Super high-rise pump concrete and preparation method thereof

Abstract

The invention relates to the technical field of concrete, and discloses super high-rise pump concrete and a preparation method thereof.The super high-rise pump concrete is prepared from cement, aggregate, mineral admixtures, additives and water.The super high-rise pump concrete has excellent flowability and segregation resistance by means of the optimized component proportion and the scientific preparation technology, the slump is controlled to be 200-220 mm, and the slump of the super high-rise pump concrete is controlled to be 200-220 mm. The expansion degree is not smaller than 500 mm, the height and distance challenges of super high-rise pumping can be easily overcome in the pumping process, the pumping pressure is stabilized to be 10-15 MPa, the pumping speed is kept to be 30-50 m / h, the pumping resistance and the pipe blocking phenomenon are effectively reduced, the construction efficiency is greatly improved, the construction period is shortened, the construction cost is reduced, and the construction period is shortened. And the hardened concrete has high strength, can reliably bear huge vertical load and horizontal load of the super high-rise building, provides firm support for the building structure, and ensures the safety and stability of the building structure.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete, and particularly to a super high-rise pumped concrete and a preparation method thereof. Background Art

[0002] With the acceleration of the urbanization process, urban land resources have become increasingly scarce, prompting the construction industry to continuously develop towards higher altitudes. Super high-rise buildings have become an important symbol of modern urban construction. The construction of super high-rise buildings places extremely stringent requirements on the performance of concrete. Among them, the quality of super high-rise pumped concrete is directly related to the smooth progress of the project, structural safety and service life. However, traditional concrete exposes a series of problems that cannot be ignored when applied to super high-rise pumping: Poor pumping performance: Traditional concrete has poor fluidity. During the super high-rise pumping process, due to the large pumping height and long conveying distance, the friction between the concrete and the conveying pipeline increases significantly, resulting in a sharp rise in pumping resistance. This not only requires a large amount of pumping power, increasing construction costs, but also easily causes pipe blockage. Once the pipe is blocked, it is time-consuming and laborious to clean the pipeline, seriously affecting the construction progress, causing project delays, and increasing additional labor, material and time costs.

[0003] Prominent segregation and bleeding problems: During the super high-rise pumping process, affected by factors such as pumping pressure, the self-gravity of the concrete and long-term transportation, the aggregates and paste in traditional concrete are prone to separation, showing segregation. At the same time, water will precipitate from the concrete, resulting in the destruction of the uniformity of the concrete, with floating slurry or water patterns appearing on the surface, reducing the density and strength of the concrete, and thus affecting the overall performance and durability of the building structure.

[0004] Insufficient strength and durability: Super high-rise buildings serve for decades or even hundreds of years, and require concrete to have sufficient strength and excellent durability to withstand long-term gravity loads, wind loads and the erosion of various environmental factors. However, traditional concrete has limitations in strength growth and is difficult to meet the dual requirements of super high-rise buildings for early strength and late strength. Moreover, its impermeability, frost resistance and corrosion resistance are poor. Under the action of harsh environments such as acid rain and freeze-thaw cycles, the concrete structure is prone to damage phenomena such as cracks and spalling, shortening the service life of the building, increasing maintenance costs and safety hazards.

[0005] Unstable quality: Traditional concrete lacks strict standardization and refined management in raw material selection, mix design and preparation process, resulting in large fluctuations in the quality of different batches of concrete. It is difficult to ensure that each batch of concrete at the construction site can reach the ideal performance indicators. This instability of quality brings great uncertainty to the construction quality of super high-rise buildings and increases the risk of engineering quality accidents. Summary of the Invention

[0006] (1) Technical problems to be solved Aiming at the deficiencies of the prior art, the present invention provides a super high-rise pumped concrete and its preparation method, which has excellent workability, improves construction efficiency, etc., and solves the problem of poor pumping performance: traditional concrete has poor fluidity. During the super high-rise pumping process, due to the large pumping height and long conveying distance, the friction between the concrete and the conveying pipeline increases significantly, resulting in a sharp rise in pumping resistance.

