Machine-made sand high-performance concrete based on ultra-long span catwalk pumping requirement

Abstract

The invention provides machine-made sand high-performance concrete based on ultra-long span catwalk pumping requirements, and relates to the technical field of concrete, the machine-made sand high-performance concrete is prepared from the following raw materials by mass: 10%-12% of cement, 3%-5% of fly ash, 0.5%-1% of silica fume, 6%-8% of water, 35%-40% of sand, 30%-50% of 5-20mm gravel and 0.1%-0.3% of an additive; the admixture is prepared from the following raw materials in percentage by mass: 10%-30% of water-reducing mother liquor, 10%-30% of slump-retaining mother liquor, 5%-15% of sodium gluconate, 1%-3% of sodium tripolyphosphate, 0-2% of a water-retaining agent, 0%-0.2% of an air entraining agent and 30%-50% of water. The machine-made sand high-performance concrete based on the ultra-long span catwalk pumping requirement has the advantages of being good in workability and excellent in compressive strength, and the high-performance concrete meeting pumping with the span exceeding 500 m and light compressive strength at the same time is provided.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete, in particular to a manufactured sand high-performance concrete based on the pumping requirements of an ultra-long span catwalk. Background Art

[0002] At present, catwalk structures have been widely used in the construction of suspension bridges and other bridges. At the same time, as a key material for bridge construction, the improvement of the performance of manufactured sand concrete and the research on construction technology are particularly crucial in alpine and canyon areas. In recent years, the academic community has conducted in-depth research on the lithological characteristics and quality control of manufactured sand, the design methods of high-performance concrete and its performance optimization, etc., to meet the engineering requirements of different geographical characteristics, application structures, service environments, and strength requirements. However, under extreme conditions such as high altitude and low temperature, pumped manufactured sand concrete is prone to problems such as poor fluidity, unstable pumping performance, and strength decline, which seriously interfere with the construction quality and progress; especially when facing a catwalk with a span exceeding 500 meters as the pumping pipeline support system, the existing technology has not been able to provide concrete that meets the requirements of such projects. Summary of the Invention

[0003] The present invention provides a manufactured sand high-performance concrete based on the pumping requirements of an ultra-long span catwalk, aiming to solve at least one of the technical problems existing in the prior art mentioned in the background art.

[0004] The present invention provides the following technical solutions to achieve the above object:

[0005] A manufactured sand high-performance concrete based on the pumping requirements of an ultra-long span catwalk is made from raw materials including the following mass percentages: 10% - 12% of cement, 3% - 5% of fly ash, 0.5% - 1% of silica fume, 6% - 8% of water, 35% - 40% of sand, 30% - 50% of 5 - 20 mm crushed stone, and 0.1% - 0.3% of an admixture; the admixture is made from raw materials including the following mass percentages: 10% - 30% of a water-reducing mother liquor, 10% - 30% of a slump-retention mother liquor, 5% - 15% of sodium gluconate, 1% - 3% of sodium tripolyphosphate, 0 - 2% of a water retention agent, 0 - 0.2% of an air-entraining agent, and 30% - 50% of water.

[0006] Furthermore, the crushed stone is divided into two groups according to the particle sizes of 5 - 10 mm and 10 - 20 mm, and the mass ratio of the 5 - 10 mm crushed stone to the 10 - 20 mm crushed stone is 3.5:6.5.

[0007] Furthermore, it includes 11.08% cement, 3.96% fly ash, 0.79% silica fume, 6.81% water, 0.19% admixture, 37.04% sand, 12.04% crushed stone with a particle size of 5 - 10 mm, and 28.09% crushed stone with a particle size of 5 - 20 mm; the admixture is made from raw materials including the following mass percentages: 22% water - reducing mother liquor, 22% slump - retaining mother liquor, 10% sodium gluconate, 1.8% sodium tripolyphosphate, 0.9% water - retaining agent, 0.1% air - entraining agent, and 43.2% water.

