High-grade low-carbon ultra-high-performance self-compacting concrete containing coarse aggregate

Abstract

The invention relates to the technical field of building materials, and particularly discloses high-grade low-carbon ultra-high-performance self-compacting concrete containing coarse aggregate. The high-grade low-carbon ultra-high-performance self-compacting concrete containing the coarse aggregate comprises the following components in parts by mass: 100 parts of water; 185 to 187 parts of cement; 30 to 32 parts of fly ash; 15 to 16 parts of phosphorus slag; 370 to 375 parts of fine aggregate; 730 to 750 parts of modified recycled coarse aggregate; 70-75 parts of an inorganic whisker filler; 6.2 to 6.6 parts of an additive; the modified recycled coarse aggregate is prepared by soaking and modifying recycled coarse aggregate in a modifying solution; the modified liquid is a compound of water, mercaptoacetic acid, octadecyl trimethyl ammonium chloride and oleamide propyl amine oxide. The method has the advantage of better improving the strength of the concrete doped with a large amount of recycled aggregate.

Description

Technical Field

[0001] The invention relates to the field of building materials, in particular to a high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate. Background Art

[0002] Concrete is one of the main civil engineering materials. It is an artificial stone formed by mixing cementitious materials, aggregates, water, admixtures, etc. and curing and hardening.

[0003] Cementitious materials are mainly made of cement, which becomes a slurry when mixed with water. It can harden in the air or in water, and can firmly bond sand, stone and other materials together.

[0004] The production process of cement mainly uses limestone and clay as the main raw materials, which are crushed, batched and ground into raw materials, and then fed into cement kilns to calcine into clinker. The clinker is then ground with an appropriate amount of gypsum. Therefore, a large amount of energy is consumed in the calcination process of cement production, resulting in high carbon emissions. As the use of concrete continues to increase, the use of cement continues to increase, making it difficult for concrete materials to meet the needs of green building materials.

[0005] In order to reduce carbon emissions, fly ash, phosphorus slag and other materials will be used to partially replace cement to reduce the amount of cement used, thereby achieving the effect of reducing carbon emissions. Combined with the use of recycled coarse aggregate made from waste concrete, the consumption of natural stone can be reduced, which can better reduce carbon emissions and be more environmentally friendly.

[0006] However, recycled aggregates are formed by destroying waste concrete through external force. Under external force destruction, recycled aggregates will form more cracks. Compared with the use of natural stone, the density of concrete will decrease, resulting in a decrease in the strength of the produced concrete, affecting the performance of the concrete. To solve this problem, powdered or even nano-scale fillers are usually added to fill the cracks in the recycled aggregates. However, during the concrete mixing process, the fillers tend to be evenly distributed in the concrete, resulting in a relatively general effect of filling the fillers into the cracks of the recycled aggregates, resulting in a relatively general effect of improving the strength of the concrete. Therefore, there is still room for improvement. Summary of the invention

[0007] In order to better improve the strength of concrete with a large amount of recycled aggregate, the present application provides a high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate.

[0008] The present application provides a high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate, which adopts the following technical solution: A high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate, comprising the following components in parts by mass: 100 parts water; Cement 185-187 parts; 30-32 parts of fly ash; Phosphorus slag 15-16 parts; 370-375 parts of fine aggregate; 730-750 parts of modified recycled coarse aggregate; 70-75 parts of inorganic whisker filler; Admixture 6.2-6.6 parts; The modified recycled coarse aggregate is prepared by immersing the recycled coarse aggregate in a modifying liquid for modification; The modified liquid is a compound of water, thioglycolic acid, octadecyltrimethylammonium chloride and oleamidopropylamine oxide.

[0009] By adopting the above technical scheme, after the recycled coarse aggregate is modified by using a modifying liquid prepared by mixing water, thioglycolic acid, octadecyltrimethylammonium chloride and oleic acid amide propylamine oxide, during the concrete mixing process, the inorganic whisker filler can better fill the cracks of the modified recycled coarse aggregate, so that the modified recycled coarse aggregate is not easy to produce weak points, thereby significantly improving the strength of the concrete after curing, which can be close to the strength level of all natural stones. The use of modified recycled coarse aggregate can also make the fluidity of the concrete mixture better and have a good self-compacting effect, so that the high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate can reduce carbon emissions and have better performance.

