Method for preparing marine concrete with underwater self-flowing cementitious block stone and marine concrete

Abstract

The application relates to a preparation method of marine concrete for underwater self-flowing cemented block stones and marine concrete, and comprises the following steps: obtaining component information of reference concrete; determining the amount of fast-hardening cement for replacing Portland cement according to the expected initial setting time and the expected final setting time of the marine concrete; calculating the maximum particle size and the grading of coarse aggregates in the sandstone aggregate according to the particle size range of the block stones in the block stone accumulation body; calculating the expected flow depth of the block stone accumulation body in water and the expected diffusion diameter of the surface of the block stone accumulation body according to the single pouring amount of the marine concrete and the diameter of the pouring pipe, and determining the expected extension degree of the marine concrete in water; obtaining the component information of the marine concrete; and preparing the marine concrete according to the component information of the marine concrete. The scheme provided by the application can improve the anti-scouring effect of the cemented block stones under the continuous scouring of water flow, so that the flowability of the concrete is good during the pouring process, and the concrete can be quickly solidified after pouring.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of concrete, in particular to a method for preparing marine concrete for underwater self-flowing cemented block stones and marine concrete. BACKGROUND

[0002] Underwater non-dispersible concrete is a new type of concrete, which has underwater anti-dispersibility. Even in underwater engineering with complex water flow conditions, the cement mortar loss rate can be maintained within a low range, ensuring that the concrete can normally set and harden during underwater construction and maintaining good working performance.

[0003] However, underwater non-dispersible concrete has high viscosity, which is not conducive to the mixing and construction of concrete. In related technologies, the flow spread of underwater non-dispersible concrete is generally 450mm±20mm, which leads to poor flow rate of underwater non-dispersible concrete in the block stone accumulation body, making it difficult to form a high-void-ratio cemented block stone body. The quality of the formed underwater non-dispersible concrete is low, which cannot meet the actual construction requirements. SUMMARY

[0004] To solve or partially solve the problems in the related art, the present application provides a method for preparing marine concrete for underwater self-flowing cemented block stones and marine concrete, which can improve the anti-erosion effect of cemented block stones under continuous water flow erosion, so that the concrete has good fluidity during pouring and can quickly set after pouring.

[0005] The first aspect of the present application provides a method for preparing marine concrete for underwater self-flowing cemented block stones, comprising obtaining component information of a reference concrete, the component information comprising: amount of Portland cement, amount of admixture, amount of sand and stone aggregate, amount of water and amount of additive; determining the amount of fast-hardening cement replacing the Portland cement according to the expected initial setting time and the expected final setting time of the marine concrete, the amount of fast-hardening cement replacing the Portland cement being the same as the amount of Portland cement being replaced; calculating the maximum particle size and grading of coarse aggregate in the sand and stone aggregate according to the particle size range of block stones in the block stone accumulation body; calculating the expected flow depth of the block stone accumulation body in water and the expected diffusion diameter of the surface of the block stone accumulation body according to the single pouring amount of the marine concrete and the diameter of the pouring pipe, and determining the expected spread of the marine concrete in water according to the expected flow depth and the expected diffusion diameter; adjusting the component information of the reference concrete according to the amount of fast-hardening cement, the maximum particle size and grading, and the expected spread to obtain the component information of the marine concrete; and preparing the marine concrete according to the component information of the marine concrete.

[0006] In a possible implementation manner of the first aspect, the first fast hardening cement amount is calculated according to the expected initial setting time and the expected final setting time of the marine concrete, and the second fast hardening cement amount is calculated according to the expected initial setting time and the expected final setting time of the marine concrete.

[0007]

[0008] wherein T s is the expected initial setting time, a1, b1 and c1 are coefficients, b1 is greater than 5, T0 is the initial setting time of the concrete when the fast hardening cement amount is 0, and η1 is the first fast hardening cement mixing amount ratio, representing the proportion of the fast hardening cement in the cement, η1 is greater than or equal to 0 and less than or equal to 20%; the second fast hardening cement amount is calculated according to the following formula:

[0009]

[0010] wherein T f is the expected final setting time, a2, b2 and c2 are coefficients, b2 is greater than 10, T1 is the final setting time of the concrete when the fast hardening cement amount is 0, and η2 is the second fast hardening cement mixing amount ratio, representing the proportion of the fast hardening cement in the cement, η2 is greater than or equal to 0 and less than or equal to 20%; the maximum value of the first fast hardening cement amount and the second fast hardening cement amount is taken as the fast hardening cement amount for replacing the Portland cement.