[0008] Furthermore, the water - binder ratio of the manufactured - sand high - performance concrete is 0.41 - 0.43, the sand ratio is 45 - 50%, and the total amount of cementitious materials is 360 - 380 kg / m 3 .

[0009] Furthermore, the sand ratio of the manufactured - sand high - performance concrete is 48%, and the total amount of cementitious materials is 370 kg / m 3 .

[0010] A preparation method of manufactured - sand high - performance concrete based on the pumping requirements of a catwalk with an ultra - long span includes the following steps:

[0011] Put cement, fly ash, and silica fume into a mixer according to the ratio and conduct dry mixing until the admixtures are evenly dispersed;

[0012] Subsequently, add manufactured sand and crushed stone with a particle size of 5 - 10 mm and 10 - 20 mm with a mass ratio of 3.5:6.5 according to the ratio, and continue dry mixing until a uniform aggregate - cementitious material mixture is formed;

[0013] Divide the water into two portions with a mass ratio of 80%:20% and add them in batches. First, add the mixed solution of 80% of the mass of water and the admixture and conduct stirring, and finally add the remaining 20% of the mass of water and stir to obtain the manufactured - sand high - performance concrete.

[0014] Beneficial effects

[0015] Compared with the prior art, the present invention has the following beneficial effects: good workability and excellent compressive strength, meeting the pumping conditions for a catwalk with a span exceeding 500 meters as a pumping pipeline support system. Description of the drawings

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings described below only relate to some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

[0017] Figure 1 It is a comparison chart of the workability of concrete with different water-binder ratios of the present invention;

[0018] Figure 2 It is a comparison chart of the compressive strength of concrete with different water-binder ratios of the present invention;

[0019] Figure 3 It is a comparison chart of the workability of concrete with different sand ratios of the present invention;

[0020] Figure 4 It is a comparison chart of the compressive strength of concrete with different sand ratios of the present invention;

[0021] Figure 5 It is a comparison chart of the workability of concrete with different cementitious materials of the present invention;

[0022] Figure 6 It is a comparison chart of the compressive strength of concrete with different cementitious materials of the present invention;

[0023] Figure 7 It is a comparison chart of the workability of concrete with different particle size combinations of crushed stones of the present invention;

[0024] Figure 8 It is a comparison chart of the compressive strength of concrete with different particle size combinations of crushed stones of the present invention;

[0025] Figure 9 It is a comparison chart of the workability of concrete with different mineral admixtures of the present invention;

[0026] Figure 10 It is a comparison chart of the compressive strength of concrete with different mineral admixtures of the present invention;

[0027] Figure 11 It is a comparison chart of the workability of concrete with different admixtures of the present invention;

[0028] Figure 12 It is a comparison chart of the compressive strength of concrete with different admixtures of the present invention. Detailed implementation manners

[0029] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0030] It should be noted that in the present invention: The terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that comprises a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices; The terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe the present invention and its embodiments, and are not used to limit that the indicated devices, elements or components must have a specific orientation or be constructed and operated in a specific orientation; The terms "first", "second", etc. are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence; The terms "installed", "set", "provided with", "connected", "coupled", "socketed", etc. should be understood in a broad sense; For example, it can be a fixed connection, a detachable connection, or an integral structure; It can be a mechanical connection or an electrical connection; It can be directly connected, or indirectly connected through an intermediate medium, or there can be internal communication between two devices, elements or components. And, in addition to being able to represent an orientation or positional relationship, some terms may also be used to represent other meanings. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in the present invention can be understood according to specific circumstances.

