced aggregate evenly and cure it under standard conditions for 7 days, and wait for the aggregate to dry naturally until the wrapping layer is completely hardened to obtain the reconstructed lightweight aggregate; S6. Design the mix ratio of concrete again according to the standard, and add additional water according to the water absorption of lightweight aggregate in 1 hour. Put them into the mixer in the order of coarse aggregate, cementitious material and fine aggregate and stir them for 3 minutes. After all the raw materials are fully mixed, slowly pour in the mixing water with water reducer while stirring, continue stirring until it is uniform, and pour it into the mold for standard curing and specified testing.

2. The method for preparing a morphologically reconstructed porous lightweight aggregate high-strength and high-performance concrete according to claim 1, characterized in that: The lightweight aggregate is specifically pumice, volcanic slag, ceramsite or coal gangue.

3. The method for preparing a morphologically reconstructed porous lightweight aggregate high-strength and high-performance concrete according to claim 1, characterized in that: In S2 or S5, 30 aggregates are selected for every 5 kg of light aggregate, and light particles are extracted to measure the morphological parameters of the aggregates.

4. The method for preparing a morphologically reconstructed porous lightweight aggregate high-strength and high-performance concrete according to claim 1, characterized in that: The test in S3 was conducted using a compression testing machine with loading at a rate of 5 kN / s. When the axial force dropped to 85% of the peak load, loading was stopped to obtain the strength of lightweight aggregate concrete; The ductility and energy dissipation capacity of concrete were obtained by using an electro-hydraulic servo rock triaxial instrument with a measuring range of 2000kN, a dynamic acquisition instrument and a resistance strain gauge. The loading method was displacement control and the loading speed was 0.05mm / min. The displacement ductility coefficient μ is used to reflect the ductility change of reinforced lightweight aggregate concrete; Where: ε 0.8 ——The strain value corresponding to when the stress drops to 80% of the peak stress; ε0——peak strain of concrete; The energy dissipation coefficient η is used to quantitatively evaluate the axial compression energy dissipation capacity of the material. Based on the full stress-strain curve, the energy dissipation coefficient is calculated to obtain the energy dissipation capacity of lightweight aggregate concrete. The chloride ion diffusion coefficient of lightweight aggregate concrete was obtained by conducting chloride ion penetration resistance test using the RCM method.

5. The method for preparing a morphologically reconstructed porous lightweight aggregate high-strength and high-performance concrete according to claim 1, characterized in that: The fly ash dosage in S4 is specifically the percentage of fly ash used in the mass of cementitious materials.

6. According to the method for preparing a morphologically reconstructed porous lightweight aggregate high-strength and high-performance concrete according to claim 1, in S5, cement, fly ash and fresh water are placed in a vertical mixer and stirred for 3 to 5 minutes to prepare a reconstructed slurry.

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