[0007] (2) Technical solutions To achieve the above excellent workability and improve construction efficiency, the present invention provides the following technical solutions: a super high-rise pumped concrete and its preparation method, including cement, aggregate, mineral admixture, admixture and water. The cement: Portland cement with a strength grade of 52.5 is selected, and the dosage is controlled at 450 - 500 kg / m³; Among them, the aggregate: the coarse aggregate is crushed stone with continuous grading, the particle size is strictly controlled at 5 - 25 mm, the bulk density is not less than 1500 kg / m³, the mud content is less than 1%, and the dosage is 900 - 1000 kg / m³. The fine aggregate is medium sand, the fineness modulus is kept between 2.6 - 3.0, the mud content is less than 3%, and the dosage is 700 - 800 kg / m³. The medium sand has good particle shape and grading; Among them, the mineral admixture: Class I fly ash is selected for fly ash, the water demand ratio is not more than 95%, the loss on ignition is less than 5%, and the dosage is 50 - 80 kg / m³. Class I fly ash particles are fine and can fill the voids between cement particles, improving the microstructure of the concrete. Ground granulated blast-furnace slag powder with S95 grade is used for ground granulated blast-furnace slag powder, the specific surface area is not less than 400 m² / kg, and the activity index is not less than 95%, and the dosage is 30 - 50 kg / m³; Among them, the admixture: polycarboxylate high-performance water reducer is selected for the water reducer, the water reduction rate is not less than 25%, and the dosage is 1.0% - 1.5% of the total amount of cementitious materials. Polycarboxylate high-performance water reducer can, without increasing the water consumption, the dosage is 0.005% - 0.01% of the total amount of cementitious materials; Among them, the water: potable water meeting national standards is used, and the water-binder ratio is strictly controlled between 0.35 - 0.40.

[0008] Preferably, a preparation method of super high-rise pumped concrete is characterized in that it includes the following specific steps: S1 Inspection and preparation of raw materials: conduct comprehensive and strict inspections on cement, aggregate, mineral admixture, admixture and water to ensure that their various performance indicators fully meet the above design requirements; Among them, high-precision metering equipment is adopted to accurately measure various raw materials according to the design ratio, and the metering error is strictly controlled: the metering error of cement and mineral admixture is controlled within ±1%, the metering error of aggregate is controlled within ±2%, the metering error of admixture is controlled within ±0.5%, and the metering error of water is controlled within ±1%. Accurate metering is the basis for ensuring the quality stability of concrete; S2 Aggregate pre-wetting treatment: Put the coarse aggregate and fine aggregate together into the mixing equipment, add 10% - 15% of the total water consumption for pre-wetting and mixing, and set the mixing time to 60 - 90 seconds; S3 Mixing: First, put cement, fly ash, and slag powder into the mixer and mix for 30 - 40 seconds to make them preliminarily mixed evenly to form a uniform cementitious material system. Then, add the pre-wetted aggregate and continue to mix for 60 - 90 seconds to allow the aggregate to fully contact and wrap with the cementitious material, ensuring that the aggregate is evenly dispersed in the cementitious material. Then, fully mix the remaining water with water reducer and air-entraining agent to prepare a solution, and slowly add it to the mixer and mix for 120 - 150 seconds; S4 Quality inspection: After mixing is completed, immediately inspect the key properties of the concrete mixture, such as slump, spread, and air content. The slump should be controlled between 200 - 220mm, the spread should be not less than 500mm, and the air content should be controlled between 4% - 6%. If the inspection results do not meet the requirements, quickly analyze the reasons and timely adjust the raw material ratio or mixing process; S5 Transportation and pumping: Use a concrete mixer truck to transport the concrete. During transportation, the tank body rotates slowly, and the rotation speed is controlled at 2 - 4r / min to prevent the concrete from segregation. The transportation time is strictly controlled within sixty minutes to ensure that the concrete reaches the construction site before initial setting.

[0009] Preferably, for the S2 aggregate pre-wetting treatment, the pre-wetting treatment can make the surface of the aggregate fully wet, reduce the adsorption of free water in the concrete mixture by the aggregate during the subsequent mixing process, thereby effectively improving the workability of the concrete and avoiding segregation and bleeding phenomena caused by uneven water distribution.

