Preparation method of mortar screeding strip

Abstract

The invention relates to the technical field of building screeding strips, in particular to a preparation method of a mortar screeding strip, the performance and forming quality of the screeding strip are remarkably improved by scientifically optimizing a mortar formula and combining a systematic preparation process, and a composite cementing material combination is adopted in the formula and comprises PO 52.5 cement and aluminate cement, the early strength and final strength are guaranteed through synergistic hydration reaction, the problems that traditional mortar is long in maintenance period and slow in strength increase are solved, meanwhile, sodium carbonate, calcium formate and other functional admixtures are added, the mortar setting time and early strength development are effectively regulated and controlled, ribs can have the demolding strength within 2 hours, corner collapse and deformation are avoided after demolding, and the quality of the ribs is improved. The production efficiency and operation safety are improved, PP fibers and wood fibers are adopted for double toughening, the crack resistance and toughness of ribs are improved, and the impact resistance and edge stability of mortar are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of building screeding bars, and particularly to a preparation method for mortar screeding bars. Background Art

[0002] With the rapid development of urban and rural construction industries in China and the continuous improvement of people's living standards, residents' requirements for housing conditions have gradually shifted from "having a place to live" to "living well, beautifully, and comfortably". Especially during modern indoor and outdoor decoration, as an important visible surface of a building, the flatness, aesthetics, and construction efficiency of the wall surface have all become important criteria for measuring the quality of a project. Therefore, in wall construction, especially in plastering and leveling operations, the screeding construction process is widely used to meet the high-standard and high-quality building decoration requirements.

[0003] During traditional plastering, construction workers often manually adjust the thickness of the mortar based on experience, which is extremely likely to cause uneven wall surfaces, large errors, and a high rework rate. The introduction of screeding bars effectively standardizes the construction reference line. By pre-laying screeding bars, clear and unified elevation references and positioning references are formed on the wall surface. Construction workers perform large-area plastering operations based on this, which not only improves the overall flatness and perpendicularity of the wall surface but also significantly enhances the construction efficiency and consistency. Therefore, the use of screeding bars has become an indispensable standardized auxiliary material in modern building decoration construction.

[0004] However, most of the existing screeding bars on the market are finished components or temporarily hand-made on the construction site, with many problems such as inconsistent dimensions, unstable quality, rough surfaces, low forming efficiency, and waste of raw materials. At the same time, some production methods are highly dependent on the operating environment and require a high technical level of operators, making it difficult to achieve large-scale and rapid production, which restricts the standardization and industrialization development of the process. Therefore, developing a preparation method for screeding bars that is easy to operate, has high forming efficiency, uniform dimensions, stable performance, and is suitable for large-scale construction sites has important engineering practical value and broad market prospects.

[0005] In view of the above situation, in order to overcome the above technical problems, the present invention designs a preparation method for mortar screeding bars to solve the above technical problems. Summary of the Invention

[0006] The technical objective to be achieved by the present invention is: The present invention provides a new preparation method for screeding bars. By optimizing the formulation, process flow, and mold structure design, the standardized and batch production of screeding bars is realized, while taking into account the construction strength, forming accuracy, and environmental protection performance, providing a more efficient and reliable solution for wall surface leveling construction in the building industry.

[0007] To achieve the above technical objective, the present invention provides the following technical solutions:

[0008] A method for preparing mortar screeding bars, the steps of the method are as follows:

[0009] S1: Weigh the mortar for making screeding bars that has been pre-stirred evenly, and fully mix it evenly through mechanical equipment in the early stage;

[0010] S2: Add clean water into a container, and start low-speed stirring using a stirring device; during the continuous stirring process, slowly pour the weighed mortar into the water to make it fully blend with the clean water, and control the stirring time between 3 and 5 minutes to ensure the uniformity and appropriate fluidity of the mortar;

[0011] S3: After stirring is completed, judge the state of the mortar to ensure that it reaches an appropriate fluidity (the fluidity value is about 180 mm), so as to ensure that it is easy to be injected into the resin mold and formed subsequently;