[0010] Preferably, in the modified liquid, the mass ratio of water, thioglycolic acid, octadecyltrimethylammonium chloride and oleamidopropylamine oxide is 100:1-2:7-8:5-6.

[0011] By adopting the above technical scheme and specifically selecting the mass ratio of water, thioglycolic acid, octadecyltrimethylammonium chloride and oleamidopropylamine oxide, the modification effect is better, the obtained concrete is closer to the strength level of all natural stones, and the quality is better.

[0012] Preferably, the inorganic whisker filler is calcium carbonate whisker.

[0013] By adopting the above technical solution and calcium carbonate whiskers, the reinforcement effect is better and the strength of concrete is better improved.

[0014] Preferably, the recycled coarse aggregate is made from waste concrete and has a particle size of 10-15 mm.

[0015] By adopting the above technical solution, the particle size is 10-15mm, so that the strength of the concrete is higher and the needs of high-strength engineering are better met.

[0016] Preferably, the admixture is a compound of a water reducing agent and an early strength agent.

[0017] By adopting the above technical solution, by adding a water reducing agent, the fluidity of the concrete mixture can be better improved, so that the self-compacting effect is better. By adding an early strength agent, the retarding effect brought by the phosphorus slag can be offset, so that the strength of the concrete is higher and the construction is convenient.

[0018] Preferably, the mass ratio of the water reducing agent to the early strength agent is 2.9-3.1:3.3-3.5.

[0019] By adopting the above technical solution and specifically selecting the mass ratio of the water reducing agent and the early strength agent, the construction performance of the concrete is improved.

[0020] Preferably, the water reducer is a polycarboxylate water reducer.

[0021] By adopting the above technical scheme and specifically selecting the polycarboxylate water-reducing agent, the water-reducing effect is better, the dosage is less, the economic value is higher, and the concrete performance is better.

[0022] Preferably, the early strength agent is calcium formate.

[0023] By adopting the above technical solution and specifically selecting calcium formate, the early strength effect is better and the concrete performance is better.

[0024] In summary, this application has the following beneficial effects: 1. Since the present application uses a modifying liquid composed of water, thioglycolic acid, octadecyltrimethylammonium chloride and oleamidopropylamine oxide to modify the recycled coarse aggregate, during the concrete mixing process, the inorganic whisker filler can better fill the cracks of the modified recycled coarse aggregate, making it difficult for the modified recycled coarse aggregate to produce weak points, thereby significantly improving the strength of the concrete after curing, which can be close to the strength level of all natural stones. The use of modified recycled coarse aggregate can also make the fluidity of the concrete mixture better and have a good self-compacting effect, so that the high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate can reduce carbon emissions and have better performance.

[0025] 2. In the present application, it is preferred to specifically select the mass ratio of water, thioglycolic acid, octadecyltrimethylammonium chloride and oleamidopropylamine oxide so that the modification effect is better, the obtained concrete is closer to the strength level of all natural stones, and the quality is better. DETAILED DESCRIPTION

[0026] The present application is further described in detail below with reference to the embodiments.

[0027] Example 1 A high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is prepared from the following components.

[0028] Water, cement, fly ash, phosphorus slag, fine aggregate, modified recycled coarse aggregate, inorganic whisker filler, admixtures.

[0029] The cement is ordinary Portland cement, Runfeng cement, factory specification: P.O42.5R.

[0030] The fly ash is sourced from commercially available, first-grade fly ash.

[0031] The phosphorus slag is commercially available and has a particle size of ≤80 μm.

[0032] The fine aggregate was river sand, which was commercially available and had a mesh size of 20-40.

[0033] The inorganic whisker filler is calcium carbonate whisker purchased from Hubei Dali Chemical Co., Ltd., with a length of 2-5 μm.

