High-performance improved bamboo residue-rubber-recycled concrete and preparation method thereof

Abstract

The invention discloses high-performance improved bamboo residue-rubber-recycled concrete and a preparation method thereof, and belongs to the technical field of building materials, and the high-performance improved bamboo residue-rubber-recycled concrete is prepared from the following raw materials: 350-380 kg / m < 3 > of cement, 700-1100 kg / m < 3 > of coarse aggregate, 800-860 kg / m < 3 > of fine aggregate, 200-210 kg / m < 3 > of recycled aggregate, 15-20 kg / m < 3 > of rubber particles, 100-110 kg / m < 3 > of water, 4-6 kg / m < 3 > of a water reducing agent and improved bamboo residues. The mixing amount of the improved bamboo residues is 0.2-0.8% of the total volume of the concrete. According to the invention, the improved bamboo residues effectively play a role in fiber reinforcement in the concrete, and the recycled aggregate and the rubber particles are cooperatively utilized, so that the mechanical property and the crack resistance of the concrete are remarkably improved, high-valued utilization of various solid wastes is realized, and the concrete has excellent performance and environmental protection benefits.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new materials, and particularly relates to a high-performance improved bamboo residue-rubber-recycled concrete and a preparation method thereof. BACKGROUND

[0002] Traditional concrete mainly relies on cement, natural sand and other raw materials, and its production consumes a large amount of natural resources, and the production process of cement is accompanied by significant carbon emissions. At the same time, the high brittleness and easy cracking of traditional concrete also limit its application in some engineering fields. Developing new type of concrete with resource saving and superior performance is an important research direction in the field of building materials.

[0003] On the other hand, a large amount of solid waste is generated in the fields of construction, transportation and agriculture, such as waste concrete, waste tires and bamboo processing residues. If these wastes are not properly disposed of, they will cause environmental pollution and waste of resources. Using solid waste to prepare concrete can not only solve the problem of its disposal, but also reduce the dependence on natural resources, which has become an important way for the green development of concrete materials.

[0004] There are already researches on modifying concrete with single or two solid wastes in the prior art. For example, the incorporation of recycled aggregates will introduce weak interfaces, resulting in a decrease in the mechanical properties of concrete; the incorporation of rubber particles can improve toughness but will severely reduce strength; the incorporation of untreated plant fibers will face the problems of poor adhesion between fibers and matrix and easy decay. At present, there is still a lack of schemes that can synergistically utilize multiple solid wastes and effectively solve the key technical problems such as strength loss and interface adhesion, so as to prepare high-mechanical-property concrete. SUMMARY

[0005] The present application aims to provide a high-performance improved bamboo residue-rubber-recycled concrete and a preparation method thereof, so as to solve the technical problem of significant decrease in the mechanical properties of concrete when multiple solid wastes are synergistically utilized in the prior art.

[0006] To solve the above technical problems, the technical scheme provided by the present application is as follows: A high-performance improved bamboo residue-rubber-recycled concrete comprises the following preparation raw materials: cement 350-380 kg / m 3 , coarse aggregate 700-1100 kg / m 3 , fine aggregate 800-860 kg / m 3 , recycled aggregate 200-210 kg / m 3 , rubber particles 15-20 kg / m 3 , water 100-110 kg / m 3 , water reducing agent 4-6 kg / m 3 and improved bamboo residue. The dosage of the improved bamboo residue is 0.2-0.8% of the total volume of the concrete.

[0007] Furthermore, the fine aggregate is river sand; the coarse aggregate is crushed stone; the volume ratio of fine aggregate to rubber granules is 19:5, and the volume ratio of coarse aggregate to recycled aggregate is 3:1.

[0008] Furthermore, the fineness modulus of the river sand is 2.8, and the fine aggregate is in a dry state.

[0009] Furthermore, the rubber granules have a particle size of less than 1 mm. After being washed with a 1-3% NaOH solution, the rubber granules are rinsed with water and then air-dried.

[0010] Furthermore, the coarse aggregate is continuously graded crushed stone with a particle size of 5-30mm, and the coarse aggregate is in a dry state after being washed with water and naturally air-dried.

[0011] Furthermore, the water-reducing agent is a polycarboxylate high-efficiency water-reducing agent with a water reduction rate of 23-25%.

[0012] Furthermore, the recycled aggregate has a particle size of 5-30mm and is waste concrete with an original strength of C30.

[0013] Furthermore, the improved bamboo residue includes: thin bamboo residue with a diameter of 0.6-1.18 mm and a length of 20-40 mm; medium bamboo residue with a diameter of 1.18-2.36 mm and a length of 20-40 mm; coarse bamboo residue with a diameter of 2.36-4 mm and a length of 20-40 mm; bamboo powder and bamboo residue; bamboo chips and bamboo residue.