[0012] S4: Pour the mixed mortar into the resin mold. The resin mold can form 20 to 25 screeding bars at one time. During the grouting process, continuity and stability should be maintained to avoid entraining air bubbles or interruption;

[0013] S5: When the mortar fills the resin mold, use an aluminum alloy trowel with a length of 0.8 m to scrape off the excess mortar along the parallel direction of the mold surface to make the surface smooth and flat and maintain a consistent height, so as to form a unified size;

[0014] S6: Let the filled mold stand for 2 hours to make it naturally harden. During this period, vibration and external force interference should be avoided. When the mortar is completely hardened and the strength reaches more than 10 MPa, the demolding operation can be carried out. When demolding, careful operation should be taken to prevent damage to the screeding bars or breakage of the edges and corners;

[0015] S7: The demolded screeding bars are stacked at the designated position according to the predetermined specifications for natural curing. The curing period is about 10 days. During this period, keep the environment ventilated, avoid direct sunlight and rain erosion to ensure the stable performance and long service life of the screeding bars.

[0016] The component ratio of the mortar is as follows:

[0017] po52.5 cement: 200 parts - 300 parts,

[0018] Aluminate cement: 100 parts - 150 parts,

[0019] Powder polycarboxylate water reducer: 1 part - 2 parts,

[0020] Reinforcing agent: 5 parts - 8 parts,

[0021] Setting regulator: 10 parts,

[0022] Toughening agent: 10 parts,

[0023] Toughening agent: 5 parts,

[0024] Thickener: 0.5 parts,

[0025] Fine sand with a diameter value of less than 1.0 mm: 550 - 700 parts,

[0026] Water: 400 - 450 parts.

[0027] The strengthening agent includes sodium carbonate. As an early - strength strengthening agent, sodium carbonate can stimulate the hydration reaction of cement, accelerate the growth of early strength, shorten the demolding time, improve the compressive strength of the screeding bar within 1 - 2 days, and enhance the construction efficiency. It is especially suitable for fast - paced construction scenarios.

[0028] The setting regulator includes calcium formate. Calcium formate can effectively promote the hydration reaction of cement under low - temperature conditions, improve the early hardening characteristics of the mortar, and at the same time has a certain retarding effect, prolonging the constructible time. It achieves the balance between early strength and retarding, facilitating the operation of workers and being beneficial to early shaping, and improving the construction adaptability.

[0029] The toughening agent includes PP fibers. The PP fibers form a three - dimensional distribution structure in the mortar, preventing the expansion of micro - cracks, enhancing the crack resistance and toughness, significantly reducing shrinkage cracks, improving the stability of the bar during drying or shrinking, and enhancing the impact resistance and durability.

[0030] The toughening agent includes wood fibers. Wood fibers have good water retention and flexibility, can improve the internal structure of the mortar and provide secondary support. Cooperating with PP fibers for double toughening, the bar is more fracture - resistant after demolding, not easily chipped at the corners, and the finished product rate is improved.

[0031] The thickener includes hydroxycellulose. Hydroxycellulose can enhance the thixotropy and water retention of the mortar, improve the construction performance, prevent bleeding better, have better slurry - hanging performance, make the mortar injection smoother, the formed corners fuller, and at the same time extend the open time and improve the troweling effect.

[0032] Before injecting mortar into the mold, the inner wall of the mold needs to be pretreated first. One of the key processes is to spray a release agent to prevent the mortar from sticking to the mold during the hardening process. In specific operations, a layer of release agent with a thickness of 0.3 to 0.5 mm is evenly coated using a spray gun or brush. Environmentally friendly water-based paraffin emulsion or polyurethane emulsion is recommended. The release agent has good heat resistance, lubrication, and isolation properties. It can not only effectively prevent the mortar from sticking to the mold, ensuring the surface of the formed rib is complete and smooth, but also significantly reduce the resistance during the demolding process, reducing the manual operation difficulty and mold wear. In addition, after spraying, it needs to be left standing for 5 to 10 minutes to form a dense isolation film to ensure its complete fit with the mold. This can significantly improve the demolding efficiency, especially suitable for batch production operations, avoiding quality problems such as cracking and defects at the edges and corners of the ribs caused by unsmooth demolding, thereby improving the qualified rate of finished products and the overall construction quality.