[0034] The admixture is a compound of water reducing agent and early strength agent.

[0035] The water reducer is polycarboxylic acid water reducer, which was purchased from Jinan Quanchi New Materials Co., Ltd.

[0036] The early strength agent is calcium formate, which was purchased from Hubei Mingtuo Biotechnology Co., Ltd.

[0037] The modified recycled coarse aggregate is prepared by immersing the recycled coarse aggregate in a modifying liquid for modification. The recycled coarse aggregate is prepared from waste concrete and has a particle size of 10-15 mm.

[0038] The preparation method of modified recycled coarse aggregate is as follows: Step 01), put 1000kg water, 10kg thioglycolic acid, 70kg octadecyltrimethylammonium chloride, and 50kg oleamidopropylamine oxide into a stirring tank, rotate at 120r / min, stir for 15min, and obtain a modified liquid.

[0039] Step 02), put 1000kg of modified liquid and 1000kg of recycled coarse aggregate into a stirring tank, rotate at 60r / min, continue stirring for 1h, filter, and air-dry naturally to obtain modified recycled coarse aggregate.

[0040] Thioglycolic acid is commercially available, CAS number: 68-11-1.

[0041] Octadecyltrimethylammonium chloride is commercially available, CAS number: 112-03-8.

[0042] Oleic acid amide propyl amine oxide was purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0043] The preparation method of high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is as follows: Step 1), 185kg cement, 30kg fly ash, 15kg phosphorus slag, 370kg river sand, 730kg modified recycled coarse aggregate, and 70kg calcium carbonate whisker are put into a stirring tank at a speed of 120r / min and stirred for 10min to obtain a premix.

[0044] Step 2), add 100kg water, 2.9kg polycarboxylate water reducer, 3.3kg calcium formate to the premix, rotate at 120r / min, stir for 5min, and obtain a concrete mixture.

[0045] Step 3), injecting the concrete mixture into the mold, sprinkling water for curing for 3 days, demoulding, sprinkling water for curing for 7 days, and standing for curing for 28 days to obtain a high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate.

[0046] Example 2 A high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is prepared from the following components.

[0047] Water, cement, fly ash, phosphorus slag, fine aggregate, modified recycled coarse aggregate, inorganic whisker filler, admixtures.

[0048] The cement is ordinary Portland cement, Runfeng cement, factory specification: P.O42.5R.

[0049] The fly ash is sourced from commercially available, first-grade fly ash.

[0050] The phosphorus slag is commercially available and has a particle size of ≤80 μm.

[0051] The fine aggregate was river sand, which was commercially available and had a mesh size of 20-40.

[0052] The inorganic whisker filler is calcium carbonate whisker purchased from Hubei Dali Chemical Co., Ltd., with a length of 2-5 μm.

[0053] The admixture is a compound of water reducing agent and early strength agent.

[0054] The water reducer is polycarboxylic acid water reducer, which was purchased from Jinan Quanchi New Materials Co., Ltd.

[0055] The early strength agent is calcium formate, which was purchased from Hubei Mingtuo Biotechnology Co., Ltd.

[0056] The modified recycled coarse aggregate is prepared by immersing the recycled coarse aggregate in a modifying liquid for modification. The recycled coarse aggregate is prepared from waste concrete and has a particle size of 10-15 mm.

[0057] The preparation method of modified recycled coarse aggregate is as follows: Step 01), put 1000kg water, 15kg thioglycolic acid, 75kg octadecyltrimethylammonium chloride, and 55kg oleamidopropylamine oxide into a stirring tank, rotate at 120r / min, stir for 15min, and obtain a modified liquid.

[0058] Step 02), put 1000kg of modified liquid and 1000kg of recycled coarse aggregate into a stirring tank, rotate at 60r / min, continue stirring for 1h, filter, and air-dry naturally to obtain modified recycled coarse aggregate.

[0059] Thioglycolic acid is commercially available, CAS number: 68-11-1.

[0060] Octadecyltrimethylammonium chloride is commercially available, CAS number: 112-03-8.