[0014] Furthermore, the cement is P·O42.5 silicate cement.

[0015] On the other hand, this application also claims protection for a method for preparing high-performance modified bamboo residue-rubber-recycled concrete, including the following steps: (1) Pour the coarse aggregate, fine aggregate, and recycled aggregate into a forced mixer and mix them; (2) Pour in cement, rubber granules and modified bamboo residue and mix; (3) Pour in some water and stir; (4) Pour the remaining water and water-reducing agent into the mixture and stir. After stirring, pour the mixture into a mold and vibrate it to obtain high mechanical properties bamboo residue-rubber-recycled concrete.

[0016] Furthermore, the improved method for preparing bamboo residue includes the following steps: (1) Place the raw material bamboo residue in a vibrator to remove the surface soil and some stains to obtain C1; (2) C1 is placed in a drying oven for 3 hours, and the drying time is divided into three steps, the first step is preheating, the temperature is set to 85±2 DEG C, and drying for one hour; the second step is accelerated drying, the temperature is set to 100±5 DEG C, and drying for one hour; the third step is adaptive treatment, the temperature is set to 90±5 DEG C, and drying for one hour; C2 is obtained; (3) C2 is completely placed in the improvement solution for soaking treatment, and C3 is obtained, and the improvement solution is obtained by mixing 40-45% concentration water-soluble phenolic resin and 50-55% concentration melamine-urea-phenolic resin according to 1:1 in mass; (4) C3 is placed in a drying oven for secondary drying for 2 hours, and the drying temperature is 70±5 DEG C, and C4 is obtained; (5) C4 is placed in a room for natural recovery to room temperature, and C5 is obtained; (6) C5 is screened or broken by a crusher to obtain improved bamboo residues in different forms.

[0017] Further, the independent stirring and mixing time in steps (1), (2), (3), (4) is 1-2 min.

[0018] Further, the vibration is divided into two times, the mixture is loaded into the mold for the first time, and the second time is carried out, and the vibration time is not more than 60 s.

[0019] Further, the temperature of the standard concrete curing is 20±2 DEG C, the curing humidity is greater than 95%, and the curing time is 28-32 days.

[0020] Compared with the prior art, the application has the following beneficial technical effects: The application utilizes the three solid wastes of recycled aggregate, rubber particles and bamboo residues modified by special resin to prepare a high-performance concrete. The application effectively solves the key technical problems of concrete strength reduction and poor interface adhesion caused by the mixing of multiple solid wastes. The improved bamboo residues have excellent fiber reinforcing and toughening effects, significantly improve the crack resistance and overall mechanical properties of the concrete, and realize the resource utilization of waste materials. The preparation process is simple and reliable, and provides a feasible scheme for producing environment-friendly high-strength concrete. DETAILED DESCRIPTION

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0022] Figure 1To improve the different forms of bamboo residue, from top to bottom and from left to right, they are fine rod bamboo residue, medium rod bamboo residue, thick rod bamboo residue, bamboo powder bamboo residue and bamboo chip bamboo residue in sequence; Figure 2 To be the initial form of crack development of rubber recycled concrete under axial compressive load in Example 2; Figure 3 To be the final form of crack development of rubber recycled concrete under axial compressive load in Example 2; Figure 4 To be the final form of crack development of high-performance improved bamboo residue-rubber-recycled concrete under axial compressive load in Examples 3-6, from left to right ((a)-(d)) are Examples 3-6 in sequence; Figure 5 To be the final form of crack development of high-performance improved bamboo residue-rubber-recycled concrete under axial compressive load in Examples 7-10, from left to right ((a)-(d)) are Examples 7-10 in sequence; Figure 6 To be the final form of crack development of high-performance improved bamboo residue-rubber-recycled concrete under axial compressive load in Examples 11-14, from left to right ((a)-(d)) are Examples 11-14 in sequence; Figure 7 To be the final form of crack development of high-performance improved bamboo residue-rubber-recycled concrete under axial compressive load in Examples 15-18, from left to right ((a)-(d)) are Examples 15-18 in sequence; Figure 8 To be the final form of crack development of high-performance improved bamboo residue-rubber-recycled concrete under axial compressive load in Examples 19-22, from left to right ((a)-(d)) are Examples 19-22 in sequence. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0024] Example 1: Normal concrete (NC) The normal concrete (NC) is prepared from the following raw materials: cement 360 kg / m 3 fine aggregate 855 kg / m 3 crushed stone 1034.63 kg / m 3, water 108.88 kg / m 3 , water reducing agent 4.14 kg / m 3 .