[0033] After the mortar is injected into the mold, in order to ensure that the mortar is evenly distributed and has a compact structure in the mold cavity, an auxiliary vibrating operation needs to be carried out using a vibrating table. The working frequency of the vibrating table should be controlled between 50 and 60 Hz, and the vibration duration is recommended to be set at 30 to 45 seconds. During the vibration process, the air bubbles in the mortar will be effectively discharged, thereby reducing the holes and inclusions inside the ribs and improving the density and strength. In addition, vibration can also promote the mortar to flow fully along the corners of the mold, making the edges of the ribs more plump and avoiding quality problems such as peeling and hollowing. This vibrating compaction process plays a significant role in improving the compressive and flexural properties and surface flatness of the punching ribs. Especially in the batch production scenario, reasonable vibration settings can maintain the performance consistency of each batch of ribs, effectively avoiding quality fluctuations caused by manual vibration errors, and is a key link to achieve the standardized and high-quality forming of ribs.

[0034] After the mortar injection into the mold is completed and the initial vibration compaction is carried out, a trowel is needed to scrape off the excess mortar on the surface of the mold. During the operation, the trowel should be kept at an inclined angle of about 45 degrees and slowly scraped longitudinally from one end of the mold to the other end, repeating twice to ensure that the top of each rib is flat and consistent. This angle can effectively control the scraping depth, avoiding scraping off too much mortar and affecting the forming thickness, and also preventing residual high points from affecting the plastering reference. During the operation, it is recommended to use an aluminum alloy trowel with light weight and strong rigidity to obtain better control and wear resistance. The mortar scraped off each time should be promptly recovered into the mixing bucket for remixing to avoid waste, which is beneficial to improving the material utilization rate and economy. This mortar scraping process is crucial for the height consistency and surface flatness of the ribs, and can effectively reduce the subsequent wall leveling error, improving the quality and efficiency of the overall decorative construction.

[0035] After the mortar is formed, the screed bar is not considered complete after demolding. Its final performance depends on a scientific and reasonable curing process. Especially within the initial 48 hours, effective wet curing treatment must be carried out to control the rate of the cement hydration reaction and prevent early cracking. It is recommended to cover the surface of the screed bar with wet burlap or plastic film. The covering material should fit the screed bar and retain moisture to avoid direct contact with air, which may cause surface shrinkage. During the covering period, at least two spray humidification operations should be carried out daily to keep the surface always moist, thus delaying water evaporation and ensuring sufficient cement hydration reaction. Good initial curing can not only improve the overall strength, crack resistance and durability of the screed bar, but also avoid potential wall surface cracking problems caused by surface microcracks in the later stage. It is an important technological measure to ensure the long-term stability of the screed bar.

[0036] In the actual construction process, to ensure the overall coordination and aesthetics after the wall decoration is completed, the color consistency of the screed bar is also particularly important. Therefore, during the mortar mixing stage, no more than 1% of inorganic gray pigment can be added to the raw materials. Mineral pigments with strong stability such as iron oxide powder or manganese oxide powder are recommended. After the pigment is added, it must be fully stirred to ensure its uniform distribution throughout the mortar, so as to achieve consistent color of the screed bar without color difference or stratification. Inorganic pigments have good ultraviolet resistance, are not easy to fade, and do not affect the physical strength and construction performance of the mortar itself. The screed bar made in this way has stable color and uniform texture, can better integrate with the subsequent plastering layer, and is especially suitable for decorative projects with high appearance requirements.