[0061] Oleic acid amide propyl amine oxide was purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0062] The preparation method of high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is as follows: Step 1), 183kg cement, 31kg fly ash, 15.5kg phosphorus slag, 372kg river sand, 740kg modified recycled coarse aggregate, and 72kg calcium carbonate whisker are put into a stirring tank at a speed of 120r / min and stirred for 10min to obtain a premix.

[0063] Step 2), add 100kg water, 3kg polycarboxylate water reducer, 3.4kg calcium formate to the premix, rotate at 120r / min, stir for 5min, and obtain a concrete mixture.

[0064] Step 3), injecting the concrete mixture into the mold, sprinkling water for curing for 3 days, demoulding, sprinkling water for curing for 7 days, and standing for curing for 28 days to obtain a high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate.

[0065] Example 3 A high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is prepared from the following components.

[0066] Water, cement, fly ash, phosphorus slag, fine aggregate, modified recycled coarse aggregate, inorganic whisker filler, admixtures.

[0067] The cement is ordinary Portland cement, Runfeng cement, factory specification: P.O42.5R.

[0068] The fly ash is sourced from commercially available, first-grade fly ash.

[0069] The phosphorus slag is commercially available and has a particle size of ≤80 μm.

[0070] The fine aggregate was river sand, which was commercially available and had a mesh size of 20-40.

[0071] The inorganic whisker filler is calcium carbonate whisker purchased from Hubei Dali Chemical Co., Ltd., with a length of 2-5 μm.

[0072] The admixture is a compound of water reducing agent and early strength agent.

[0073] The water reducer is polycarboxylic acid water reducer, which was purchased from Jinan Quanchi New Materials Co., Ltd.

[0074] The early strength agent is calcium formate, which was purchased from Hubei Mingtuo Biotechnology Co., Ltd.

[0075] The modified recycled coarse aggregate is prepared by immersing the recycled coarse aggregate in a modifying liquid for modification. The recycled coarse aggregate is prepared from waste concrete and has a particle size of 10-15 mm.

[0076] The preparation method of modified recycled coarse aggregate is as follows: Step 01), put 1000kg water, 20kg thioglycolic acid, 80kg octadecyltrimethylammonium chloride, and 60kg oleamidopropylamine oxide into a stirring tank, rotate at 120r / min, stir for 15min, and obtain a modified liquid.

[0077] Step 02), put 1000kg of modified liquid and 1000kg of recycled coarse aggregate into a stirring tank, rotate at 60r / min, continue stirring for 1h, filter, and air-dry naturally to obtain modified recycled coarse aggregate.

[0078] Thioglycolic acid is commercially available, CAS number: 68-11-1.

[0079] Octadecyltrimethylammonium chloride is commercially available, CAS number: 112-03-8.

[0080] Oleic acid amide propyl amine oxide was purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0081] The preparation method of high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is as follows: Step 1), 187kg cement, 32kg fly ash, 16kg phosphorus slag, 375kg river sand, 750kg modified recycled coarse aggregate, and 75kg calcium carbonate whisker are put into a stirring tank at a speed of 120r / min and stirred for 10min to obtain a premix.

[0082] Step 2), add 100kg water, 3.1kg polycarboxylate water reducer, and 3.5kg calcium formate to the premix, rotate at 120r / min, stir for 5min, and obtain a concrete mixture.

[0083] Step 3), injecting the concrete mixture into the mold, sprinkling water for curing for 3 days, demoulding, sprinkling water for curing for 7 days, and standing for curing for 28 days to obtain a high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate.

[0084] Comparative Example 1 A high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is prepared from the following components.

[0085] Water, cement, fly ash, phosphorus slag, fine aggregate, modified recycled coarse aggregate, inorganic whisker filler, admixtures.

[0086] The cement is ordinary Portland cement, Runfeng cement, factory specification: P.O42.5R.

[0087] The fly ash is sourced from commercially available, first-grade fly ash.

[0088] The phosphorus slag is commercially available and has a particle size of ≤80 μm.

