A color-changing concrete wallboard based on construction waste and preparation method thereof

Abstract

The present invention discloses a color-changing concrete wallboard based on construction waste and a preparation method thereof, and relates to the technical field of color-changing concrete wallboards, comprising a recycled concrete layer, a steel skeleton layer and a connecting steel plate layer, wherein the interior of the recycled concrete layer is wrapped with a steel skeleton layer and a connecting steel plate layer, and connecting steel plate layers are welded on both sides of the steel skeleton layer. The present invention can reduce the landfill of construction waste by preparing recycled coarse aggregate and recycled fine aggregate from construction waste, and can prepare color-changing concrete wallboards by adding photosensitive color-changing pigments and thermosensitive color-changing pigments, so as to ensure that the prepared color-changing concrete wallboards present different depths of color changes under different lighting conditions and temperature conditions, and can add a unique landscape to the exterior of the building and improve the ornamental value of the wall.

Description

Technical Field

[0001] The invention relates to the technical field of color-changing concrete wall panels, and in particular to a color-changing concrete wall panel based on construction waste and a preparation method thereof. Background Art

[0002] Color-changing concrete wall panels refer to concrete wall panels that can change color under different conditions. The color-changing wall can change color according to environmental conditions or human control, bringing unique visual effects and decorativeness to the interior space. Through its unique color-changing characteristics, it has shown significant effects in energy saving, indoor environment regulation, and aesthetics.

[0003] The defects of existing color-changing concrete wall panels are:

[0004] 1. Patent document US07681368B1 discloses a concrete composite wall panel, but the color-changing wall prepared in the above document does not use construction waste for recycling, and the color of the wall will not change due to the environment during use, and the ornamental effect is poor;

[0005] 2. Patent document US07985701B2 discloses the use of water-changing wall adhesive materials and water-changing wall adhesive materials in combination. However, in the above document, the color of the wall can only be changed by splashing water, but it cannot absorb and release heat, and cannot achieve the effect of energy saving and temperature control;

[0006] 3. Patent document JP2008037095A discloses water dispersion wall additional material and water separation wall additional material using it, but the technical problem of poor compressive and tensile resistance of the color-changing wall in the above document;

[0007] 4. Patent document CN212773244U discloses a lightweight foamed concrete exterior wall insulation decorative panel. However, the splicing positions of the concrete wall panels prepared in the above document have poor compression and tensile resistance when subjected to collisions, resulting in unstable splicing. Summary of the invention

[0008] The object of the present invention is to provide a color-changing concrete wallboard based on construction waste and a preparation method thereof, so as to solve the technical problems raised in the above-mentioned background technology.

[0009] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a color-changing concrete wallboard based on construction waste, comprising a recycled concrete layer, a steel skeleton layer and a connecting steel plate layer, wherein the interior of the recycled concrete layer is wrapped with a steel skeleton layer and a connecting steel plate layer, and connecting steel plate layers are welded on both sides of the steel skeleton layer;

[0010] The steel skeleton layer includes a plurality of vertical steel bars and a plurality of transverse steel bars, wherein the transverse steel bars are installed on the outer wall of the vertical steel bars by welding, and the vertical steel bars and the transverse steel bars are welded to form a steel skeleton layer with a grid structure, a first connecting steel plate is welded on one side of the transverse steel bar, and a plurality of groups of first connecting steel pipes are installed through the outer wall of the first connecting steel plate, a second connecting steel plate is welded on one side of the transverse steel bar, and a plurality of second connecting steel pipes are installed through the outer wall of the second connecting steel plate;

[0011] The recycled concrete layer is prepared from the following raw materials in parts by weight:

[0012] 300-360 parts of recycled coarse aggregate, 200-260 parts of recycled fine aggregate, 120-180 parts of fire-proof and crack-proof cement, 90-180 parts of water, 18-30 parts of photosensitive color-changing pigment, 19-30 parts of thermosensitive color-changing pigment, 2-5 parts of mixed fiber, 3-5 parts of foaming agent, 4-6 parts of foam stabilizer, 1-3 parts of water reducer and 7-11 parts of dispersant.

[0013] Preferably, the recycled coarse aggregate is selected from materials with a particle size of 5mm-11.5mm, and the recycled fine aggregate is selected from materials with a particle size of 2mm-4.5mm.

[0014] Preferably, the fireproof and crack-proof cement is prepared from the following raw materials in parts by weight:

[0015] 88-139 parts of cement, 18-32 parts of river sand, 42-55 parts of water, 8-13 parts of high-efficiency fireproof materials and 7-13 parts of anti-cracking additives;

[0016] The selected materials are added into a mixing mixer for mixing to obtain the required fire-proof and crack-proof cement.

[0017] Preferably, the high-efficiency fireproof material is one or more of magnesium oxide, aluminum oxide and calcium oxide, and the anti-cracking additive is one or more of fly ash, phosphorus slag powder, silicon dioxide powder or polypropylene fiber.