[0037] To ensure the dimensional stability, smooth demolding and improved forming efficiency of the screed bar, the mold structure adopted in the present invention is specially designed. The mold is provided with precise positioning pins and end limit devices, which can ensure that the length error of each screed bar is controlled within ±2 mm, guaranteeing the accuracy of the construction reference line. At the same time, the overall mold adopts a flip structure design. After the grouting and vibration compaction are completed, convenient demolding can be achieved through the flipping operation, reducing manual intervention and operation fatigue. In addition, this structure is also convenient for cleaning and maintenance, suitable for repeated use many times, and prolongs the service life of the mold. After the structure is optimized, not only the forming accuracy of the screed bar is improved, but also the production efficiency and the standardization level of on-site construction are significantly increased, which is suitable for popularization in large-scale production scenarios.

[0038] To ensure the best strength development effect of the screeding bar during the curing process, the environmental conditions must be strictly controlled. It is recommended that the curing humidity be maintained above 60%. Too low humidity will cause the surface layer of the mortar to crack rapidly, affecting the structural compactness; while the curing temperature should be controlled between 18°C and 30°C. Too high temperature will accelerate water evaporation and inhibit cement hydration, and too low temperature will slow down the reaction rate and prolong the curing cycle. Under suitable environmental conditions, components such as cement, strengthening agent, and setting regulator in the mortar can play a balanced role, making the internal structure of the screeding bar more stable, forming continuous and dense hydration products, and improving its ultimate strength, crack resistance, and durability. Standardized environmental curing control not only improves the qualified rate of finished products but also is the key guarantee for quality consistency in large-scale production.

[0039] The beneficial effects of the present invention are as follows:

[0040] (1) By scientifically optimizing the mortar formula and combining a systematic preparation process, the present invention significantly improves the performance and molding quality of the screeding bar. The composite cementitious material combination, including PO 52.5 cement and aluminate cement, is adopted in its formula to achieve dual guarantees of early strength and final strength through synergistic hydration reactions, solving the problems of long curing cycle and slow strength growth of traditional mortar. At the same time, functional admixtures such as sodium carbonate and calcium formate are added to effectively regulate the setting time and early strength development of the mortar, enabling the screeding bar to have demolding strength within 2 hours. After demolding, it does not break at the corners or deform, improving production efficiency and operation safety. The double toughening with PP fiber and wood fiber not only improves the crack resistance and toughness of the screeding bar but also significantly improves the impact resistance and edge stability of the mortar, meeting the complex transportation and installation requirements at the construction site. Hydroxycellulose, as a thickening and water-retaining agent, improves the construction performance of the mortar, ensuring full injection into the mold, smooth plastering, and no bleeding, fundamentally solving the problems of easy hollowing and warping of traditional screeding bars during pouring or curing.

[0041] (2) The present invention also demonstrates high practicality and standardization advantages in terms of process design. Through the settings of mold release agent spraying and anti-sticking bonding, the demolding efficiency and the surface integrity of the rib are improved, and the damage caused by manual knocking is avoided. The vibrator is used to compact the injected mortar, effectively removing air bubbles, enhancing the density and the final compressive strength, making the surface of the rib smoother and more accurate as a leveling reference. At the same time, the forming mold structure uses positioning pins and limit devices to control dimensional errors, achieving highly consistent rib lengths and thicknesses, and improving the wall construction accuracy. During the natural curing process, early hydration is controlled by covering with wet linen and periodic humidification, avoiding dry shrinkage cracks, ensuring a steady increase in strength, and cooperating with the humidity and temperature control schemes to ensure the adaptability and reliability of the finished product during construction in different seasons. In addition, to enhance the integrated decoration effect, inorganic pigments are reasonably added to the mortar, achieving a surface effect with consistent color and no fading, meeting the requirements of modern architecture that emphasizes both aesthetics and functionality. Therefore, the present invention not only improves the performance and reliability of the rib, but also optimizes the production process and construction adaptability, having significant practical value and promotion prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0043] Now the above and other aspects of the present invention will be described by way of example only with reference to the drawings, where:

[0044] Figure 1 is a schematic flow chart of the method of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] In order to better understand the above technical solutions, the following will describe the above technical solutions in detail in conjunction with the drawings of the specification and specific embodiments.