[0089] The fine aggregate was river sand, which was commercially available and had a mesh size of 20-40.

[0090] The inorganic whisker filler is calcium carbonate whisker purchased from Hubei Dali Chemical Co., Ltd., with a length of 2-5 μm.

[0091] The admixture is a compound of water reducing agent and early strength agent.

[0092] The water reducer is polycarboxylic acid water reducer, which was purchased from Jinan Quanchi New Materials Co., Ltd.

[0093] The early strength agent is calcium formate, which was purchased from Hubei Mingtuo Biotechnology Co., Ltd.

[0094] The modified recycled coarse aggregate is prepared by immersing the recycled coarse aggregate in a modifying liquid for modification. The recycled coarse aggregate is prepared from waste concrete and has a particle size of 10-15 mm.

[0095] The preparation method of modified recycled coarse aggregate is as follows: Step 01), put 1000kg water, 15kg diethanolamine, 75kg octadecyltrimethylammonium chloride, and 55kg oleic acid amide propyl amine oxide into a stirring tank, rotate at 120r / min, stir for 15min, and obtain a modified liquid.

[0096] Step 02), put 1000kg of modified liquid and 1000kg of recycled coarse aggregate into a stirring tank, rotate at 60r / min, continue stirring for 1h, filter, and air-dry naturally to obtain modified recycled coarse aggregate.

[0097] Diethanolamine is commercially available, CAS number: 111-42-2.

[0098] Octadecyltrimethylammonium chloride is commercially available, CAS number: 112-03-8.

[0099] Oleic acid amide propyl amine oxide was purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0100] The preparation method of high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is as follows: Step 1), 183kg cement, 31kg fly ash, 15.5kg phosphorus slag, 372kg river sand, 740kg modified recycled coarse aggregate, and 72kg calcium carbonate whisker are put into a stirring tank at a speed of 120r / min and stirred for 10min to obtain a premix.

[0101] Step 2), add 100kg water, 3kg polycarboxylate water reducer, 3.4kg calcium formate to the premix, rotate at 120r / min, stir for 5min, and obtain a concrete mixture.

[0102] Step 3), injecting the concrete mixture into the mold, sprinkling water for curing for 3 days, demoulding, sprinkling water for curing for 7 days, and standing for curing for 28 days to obtain a high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate.

[0103] Comparative Example 2 A high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is prepared from the following components.

[0104] Water, cement, fly ash, phosphorus slag, fine aggregate, modified recycled coarse aggregate, inorganic whisker filler, admixtures.

[0105] The cement is ordinary Portland cement, Runfeng cement, factory specification: P.O42.5R.

[0106] The fly ash is sourced from commercially available, first-grade fly ash.

[0107] The phosphorus slag is commercially available and has a particle size of ≤80 μm.

[0108] The fine aggregate was river sand, which was commercially available and had a mesh size of 20-40.

[0109] The inorganic whisker filler is calcium carbonate whisker purchased from Hubei Dali Chemical Co., Ltd., with a length of 2-5 μm.

[0110] The admixture is a compound of water reducing agent and early strength agent.

[0111] The water reducer is polycarboxylic acid water reducer, which was purchased from Jinan Quanchi New Materials Co., Ltd.

[0112] The early strength agent is calcium formate, which was purchased from Hubei Mingtuo Biotechnology Co., Ltd.

[0113] The modified recycled coarse aggregate is prepared by immersing the recycled coarse aggregate in a modifying liquid for modification. The recycled coarse aggregate is prepared from waste concrete and has a particle size of 10-15 mm.

[0114] The preparation method of modified recycled coarse aggregate is as follows: Step 01), put 1000kg water, 15kg thioglycolic acid, 75kg lauryl amide propyl hydroxysulfobetaine, and 55kg oleamide propyl amine oxide into a stirring tank, rotate at 120r / min, stir for 15min, and obtain a modified liquid.

[0115] Step 02), put 1000kg of modified liquid and 1000kg of recycled coarse aggregate into a stirring tank, rotate at 60r / min, continue stirring for 1h, filter, and air-dry naturally to obtain modified recycled coarse aggregate.