[0025] Preparation method: the fine aggregate (river sand), gravel into the forced mixer dry mixing 1 min; then add cement continue to stir 1 min; then pour into water stirring 1 min; finally add water reducing agent stirring 2 min, total mixing time 5 min. The mixture is loaded into the mold, after vibration forming, under standard curing conditions (temperature 20±2℃, humidity >95%) curing 28 days.

[0026] Example 2 Rubberized recycled concrete (RZC) Rubberized recycled concrete (RZC), prepared from the following raw materials: cement 360 kg / m 3 , fine aggregate 812.25 kg / m 3 , gravel 776 kg / m 3 , recycled aggregate 203.767 kg / m 3 , water 108.88 kg / m 3 , water reducing agent 4.14 kg / m 3 , rubber particles 19.36 kg / m 3 .

[0027] Wherein, the volume ratio of fine aggregate to rubber particles is 19:5, the volume ratio of coarse aggregate to recycled aggregate is 3:1. Rubber particles less than 1mm in size, after stirring with 2% NaOH solution for 30min, rinse with water until neutral, dry naturally and use. Recycled aggregate is waste concrete broken from the original strength C30, particle size 5-30mm.

[0028] Preparation method: according to the same procedure as example 1, batching, stirring, vibration and curing.

[0029] Example 3 High performance modified bamboo residue-rubber-recycled concrete (BRC1-0.2) A high performance modified bamboo residue-rubber-recycled concrete (BRC1-0.2), prepared from the following raw materials: cement 360 kg / m 3 , fine aggregate 812.25 kg / m 3 , gravel 776 kg / m 3 , recycled aggregate 203.767 kg / m 3 , water 108.88 kg / m 3 , water reducing agent 4.14 kg / m 3 , rubber particles 19.36 kg / m 3 , fine bamboo residue 1.8 kg / m 3; the improved bamboo residue is 0.2% of the total volume of the concrete.

[0030] The volume ratio of the fine aggregate to the rubber particles is 19:5, and the volume ratio of the coarse aggregate to the recycled aggregate is 3:1. The fine rod bamboo residue (see Figure 1 The preparation method of (a)-(e) of the application is as follows: (1) The raw material bamboo residue is placed in a vibrating machine for vibration for 5 min, and the surface soil and part of the stains are removed to obtain C1; (2) C1 is placed in a drying box for baking for 3 hours: first step of preheating, setting the temperature to 85°C for drying for 1 hour; second step of accelerated drying, setting the temperature to 100°C for drying for 1 hour; third step of adaptive treatment, setting the temperature to 90°C for drying for 1 hour; to obtain C2; (3) The dried C2 is completely immersed in the improvement solution for 2 hours to obtain C3; the improvement solution is obtained by mixing water-soluble phenolic resin with a concentration of 42% and melamine-urea-phenolic resin with a concentration of 52% at a mass ratio of 1:1; (4) C3 is placed in a drying box for secondary drying for 2 hours at a drying temperature of 70°C to obtain C4; (5) C4 is placed in a room drying and ventilated place to naturally recover to room temperature (about 25°C) to obtain C5; (6) C5 is screened by a screening machine to obtain fine rod bamboo residue with a diameter of 0.6-1.18 mm and a length of 20-40 mm.

[0031] Preparation method of high-performance improved bamboo residue-rubber-recycled concrete (BRC1-0.2): (1) The coarse aggregate (broken stone), the fine aggregate (river sand), and the recycled aggregate are poured into a forced mixer for dry mixing for 1.5 min; (2) The cement, the rubber particles, and the improved bamboo residue (fine rod bamboo residue) are poured into the mixer, and dry mixing is continued for 1.5 min; (3) 70% of water is poured in for mixing for 1.5 min; (4) The remaining 30% of water is mixed with the water reducing agent uniformly and then poured into the mixer together, and mixing is performed for 2 min, with a total mixing time of 6.5 min; (5) The mixture is loaded into a mold, and the first half is loaded for the first time of vibration, with a vibration time of 45 s; and the remaining mixture is loaded for the second time of vibration, with a vibration time of 45 s; (6) The formed test piece is cured under standard curing conditions (temperature 20±2°C, humidity >95%) for 28 days.

[0032] (The volume ratio relationship between fine aggregate, rubber particles, coarse aggregate, and recycled aggregate in the following formulation description of Examples 4-22 is consistent with Examples 2 and 3, i.e., the volume ratio of fine aggregate to rubber particles is 19:5, and the volume ratio of coarse aggregate to recycled aggregate is 3:1. For brevity, this description will not be repeated in the following examples, but the ratio relationship applies to all examples.) Example 4 High-performance modified bamboo residue-rubber-recycled concrete (BRC1-0.4) A high-performance modified bamboo residue-rubber-recycled concrete (BRC1-0.4) is prepared from the following raw materials: cement 360 kg / m 3 , fine aggregate 812.25 kg / m 3 , crushed stone 776 kg / m 3 , recycled aggregate 203.767 kg / m 3 , water 108.88 kg / m 3 , water-reducing agent 4.14 kg / m 3 , rubber particles 19.36 kg / m 3 , fine rod bamboo residue 3.6 kg / m 3 ; the modified bamboo residue content is 0.4% of the total volume of the concrete.