[0046] As Figure 1 shown, a method for preparing a mortar screeding rib, the steps of the method are as follows:

[0047] S1: Weigh the mortar for making the rib that has been pre-stirred evenly, and fully mix it evenly in advance through mechanical equipment;

[0048] S2: Add clean water to the container, and at the same time start low-speed stirring using a stirring device; during the continuous stirring process, slowly pour the weighed mortar into the water to make it fully blend with the clean water, and control the stirring time between 3 and 5 minutes to ensure the uniformity and appropriate fluidity of the mortar;

[0049] S3: After the stirring is completed, judge the state of the mortar to ensure that it reaches an appropriate fluidity (the fluidity value is about 180 mm), so as to ensure that it is easy to be injected into the resin mold and molded subsequently;

[0050] S4: Pour the mixed mortar into the resin mold. The resin mold can form 20 to 25 screeding bars at one time. During the grouting process, continuity and stability should be maintained to avoid entraining air bubbles or interruption;

[0051] S5: When the mortar fills the resin mold, use an aluminum alloy trowel with a length of 0.8 m to scrape off the excess mortar along the parallel direction of the mold surface to make the surface smooth and flat and maintain a consistent height, so as to form a unified size;

[0052] S6: Let the filled mold stand for 2 hours to harden naturally. During this period, vibration and external force interference should be avoided. When the mortar is completely hardened and the strength reaches more than 10 MPa, the demolding operation can be carried out. Care should be taken during demolding to prevent damage to the screeding bars or breakage of the corners;

[0053] S7: The demolded screeding bars are stacked at the designated position according to the predetermined specifications for natural curing. The curing period is about 10 days. During this period, keep the environment ventilated, avoid direct sunlight and rain erosion to ensure the stable performance and long service life of the screeding bars.

[0054] The component ratio of the said mortar is as follows:

[0055] po52.5 cement: 200 parts - 300 parts,

[0056] Aluminate cement: 100 parts - 150 parts,

[0057] Powder polycarboxylate water reducer: 1 part - 2 parts,

[0058] Reinforcing agent: 5 parts - 8 parts,

[0059] Setting regulator: 10 parts,

[0060] Toughening agent: 10 parts,

[0061] Toughening agent: 5 parts, thickening agent: 0.5 part,

[0062] Fine sand with a diameter value of less than 1.0 mm: 550 parts - 700 parts, water: 400 - 450 parts.

[0063] The following is a parameter comparison table of traditional screeding bars and screeding bars manufactured by this method:

[0064]

[0065]

[0066] The reinforcing agent includes sodium carbonate. As an early-strength reinforcing agent, sodium carbonate can stimulate the hydration reaction of cement, accelerate the growth of early strength, shorten the demolding time, improve the compressive strength of the screed bar within 1 - 2 days, and enhance the construction efficiency. It is especially suitable for fast-paced construction scenarios.

[0067] The setting regulator includes calcium formate. Calcium formate can effectively promote the hydration reaction of cement under low-temperature conditions, improve the early hardening characteristics of the mortar, and at the same time has a certain retarding effect, prolonging the workable time. It realizes the balance between early strength and retarding, facilitating the operation of workers and being beneficial to early shaping, and improving the construction adaptability.

[0068] The toughening agent includes PP fibers. The PP fibers form a three-dimensional distribution structure in the mortar, preventing the expansion of microcracks, enhancing the crack resistance and toughness, significantly reducing dry shrinkage cracks, improving the stability of the bar during drying or shrinking, and enhancing the impact resistance and durability.

[0069] The toughening agent includes wood fibers. Wood fibers have good water retention and flexibility, can improve the internal structure of the mortar and provide secondary support. Cooperating with PP fibers for double toughening, the bar is more fracture-resistant and less likely to break at the corners after demolding, improving the finished product rate.