[0031] Example 1. A high-performance manufactured-sand concrete based on the pumping requirements of an ultra-long-span catwalk is made from raw materials including the following mass percentages: 11.08% cement, 3.96% fly ash, 0.79% silica fume, 6.81% water, 0.19% admixture, 37.04% sand, 12.04% gravel with a particle size of 5 - 10 mm, and 28.09% gravel with a particle size of 5 - 20 mm; The admixture is made from raw materials including the following mass percentages: 22% water-reducing mother liquor, 22% slump-retention mother liquor, 10% sodium gluconate, 1.8% sodium tripolyphosphate, 0.9% water-retaining agent, 0.1% air-entraining agent, and 43.2% water. The gravel is divided into two groups according to the particle sizes of 5 - 10 mm and 10 - 20 mm, and the mass ratio of the gravel with a particle size of 5 - 10 mm to the gravel with a particle size of 10 - 20 mm is 3.5:6.5.

[0032] The cement used is P·O 42.5 cement produced by Shuicheng Conch Panjiang Cement Co., Ltd.;

[0033] The fly ash used is Class F Grade II fly ash produced by Funeng (Guizhou) Power Generation Co., Ltd.;

[0034] The silica fume used is the 92D silica fume produced by Zunyi Lianfeng Industry and Trade Co., Ltd.;

[0035] The manufactured sand is the medium sand in Zone II produced by the self-built aggregate yard of the fourth section of Anpan Expressway, with a fineness modulus of 2.7, a stone powder content of 12.0%, and an MB value of 1.0;

[0036] The crushed stones are two specifications of crushed stones of 5-10 mm and 10-20 mm produced by the self-built aggregate yard of the fourth section of Anpan Expressway.

[0037] A preparation method of manufactured sand high-performance concrete based on the pumping requirements of an ultra-long span catwalk, characterized by comprising the following steps:

[0038] Put cement, fly ash and silica fume into a mixer in proportion and conduct dry mixing until the admixtures are evenly dispersed; the micro-aggregate effect of mineral admixtures can be fully activated by pre-mixing the cementitious materials;

[0039] Subsequently, add manufactured sand and crushed stones with particle sizes of 5-10 mm and 10-20 mm with a mass ratio of 3.5:6.5 in proportion, and continue dry mixing until a uniform aggregate-cementitious material mixture is formed; a dense packing structure is formed by adding graded aggregates to the cementitious materials and stirring.

[0040] Add water in two batches with a mass ratio of 80%:20%. First, add the mixed solution of 80% mass portion of water and admixtures and stir. Finally, add the remaining 20% mass portion of water and stir to obtain the manufactured sand high-performance concrete. By adding liquid materials in stages, it is ensured that the admixture molecules are directionally adsorbed on the surface of cement particles, thereby ensuring the full play of the concrete performance.

[0041] Example 2. A manufactured sand high-performance concrete based on the pumping requirements of an ultra-long span catwalk is made of raw materials including the following mass percentages: 11.08% of cement, 3.96% of fly ash, 0.79% of silica fume, 6.81% of water, 0.19% of admixtures, 37.04% of sand, 12.04% of crushed stones with a particle size of 5-10 mm, and 28.09% of crushed stones with a particle size of 5-20 mm; the admixtures are made of raw materials including the following mass percentages: 22% of water-reducing mother liquor, 22% of slump-retention mother liquor, 7% of sodium gluconate, 1.8% of sodium tripolyphosphate, 0.9% of water retention agent, 0.2% of air-entraining agent, and 46.1% of water.

[0042] Example 3. A manufactured sand high-performance concrete based on the pumping requirements of an ultra-long-span catwalk is made from raw materials including the following mass percentages: 11.08% cement, 3.96% fly ash, 0.79% silica fume, 6.81% water, 0.19% admixture, 37.04% sand, 12.04% gravel with a particle size of 5-10 mm, and 28.09% gravel with a particle size of 5-20 mm; the admixture is made from raw materials including the following mass percentages: 22% water-reducing mother liquor, 22% slump-retention mother liquor, 7% sodium gluconate, 1.8% sodium tripolyphosphate, 0.9% water retainer, 0.1% air-entraining agent, and 46.2% water.