[0033] The method for preparing fine rod bamboo residue is the same as in Example 3.

[0034] The method for preparing recycled concrete is the same as in Example 3.

[0035] Example 5 High-performance modified bamboo residue-rubber-recycled concrete (BRC1-0.6) A high-performance modified bamboo residue-rubber-recycled concrete (BRC1-0.6) is prepared from the following raw materials: cement 360 kg / m 3 , fine aggregate 812.25 kg / m 3 , crushed stone 776 kg / m 3 , recycled aggregate 203.767 kg / m 3 , water 108.88 kg / m 3 , water-reducing agent 4.14 kg / m 3 , rubber particles 19.36 kg / m 3 , fine rod bamboo residue 5.4 kg / m 3 ; the modified bamboo residue content is 0.6% of the total volume of the concrete.

[0036] The method for preparing fine rod bamboo residue is the same as in Example 3.

[0037] The method for preparing recycled concrete is the same as in Example 3.

[0038] Example 6 High performance modified bamboo residue-rubber-recycled aggregate concrete (BRC1-0.8) A high performance modified bamboo residue-rubber-recycled aggregate concrete (BRC1-0.8) was prepared from the following raw materials: cement 360 kg / m 3 , fine aggregate 812.25 kg / m 3 , crushed stone 776 kg / m 3 , recycled aggregate 203.767 kg / m 3 , water 108.88 kg / m 3 , water reducing agent 4.14 kg / m 3 , rubber particles 19.36 kg / m 3 , fine rod bamboo residue 7.2 kg / m 3 ; the modified bamboo residue content was 0.8% of the total volume of the concrete.

[0039] The preparation method of the fine rod bamboo residue was the same as that of Example 3.

[0040] The preparation method of the recycled aggregate concrete was the same as that of Example 3.

[0041] Example 7 High performance modified bamboo residue-rubber-recycled aggregate concrete (BRC2-0.2) A high performance modified bamboo residue-rubber-recycled aggregate concrete (BRC2-0.2) was prepared from the following raw materials: cement 360 kg / m 3 , fine aggregate 812.25 kg / m 3 , crushed stone 776 kg / m 3 , recycled aggregate 203.767 kg / m 3 , water 108.88 kg / m 3 , water reducing agent 4.14 kg / m 3 , rubber particles 19.36 kg / m 3 , medium rod bamboo residue 1.8 kg / m 3 ; the modified bamboo residue content was 0.2% of the total volume of the concrete.

[0042] The preparation method of the medium rod bamboo residue was similar to that of the fine rod bamboo residue, except that in step (6), the medium rod bamboo residue with a diameter of 1.18-2.36 mm and a length of 20-40 mm was obtained by sieving.

[0043] The preparation method of the recycled aggregate concrete was the same as that of Example 3.

[0044] Example 8 High performance modified bamboo residue-rubber-recycled aggregate concrete (BRC2-0.4) A high performance modified bamboo residue-rubber-recycled aggregate concrete (BRC2-0.4) was prepared from the following raw materials: cement 360 kg / m 3Fine aggregate 812.25 kg / m 3 Crushed stone 776 kg / m 3 Recycled aggregate 203.767 kg / m 3 Water 108.88 kg / m 3 Water reducing agent 4.14 kg / m 3 Rubber particles 19.36 kg / m 3 Medium bamboo residue 3.6 kg / m 3 The modified bamboo residue content is 0.4% of the total volume of the concrete.

[0045] The medium bamboo residue was prepared according to Example 7.

[0046] The recycled concrete was prepared according to Example 3.

[0047] Example 9 High-performance modified bamboo residue-rubber-recycled concrete (BRC2-0.6) A high-performance modified bamboo residue-rubber-recycled concrete (BRC2-0.6) was prepared from the following raw materials: cement 360 kg / m 3 Fine aggregate 812.25 kg / m 3 Crushed stone 776 kg / m 3 Recycled aggregate 203.767 kg / m 3 Water 108.88 kg / m 3 Water reducing agent 4.14 kg / m 3 Rubber particles 19.36 kg / m 3 Medium bamboo residue 5.4 kg / m 3 The modified bamboo residue content is 0.6% of the total volume of the concrete.

[0048] The medium bamboo residue was prepared according to Example 7.

[0049] The recycled concrete was prepared according to Example 3.