[0010] Preferably, for the S3 mixing, during the whole mixing process, closely observe the state of the concrete mixture to ensure that it is evenly mixed, has the same color, no segregation and bleeding phenomena, and ensure the homogeneity of the concrete.

[0011] Preferably, for the S4 quality inspection, such as appropriately increasing the dosage of water reducer to improve fluidity, or adjusting the dosage of air-entraining agent to control the air content until all performance indicators meet the design requirements. Strict quality inspection is an important link to ensure the quality of concrete.

[0012] Preferably, for S5 transportation and pumping, when pumping, select the pumping equipment and pumping parameters reasonably according to the pumping height and distance. Control the pumping pressure at 10 - 15 MPa and the pumping speed at 30 - 50 m³ / h to ensure continuous and stable transportation of concrete to the pouring site and avoid problems such as pumping interruption or pipe blockage.

[0013] (III) Beneficial effects Compared with the prior art, the present invention provides a super high-rise pumped concrete and its preparation method, which have the following beneficial effects: 1. For the super high-rise pumped concrete and its preparation method, this solution has excellent working performance and improves construction efficiency: This super high-rise pumped concrete, with optimized ingredient ratios and scientific preparation processes, has excellent fluidity and segregation resistance. Its slump is controlled at 200 - 220 mm, and the spread is not less than 500 mm. During the pumping process, it can easily overcome the height and distance challenges of super high-rise pumping. The pumping pressure is stable at 10 - 15 MPa, and the pumping speed remains at 30 - 50 m³ / h, effectively reducing the occurrence of pumping resistance and pipe blockage. This not only greatly improves construction efficiency, shortens the construction period, but also reduces construction costs and economic losses caused by construction delays.

[0014] 2. For the super high-rise pumped concrete and its preparation method, this solution has high strength and high durability, ensuring building safety: The hardened concrete has high strength and can reliably bear the huge vertical and horizontal loads of super high-rise buildings, providing a solid support for the building structure and ensuring the safety and stability of the building structure. At the same time, by reasonably selecting mineral admixtures and admixtures, the durability of the concrete is effectively improved, and its impermeability, frost resistance, and erosion resistance are significantly enhanced. It can effectively resist the erosion of harsh environments such as acid rain and freeze-thaw cycles, extend the service life of super high-rise buildings, reduce long-term maintenance costs, and ensure the long-term safe use of buildings.

[0015] 3. For the super high-rise pumped concrete and its preparation method, this solution has high-quality stability and reduces safety risks: From raw material inspection, metering control to the preparation process, the whole process strictly follows standardized procedures. High-precision metering equipment ensures that the metering errors of raw materials are extremely small. The metering errors of cement and mineral admixtures are controlled within ±1%, those of aggregates are within ±2%, those of admixtures are within ±0.5%, and those of water are within ±1%. Standardized mixing, testing, transportation, and pumping links make the quality of each batch of concrete highly stable and consistent. This provides a reliable quality guarantee for super high-rise building construction, greatly reducing engineering quality problems caused by concrete quality fluctuations, effectively reducing safety risks, and ensuring the life safety of construction workers and the long-term safety of building users. Detailed implementation manners