[0011] In a possible implementation manner of the first aspect, the maximum particle size and the gradation of the coarse aggregate in the sandstone aggregate are calculated according to the particle size range of the block stone in the block stone accumulation body, including: extracting a minimum block stone particle size from the block stone particle size range; extracting a minimum particle size ratio and a maximum particle size ratio from a preset particle size ratio range; calculating a first ratio between the minimum block stone particle size and the minimum particle size ratio, and a second ratio between the minimum block stone particle size and the maximum particle size ratio; determining the maximum particle size of the coarse aggregate according to the first ratio and the second ratio, the maximum particle size of the coarse aggregate being between the first ratio and the second ratio.

[0012] In a possible implementation manner of the first aspect, the gradation of the coarse aggregate in the sandstone aggregate is calculated according to the particle size range of the block stone in the block stone accumulation body, including: determining a target particle size of the coarse aggregate corresponding to the gradation according to the first ratio, the target particle size being calculated according to the following formula:

[0013]

[0014] Wherein, St is the target particle size, Sdmin is the minimum particle size of the block stone; the grading of the coarse aggregate is determined as the particle size of the coarse aggregate being greater than or equal to a preset dosage in a range of 5 mm to the target particle size.

[0015] In combination with the first aspect, in a possible implementation manner of the first aspect, the expected flow depth of the block stone accumulation body in water and the expected spread diameter of the surface of the block stone accumulation body are calculated according to the single pouring amount of the marine concrete and the diameter of the pouring pipe, and the expected spread degree of the marine concrete in water is determined according to the expected flow depth and the expected spread diameter, including: the expected spread diameter is calculated by the following formula:

[0016] D s = D t · (K1· (V p ) n + K2)

[0017] Wherein, D s is the expected spread diameter, D t is the diameter of the pouring pipe, K1, n and K2 are coefficients, and V p is the single pouring amount.

[0018] In combination with the first aspect, in a possible implementation manner of the first aspect, the composition information of the reference concrete is adjusted according to the amount of the fast-hardening cement, the maximum particle size and grading, and the expected spread degree, to obtain the composition information of the marine concrete, including: the part of Portland cement corresponding to the amount of the fast-hardening cement in the reference concrete is replaced by the amount of fast-hardening cement; the sand and stone aggregate in the reference concrete is adjusted according to the maximum particle size and grading; the amount of the admixture in the reference concrete is adjusted according to the expected spread degree, and the adjustment amount of the admixture is positively correlated with the expected spread degree.

[0019] The second aspect of the application provides a marine concrete, including 200 to 450 parts of Portland cement, 50-150 parts of fast-hardening cement, 0-300 parts of admixture, 1200 to 2100 parts of sand and stone aggregate, 180 to 220 parts of water, and 7 to 15 parts of admixture; the sand and stone aggregate includes 700 to 1200 parts of fine aggregate and 500 to 900 parts of coarse aggregate.

[0020] In combination with the second aspect, in a possible implementation manner of the second aspect, the fast-hardening cement is sulphoaluminate cement, the admixture includes fly ash and stone powder, and the admixture is alkali water plasticizer.

[0021] With reference to the second aspect, in a possible implementation manner of the second aspect, the coarse aggregate has a content of 60% or more in a particle size range of 2 mm to 10 mm.

[0022] With reference to the second aspect, in a possible implementation manner of the second aspect, the marine concrete has an expansion degree of 550 mm to 700 mm, and a loss rate of the expansion degree of the marine concrete is less than or equal to 15% after 10 minutes of preparation.

[0023] The technical solution provided in the present application can include the following beneficial effects:

[0024] The method for preparing the underwater self-flowing cemented block stone marine concrete and the marine concrete provided in the present application include obtaining component information of a reference concrete, the component information including: an amount of Portland cement, an amount of admixture, an amount of sand and stone aggregate, an amount of water, and an amount of additive; determining an amount of fast-hardening cement for replacing the Portland cement according to an expected initial setting time and an expected final setting time of the marine concrete, the amount of the fast-hardening cement for replacing being the same as an amount of the Portland cement for being replaced; calculating a maximum particle size and a grading of coarse aggregate in the sand and stone aggregate according to a particle size range of the block stone in a block stone accumulation body; calculating an expected flow depth of the block stone accumulation body in water and an expected spread diameter of a surface of the block stone accumulation body according to a single pouring amount of the marine concrete and a diameter of a pouring pipe, and determining an expected expansion degree of the marine concrete in water according to the expected flow depth and the expected spread diameter; adjusting the component information of the reference concrete to obtain component information of the marine concrete according to the amount of the fast-hardening cement, the maximum particle size and the grading, and the expected expansion degree; and preparing the marine concrete according to the component information of the marine concrete, which can improve the anti-scouring effect of the cemented block stone under continuous scouring of water flow, make the concrete have good flowability during pouring, and enable the concrete to be quickly solidified after pouring.