[0116] Thioglycolic acid is commercially available, CAS number: 68-11-1.

[0117] Lauramidopropyl hydroxysulfobetaine is commercially available, CAS number: 13197-76-7.

[0118] Oleic acid amide propyl amine oxide was purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0119] The preparation method of high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is as follows: Step 1), 183kg cement, 31kg fly ash, 15.5kg phosphorus slag, 372kg river sand, 740kg modified recycled coarse aggregate, and 72kg calcium carbonate whisker are put into a stirring tank at a speed of 120r / min and stirred for 10min to obtain a premix.

[0120] Step 2), add 100kg water, 3kg polycarboxylate water reducer, 3.4kg calcium formate to the premix, rotate at 120r / min, stir for 5min, and obtain a concrete mixture.

[0121] Step 3), injecting the concrete mixture into the mold, sprinkling water for curing for 3 days, demoulding, sprinkling water for curing for 7 days, and standing for curing for 28 days to obtain a high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate.

[0122] Comparative Example 3 A high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is prepared from the following components.

[0123] Water, cement, fly ash, phosphorus slag, fine aggregate, modified recycled coarse aggregate, inorganic whisker filler, admixtures.

[0124] The cement is ordinary Portland cement, Runfeng cement, factory specification: P.O42.5R.

[0125] The fly ash is sourced from commercially available, first-grade fly ash.

[0126] The phosphorus slag is commercially available and has a particle size of ≤80 μm.

[0127] The fine aggregate was river sand, which was commercially available and had a mesh size of 20-40.

[0128] The inorganic whisker filler is calcium carbonate whisker purchased from Hubei Dali Chemical Co., Ltd., with a length of 2-5 μm.

[0129] The admixture is a compound of water reducing agent and early strength agent.

[0130] The water reducer is polycarboxylic acid water reducer, which was purchased from Jinan Quanchi New Materials Co., Ltd.

[0131] The early strength agent is calcium formate, which was purchased from Hubei Mingtuo Biotechnology Co., Ltd.

[0132] The modified recycled coarse aggregate is prepared by immersing the recycled coarse aggregate in a modifying liquid for modification. The recycled coarse aggregate is prepared from waste concrete and has a particle size of 10-15 mm.

[0133] The preparation method of modified recycled coarse aggregate is as follows: Step 01), put 1000kg water, 15kg thioglycolic acid, 75kg octadecyltrimethylammonium chloride, 55kg sodium polyoxyethylene fatty alcohol ether sulfate into a stirring tank, rotate at 120r / min, stir for 15min, and obtain a modified liquid.

[0134] Step 02), put 1000kg of modified liquid and 1000kg of recycled coarse aggregate into a stirring tank, rotate at 60r / min, continue stirring for 1h, filter, and air-dry naturally to obtain modified recycled coarse aggregate.

[0135] Thioglycolic acid is commercially available, CAS number: 68-11-1.

[0136] Octadecyltrimethylammonium chloride is commercially available, CAS number: 112-03-8.

[0137] Sodium fatty alcohol polyoxyethylene ether sulfate is commercially available, CAS number: 9004-82-4.

[0138] The preparation method of high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is as follows: Step 1), 183kg cement, 31kg fly ash, 15.5kg phosphorus slag, 372kg river sand, 740kg modified recycled coarse aggregate, and 72kg calcium carbonate whisker are put into a stirring tank at a speed of 120r / min and stirred for 10min to obtain a premix.

[0139] Step 2), add 100kg water, 3kg polycarboxylate water reducer, 3.4kg calcium formate to the premix, rotate at 120r / min, stir for 5min, and obtain a concrete mixture.

[0140] Step 3), injecting the concrete mixture into the mold, sprinkling water for curing for 3 days, demoulding, sprinkling water for curing for 7 days, and standing for curing for 28 days to obtain a high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate.

[0141] Comparative Example 4 A high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is prepared from the following components.