[0070] The thickening agent includes hydroxycellulose. Hydroxycellulose can enhance the thixotropy and water retention of the mortar, improving the construction performance. It has better water bleeding and slurry hanging prevention performance, making the mortar injection into the mold smoother and the formed corners more plump. At the same time, it prolongs the open time and improves the scraping effect.

[0071] Before injecting the mortar into the mold, the inner wall of the mold needs to be pretreated first. One of the key processes is to spray a release agent to prevent the mortar from sticking to the mold during the hardening process. In specific operations, a layer of release agent with a thickness of 0.3 to 0.5 mm is evenly coated using a spray gun or brush. It is recommended to use an environmentally friendly water-based paraffin emulsion or polyurethane emulsion. The release agent has good heat resistance, lubrication and isolation properties. It can not only effectively prevent the mortar from sticking to the mold, ensuring the surface of the formed bar is complete and smooth, but also significantly reduce the resistance during the demolding process, reducing the manual operation difficulty and mold loss. In addition, after spraying, it needs to be left standing for 5 to 10 minutes to form a dense isolation film to ensure its complete adhesion to the mold. This can significantly improve the demolding efficiency, especially suitable for batch production operations, avoiding quality problems such as corner cracking and defects of the bar caused by unsmooth demolding, and thus improving the finished product qualification rate and overall construction quality.

[0072] After the mortar is injected into the mold, in order to ensure that the mortar is evenly distributed and tightly structured in the mold cavity, a vibrating table is required for auxiliary compaction operations. The working frequency of the vibrating table should be controlled between 50 and 60 Hz, and the vibration duration is recommended to be set at 30 to 45 seconds. During the vibration process, air bubbles in the mortar will be effectively discharged, thereby reducing holes and inclusions inside the rib, and improving the density and strength. In addition, vibration can also promote the full flow of the mortar along the corners of the mold, making the edges of the rib more plump, and avoiding quality problems such as peeling and hollowing. This compaction process plays a significant role in improving the compressive and flexural properties and surface flatness of the rib. Especially in the mass production scenario, reasonable vibration settings can maintain the performance consistency of each batch of ribs, effectively avoiding quality fluctuations caused by manual vibration errors, and is a key link to achieve the standardized and high-quality forming of the ribs.

[0073] After the mortar injection into the mold is completed and preliminary compaction is carried out, a trowel is needed to scrape off the excess mortar on the mold surface. During the operation, the trowel should be kept at an inclined angle of about 45 degrees and slowly scraped longitudinally from one end of the mold to the other end, repeating twice to ensure that the top of each rib is flat and consistent. This angle can effectively control the scraping depth, avoiding scraping off too much mortar and affecting the forming thickness, and also preventing residual high points from affecting the plastering reference. During the operation, it is recommended to use an aluminum alloy trowel with light material and strong rigidity to obtain better control and wear resistance. The mortar scraped off each time should be promptly recycled into the mixing bucket for remixing to avoid waste, which is beneficial to improving the material utilization rate and economy. This mortar scraping process is crucial for the height consistency and surface flatness of the rib, which can effectively reduce the subsequent wall leveling error and improve the quality and efficiency of the overall decorative construction.

[0074] The rib formed by the mortar is not considered complete after demolding. Its final performance formation depends on a scientific and reasonable curing process. Especially within the initial 48 hours, effective wet curing treatment must be carried out to control the progress speed of the cement hydration reaction and prevent early cracking. It is recommended to cover the surface of the rib with wet burlap or plastic film. The covering material should fit the rib and retain humidity, avoiding direct contact with air and causing surface shrinkage. During the covering period, at least two spray humidification operations should be carried out daily to keep the surface always in a wet state, thereby delaying water evaporation and ensuring the full hydration reaction of the cement. Good initial curing can not only improve the overall strength, crack resistance and durability of the rib, but also avoid potential wall cracking hazards caused by surface microcracks in the later stage, which is an important technological measure to ensure the long-term stability of the rib.