[0050] Example 10 High-performance modified bamboo residue-rubber-recycled concrete (BRC2-0.8) A high-performance modified bamboo residue-rubber-recycled concrete (BRC2-0.8) was prepared from the following raw materials: cement 360 kg / m 3 Fine aggregate 812.25 kg / m 3 Crushed stone 776 kg / m 3 Recycled aggregate 203.767 kg / m 3 Water 108.88 kg / m 3 Water reducing agent 4.14 kg / m 3 Rubber particles 19.36 kg / m 3, medium bamboo shreds 7.2 kg / m 3 ; modified bamboo shreds 0.8% of the total volume of concrete.

[0051] Medium bamboo shreds were prepared according to the method of Example 7.

[0052] Recycled concrete was prepared according to the method of Example 3.

[0053] Example 11 High-performance modified bamboo shreds-rubber-recycled concrete (BRC3-0.2) A high-performance modified bamboo shreds-rubber-recycled concrete (BRC3-0.2) was prepared from the following raw materials: cement 360 kg / m 3 , fine aggregate 812.25 kg / m 3 , gravel 776 kg / m 3 , recycled aggregate 203.767 kg / m 3 , water 108.88 kg / m 3 , water-reducing agent 4.14 kg / m 3 , rubber particles 19.36 kg / m 3 , coarse bamboo shreds 1.8 kg / m 3 ; modified bamboo shreds 0.2% of the total volume of concrete.

[0054] Coarse bamboo shreds were prepared similarly to fine bamboo shreds, except that in step (6), the sieving resulted in coarse bamboo shreds with a diameter of 2.36-4 mm and a length of 20-40 mm.

[0055] Recycled concrete was prepared according to the method of Example 3.

[0056] Example 12 High-performance modified bamboo shreds-rubber-recycled concrete (BRC3-0.4) A high-performance modified bamboo shreds-rubber-recycled concrete (BRC3-0.4) was prepared from the following raw materials: cement 360 kg / m 3 , fine aggregate 812.25 kg / m 3 , gravel 776 kg / m 3 , recycled aggregate 203.767 kg / m 3 , water 108.88 kg / m 3 , water-reducing agent 4.14 kg / m 3 , rubber particles 19.36 kg / m 3 , coarse bamboo shreds 3.6 kg / m 3 ; modified bamboo shreds 0.4% of the total volume of concrete.

[0057] Coarse bamboo shreds were prepared according to the method of Example 11.

[0058] The method of preparing the recycled concrete is the same as that of Example 3.

[0059] Example 13 High-performance modified bamboo residue-rubber-recycled concrete (BRC3-0.6) A high-performance modified bamboo residue-rubber-recycled concrete (BRC3-0.6) is prepared from the following raw materials: cement 360 kg / m 3 , fine aggregate 812.25 kg / m 3 , gravel 776 kg / m 3 , recycled aggregate 203.767 kg / m 3 , water 108.88 kg / m 3 , water-reducing agent 4.14 kg / m 3 , rubber particles 19.36 kg / m 3 , coarse rod bamboo residue 5.4 kg / m 3 ; the modified bamboo residue content is 0.6% of the total volume of the concrete.

[0060] The method of preparing the coarse rod bamboo residue is the same as that of Example 11.

[0061] The method of preparing the recycled concrete is the same as that of Example 3.

[0062] Example 14 High-performance modified bamboo residue-rubber-recycled concrete (BRC3-0.8) A high-performance modified bamboo residue-rubber-recycled concrete (BRC3-0.8) is prepared from the following raw materials: cement 360 kg / m 3 , fine aggregate 812.25 kg / m 3 , gravel 776 kg / m 3 , recycled aggregate 203.767 kg / m 3 , water 108.88 kg / m 3 , water-reducing agent 4.14 kg / m 3 , rubber particles 19.36 kg / m 3 , coarse rod bamboo residue 7.2 kg / m 3 ; the modified bamboo residue content is 0.8% of the total volume of the concrete.

[0063] The method of preparing the coarse rod bamboo residue is the same as that of Example 11.

[0064] The method of preparing the recycled concrete is the same as that of Example 3.

[0065] Example 15 High-performance modified bamboo residue-rubber-recycled concrete (BRC4-0.2) A high-performance modified bamboo residue-rubber-recycled concrete (BRC4-0.2) is prepared from the following raw materials: cement 360 kg / m 3Fine aggregate 812.25 kg / m 3 Crushed stone 776 kg / m 3 Recycled aggregate 203.767 kg / m 3 Water 108.88 kg / m 3 Water reducing agent 4.14 kg / m 3 Rubber particles 19.36 kg / m 3 Bamboo powder 1.8 kg / m 3 The modified bamboo residue content is 0.2% of the total volume of the concrete.