[0142] Water, cement, fly ash, phosphorus slag, fine aggregate, modified recycled coarse aggregate, inorganic whisker filler, admixtures.

[0143] The cement is ordinary Portland cement, Runfeng cement, factory specification: P.O42.5R.

[0144] The fly ash is sourced from commercially available, first-grade fly ash.

[0145] The phosphorus slag is commercially available and has a particle size of ≤80 μm.

[0146] The fine aggregate was river sand, which was commercially available and had a mesh size of 20-40.

[0147] The inorganic whisker filler is calcium carbonate whisker purchased from Hubei Dali Chemical Co., Ltd., with a length of 2-5 μm.

[0148] The admixture is a compound of water reducing agent and early strength agent.

[0149] The water reducer is polycarboxylic acid water reducer, which was purchased from Jinan Quanchi New Materials Co., Ltd.

[0150] The early strength agent is calcium formate, which was purchased from Hubei Mingtuo Biotechnology Co., Ltd.

[0151] The modified recycled coarse aggregate is prepared by immersing the recycled coarse aggregate in a modifying liquid for modification. The recycled coarse aggregate is prepared from waste concrete and has a particle size of 10-15 mm.

[0152] The preparation method of modified recycled coarse aggregate is as follows: Step 01), put 1000kg water, 15kg diethanolamine, 75kg lauramide propyl hydroxysulfobetaine, and 55kg sodium polyoxyethylene fatty alcohol ether sulfate into a stirring tank, rotate at 120r / min, stir for 15min, and obtain a modified liquid.

[0153] Step 02), put 1000kg of modified liquid and 1000kg of recycled coarse aggregate into a stirring tank, rotate at 60r / min, continue stirring for 1h, filter, and air-dry naturally to obtain modified recycled coarse aggregate.

[0154] Diethanolamine is commercially available, CAS number: 111-42-2.

[0155] Lauramidopropyl hydroxysulfobetaine is commercially available, CAS number: 13197-76-7.

[0156] Sodium fatty alcohol polyoxyethylene ether sulfate is commercially available, CAS number: 9004-82-4.

[0157] The preparation method of high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is as follows: Step 1), 183kg cement, 31kg fly ash, 15.5kg phosphorus slag, 372kg river sand, 740kg modified recycled coarse aggregate, and 72kg calcium carbonate whisker are put into a stirring tank at a speed of 120r / min and stirred for 10min to obtain a premix.

[0158] Step 2), add 100kg water, 3kg polycarboxylate water reducer, 3.4kg calcium formate to the premix, rotate at 120r / min, stir for 5min, and obtain a concrete mixture.

[0159] Step 3), injecting the concrete mixture into the mold, sprinkling water for curing for 3 days, demoulding, sprinkling water for curing for 7 days, and standing for curing for 28 days to obtain a high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate.

[0160] Comparative Example 5 A high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is prepared from the following components.

[0161] Water, cement, fly ash, phosphorus slag, fine aggregate, recycled coarse aggregate, inorganic whisker filler, admixtures.

[0162] The cement is ordinary Portland cement, Runfeng cement, factory specification: P.O42.5R.

[0163] The fly ash is sourced from commercially available, first-grade fly ash.

[0164] The phosphorus slag is commercially available and has a particle size of ≤80 μm.

[0165] The fine aggregate was river sand, which was commercially available and had a mesh size of 20-40.

[0166] The inorganic whisker filler is calcium carbonate whisker purchased from Hubei Dali Chemical Co., Ltd., with a length of 2-5 μm.

[0167] The admixture is a compound of water reducing agent and early strength agent.

[0168] The water reducer is polycarboxylic acid water reducer, which was purchased from Jinan Quanchi New Materials Co., Ltd.

[0169] The early strength agent is calcium formate, which was purchased from Hubei Mingtuo Biotechnology Co., Ltd.

[0170] Recycled coarse aggregate is made from waste concrete and has a particle size of 10-15mm.