[0043] Example 4. A manufactured sand high-performance concrete based on the pumping requirements of an ultra-long-span catwalk is made from raw materials including the following mass percentages: 11.08% cement, 3.96% fly ash, 0.79% silica fume, 6.81% water, 0.19% admixture, 37.04% sand, 12.04% gravel with a particle size of 5-10 mm, and 28.09% gravel with a particle size of 5-20 mm; the admixture is made from raw materials including the following mass percentages: 25% water-reducing mother liquor, 25% slump-retention mother liquor, 10% sodium gluconate, 2% sodium tripolyphosphate, 1% water retainer, 0.1% air-entraining agent, and 36.9% water.

[0044] Example 5. A manufactured sand high-performance concrete based on the pumping requirements of an ultra-long-span catwalk is made from raw materials including the following mass percentages: 11.08% cement, 3.96% fly ash, 0.79% silica fume, 6.81% water, 0.19% admixture, 37.04% manufactured sand, 12.04% gravel with a particle size of 5-10 mm, and 28.09% gravel with a particle size of 5-20 mm; the admixture is made from raw materials including the following mass percentages: 22% water-reducing mother liquor, 22% slump-retention mother liquor, 10% sodium gluconate, 1.8% sodium tripolyphosphate, 0.9% water retainer, 0.1% air-entraining agent, and 43.2% water, where the total weight of the cementitious materials, namely cement, fly ash, and silica fume, is 360 kg / m 3 .

[0045] Example 6. A high-performance manufactured-sand concrete based on the pumping requirements of an ultra-long-span catwalk is made from raw materials including the following by mass percentage: 11.08% cement, 3.96% fly ash, 0.79% silica fume, 6.81% water, 0.19% admixture, 37.04% manufactured sand, 12.04% crushed stone with a particle size of 5 - 10 mm, and 28.09% crushed stone with a particle size of 5 - 20 mm; the admixture is made from raw materials including the following by mass percentage: 22% water-reducing mother liquor, 22% slump-retention mother liquor, 10% sodium gluconate, 1.8% sodium tripolyphosphate, 0.9% water-retaining agent, 0.1% air-entraining agent, and 43.2% water, where the total weight of the binder materials, namely cement, fly ash, and silica fume, is 370 kg / m 3 .

[0046] Example 7. A high-performance manufactured-sand concrete based on the pumping requirements of an ultra-long-span catwalk is made from raw materials including the following by mass percentage: 11.08% cement, 3.96% fly ash, 0.79% silica fume, 6.81% water, 0.19% admixture, 37.04% manufactured sand, 12.04% crushed stone with a particle size of 5 - 10 mm, and 28.09% crushed stone with a particle size of 5 - 20 mm; the admixture is made from raw materials including the following by mass percentage: 22% water-reducing mother liquor, 22% slump-retention mother liquor, 10% sodium gluconate, 1.8% sodium tripolyphosphate, 0.9% water-retaining agent, 0.1% air-entraining agent, and 43.2% water, where the total weight of the binder materials, namely cement, fly ash, and silica fume, is 380 kg / m 3 .

[0047] Test example. The workability test of the concrete refers to the "Standard Test Method for Performance of Ordinary Concrete Mixtures" (GB / T 50080 - 2016). The flowability of the concrete is evaluated by slump and slump flow, the cohesiveness of the concrete is evaluated by the emptying time of an inverted slump cone, the air content of the mixture is measured by an air content tester, and the segregation resistance performance of the mixture is evaluated by the segregation resistance performance test. The mechanical property test of the concrete refers to the "Standard Test Method for Physical and Mechanical Properties of Concrete" (GB / T 50081 - 2019). Cubic specimens with a side length of 150 mm are molded to test their compressive strengths at 3 d, 7 d, and 28 d.