[0018] Preferably, the photosensitive color-changing pigment is a triphenylmethane derivative color-changing pigment, and the triphenylmethane derivative color-changing pigment is prepared by the following raw materials in parts by weight:

[0019] 12-15 parts of bromocresol purple, 2-3 parts of calcium chloride developer and 17-21 parts of cellulose diacetate solvent;

[0020] Add cellulose diacetate solvent into a mixing and heating tank, heat it to 75°C-85°C to melt the cellulose diacetate solvent, then add bromocresol purple and calcium chloride color developer into the melted solvent in the mixing and heating tank, and keep the temperature at 75°C-85°C, mix and stir for 3h-4h, and dry the mixture after the reaction is completed to obtain the desired triphenylmethane derivative color-changing pigment.

[0021] Preferably, the thermochromic pigment is crystal violet lactone thermochromic pigment, and the crystal violet lactone thermochromic pigment is prepared from the following raw materials in parts by weight:

[0022] 13-17 parts of crystal violet lactone, 1-3 parts of boric acid developer, 14-16 parts of stearic acid solvent;

[0023] Add crystal violet lactone, boric acid color developer and stearic acid solvent into a mixing and heating tank and stir and mix. The temperature during the stirring and mixing process is 60°C-80°C and the stirring and mixing time is 2.5h-3.5h. After the reaction is completed, take the mixture out of the water bath, cool it naturally to room temperature, and then dry the mixture to obtain the required crystal violet lactone thermochromic pigment.

[0024] Preferably, the mixed fiber is formed by mixing glass fiber and steel fiber, and the length of the selected glass fiber and steel fiber are both between 20 mm and 50 mm, and the diameter is between 0.2 mm and 1 mm.

[0025] Preferably, the foaming agent is one of azodicarbonamide foaming agent or polyurethane foaming agent;

[0026] The foam stabilizer is one of silicone amide, modified silicone resin polyether emulsion or dodecanol;

[0027] The water reducing agent adopts sodium methylene dimethyl dinaphthalene sulfonate polymer;

[0028] The dispersant is a phosphate dispersant or a polycarboxylic acid dispersant.

[0029] Preferably, the preparation steps of the color-changing concrete wallboard based on construction waste are as follows:

[0030] Step S1, collecting abandoned bricks, concrete blocks and other construction waste, and processing them through a crusher and a sifter to obtain recycled coarse aggregate and recycled fine aggregate that meet the requirements;

[0031] Step S2, adding 300-360 parts of recycled coarse aggregate, 200-260 parts of recycled fine aggregate, 120-180 parts of prepared fireproof and crack-proof cement, 90-180 parts of water, 18-30 parts of photosensitive color-changing pigment, 19-30 parts of thermosensitive color-changing pigment, 2-5 parts of mixed fiber, 3-5 parts of foaming agent, 4-6 parts of foam stabilizer, 1-3 parts of water reducer and 7-11 parts of dispersant into a mixing and stirring machine for mixing and stirring;

[0032] Step S3, adding the steel bar skeleton layer and the connecting steel plate layer into the mold and fixing them;

[0033] Step S4, pouring the recycled concrete slurry mixed and stirred in step S2 into a mold, and vibrating it with a vibrating rod to improve the density and strength of the wallboard;

[0034] Step S5: taking the color-changing concrete wall panel out of the mold and placing it in a curing machine for curing, thereby obtaining the prepared color-changing concrete wall panel.

[0035] Preferably, the step S1 also includes the following steps:

[0036] Step S11, the crusher is used to crush the abandoned bricks, concrete blocks and other construction waste into small particles, the screening machine is used to remove metal and plastic from the small particles, and screen out the recycled coarse aggregate with a particle size of 5mm-11.5mm and the recycled fine aggregate with a particle size of 2mm-4.5mm;

[0037] The step S2 also includes the following steps:

[0038] Step S21, the stirring speed of the mixing mixer is 130r / min-160r / min, and the stirring time is 0.5h-1h;

[0039] The step S4 also includes the following steps:

[0040] Step S41, the vibration frequency of the vibration rod is 800r / min-1200r / min;

[0041] The step S5 also includes the following steps:

[0042] Step S51, the temperature of steam curing is 85°C-95°C, and the curing time is 9h-11h.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] 1. The invention uses recycled coarse aggregate and recycled fine aggregate prepared from construction waste to reduce the landfill of construction waste. By adding photochromic pigments and thermochromic pigments to prepare color-changing concrete wall panels, it can ensure that the prepared color-changing concrete wall panels present different depths of color changes under different lighting conditions and temperature conditions, which can add a unique landscape to the appearance of the building and improve the ornamental value of the wall.

[0045] 2. The present invention can change the color of the color-changing concrete wall panels according to the external temperature to achieve the effect of absorbing or releasing heat, thereby achieving the effect of energy saving and temperature control. Under high temperature or high illumination conditions, when the color becomes obviously darker, it can more effectively absorb the heat of solar radiation and reduce the indoor temperature. When the temperature is low, the color becomes obviously lighter, which can reduce the absorption of heat and release the heat stored in the wall at the same time. Under room temperature or low illumination conditions, the wall color does not change, which helps to maintain the balance and comfort of the indoor temperature. Under medium illumination conditions, the wall color does not become obviously darker, which has a heat absorption effect, but the heat absorption is slow, thereby balancing the indoor temperature and achieving the effect of energy saving and temperature control.