[0025] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory and are not restrictive of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0026] The above and other objects, features and advantages of the present application will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which like reference characters refer to like parts throughout and in which:

[0027] Figure 1 FIG. 1 is a flowchart of a method for preparing underwater self-flowing cemented block stone marine concrete according to an embodiment of the present application. DETAILED DESCRIPTION

[0028] Embodiments of the present application will be described in more detail with reference to the drawings. Although the embodiments of the present application are shown in the drawings, it is understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the application to those skilled in the art.

[0029] The terminology used in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used in the description of the application and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0030] It should be understood that although the terms "first", "second", "third", etc. can be employed in this application to describe various information, such information should not be limited by these terms. These terms are only used to distinguish one piece of information from another piece of information. For example, a first information can also be referred to as a second information, and similarly, a second information can also be referred to as a first information, without departing from the scope of the present application. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0031] There are two kinds of concrete used for underwater construction at present, one is underwater non-dispersible concrete, which is prepared by ordinary concrete and anti-dispersible agent (flocculating agent). The anti-dispersible agent is usually a water-soluble polymer, which has a certain viscosity after dissolving in water due to the bridging effect of the long molecular chain, so as to connect the cement particles and cement particles-aggregate particles together to form a stable spatial flexible network structure, thereby improving the cohesion of the concrete and slowing down the dispersion, segregation and cement mortar loss of the concrete. That is, by adding flocculating agent (underwater non-dispersible agent) to the concrete, the viscosity of the concrete is increased, so that it has the ability to resist dispersion underwater. The other is underwater self-protecting concrete, which is prepared by first pouring underwater protective agent into the construction water body to modify the water body, and then pouring self-compacting concrete. The modified water body can inhibit the loss of cementitious materials in the self-compacting concrete, thereby achieving the effect of underwater dispersion resistance. These two kinds of concrete have great differences in performance and mix proportion.

[0032] The underwater non-dispersive concrete has high viscosity, which is not conducive to the mixing and construction of the concrete, and the flow spread is generally 450mm±20mm, which leads to poor flow rate of the underwater non-dispersive concrete in the stone accumulation body under water, and the underwater non-dispersive concrete cannot meet the flow of the concrete in the stone accumulation body under the complex marine environment, and it is difficult to achieve the purpose of forming the high-void-ratio cemented stone body.

[0033] To solve the above problems, the embodiment of the present application provides a method for preparing underwater self-flowing cemented stone marine concrete, which can improve the anti-erosion effect of the cemented stone under continuous water flow scouring, so that the concrete has good flowability during pouring, and can quickly solidify after pouring.

[0034] The technical solutions of the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0035] Figure 1 is a flowchart of the method for preparing underwater concrete shown in the embodiments of the present application.

[0036] Referring to Figure 1 , a method for preparing underwater self-flowing cemented stone marine concrete, comprising:

[0037] S110: Obtain the component information of the reference concrete, the component information including the amount of Portland cement, the amount of admixture, the amount of sand and gravel aggregate, the amount of water and the amount of additive.

[0038] Specifically, the reference concrete is the concrete to be prepared, and the amount of Portland cement, the amount of admixture, the amount of sand and gravel aggregate, the amount of water and the amount of additive are calculated respectively to prepare the reference concrete. The reference concrete has relevant component information, that is, the reference concrete is prepared by the predetermined amount of Portland cement, the amount of admixture, the amount of sand and gravel aggregate, the amount of water and the amount of additive during the preparation of the reference concrete. For example, the component information of the reference concrete can be Portland cement: 350kg / m 3 , admixture: 100kg / m 3 , fine sand: 700kg / m 3 , sand and gravel aggregate: 1200kg / m 3 , water: 175kg / m 3 , additive: 2kg / m 3 .