[0016] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0017] This solution provides a technical solution, specifically, a super high-rise pumped concrete, including cement, aggregate, mineral admixture, admixture and water; Among them, for cement: Portland cement with a strength grade of 52.5 is selected, and the dosage is controlled within 450 - 500 kg / m³. This type of cement has a rapid early strength development, enabling the concrete to have a certain strength within a short time after pumping, facilitating subsequent construction operations; at the same time, its heat of hydration is moderate, which can effectively avoid the excessive internal temperature of the concrete caused by too much heat of hydration, thereby preventing cracks from occurring, ensuring the stability of the concrete during the pumping process and the strength requirements after hardening, and laying a foundation for the structural safety of super high-rise buildings; For aggregate: The coarse aggregate uses continuously graded gravel, with the particle size strictly controlled within 5 - 25 mm, the bulk density not less than 1500 kg / m³, and the mud content less than 1%. The dosage is 900 - 1000 kg / m³. The continuously graded gravel can be closely packed, minimizing the voids between the aggregates to significantly enhance the density of the concrete, improving the compressive strength and impermeability of the concrete. The fine aggregate is medium sand, with the fineness modulus maintained between 2.6 - 3.0, the mud content less than 3%, and the dosage is 700 - 800 kg / m³. The good particle shape and grading of the medium sand provide excellent workability and pumpability for the concrete, enabling it to flow smoothly during the pumping process and reducing the risk of pipeline blockage; For mineral admixture: Class I fly ash is selected, with the water demand ratio not greater than 95% and the loss on ignition less than 5%. The dosage is 50 - 80 kg / m³. The Class I fly ash particles are fine, which can fill the voids between the cement particles, improving the microscopic structure of the concrete, thus effectively improving the workability of the concrete, reducing the heat of hydration, and enhancing the crack resistance and durability of the concrete. The slag powder uses S95 grade slag powder, with a specific surface area not less than 400 m² / kg and an activity index not less than 95%. The dosage is 30 - 50 kg / m³. The slag powder participates in the secondary hydration reaction in the concrete, which can improve the later strength of the concrete, enhance the impermeability and corrosion resistance of the concrete, and extend the service life of super high-rise buildings; Admixtures: For the water reducer, a polycarboxylate high-performance water reducer is selected, with a water reduction rate of not less than 25% and a dosage of 1.0% - 1.5% of the total amount of cementitious materials. The polycarboxylate high-performance water reducer can significantly improve the fluidity of concrete without increasing the water consumption, and at the same time enhance the strength of concrete. For the air-entraining agent, a rosin thermopolymer air-entraining agent is used, with a dosage of 0.005% - 0.01% of the total amount of cementitious materials. This air-entraining agent can introduce a large number of uniformly stable micro-bubbles into the concrete. These bubbles are like ball bearings, reducing the frictional resistance between aggregates and further improving the fluidity of concrete. At the same time, the micro-bubbles can also block the capillary channels inside the concrete, enhance the frost resistance and impermeability of concrete, and improve the performance of concrete in harsh environments; Water: Potable water meeting national standards is used, and the water-binder ratio is strictly controlled between 0.35 - 0.40. An appropriate water-binder ratio is a key factor in ensuring the performance of concrete. It can not only ensure that the concrete has good fluidity and meets the requirements of super high-rise pumping construction, but also ensure the full hydration of cement, enabling the concrete to obtain sufficient strength and durability; A method for preparing super high-rise pumping concrete includes the following specific steps. S1 Raw material inspection and preparation: Cement, aggregates, mineral admixtures, admixtures, and water are comprehensively and strictly inspected to ensure that their various performance indicators fully meet the above design requirements; Among them, high-precision metering equipment is used to accurately measure various raw materials according to the design ratio, and the metering error is strictly controlled: the metering error of cement and mineral admixtures is controlled within ±1%, the metering error of aggregates is controlled within ±2%, the metering error of admixtures is controlled within ±0.5%, and the metering error of water is controlled within ±1%. Precise metering is the basis for ensuring the quality stability of concrete; S2 Aggregate pre-wetting treatment: The coarse and fine aggregates are put into the mixing equipment together, and 10% - 15% of the total water consumption is added for pre-wetting and mixing, and the mixing time is set to 60 - 90 seconds; Among them, the pre-wetting treatment can fully wet the surface of the aggregates, reduce the adsorption of free water in the concrete mixture by the aggregates during the subsequent mixing process, thereby effectively improving the workability of the concrete and avoiding segregation and bleeding phenomena caused by uneven water distribution; S3 Mixing: First, cement, fly ash, and slag powder are put into the mixer and mixed for 30 - 40 seconds to form a uniform cementitious material system. Then, the pre-wetted aggregates are added and mixed for another 60 - 90 seconds to ensure that the aggregates are fully in contact with and wrapped by the cementitious materials, and the aggregates are evenly dispersed in the cementitious materials. Then, the remaining water is fully mixed with the water reducer and air-entraining agent to form a solution, which is slowly added to the mixer and mixed for 120 - 150 seconds; Among them, during the entire mixing process, closely observe the state of the concrete mixture to ensure that it is evenly mixed, has a consistent color, no segregation or bleeding phenomenon, and guarantee the homogeneity of the concrete; S4 Quality inspection: After mixing is completed, immediately inspect the key properties of the concrete mixture, such as slump, spread, and air content. The slump should be controlled between 200 - 220mm, the spread should be not less than 500mm, and the air content should be controlled between 4% - 6%. If the test results do not meet the requirements, quickly analyze the reasons and promptly adjust the raw material ratio or mixing process; Among them, for example, appropriately increase the dosage of water reducer to improve fluidity, or adjust the dosage of air-entraining agent to control the air content until all performance indicators meet the design requirements. Strict quality inspection is an important link to ensure the quality of concrete; S5 Transportation and pumping: Use a concrete mixer truck to transport the concrete. During transportation, the tank body rotates slowly, and the rotation speed is controlled at 2 - 4r / min to prevent concrete segregation. The transportation time is strictly controlled within sixty minutes to ensure that the concrete reaches the construction site before initial setting; Among them, for S5 transportation and pumping, during pumping, reasonably select the pumping equipment and pumping parameters according to the pumping height and distance. The pumping pressure is controlled at 10 - 15MPa, and the pumping speed is controlled at 30 - 50m³ / h to ensure that the concrete is continuously and stably transported to the pouring site, and avoid problems such as pumping interruption or pipe blockage; Furthermore, the excellent working performance of this solution improves construction efficiency: This ultra-high-rise pumped concrete, with its optimized composition ratio and scientific preparation process, has excellent fluidity and segregation resistance. Its slump is controlled between 200 - 220mm, and the spread is not less than 500mm. During pumping, it can easily overcome the challenges of height and distance in ultra-high-rise pumping. The pumping pressure is stable at 10 - 15MPa, and the pumping speed remains at 30 - 50m³ / h, effectively reducing the occurrence of pumping resistance and pipe blockage. This not only greatly improves construction efficiency, shortens the construction period, but also reduces construction costs and economic losses caused by construction delays; Furthermore, the high strength and high durability of this solution guarantee building safety: The hardened concrete has high strength and can reliably bear the huge vertical and horizontal loads of ultra-high-rise buildings, providing a solid support for the building structure and ensuring the safety and stability of the building structure. At the same time, by reasonably selecting mineral admixtures and admixtures, the durability of the concrete is effectively improved, and its impermeability, frost resistance, and erosion resistance are significantly enhanced. It can effectively resist the erosion of harsh environments such as acid rain and freeze-thaw cycles, extend the service life of ultra-high-rise buildings, reduce long-term maintenance costs, and guarantee the long-term safe use of buildings; Furthermore, this solution has high stability in quality and reduces safety risks: from raw material inspection, metering control to the preparation process, the whole process strictly follows standardized procedures. High-precision metering equipment ensures that the metering errors of raw materials are extremely small. The metering errors of cement and mineral admixtures are controlled within ±1%, those of aggregates within ±2%, those of admixtures within ±0.5%, and those of water within ±1%. Standardized mixing, testing, and transportation and pumping processes make the quality of each batch of concrete highly stable and consistent. This provides reliable quality assurance for the construction of super high-rise buildings, greatly reduces engineering quality problems caused by concrete quality fluctuations, effectively reduces safety risks, and ensures the life safety of construction workers and the long-term safety of building users.