[0066] The bamboo powder is prepared by the method similar to that of the fine bamboo residue, except that the bamboo powder is obtained by crushing treatment through a stirring crusher in step (6).

[0067] The recycled concrete is prepared by the method of Example 3.

[0068] Example 16 High-performance modified bamboo residue-rubber-recycled concrete (BRC4-0.4) A high-performance modified bamboo residue-rubber-recycled concrete (BRC4-0.4) is prepared from the following raw materials: cement 360 kg / m 3 Fine aggregate 812.25 kg / m 3 Crushed stone 776 kg / m 3 Recycled aggregate 203.767 kg / m 3 Water 108.88 kg / m 3 Water reducing agent 4.14 kg / m 3 Rubber particles 19.36 kg / m 3 Bamboo powder 3.6 kg / m 3 The modified bamboo residue content is 0.4% of the total volume of the concrete.

[0069] The bamboo powder is prepared by the method of Example 15.

[0070] The recycled concrete is prepared by the method of Example 3.

[0071] Example 17 High-performance modified bamboo residue-rubber-recycled concrete (BRC4-0.6) A high-performance modified bamboo residue-rubber-recycled concrete (BRC4-0.6) is prepared from the following raw materials: cement 360 kg / m 3 Fine aggregate 812.25 kg / m 3 Crushed stone 776 kg / m 3 Recycled aggregate 203.767 kg / m 3 Water 108.88 kg / m 3 Water reducing agent 4.14 kg / m3 Rubber particles 19.36 kg / m 3 Bamboo powder and residue 5.4 kg / m 3 The modified bamboo residue content is 0.6% of the total volume of the concrete.

[0072] The method of preparing the bamboo powder and residue is the same as in Example 15.

[0073] The method of preparing the recycled concrete is the same as in Example 3.

[0074] Example 18 High-performance modified bamboo residue-rubber-recycled concrete (BRC4-0.8) A high-performance modified bamboo residue-rubber-recycled concrete (BRC4-0.8) is prepared from the following raw materials: cement 360 kg / m 3 Fine aggregate 812.25 kg / m 3 Crushed stone 776 kg / m 3 Recycled aggregate 203.767 kg / m 3 Water 108.88 kg / m 3 Water reducing agent 4.14 kg / m 3 Rubber particles 19.36 kg / m 3 Bamboo powder and residue 7.2 kg / m 3 The modified bamboo residue content is 0.8% of the total volume of the concrete.

[0075] The method of preparing the bamboo powder and residue is the same as in Example 15.

[0076] The method of preparing the recycled concrete is the same as in Example 3.

[0077] Example 19 High-performance modified bamboo residue-rubber-recycled concrete (BRC5-0.2) A high-performance modified bamboo residue-rubber-recycled concrete (BRC5-0.2) is prepared from the following raw materials: cement 360 kg / m 3 Fine aggregate 812.25 kg / m 3 Crushed stone 776 kg / m 3 Recycled aggregate 203.767 kg / m 3 Water 108.88 kg / m 3 Water reducing agent 4.14 kg / m 3 Rubber particles 19.36 kg / m 3 Bamboo powder and residue 1.8 kg / m 3 The modified bamboo residue content is 0.2% of the total volume of the concrete.

[0078] The preparation method of bamboo chips and bamboo residues is similar to that of bamboo shavings and bamboo residues, except that the bamboo chips and bamboo residues are obtained by crushing treatment through a stirring crusher in step (6), and the form is slightly coarser than that of bamboo powder and bamboo residues.

[0079] The preparation method of recycled concrete is the same as that of Example 3.

[0080] Example 20 High-performance modified bamboo residue-rubber-recycled concrete (BRC5-0.4) A high-performance modified bamboo residue-rubber-recycled concrete (BRC5-0.4) is prepared from the following raw materials: cement 360 kg / m 3 , fine aggregate 812.25 kg / m 3 , gravel 776 kg / m 3 , recycled aggregate 203.767 kg / m 3 , water 108.88 kg / m 3 , water-reducing agent 4.14 kg / m 3 , rubber particles 19.36 kg / m 3 , bamboo chips and bamboo residues 3.6 kg / m 3 ; the modified bamboo residue content is 0.4% of the total volume of the concrete.

[0081] The preparation method of bamboo chips and bamboo residues is the same as that of Example 19.

[0082] The preparation method of recycled concrete is the same as that of Example 3.

[0083] Example 21 High-performance modified bamboo residue-rubber-recycled concrete (BRC5-0.6) A high-performance modified bamboo residue-rubber-recycled concrete (BRC5-0.6) is prepared from the following raw materials: cement 360 kg / m 3 , fine aggregate 812.25 kg / m 3 , gravel 776 kg / m 3 , recycled aggregate 203.767 kg / m 3 , water 108.88 kg / m 3 , water-reducing agent 4.14 kg / m 3 , rubber particles 19.36 kg / m 3 , bamboo chips and bamboo residues 5.4 kg / m 3 ; the modified bamboo residue content is 0.6% of the total volume of the concrete.