[0046] 3. The present invention is conducive to improving the prepared color-changing concrete wallboard with good compressive and tensile strength by using the vertical steel bars, the transverse steel bars, the first connecting steel plate, the second connecting steel plate and the mixed fiber, thereby improving the service life of the color-changing concrete wallboard prepared by using recycled coarse aggregate and recycled fine aggregate;

[0047] 4. The present invention adds a first connecting steel plate, a first connecting steel pipe, a second connecting steel plate and a second connecting steel pipe. When two color-changing concrete wall panels prepared in the same embodiment are spliced, a fixing pipe is inserted into the second connecting steel pipe, and the first connecting steel pipe and the second connecting steel pipe are connected to each other, thereby improving the compressive and tensile resistance of the spliced ​​wall, and improving the safety and service life of the wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a schematic diagram of the three-dimensional structure of the color-changing concrete wall panel of the present invention;

[0049] Figure 2 It is a schematic diagram of the three-dimensional structure of the steel bar skeleton layer and the connecting steel plate layer of the present invention.

[0050] In the figure: 1. vertical steel bars; 2. transverse steel bars; 3. first connecting steel plate; 4. first connecting steel pipe; 5. second connecting steel plate; 6. second connecting steel pipe. DETAILED DESCRIPTION

[0051] 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.

[0052] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0053] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0054] Preparation Example 1 of fireproof and crack-proof cement: Fireproof and crack-proof cement is prepared by including the following raw materials in parts by weight:

[0055] 111 parts of cement, 26 parts of river sand, 50 parts of water, 10 parts of high-efficiency fireproof materials and 10 parts of anti-cracking additives;

[0056] The selected materials are added into a mixing mixer for mixing to obtain the required fire-proof and crack-proof cement.

[0057] Preparation Example 2 of Fireproof and Crack-Resistant Cement: Fireproof and crack-resistant cement is prepared by including the following raw materials in parts by weight:

[0058] 88 parts of cement, 32 parts of river sand, 42 parts of water, 13 parts of high-efficiency fireproof materials and 7 parts of anti-cracking additives;

[0059] The selected materials are added into a mixing mixer for mixing to obtain the required fire-proof and crack-proof cement.

[0060] Preparation Example 3 of Fireproof and Crack-Resistant Cement: Fireproof and crack-resistant cement is prepared by including the following raw materials in parts by weight:

[0061] 139 parts of cement, 18 parts of river sand, 55 parts of water, 8 parts of high-efficiency fireproof materials and 13 parts of anti-cracking additives;

[0062] The selected materials are added into a mixing mixer for mixing to obtain the required fire-proof and crack-proof cement.

[0063] Preparation Example 1 of Photosensitive Color-changing Pigment: The photosensitive color-changing pigment is a triphenylmethane derivative color-changing pigment, and the triphenylmethane derivative color-changing pigment includes the following raw materials in parts by weight:

[0064] 14 parts of bromocresol purple, 2.5 parts of calcium chloride developer and 19 parts of cellulose diacetate solvent;

[0065] Add cellulose diacetate solvent into a mixing and heating tank, heat it to 80°C to melt the cellulose diacetate solvent, then add bromocresol purple and calcium chloride color developer into the melted solvent in the mixing and heating tank, and keep the temperature at 80°C for mixing and stirring for 3.5 hours. After the reaction is completed, only dry the mixture to obtain the desired triphenylmethane derivative color-changing pigment.

[0066] Preparation Example 2 of Photosensitive Color-changing Pigment: The photosensitive color-changing pigment is a triphenylmethane derivative color-changing pigment, and the triphenylmethane derivative color-changing pigment includes the following raw materials in parts by weight:

[0067] 15 parts of bromocresol purple, 2 parts of calcium chloride developer and 21 parts of cellulose diacetate solvent;

[0068] Add cellulose diacetate solvent into a mixing and heating tank, heat to 75°C to melt the cellulose diacetate solvent, then add bromocresol purple and calcium chloride color developer into the melted solvent in the mixing and heating tank, and keep the temperature at 85°C for mixing and stirring for 3 hours. After the reaction is completed, only dry the mixture to obtain the desired triphenylmethane derivative color-changing pigment.

[0069] Preparation Example 3 of Photosensitive Color-changing Pigment: The photosensitive color-changing pigment is a triphenylmethane derivative color-changing pigment, and the triphenylmethane derivative color-changing pigment includes the following raw materials in parts by weight:

[0070] 12 parts of bromocresol purple, 3 parts of calcium chloride developer and 17 parts of cellulose diacetate solvent;

[0071] Add cellulose diacetate solvent into a mixing and heating tank, heat it to 85°C to melt the cellulose diacetate solvent, then add bromocresol purple and calcium chloride color developer into the melted solvent in the mixing and heating tank, and keep the temperature at 75°C for mixing and stirring for 4 hours. After the reaction is completed, only dry the mixture to obtain the desired triphenylmethane derivative color-changing pigment.