[0018] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A super high-rise pumped concrete and its preparation method, comprising cement, aggregate, mineral admixture, admixture and water, characterized in that: The cement: Portland cement with a strength grade of 52.5 is selected, and the dosage is controlled at 450 - 500 kg / m³; Among them, the aggregate: The coarse aggregate is crushed stone with a continuous gradation, the particle size is strictly controlled at 5 - 25 mm, the bulk density is not less than 1500 kg / m³, the mud content is less than 1%, and the dosage is 900 - 1000 kg / m³. The fine aggregate is medium sand, the fineness modulus is maintained between 2.6 - 3.0, the mud content is less than 3%, and the dosage is 700 - 800 kg / m³. The medium sand has good particle shape and gradation; Among them, the mineral admixture: Class I fly ash is selected for fly ash, the water demand ratio is not greater than 95%, the loss on ignition is less than 5%, and the dosage is 50 - 80 kg / m³. The Class I fly ash has fine particles, can fill the voids between cement particles, and improve the microscopic structure of concrete. The slag powder is S95 grade slag powder, the specific surface area is not less than 400 m² / kg, and the activity index is not less than 95%, and the dosage is 30 - 50 kg / m³; Among them, the admixture: A polycarboxylate high-performance water reducer is selected for the water reducer, the water reduction rate is not less than 25%, and the dosage is 1.0% - 1.5% of the total amount of cementitious materials. The polycarboxylate high-performance water reducer can, without increasing the water consumption, the dosage is 0.005% - 0.01% of the total amount of cementitious materials; Among them, the water: Drinking water that meets national standards is used, and the water-binder ratio is strictly controlled between 0.35 - 0.