[0084] The preparation method of bamboo chips and bamboo residues is the same as that of Example 19.

[0085] The preparation method of recycled concrete is the same as that of Example 3.

[0086] Example 22 High-performance modified bamboo residue-rubber-recycled concrete (BRC5-0.8) A high-performance modified bamboo residue-rubber-recycled aggregate concrete (BRC5-0.8) is prepared from the following raw materials: cement 360 kg / m 3 fine aggregate 812.25 kg / m 3 crushed stone 776 kg / m 3 recycled aggregate 203.767 kg / m 3 water 108.88 kg / m 3 water reducing agent 4.14 kg / m 3 rubber particles 19.36 kg / m 3 bamboo residue 7.2 kg / m 3 The modified bamboo residue content is 0.8% of the total volume of the concrete.

[0087] The bamboo residue is prepared according to the method of Example 19.

[0088] The recycled aggregate concrete is prepared according to the method of Example 3.

[0089] Performance test The mechanical properties of the concrete specimens prepared in Examples 1-22 above are tested, including the cubic compressive strength, axial compressive strength, splitting tensile strength, and flexural strength tests, and the test results are shown in Table 1.

[0090] Table 1 Mechanical property test results of the concrete of each example

[0091] As can be seen from Table 1, compared with ordinary concrete (Example 1), the mechanical properties of the rubber recycled aggregate concrete (Example 2) mixed with recycled aggregate and rubber particles are all decreased, which is mainly due to the lower strength of the recycled aggregate and the poor adhesion of the rubber particles to the cement matrix. However, after mixing with the modified bamboo residue (Examples 3-22), the mechanical properties of the concrete are significantly improved, especially when the modified bamboo residue content is 0.6% (Examples 5, 9, 13, 17, 21), the strength indicators are optimized, and even some exceed those of ordinary concrete. This shows that within the content range of 0.2-0.8%, the modified bamboo residue plays a good reinforcing role in the concrete, effectively compensating for the strength loss caused by the addition of recycled aggregate and rubber particles, and 0.6% is the optimal content.

[0092] Figure 2 and Figure 3The crack development of Example 2 (rubber recycled concrete) under axial compressive load is shown. From the initial failure mode, it can be seen that the crack first occurs at the interface between the recycled aggregate and the cement paste, then rapidly expands and penetrates, forming obvious macro cracks, and finally leading to the failure of the specimen. This shows that the interface between the recycled aggregate and the cement paste is the weak link of the concrete.

[0093] Figures 4-8 The final crack development of concrete with different forms of modified bamboo residue under axial compressive load is shown. It can be seen that within the range of 0.2-0.8% of the dosage, the failure mode of concrete with modified bamboo residue has changed significantly. The crack development is more dispersed, and a large number of micro cracks appear instead of a few macro cracks. Especially at the dosage of 0.6% (Fig. (c) in the figure), the crack distribution is the most uniform, and the specimen can still maintain good integrity when it fails. This shows that within this dosage range, the modified bamboo residue plays a good bridging and crack resistance role in the concrete, effectively preventing crack propagation and improving the toughness and crack resistance of the concrete. Figures 4-8

[0094] The effects of different forms of modified bamboo residue on the performance of concrete also differ. Fine rod bamboo residue (Examples 3-6) and medium rod bamboo residue (Examples 7-10) have good reinforcing effect, especially when the dosage is 0.6%, the mechanical properties of the concrete are optimal. The reinforcing effect of coarse rod bamboo residue (Examples 11-14) is slightly worse, which may be due to the relatively small bonding area of coarse rod bamboo residue with cement matrix. The reinforcing effect of bamboo powder residue (Examples 15-18) and bamboo chip residue (Examples 19-22) is relatively weak, but it can still significantly improve the mechanical properties of rubber recycled concrete.

[0095] The present application utilizes three solid wastes, recycled aggregate, rubber particles and modified bamboo residue, in concrete, not only realizing the resource utilization of waste and reducing environmental pollution, but also preparing an environmentally friendly concrete with high mechanical properties. The modified bamboo residue is mixed at a volume fraction of 0.2-0.8%, effectively solving the problem of strength reduction caused by the addition of recycled aggregate and rubber particles, and improving the crack resistance and toughness of the concrete. The preparation method provided by the present application is simple, easy to operate and easy to realize industrial production, and has good popularization and application prospect.