[0072] Preparation Example 1 of Thermochromic Pigment: The thermochromic pigment is a crystal violet lactone thermochromic pigment, which is prepared from the following raw materials in parts by weight:

[0073] 15 parts of crystal violet lactone, 2 parts of boric acid developer, 15 parts of stearic acid solvent;

[0074] Add crystal violet lactone, boric acid color developer and stearic acid solvent into a mixing and heating tank and stir and mix. The temperature during the stirring and mixing process is 70°C and the stirring and mixing time is 3 hours. After the reaction is completed, take the mixture out of the water bath, cool it naturally to room temperature, and then dry the mixture to obtain the required crystal violet lactone thermosensitive color-changing pigment.

[0075] Preparation Example 2 of Thermochromic Pigment: The thermochromic pigment is a crystal violet lactone thermochromic pigment, and the crystal violet lactone thermochromic pigment is prepared by the following raw materials in parts by weight:

[0076] 13 parts of crystal violet lactone, 3 parts of boric acid developer, 14 parts of stearic acid solvent;

[0077] Add crystal violet lactone, boric acid color developer and stearic acid solvent into a mixing and heating tank and stir and mix. The temperature during the stirring and mixing process is 80°C and the stirring and mixing time is 2.5 hours. After the reaction is completed, take the mixture out of the water bath, cool it naturally to room temperature, and then dry the mixture to obtain the required crystal violet lactone thermochromic pigment.

[0078] Preparation Example 3 of Thermochromic Pigment: The thermochromic pigment is a crystal violet lactone thermochromic pigment, which is prepared from the following raw materials in parts by weight:

[0079] 17 parts of crystal violet lactone, 1 part of boric acid developer, 16 parts of stearic acid solvent;

[0080] Add crystal violet lactone, boric acid color developer and stearic acid solvent into a mixing and heating tank and stir and mix. The temperature during the stirring and mixing process is 60°C and the stirring and mixing time is 3.5 hours. After the reaction is completed, take the mixture out of the water bath, cool it naturally to room temperature, and then dry the mixture to obtain the required crystal violet lactone thermochromic pigment.

[0081] Example 1: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: a color-changing concrete wallboard based on construction waste, comprising a recycled concrete layer, a steel skeleton layer and a connecting steel plate layer, wherein the interior of the recycled concrete layer is wrapped with the steel skeleton layer and the connecting steel plate layer, and the connecting steel plate layers are welded on both sides of the steel skeleton layer;

[0082] The steel skeleton layer includes a plurality of vertical steel bars 1 and a plurality of transverse steel bars 2, the transverse steel bars 2 are installed on the outer wall of the vertical steel bars 1 by welding, and the vertical steel bars 1 and the transverse steel bars 2 are welded to form a steel skeleton layer of a grid structure, a first connecting steel plate 3 is welded to one side of the transverse steel bar 2, and a plurality of groups of first connecting steel pipes 4 are installed through the outer wall of the first connecting steel plate 3, a second connecting steel plate 5 is welded to one side of the transverse steel bar 2, and a plurality of second connecting steel pipes 6 are installed through the outer wall of the second connecting steel plate 5;

[0083] The recycled concrete layer is prepared from the following raw materials in parts by weight:

[0084] 330 parts of recycled coarse aggregate, 230 parts of recycled fine aggregate, 150 parts of fireproof and crack-proof cement, 130 parts of water, 24 parts of photochromic pigment, 25 parts of thermochromic pigment, 4 parts of mixed fiber, 4 parts of foaming agent, 5 parts of foam stabilizer, 2 parts of water reducer and 9 parts of dispersant;

[0085] The recycled coarse aggregate should be of 5mm-11.5mm particle size, and the recycled fine aggregate should be of 2mm-4.5mm particle size.

[0086] Fire-proof and crack-proof cement is prepared using fire-proof and crack-proof cement Example 1;

[0087] The high-efficiency fireproof material is one or more of magnesium oxide, aluminum oxide and calcium oxide, and the anti-cracking additive is one or more of fly ash, phosphorus slag powder, silicon dioxide powder or polypropylene fiber;

[0088] Photochromic pigment Photochromic pigment Preparation Example 1 is used;

[0089] Thermochromic pigments are prepared using thermochromic pigments in Example 1;

[0090] The mixed fiber is made of glass fiber and steel fiber, and the length of the selected glass fiber and steel fiber is 20mm-50mm, and the diameter is 0.2mm-1mm;

[0091] The foaming agent is one of azodicarbonamide foaming agent or polyurethane foaming agent;

[0092] The foam stabilizer is one of silicone amide, modified silicone resin polyether emulsion or dodecanol;

[0093] The water reducing agent adopts sodium methylene dimethyl dinaphthalene sulfonate polymer;