[0048] The influence of different water-binder ratios on the performance of C30 concrete is shown in Figure 1 and Figure 2。When the water-binder ratio is controlled between 0.41 and 0.43, the fluidity and cohesiveness of the concrete are good, there is a slight piling phenomenon, and there is no segregation and bleeding. Under the condition of ensuring that the changes in slump and spread are not obvious, as the water-binder ratio increases, the dosage of the admixture decreases accordingly. The slump of the concrete mixture gradually increases from 210 mm to 225 mm, and the spread is the largest at 620 mm when the water-binder ratio is 0.43, and the slump time gradually decreases. At the same time, as the water-binder ratio increases, the compressive strength of the concrete decreases accordingly. When the water-binder ratio is lower than 0.43, the 28-day compressive strength of the concrete meets the design strength value requirements of C30 concrete. Compared with the concrete with a water-binder ratio of 0.43, the 28-day compressive strengths of the concrete with water-binder ratios of 0.41 and 0.43 increase by 13.3% and decrease by 7.2% respectively. Although a low water-binder ratio can improve the strength of the concrete, it will affect the workability and pumping performance of the concrete, while an excessive water-binder ratio will reduce the strength of the concrete. Therefore, when preparing C30 concrete, the water-binder ratio should be controlled below 0.43.

[0049] The influence of different sand ratios on the performance of C30 concrete is shown in Figure 3 and Figure 4 。When the sand ratio is between 45% and 50%, the fluidity and cohesiveness of the concrete are good, and there is no piling, segregation, and bleeding. As the sand ratio increases, the dosage of the admixture increases accordingly, the wrapping property of the mixture gradually improves, the slump remains unchanged, the spread first increases and then decreases and is the highest at 560 mm when the sand ratio is 48%, and the slump time also first increases and then decreases and is the highest at 11.5 s when the sand ratio is 48%. At the same time, regardless of the change in the sand ratio, the 28-day compressive strength of the concrete meets the design strength value requirements of C30 concrete. As the sand ratio increases, the 28-day compressive strength of the concrete first increases and then decreases and is the highest at 47.9 MPa when the sand ratio is 48%. Compared with the concrete with a sand ratio of 48%, the 28-day compressive strengths of the concrete with sand ratios of 45% and 50% decrease by 11.3% and 8.4% respectively. Increasing the sand ratio can effectively fill the voids between the aggregates, making the hardened cement matrix form a denser structure. However, an excessive sand ratio will lead to a decrease in the amount of cement paste, thereby reducing the bonding effect between the matrix and the aggregates and ultimately affecting the strength of the concrete. Therefore, the optimal sand ratio in this study should be 48%.

[0050] The influence of different total amounts of cementitious materials on the performance of C30 concrete is shown in Figure 6 and Figure 6As shown in the figure. When the total amount of cementitious materials is 360 kg / m3 to 380 kg / m3, the fluidity, cohesiveness and wrapping property of the concrete are good, without any phenomena of stockpiling and segregation bleeding. With the increase of the total amount of cementitious materials, both the slump and the spread first increase and then decrease, and the collapse time decreases accordingly. When the total amount of cementitious materials is 370 kg / m3, the workability of the fresh concrete is the best, with a slump of 225 mm, a spread of 610 mm, and a collapse time of 15 s. With the increase of the total amount of cementitious materials, the 28-day compressive strength of the concrete increases. When the total amount of cementitious materials is not less than 370 kg / m3, the 28-day compressive strength of the concrete meets the requirements of the designed strength value of C30 concrete. Compared with the concrete with a total amount of cementitious materials of 360 kg / m3, the 28-day compressive strengths of the concretes with total amounts of cementitious materials of 370 kg / m3 and 380 kg / m3 increase by 12.8% and 18.1% respectively. Therefore, an appropriate total amount of cementitious materials is beneficial to improving the workability of the mixture and can also ensure the mechanical properties of the concrete. Under the condition of meeting the work requirements, the total amount of cementitious materials can be appropriately reduced to seek higher economic benefits. Therefore, the total amount of cementitious materials in this study should be 370 kg / m 3 , therefore, to meet the pumping requirements, the optimal composition of the cementitious materials is Example 6.