40.

2. A method for preparing ultra-high-rise pumped concrete, characterized in that: It includes the following specific steps. S1 Raw material inspection and preparation: Conduct a comprehensive and strict inspection of cement, aggregate, mineral admixture, admixture and water to ensure that their various performance indicators fully meet the above design requirements; Among them, high-precision metering equipment is used to accurately measure various raw materials according to the design ratio, and the metering error is strictly controlled: The metering error of cement and mineral admixture is controlled within ±1%, the metering error of aggregate is controlled within ±2%, the metering error of admixture is controlled within ±0.5%, and the metering error of water is controlled within ±1%. Accurate metering is the basis for ensuring the quality stability of concrete; S2 Aggregate pre-wetting treatment: Put the coarse aggregate and fine aggregate into the mixing equipment together, add 10% - 15% of the total water consumption for pre-wetting and mixing, and the mixing time is set to 60 - 90 seconds; S3 Mixing: First, put the cement, fly ash, and slag powder into the mixer and mix for 30 - 40 seconds to make them preliminarily mixed evenly to form a uniform cementitious material system. Then, add the pre-wetted aggregate and continue to mix for 60 - 90 seconds to allow the aggregate to fully contact and wrap with the cementitious material, ensuring that the aggregate is evenly dispersed in the cementitious material. Then, fully mix the remaining water with the water reducer and air-entraining agent to form a solution, and slowly add it to the mixer and mix for 120 - 150 seconds; S4 Quality Inspection: After the mixing is completed, immediately inspect the key properties of the fresh concrete mixture, including slump, spread, and air content. The slump should be controlled between 200 - 220 mm, the spread should be no less than 500 mm, and the air content should be controlled between 4% - 6%. If the test results do not meet the requirements, quickly analyze the reasons and promptly adjust the raw material ratio or mixing process; S5 Transportation and Pumping: Use a concrete mixer truck to transport the concrete. During transportation, the tank body rotates slowly at a speed of 2 - 4 r / min to prevent concrete segregation. The transportation time is strictly controlled within sixty minutes to ensure that the concrete reaches the construction site before initial setting.

3. A method for preparing ultra-high-rise pumped concrete according to claim 2, characterized in that: For the S2 aggregate pre-wetting treatment described above, the pre-wetting treatment can fully wet the surface of the aggregates, reducing the adsorption of free water in the fresh concrete mixture by the aggregates during subsequent mixing, thereby effectively improving the workability of the concrete and avoiding segregation and bleeding phenomena caused by uneven water distribution.

4. A method for preparing ultra-high-rise pumped concrete according to claim 2, characterized in that: For the S3 mixing described above, during the entire mixing process, closely observe the state of the fresh concrete mixture to ensure that it is evenly mixed, has a consistent color, and shows no segregation or bleeding phenomena, guaranteeing the homogeneity of the concrete.

5. A method for preparing ultra-high-rise pumped concrete according to claim 2, characterized in that: For the S4 quality inspection described above, appropriately increase the dosage of water reducer to improve fluidity, or adjust the dosage of air-entraining agent to control the air content until all performance indicators meet the design requirements. Strict quality inspection is an important link to ensure the quality of concrete.

6. A method for preparing ultra-high-rise pumped concrete according to claim 2, characterized in that: For the S5 transportation and pumping described above, during pumping, reasonably select the pumping equipment and pumping parameters according to the pumping height and distance. The pumping pressure is controlled between 10 - 15 MPa, and the pumping speed is controlled between 30 - 50 m³ / h to ensure continuous and stable transportation of the concrete to the pouring site and avoid pumping interruption or pipe blockage problems.