[0094] The dispersant is a phosphate dispersant or a polycarboxylic acid dispersant;

[0095] The preparation steps of the color-changing concrete wallboard based on construction waste are as follows:

[0096] Step S1, collecting abandoned bricks, concrete blocks and other construction waste, and processing them through a crusher and a sifter to obtain recycled coarse aggregate and recycled fine aggregate that meet the requirements;

[0097] Step S2, add 330 parts of recycled coarse aggregate, 230 parts of recycled fine aggregate, 150 parts of prepared fireproof and crack-proof cement, 130 parts of water, 24 parts of photochromic pigment, 25 parts of thermochromic pigment, 4 parts of mixed fiber, 4 parts of foaming agent, 5 parts of foam stabilizer, 2 parts of water reducer and 9 parts of dispersant into a mixing and stirring machine for mixing and stirring;

[0098] Step S3, adding the steel bar skeleton layer and the connecting steel plate layer into the mold and fixing them;

[0099] Step S4, pouring the recycled concrete slurry mixed and stirred in step S2 into a mold, and vibrating it with a vibrating rod to improve the density and strength of the wallboard;

[0100] Step S5, taking the color-changing concrete wall panel out of the mold, and putting it into a curing machine for curing, thereby obtaining the prepared color-changing concrete wall panel;

[0101] Step S1 also includes the following steps:

[0102] Step S11, the crusher is used to crush the abandoned bricks, concrete blocks and other construction waste into small particles, the screening machine is used to remove metal and plastic from the small particles, and screen out the recycled coarse aggregate with a particle size of 5mm-11.5mm and the recycled fine aggregate with a particle size of 2mm-4.5mm;

[0103] Step S2 also includes the following steps:

[0104] Step S21, the stirring speed of the mixing mixer is 145 r / min, and the stirring time is 0.7 h;

[0105] Step S4 also includes the following steps:

[0106] Step S41, the vibration frequency of the vibration rod is 1000r / min;

[0107] Step S5 also includes the following steps:

[0108] Step S51, the temperature of steam curing is 90°C and the curing time is 10 hours.

[0109] Example 2: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of Example 1, except that: the fireproof and crack-proof cement adopts the fireproof and crack-proof cement preparation example 2;

[0110] Photochromic pigment Photochromic pigment Preparation Example 1 is used;

[0111] Thermochromic pigment Thermochromic pigment Preparation Example 1 is used.

[0112] Example 3: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as Example 1, except that: the fire-proof and crack-proof cement adopts the fire-proof and crack-proof cement preparation example 3.

[0113] Example 4: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of Example 1, except that: the photosensitive color-changing pigment adopts the photosensitive color-changing pigment preparation example 2.

[0114] Example 5: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of Example 1, except that: the fireproof and crack-proof cement adopts the fireproof and crack-proof cement preparation example 2;

[0115] Photochromic pigment Photochromic pigment Preparation Example 2 is used;

[0116] Example 6: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of Example 1, except that: the fireproof and crack-proof cement adopts the fireproof and crack-proof cement preparation example 2;

[0117] Photochromic pigment Photochromic pigment Preparation Example 2 is used;

[0118] Thermochromic pigment Thermochromic pigment Preparation Example 2 is used.

[0119] Example 7: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of Example 1, except that: the fireproof and crack-proof cement adopts the fireproof and crack-proof cement preparation example 2;

[0120] Photochromic pigment Photochromic pigment Preparation Example 3 is used;

[0121] Thermochromic pigment Thermochromic pigment Preparation Example 3 is used.

[0122] Example 8: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of Example 1, except that: the fireproof and crack-proof cement adopts the fireproof and crack-proof cement preparation example 3;

[0123] Photochromic pigment Photochromic pigment Preparation Example 3 is used;

[0124] Thermochromic Pigment Preparation Example 3

[0125] Example 9: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of Example 1, except that: the fireproof and crack-proof cement adopts the fireproof and crack-proof cement preparation example 3;

[0126] Photochromic pigment Photochromic pigment Preparation Example 2 is used;

[0127] Thermochromic pigment Thermochromic pigment Preparation Example 3 is used.

[0128] Example 10: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of Example 1, except that: the thermochromic pigment adopts the thermochromic pigment preparation example 2.

[0129] Example 11: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of embodiment 1, except that: the steel plate layers are not welded and connected on both sides of the steel bar skeleton layer.

[0130] Example 12: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of embodiment 1, except that: in step S4, the recycled concrete slurry mixed and stirred in step S2 is poured into the mold without using a vibrating rod for vibration.

[0131] Example 13: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of embodiment 1, except that: no photosensitive color-changing pigment is used.

[0132] Example 14: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of embodiment 1, except that: no thermochromic pigment is used.

[0133] Example 15: Please refer to Figure 1 and Figure 2 , an embodiment provided by the present invention: the specific implementation method is the same as that of embodiment 1, except that: a steel skeleton layer and a connecting steel plate layer are not added.