[0171] The preparation method of high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate is as follows: Step 1), 183kg cement, 31kg fly ash, 15.5kg phosphorus slag, 372kg river sand, 740kg recycled coarse aggregate, and 72kg calcium carbonate whisker are put into a stirring tank at a speed of 120r / min and stirred for 10min to obtain a premix.

[0172] Step 2), add 100kg water, 3kg polycarboxylate water reducer, 3.4kg calcium formate to the premix, rotate at 120r / min, stir for 5min, and obtain a concrete mixture.

[0173] Step 3), injecting the concrete mixture into the mold, sprinkling water for curing for 3 days, demoulding, sprinkling water for curing for 7 days, and standing for curing for 28 days to obtain a high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate.

[0174] Experiment 1 According to GB / T50081-2019 "Standard for Test Methods for Physical and Mechanical Properties of Concrete", the 7-day compressive strength and 28-day compressive strength of the test samples made of the concrete mixtures prepared in each embodiment and comparative example were tested.

[0175] The specific test data of Experiment 1 are shown in Table 1.

[0176] Table 1 7-day compressive strength (MPa) 28-day compressive strength (MPa) Example 1 51.6 72.1 Example 2 52.1 72.4 Example 3 52.5 72.8 Comparative Example 1 47.1 65.3 Comparative Example 2 46.6 64.6 Comparative Example 3 47.4 65.8 Comparative Example 4 46.2 64.1 Comparative Example 5 52.3 72.5 According to the data comparison in Table 1, the compressive strength of each embodiment is close to that of Comparative Example 5. It can be seen that after each embodiment uses recycled coarse aggregate to completely replace natural stone, the strength of the prepared concrete does not decrease significantly, basically solving the strength level of concrete made of natural stone, while the compressive strength of Comparative Examples 1-4 decreases significantly. It can be seen that when the recycled coarse aggregate is modified by a modifying liquid prepared by mixing water, thioglycolic acid, octadecyltrimethylammonium chloride, and oleic acid amide propyl amine oxide, the addition of inorganic whisker filler can significantly improve the problem of many cracks in the recycled coarse aggregate, thereby improving the overall density of the concrete and restoring the strength to the level of using natural stone. When one or more of thioglycolic acid, octadecyltrimethylammonium chloride, and oleic acid amide propyl amine oxide are replaced by other modifiers, the modification effect on the recycled coarse aggregate is relatively general, and the reinforcement effect of the inorganic whisker filler on the recycled coarse aggregate decreases, resulting in a significant decrease in the strength of the concrete.

[0177] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate, characterized in that: The composition includes the following components in parts by weight: 100 parts water; Cement 185-187 parts; 30-32 parts of fly ash; Phosphorus slag 15-16 parts; 370-375 parts of fine aggregate; 730-750 parts of modified recycled coarse aggregate; 70-75 parts of inorganic whisker filler; Admixture 6.2-6.6 parts; The modified recycled coarse aggregate is prepared by soaking the recycled coarse aggregate in a modification liquid for modification; The modified liquid is a compound of water, thioglycolic acid, octadecyltrimethylammonium chloride and oleamidopropylamine oxide.

2. The high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate according to claim 1, characterized in that: In the modified liquid, the mass ratio of water, thioglycolic acid, octadecyltrimethylammonium chloride and oleamidopropylamine oxide is 100:1-2:7-8:5-6.

3. The high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate according to claim 2, characterized in that: The inorganic whisker filler is calcium carbonate whisker.

4. The high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate according to claim 3, characterized in that: The recycled coarse aggregate is made from waste concrete and has a particle size of 10-15 mm.

5. The high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate according to claim 1, characterized in that: The admixture is a compound of a water reducing agent and an early strength agent.

6. The high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate according to claim 5, characterized in that: The mass ratio of the water reducing agent to the early strength agent is 2.9-3.1:3.3-3.

5.

7. The high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate according to claim 6, characterized in that: The water reducer is a polycarboxylate water reducer.

8. The high-grade low-carbon ultra-high performance self-compacting concrete containing coarse aggregate according to claim 6, characterized in that: The early strength agent is calcium formate.