[0051] The influence of the proportion of coarse aggregates with different particle sizes on the performance of C30 concrete is shown in Figure 7 and Figure 8 As shown. When the compound ratio of 5-10 mm:10-20 mm crushed stones is controlled at 2:8, 3:7, 3.5:6.5, 4:6, the fluidity and cohesiveness of the fresh concrete are good, without any phenomena of stockpiling and segregation bleeding. Among them, when the ratio is 4:6, the wrapping property between the paste and the aggregates becomes significantly worse. With the increase of the crushed stone ratio, the workability of the fresh concrete shows an obvious fluctuating trend, while the 28-day compressive strength of the concrete gradually increases. The maximum spread value appears at 3.5:6.5, which is 560 mm. It can be found that except for the test group with a crushed stone ratio of 2:8, the 28-day compressive strengths of the other groups meet the requirements of the designed strength value of C30 concrete. Compared with the test group with a crushed stone ratio of 2:8, the 28-day compressive strengths of the test groups with crushed stone ratios of 3:7, 3.5:6.5, 4:6 increase by 20.7%, 20.7%, 29.2% respectively. Therefore, the optimal proportion of coarse aggregates in this study should be 3.5:6.5.

[0052] The influence of different mineral admixtures on the performance of C30 concrete is shown in Figure 9 and Figure 10The influence of different mineral admixtures and their compound admixture ratios on the workability and mechanical properties of concrete is significant. The fluidity, cohesiveness, and wrapping property of the concrete mixtures in all groups are good, and there are no phenomena of material accumulation, segregation, and bleeding. When silica fume is not added, as the fly ash content increases, the slump of the concrete mixture fluctuates slightly, while the spread shows a trend of first decreasing, then increasing, and finally decreasing, and the slump flow time decreases linearly. The 28-day compressive strength of the concrete is the highest at 58.3 MPa when no fly ash is added (the reference group), and it gradually decreases as the fly ash content decreases. Compared with the reference group, the 28-day compressive strengths of the test groups with fly ash contents of 30%, 35%, and 40% are reduced by 19.2%, 26.9%, and 39.5% respectively. When 5% silica fume is added, as the fly ash content increases, the slump of the concrete mixture fluctuates slightly, while the spread shows a trend of first increasing, then decreasing, and finally decreasing, and the slump flow time decreases linearly. As the fly ash content increases, the 28-day compressive strength of the concrete first decreases and then increases, and it is the lowest at 30.7 MPa when the fly ash content is 35%. When the fly ash content remains unchanged at 30%, as the silica fume content increases, the 28-day compressive strength of the concrete first decreases and then increases, and it is the lowest at 35.3 MPa when the silica fume content is 2.5%. Therefore, when the single fly ash content is between 0 and 35% and the compound admixture ratio of fly ash and silica fume is 25%:5% and 30%:10%, the concrete strength meets the design strength value requirements of C30 concrete.

[0053] To make the workability of the concrete meet the requirements of ultra-long span pumping construction, the pumping performance of the pumped concrete can be efficiently regulated by optimizing the admixture components. The admixture components are compounded from a water-reducing mother liquor, a slump-retention mother liquor, sodium gluconate, sodium tripolyphosphate, a water-retaining agent, an air-entraining agent, and water, etc. The influence of different proportions of the admixture components on the performance of C30 concrete is shown in Figure 11 and Figure 12 It can be found that the admixture components have a significant influence on the workability of the concrete. The fluidity, cohesiveness, and wrapping property of the mixtures in Example 2 and Example 1 are good, and there are no phenomena of material accumulation, segregation, and bleeding. Slight material accumulation occurs in Example 3 and Example 4, and segregation occurs in Example 4. In addition, all the examples meet the design strength value requirements of C30 concrete. Compared with Example 2 of the reference group, reducing the air-entraining agent component content by 0.09% can increase the 28-day compressive strength of the concrete by 17.8%. When the sodium gluconate content is increased by 3% and the air-entraining agent component content is reduced by 0.09%, the 28-day compressive strength of the concrete is increased by 20.8%. When the water-reducing mother liquor, the slump-retention mother liquor, sodium gluconate, sodium tripolyphosphate, the water-retaining agent, and the air-entraining agent are increased by 3%, 3%, 3%, 0.2%, 0.1%, and -0.1% respectively, the 28-day compressive strength of the concrete is increased by 21.0%. Therefore, to meet the pumping requirements, the optimal admixture composition is Example 1.