[0134] Performance Testing:

[0135] Test 1: The color-changing concrete wall panels prepared in Examples 1-14 were placed under different lighting conditions and temperature conditions to detect whether the color change on the surface of the color-changing concrete wall panels was obvious, and to determine whether the degree of the color change could adjust the ambient temperature.

[0136] Test 2: The color-changing concrete wall panels prepared in Examples 1-14 were subjected to compressive strength testing and tensile strength testing using a pressure testing machine and a tensile testing machine.

[0137] Test 3: The color-changing concrete wall panels prepared in Examples 1-14 are spliced ​​together, and the joints are tested for firmness and tensile strength. Firmness test: shake or tap the spliced ​​wall panels to check whether the connection is firm and whether there is any looseness or falling off. Tensile strength test: pull two color-changing concrete wall panels in opposite directions to check whether the connection is firm and whether there is any looseness or falling off.

[0138] Test 4: The color-changing concrete wall panels prepared in Examples 1-14 were subjected to pendulum impact. The pendulum was lifted to a certain height and then released to allow it to fall freely and hit the color-changing concrete wall panels. After 5 impacts, the wall condition of the color-changing concrete wall panels was checked.

[0139] Table 1 Test results of performance test 1

[0140]

[0141]

[0142] Furthermore, the recycled coarse aggregate and recycled fine aggregate prepared from construction waste can reduce the landfill of construction waste. By adding photochromic pigments and thermochromic pigments to prepare color-changing concrete wall panels, it can be ensured that the prepared color-changing concrete wall panels present different depths of color changes under different lighting conditions and temperature conditions, which can add a unique landscape to the appearance of the building and improve the ornamental value of the wall.

[0143] Color-changing concrete wall panels can change color according to the external temperature to absorb or release heat, thereby achieving energy-saving and temperature-control effects. Under high temperature or high illumination conditions, when the color becomes significantly darker, it can more effectively absorb the heat from solar radiation and lower the indoor temperature. When the temperature is low, the color becomes significantly lighter, which can reduce heat absorption and release the heat stored in the wall at the same time. At room temperature or low illumination, the wall color does not change, which helps maintain the balance and comfort of the indoor temperature. Under medium illumination conditions, the wall color does not become significantly darker, which has a heat-absorbing effect, but the heat absorption is slow, thereby balancing the indoor temperature and achieving energy-saving and temperature-control effects.

[0144] Table 2 Test results of performance test 2

[0145] Compressive strength test (MPa) Tensile strength test (MPa) Example 1 20.6 27.5 Example 2 21.2 28.0 Example 3 20.5 28.3 Example 4 21.3 28.0 Example 5 21.1 27.6 Example 6 21.1 27.5 Example 7 20.9 27.8 Example 8 21.0 28.3 Example 9 20.8 27.7 Example 10 20.8 27.6 Embodiment 11 20.3 27.3 Example 12 15.3 20.5 Embodiment 13 20.9 28.2 Embodiment 14 20.7 27.8 Embodiment 15 10.2 12.3

[0146] Furthermore, by using vertical steel bars 1, transverse steel bars 2, first connecting steel plates 3, second connecting steel plates 5 and mixed fibers, it is beneficial to improve the prepared color-changing concrete wall panels to have good compressive and tensile resistance, thereby improving the service life of the color-changing concrete wall panels prepared using recycled coarse aggregate and recycled fine aggregate.

[0147] Table 3 Test results of performance test 3

[0148] Firmness test Tensile strength test Example 1 Firm, no looseness, no falling off Firm, no looseness, no falling off Example 2 Firm, no looseness, no falling off Firm, no looseness, no falling off Example 3 Firm, no looseness, no falling off Firm, no looseness, no falling off Example 4 Firm, no looseness, no falling off Firm, no looseness, no falling off Example 5 Firm, no looseness, no falling off Firm, no looseness, no falling off Example 6 Firm, no looseness, no falling off Firm, no looseness, no falling off Example 7 Firm, no looseness, no falling off Firm, no looseness, no falling off Example 8 Firm, no looseness, no falling off Firm, no looseness, no falling off Example 9 Firm, no looseness, no falling off Firm, no looseness, no falling off Example 10 Firm, no looseness, no falling off Firm, no looseness, no falling off Embodiment 11 Not firm, loose, or falling off Not firm, loose, or falling off Example 12 Firm, no looseness, no falling off Firm, no looseness, no falling off Embodiment 13 Firm, no looseness, no falling off Firm, no looseness, no falling off Embodiment 14 Firm, no looseness, no falling off Firm, no looseness, no falling off Embodiment 15 Not firm, loose, or falling off Not firm, loose, or falling off

[0149] Furthermore, by adding a first connecting steel plate 3, a first connecting steel pipe 4, a second connecting steel plate 5 and a second connecting steel pipe 6, when two color-changing concrete wall panels prepared in the same embodiment are spliced, a fixing pipe is inserted into the second connecting steel pipe 6, and the first connecting steel pipe 4 and the second connecting steel pipe 6 are connected to each other, thereby improving the compressive and tensile resistance of the spliced ​​wall, and improving the safety and service life of the wall.