[0075] During the actual construction process, to ensure the overall coordination and aesthetics after the wall decoration is completed, the color consistency of the screeding bars is also particularly important. For this purpose, during the mortar mixing stage, an inorganic gray pigment not exceeding 1% can be added to the raw materials. Mineral colorants with strong stability such as iron oxide powder or manganese oxide powder are recommended. After the pigment is added, it must be fully stirred evenly to ensure its uniform distribution throughout the mortar, so as to achieve consistent colors of the bars without color difference or stratification. Inorganic pigments have good ultraviolet resistance, are not easy to fade, and do not affect the physical strength and construction performance of the mortar itself. The bars made in this way have stable colors and uniform textures, can better integrate with the subsequent plastering layer, and are especially suitable for decorative projects with high requirements for appearance.

[0076] To ensure the stable size, smooth demolding and improved forming efficiency of the screeding bars, the mold structure adopted in the present invention is specially designed. The mold is provided with precise positioning pins and end limit devices, which can ensure that the length error of each bar is controlled within ±2 mm, guaranteeing the accuracy of the construction reference line. At the same time, the overall mold adopts a flip structure design. After the grouting and vibration compaction are completed, convenient demolding can be achieved through the flip operation, reducing manual intervention and operation fatigue. In addition, this structure is also convenient for cleaning and maintenance, suitable for repeated use, and prolongs the service life of the mold. After the structure optimization, not only the forming accuracy of the bars is improved, but also the production efficiency and the standardization level of on-site construction are significantly increased, which is suitable for popularization in large-scale production scenarios.

[0077] To ensure the best strength development effect of the screeding bars during the curing process, the environmental conditions must be strictly controlled. It is recommended that the curing humidity be maintained above 60%. Too low humidity will cause the surface layer of the mortar to crack rapidly, affecting the structural compactness; while the curing temperature should be controlled between 18°C and 30°C. Too high temperature will accelerate the evaporation of water, inhibit the hydration of cement, and too low temperature will slow down the reaction rate and prolong the curing period. Under suitable environmental conditions, components such as cement, strengthening agent, and setting regulator in the mortar can play a balanced role, making the internal structure of the screeding bars more stable, forming continuous and dense hydration products, and improving its ultimate strength, crack resistance and durability. Standardized environmental curing control not only improves the qualified rate of finished products, but also is the key guarantee for quality consistency in the large-scale production process.

[0078] Various modifications to the present disclosure will be apparent to those of ordinary skill in the art, and the general principles defined herein can be applied to other variations without departing from the scope of the present disclosure. Thus, the present disclosure is not limited to the examples and designs described herein, but should be accorded the widest scope consistent with the principles and novel features disclosed herein. Although one or more exemplary embodiments of the present disclosure have been described with reference to the accompanying drawings, those of ordinary skill in the art will understand that various changes in form and detail may be made therein without departing from the spirit and scope of the present disclosure as defined by the appended claims.

Claims

1. A method for preparing a mortar screed bar, characterized in that, The steps of the method are as follows: S1: Weigh the mortar for making rib strips that has been pre-stirred evenly, and mix it thoroughly through mechanical equipment in the early stage; S2: Add clean water into a container, and start low-speed stirring using a stirring device at the same time; during the continuous stirring process, slowly pour the weighed mortar into the water to make it fully blend with the clean water, and control the stirring time between 3 and 5 minutes to ensure the uniformity and appropriate fluidity of the mortar; S3: After stirring is completed, judge the state of the mortar to ensure that it reaches an appropriate fluidity (the fluidity value is about 180 mm), so as to ensure that it is easy to be injected into the resin mold and formed subsequently; S4: Pour the mixed mortar into the resin mold. The resin mold can form 20 to 25 rib strips at one time. During the grouting process, continuity and stability should be maintained to avoid entraining air bubbles or interruption; S5: When the mortar fills the resin mold, use an aluminum alloy trowel with a length of 0.8 m to scrape off the excess mortar along the parallel direction of the mold surface to make the surface smooth and flat and maintain a consistent height, so as to form a unified size; S6: Let the filled mold stand for 2 hours to make it harden naturally. During this period, vibration and external force interference should be avoided. When the mortar is completely hardened and the strength reaches more than 10 MPa, the demolding operation can be carried out. Careful operation should be taken during demolding to prevent damage to the rib strips or breakage of the corners; S7: The demolded rib strips are stacked at the designated position according to the predetermined specifications for natural curing. The curing period is about 10 days. During this period, keep the environment ventilated, avoid direct sunlight and rain erosion to ensure the stable performance and long service life of the rib strips.