[0096] ​It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; and although the present application has been described in detail with reference to the foregoing embodiments, it should be appreciated by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A high performance modified bamboo residue-rubber-recycled concrete, characterized by, The following raw materials are included in the preparation: cement 350-380 kg / m³ 3 Coarse aggregate 700-1100 kg / m³ 3 Fine aggregate 800-860kg / m³ 3 200-210 kg / m³ of recycled aggregate 3 Rubber granules 15-20 kg / m 3 Water 100-110kg / m 3 Water-reducing agent 4-6 kg / m³ 3 And modified bamboo residue; the modified bamboo residue is added at a rate of 0.2-0.8% of the total volume of concrete; the modified bamboo residue includes: fine bamboo residue with a diameter of 0.6-1.18 mm and a length of 20-40 mm; medium bamboo residue with a diameter of 1.18-2.36 mm and a length of 20-40 mm; coarse bamboo residue with a diameter of 2.36-4 mm and a length of 20-40 mm; bamboo powder and bamboo residue; bamboo chips and bamboo residue.

2. The high performance modified bamboo shot-rubber-recycled aggregate concrete according to claim 1, characterized in that, The fine aggregate is river sand; the coarse aggregate is broken stone; the volume ratio of the fine aggregate to rubber particles is 19:5, and the volume ratio of the coarse aggregate to recycled aggregate is 3:

1.

3. The high performance modified bamboo shot-rubber-recycled concrete according to claim 2, characterized in that, The fineness modulus of the river sand is 2.8, and the fine aggregate is in a dry state.

4. The high performance modified bamboo shot-rubber-recycled concrete according to claim 3, characterized in that, The particle size of the rubber particles is less than 1 mm, and the rubber particles are cleaned by stirring in a 1-3% NaOH solution and then naturally air-dried after water washing.

5. The high performance modified bamboo shot-rubber-recycled concrete according to claim 4, characterized in that, The coarse aggregate is continuously graded broken stone with a particle size of 5-30 mm, and the coarse aggregate is in a dry state after the surface is washed with water and naturally air-dried.

6. The high performance modified bamboo shot-rubber-recycled concrete according to claim 5, characterized in that, The water reducing agent is a polycarboxylic acid superplasticizer with a water reducing rate of 23-25%.

7. The high performance modified bamboo shot-rubber-recycled concrete according to claim 6, characterized in that, The recycled aggregate has a particle size of 5-30 mm and a waste concrete with an original strength of C30.

8. The high performance modified bamboo shot-rubber-recycled concrete according to claim 1, characterized in that, The cement is P·O42.5 Portland cement.

9. The method of producing high performance modified bamboo shot-rubber-recycled concrete according to any one of claims 1-8, characterized in that, The method comprises the following steps: (1) Pouring the coarse aggregate, fine aggregate, and recycled aggregate into a forced mixer for stirring; (2) Pouring the cement, rubber particles, and improved bamboo residue into the mixer for stirring; (3) Pouring part of the water into the mixer for stirring; (4) Pouring the remaining water and water reducing agent into the mixer for stirring, and then pouring the mixture into a mold for vibration to obtain bamboo residue-rubber-recycled concrete with high mechanical properties.

10. The method of claim 9, wherein, The preparation method of the improved bamboo residue comprises the following steps: (1) Placing the raw material bamboo residue in a vibrating machine to remove the soil and part of the stains on the surface to obtain C1; (2) Placing C1 in a drying box for baking for 3 hours, wherein the baking time is divided into three steps: the first step is preheating at a temperature of 85±2°C for 1 hour; the second step is accelerated drying at a temperature of 100±5°C for 1 hour; and the third step is adaptive treatment at a temperature of 90±5°C for 1 hour to obtain C2; (3) Placing the dried C2 in an improvement solution for soaking treatment to obtain C3, wherein the improvement solution is obtained by mixing water-soluble phenolic resin with a concentration of 40-45% and melamine-urea-phenolic resin with a concentration of 50-55% at a mass ratio of 1:1; (4) Placing C3 in a drying box for secondary drying for 2 hours at a drying temperature of 70±5°C to obtain C4; (5) Placing C4 in a room with ventilation for natural recovery to room temperature to obtain C5; (6) Screening or crushing C5 with a screening machine or a crushing machine to obtain improved bamboo residue with different forms.

11. The preparation method according to claim 9, characterized in that, The independent stirring and mixing time in steps (1), (2), (3), and (4) is 1-2 minutes.

12. The method of claim 10, wherein, The vibration is divided into two times, and the mixture is poured into a mold for the first time of vibration, and then the second time of vibration, wherein the vibration time is not more than 60 seconds.

13. The preparation method according to claim 11, characterized in that, The temperature for standard curing of the concrete is 20±2°C, the curing humidity is >95%, and the curing time is 28-32 days.

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