[0150] Table 4 Test results of performance test 4

[0151] The wall state of the discolored concrete wall panel after 5 pendulum impacts Example 1 No obvious damage to the wall Example 2 No obvious damage to the wall Example 3 No obvious damage to the wall Example 4 No obvious damage to the wall Example 5 No obvious damage to the wall Example 6 No obvious damage to the wall Example 7 No obvious damage to the wall Example 8 No obvious damage to the wall Example 9 No obvious damage to the wall Example 10 No obvious damage to the wall Embodiment 11 No obvious damage to the wall Example 12 The wall is obviously damaged and has many cracks. Embodiment 13 No obvious damage to the wall Embodiment 14 No obvious damage to the wall Embodiment 15 The wall is obviously damaged, with many cracks and broken parts.

[0152] Furthermore, the color-changing concrete wall panels prepared by adding vertical steel bars 1 and transverse steel bars 2 have good impact resistance, and when the color-changing concrete wall panels are prepared using a mold, a vibrating rod is used for vibration, which is beneficial to improving the density and strength of the wall panels.

[0153] Working principle: Recycled coarse aggregate and recycled fine aggregate prepared from construction waste can reduce the landfill of construction waste. Color-changing concrete wall panels are prepared by adding photochromic pigments and thermochromic pigments, which can ensure that the prepared color-changing concrete wall panels present different depths of color changes under different lighting conditions and temperature conditions, which can add a unique landscape to the appearance of the building and improve the ornamental value of the wall. The color-changing concrete wall panels can change color according to the external temperature to absorb or release heat, thereby achieving the effect of energy saving and temperature control. Under high temperature or high illumination conditions, when the color becomes obviously darker, it can more effectively absorb the heat from solar radiation and lower the indoor temperature. When the temperature is low, the color becomes obviously lighter, which can reduce the absorption of heat and release the heat stored in the wall at the same time. At room temperature or low illumination, the wall color does not change, which helps to maintain the balance and comfort of the indoor temperature. Under medium illumination conditions, the wall color does not become darker obviously, and it has a heat absorption effect, but the heat absorption is slow, thereby lowering the indoor temperature. The effect of energy saving and temperature control is achieved in a balanced manner. By using the vertical steel bars 1, the transverse steel bars 2, the first connecting steel plate 3, the second connecting steel plate 5 and the mixed fiber, the prepared color-changing concrete wall panels have good compressive and tensile strength, thereby improving the service life of the color-changing concrete wall panels prepared using recycled coarse aggregate and recycled fine aggregate. By adding the first connecting steel plate 3, the first connecting steel pipe 4, the second connecting steel plate 5 and the second connecting steel pipe 6, when two color-changing concrete wall panels prepared in the same embodiment are spliced, a fixed pipe is inserted into the second connecting steel pipe 6, and the first connecting steel pipe 4 and the second connecting steel pipe 6 are connected to each other, thereby improving the compressive and tensile strength of the spliced ​​wall, and improving the safety and service life of the wall. The color-changing concrete wall panels prepared by adding the vertical steel bars 1 and the transverse steel bars 2 have good impact resistance, and when the color-changing concrete wall panels are prepared using a mold, a vibrating rod is used for vibration, which is beneficial to improve the density and strength of the wall panels.

[0154] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A color-changing concrete wallboard based on construction waste, comprising a recycled concrete layer, a steel skeleton layer and a connecting steel plate layer, characterized in that: The interior of the recycled concrete layer is wrapped with a steel skeleton layer and a connecting steel plate layer, and connecting steel plate layers are welded on both sides of the steel skeleton layer; The steel skeleton layer comprises a plurality of vertical steel bars (1) and a plurality of transverse steel bars (2), wherein the transverse steel bars (2) are installed on the outer wall of the vertical steel bars (1) by welding, and the vertical steel bars (1) and the transverse steel bars (2) are welded to form a steel skeleton layer with a grid structure, a first connecting steel plate (3) is welded to one side of the transverse steel bars (2), and a plurality of first connecting steel pipes (4) are installed through the outer wall of the first connecting steel plate (3), a second connecting steel plate (5) is welded to one side of the transverse steel bars (2), and a plurality of second connecting steel pipes (6) are installed through the outer wall of the second connecting steel plate (5); The recycled concrete layer is prepared from the following raw materials in parts by weight: 300-360 parts of recycled coarse aggregate, 200-260 parts of recycled fine aggregate, 120-180 parts of fireproof and crack-proof cement, 90-180 parts of water, 18-30 parts of photochromic pigment, 19-30 parts of thermochromic pigment, 2-5 parts of mixed fiber, 3-5 parts of foaming agent, 4-6 parts of foam stabilizer, 1-3 parts of water reducer and 7-11 parts of dispersant; The fireproof and crack-proof cement is prepared from the following raw materials in parts by weight: 88-139 parts of cement, 18-32 parts of river sand, 42-55 parts of water, 8-13 parts of high-efficiency fireproof materials and 7-13 parts of anti-cracking additives; Add the selected materials into a mixing mixer and mix them to obtain the required fire-proof and crack-proof cement; The photosensitive color-changing pigment is a triphenylmethane derivative color-changing pigment, and the triphenylmethane derivative color-changing pigment includes the following raw materials in parts by weight: 12-15 parts of bromocresol purple, 2-3 parts of calcium chloride developer and 17-21 parts of cellulose diacetate solvent; Adding cellulose diacetate solvent into a mixing and heating tank, heating to 75°C-85°C to melt the cellulose diacetate solvent, then adding bromocresol purple and calcium chloride color developer into the melted solvent in the mixing and heating tank, and maintaining the temperature at 75°C-85°C, mixing and stirring for 3h-4h, and drying the reaction-completed mixture to obtain the desired triphenylmethane derivative color-changing pigment; The thermochromic pigment is a crystal violet lactone thermochromic pigment, and the crystal violet lactone thermochromic pigment is prepared from the following raw materials in parts by weight: 13-17 parts of crystal violet lactone, 1-3 parts of boric acid developer, 14-16 parts of stearic acid solvent; Add crystal violet lactone, boric acid color developer and stearic acid solvent into a mixing and heating tank and stir and mix. The temperature during the stirring and mixing process is 60°C-80°C and the stirring and mixing time is 2.5h-3.5h. After the reaction is completed, take the mixture out of the water bath, cool it naturally to room temperature, and then dry the mixture to obtain the required crystal violet lactone thermochromic pigment.