[0054] Obviously, the above are only some embodiments of the present invention, rather than all embodiments. The above embodiments do not limit the present invention, and various changes and modifications can be made to the present invention by those skilled in the art. Any combination, modification, equivalent replacement, improvement and all other embodiments that can be made by ordinary skilled persons in the art within the spirit and principle of the present invention should fall within the protection scope of the present invention.

Claims

1. A high-performance manufactured sand concrete based on the pumping requirements of a catwalk with an extremely long span, characterized in that: It is made of raw materials including the following mass percentages: 10% - 12% of cement, 3% - 5% of fly ash, 0.5% - 1% of silica fume, 6% - 8% of water, 35% - 40% of manufactured sand, 30% - 50% of 5 - 20mm crushed stone, and 0.1% - 0.3% of admixture; the admixture is made of raw materials including the following mass percentages: 10% - 30% of water - reducing mother liquor, 10% - 30% of slump - retaining mother liquor, 5% - 15% of sodium gluconate, 1% - 3% of sodium tripolyphosphate, 0% - 2% of water - retaining agent, 0% - 0.2% of air - entraining agent, and 30% - 50% of water.

2. The high-performance manufactured-sand concrete based on the pumping requirements of the catwalk with an ultra-long span according to claim 1, characterized in that: The crushed stone is divided into two groups according to the particle sizes of 5 - 10mm and 10 - 20mm, and the mass ratio of the 5 - 10mm crushed stone to the 10 - 20mm crushed stone is 3.5:6.

5.

3. The high-performance manufactured-sand concrete based on the pumping requirements of the ultra-long-span catwalk according to claim 2, wherein: It is made of raw materials including the following mass percentages: 11.08% of cement, 3.96% of fly ash, 0.79% of silica fume, 6.81% of water, 0.19% of admixture, 37.04% of manufactured sand, 12.04% of 5 - 10mm crushed stone, and 28.09% of 5 - 20mm crushed stone; the admixture is made of raw materials including the following mass percentages: 22% of water - reducing mother liquor, 22% of slump - retaining mother liquor, 10% of sodium gluconate, 1.8% of sodium tripolyphosphate, 0.9% of water - retaining agent, 0.1% of air - entraining agent, and 43.2% of water.

4. The high-performance manufactured-sand concrete based on the pumping requirements of the catwalk with an extremely long span according to claim 3, characterized in that: The water-binder ratio of the manufactured sand high-performance concrete is 0.41 to 0.43, the sand ratio is 45 to 50%, and the total amount of binder materials is 360 to 380 kg / m 3 .

5. The high-performance manufactured-sand concrete based on the pumping requirements of a catwalk with an ultra-long span according to claim 4, characterized in that: The sand ratio of the manufactured-sand high-performance concrete is 48%, and the total amount of cementitious materials is 370 kg / m 3 .

6. The preparation method of the high-performance manufactured sand concrete based on the pumping requirements of the ultra-long-span catwalk according to any one of claims 1-5, characterized in that: It includes the following steps: Put cement, fly ash, and silica fume into a mixer according to the ratio, and carry out dry mixing until the admixture is evenly dispersed. Subsequently, add manufactured sand and 5 - 10mm crushed stone and 10 - 20mm crushed stone with a mass ratio of 3.5:6.5 according to the ratio, and continue dry mixing until a uniform aggregate - binder mixture is formed. Divide the water into two parts with a mass ratio of 80%:20% and add them in batches. First, add the mixed solution of 80% mass of water and admixture, stir, and finally add the remaining 20% mass of water and stir to obtain the manufactured - sand high - performance concrete.

Images