2. The preparation method of a mortar screeding bar according to claim 1, characterized in that: The component ratio of the mortar is as follows: po52.5 cement: 200 parts - 300 parts, aluminate cement: 100 parts - 150 parts, powder polycarboxylate water reducer: 1 part - 2 parts, reinforcing agent: 5 parts - 8 parts, setting regulator: 10 parts, toughening agent: 10 parts, toughening agent: 5 parts, thickening agent: 0.5 part, fine sand with a diameter value of less than 1.0 mm: 550 parts - 700 parts, water: 400 - 450 parts.

3. A method for preparing a mortar screeding strip according to claim 2, characterized in that: The reinforcing agent includes sodium carbonate, the setting regulator includes calcium formate, the toughening agent includes PP fiber, the toughening agent includes wood fiber, and the thickening agent includes hydroxycellulose.

4. A method for preparing a mortar screed bar according to claim 1, characterized in that: Before injecting the mortar into the mold, spray a release agent with a thickness of 0.3 to 0.5 mm on the inner wall of the mold. The release agent is a water-based paraffin emulsion or a polyurethane emulsion to ensure that the mortar does not adhere to the mold surface and is conducive to the smooth demolding of the rib strips, and at the same time avoid corner breakage caused by difficult demolding.

5. The preparation method of a mortar screeding strip according to claim 1, characterized in that: After the grouting of the mold is completed, a vibrating table is used to assist in the compaction operation. The vibration frequency is controlled at 50 to 60 Hz, and the duration is 30 to 45 seconds to discharge the air bubbles in the mortar and improve its density, thereby significantly improving the compressive strength and surface flatness of the rib strips.

6. The preparation method of a mortar screeding strip according to claim 1, characterized in that: When using a trowel to scrape off the excess mortar, operate at a 45° angle and repeat the scraping twice longitudinally along the mold to ensure that the surface height of each rib strip is the same and eliminate the uneven error. The mortar scraped off each time during the scraping process can be recycled into the bucket for reuse to improve the material utilization rate.

7. A method for preparing a mortar screeding strip according to claim 1, characterized in that: During the natural curing period, the ribs are covered within the first 48 hours. The covering material is wet linen or plastic film. After covering, spray humidification is carried out no less than twice a day to keep the surface of the ribs always in a wet state, prevent early cracking, and improve the overall durability of the finished ribs.

8. A method for preparing a mortar screed bar according to claim 1, characterized in that: To control the color consistency of the rib surface, no more than 1% of inorganic gray pigment is added to the mortar. It is iron oxide powder or manganese oxide powder. After thorough mixing, the ribs can have consistent color and do not fade, meeting the engineering appearance requirements and not affecting the mortar performance.

9. A method for preparing a mortar screed bar according to claim 1, characterized in that: The forming mold is equipped with positioning pins and end limit devices to keep the length error of each rib within ±2 mm. At the same time, the mold adopts a reversible structure, which is convenient for overall reverse vibration compaction and demolding after grouting, improving production efficiency and operation safety.

10. A method for preparing a mortar screeding bar according to claim 1, characterized in that: During the mortar curing period, the environmental humidity shall not be lower than 60%, and the curing temperature is controlled within the range of 18°C to 30°C to avoid excessive water evaporation caused by high temperature or affecting the cement hydration reaction rate due to low temperature, thus ensuring that the rib strength gradually increases and meets the design requirements.

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