2. The color-changing concrete wallboard based on construction waste according to claim 1 is characterized in that: The recycled coarse aggregate is selected from materials with a particle size of 5mm-11.5mm, and the recycled fine aggregate is selected from materials with a particle size of 2mm-4.5mm.

3. The color-changing concrete wallboard based on construction waste according to claim 1 is characterized in that: The high-efficiency fireproof material is one or more of magnesium oxide, aluminum oxide and calcium oxide, and the anti-cracking additive is one or more of fly ash, phosphorus slag powder, silicon dioxide powder or polypropylene fiber.

4. The color-changing concrete wallboard based on construction waste according to claim 1, characterized in that: The mixed fiber is made of glass fiber and steel fiber, and the length of the selected glass fiber and steel fiber are both between 20mm and 50mm, and the diameter is between 0.2mm and 1mm.

5. The color-changing concrete wallboard based on construction waste according to claim 1, characterized in that: The foaming agent is one of azodicarbonamide foaming agent or polyurethane foaming agent; The foam stabilizer is one of silicone amide, modified silicone resin polyether emulsion or dodecanol; The water reducing agent adopts sodium methylene dimethyl dinaphthalene sulfonate polymer; The dispersant is a phosphate dispersant or a polycarboxylic acid dispersant.

6. A method for preparing a color-changing concrete wallboard based on construction waste according to any one of claims 1 to 5, characterized in that: The preparation steps of the color-changing concrete wallboard based on construction waste are as follows: Step S1, collecting abandoned bricks, stones, concrete blocks and construction waste, and processing them with a crusher and a sifter to obtain recycled coarse aggregate and recycled fine aggregate that meet the requirements; Step S2, adding 300-360 parts of recycled coarse aggregate, 200-260 parts of recycled fine aggregate, 120-180 parts of prepared fireproof and crack-proof cement, 90-180 parts of water, 18-30 parts of photosensitive color-changing pigment, 19-30 parts of thermosensitive color-changing pigment, 2-5 parts of mixed fiber, 3-5 parts of foaming agent, 4-6 parts of foam stabilizer, 1-3 parts of water reducer and 7-11 parts of dispersant into a mixing and stirring machine for mixing and stirring; Step S3, adding the steel bar skeleton layer and the connecting steel plate layer into the mold and fixing them; Step S4, pouring the recycled concrete slurry mixed and stirred in step S2 into a mold, and vibrating it with a vibrating rod to improve the density and strength of the wallboard; Step S5: taking the color-changing concrete wall panel out of the mold and placing it in a curing machine for curing, thereby obtaining the prepared color-changing concrete wall panel.

7. The method for preparing a color-changing concrete wallboard based on construction waste according to claim 6, characterized in that: The step S1 also includes the following steps: Step S11, the crusher is used to crush the abandoned bricks, stones, concrete blocks and construction waste into small particles, the screening machine is used to remove metal and plastic from the small particles, and screen out recycled coarse aggregate with a particle size of 5mm-11.5mm and recycled fine aggregate with a particle size of 2mm-4.5mm; The step S2 also includes the following steps: Step S21, the stirring speed of the mixing mixer is 130r / min-160r / min, and the stirring time is 0.5h-1h; The step S4 also includes the following steps: Step S41, the vibration frequency of the vibration rod is 800r / min-1200r / min; The step S5 also includes the following steps: Step S51, the temperature of steam curing is 85°C-95°C, and the curing time is 9h-11h.

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