[0039] Specifically, Portland cement is a common building material, mainly by limestone and clay calcined at high temperature, then add the right amount of gypsum (usually 2% to 5%) ground into, Portland cement usually accounts for 10% to 15% of the total volume of concrete; admixture refers to the addition of auxiliary materials in the production process of cement or when using cement, which can partially replace cement, such as fly ash, slag powder, silica fume, limestone powder, etc., usually accounts for 10% to 30% of the amount of cement; sand and gravel aggregate is the largest component of concrete, which provides volume, shape and structure for concrete, usually accounts for 30% to 40% of the total volume of concrete, sand and gravel aggregate is generally divided into two categories, fine aggregate mainly refers to sand, including river sand, sea sand, mountain sand and artificial sand, etc. The particle size of fine aggregate is usually less than 4.75 mm, and the fine aggregate fills the gap between the coarse aggregate, providing the density and strength of the concrete. Coarse aggregate mainly includes gravel, broken bricks, broken concrete and other hard material blocks, with particle size usually greater than 4.75 mm, up to 20 mm, 40 mm or other sizes, which plays a role in the framework of concrete and affects the overall structure and mechanical properties of concrete; admixtures are used during the mixing process of concrete to improve the performance of concrete or provide specific functions, such as water reducing agent, retarder, early strength agent, etc., which can improve the performance of concrete.

[0040] S120: determining the amount of fast-hardening cement to replace Portland cement according to the expected initial setting time and the expected final setting time of marine concrete, the amount of fast-hardening cement to replace and the amount of Portland cement to be replaced are the same.

[0041] Specifically, the amount of fast-hardening cement can be determined by calculation according to actual needs, and the amount of Portland cement to be replaced can be obtained. During the pouring process, the amount of Portland cement to be replaced is replaced by fast-hardening cement, for example, the amount of fast-hardening cement to be replaced accounts for 20% of the total amount of cement, which can improve the fluidity of concrete during the pouring process.

[0042] In one possible implementation, the first fast-hardening cement amount is calculated by the following formula:

[0043]

[0044] wherein T s is the expected initial setting time, a1, b1 and c1 are coefficients, b1 is greater than 5, T0 is the initial setting time of concrete when the amount of fast-hardening cement is 0, η1 is the first fast-hardening cement content ratio, indicating the proportion of fast-hardening cement in cement, η1 is greater than or equal to 0 and less than or equal to 20%;

[0045] The second fast-hardening cement amount is calculated by the following formula:

[0046]

[0047] wherein, T f is the expected final setting time, a2, b2 and c2 are coefficients, b2 is greater than 10, T1 is the final setting time of the concrete when the amount of the fast-hardening cement is 0, η2 is the second fast-hardening cement content ratio, indicating the proportion of the fast-hardening cement in the cement, η2 is greater than or equal to 0 and less than or equal to 20%; the maximum value between the first fast-hardening cement amount and the second fast-hardening cement amount is taken as the fast-hardening cement amount of the replacement Portland cement.

[0048] Specifically, in the formula for calculating the first fast-hardening cement amount, the initial setting time of the concrete without mixing the fast-hardening cement in the pouring process is directly obtained, denoted as T0, and the values of a1, b1 and c1 are set according to actual needs, and the expected initial setting time is set according to the actual working condition, denoted as T s , and the value of the first fast-hardening cement amount η1 is calculated according to the formula; in the formula for calculating the second fast-hardening cement amount, the final setting time of the concrete without mixing the fast-hardening cement in the pouring process is directly obtained, denoted as T1, and the values of a2, b2 and c2 are set according to actual needs, and the expected final setting time is set according to the actual working condition, denoted as T f , and the value of the second fast-hardening cement amount η2 is calculated according to the formula, after the first fast-hardening cement amount and the second fast-hardening cement amount are calculated, the maximum value between the two is taken as the fast-hardening cement amount of the replacement Portland cement, and the fast-hardening cement content is quickly determined according to the formula, which not only ensures that the fluidity (spread) of the concrete in the pouring process produces a small loss, but also ensures the rapid setting of the concrete after pouring, avoiding the weakening of the cementation effect of the cemented blocks under the continuous erosion of the water flow.

[0049] S130: According to the block stone particle size range in the block stone accumulation body, the maximum particle size and the grading of the coarse aggregate in the sandstone aggregate are calculated.

[0050] Specifically, the block stone accumulation body is usually a special form of concrete using large block stones as aggregate in the concrete structure, and the particle sizes of the block stones in the block stone accumulation body can all be different and within an interval range, for example, the block stone particle size can be between 10 cm-20 cm, and the grading refers to the particle size and distribution of the aggregate (including fine aggregate and coarse aggregate). Through the block stone particle size range, the maximum particle size and the grading of the coarse aggregate in the sandstone aggregate can be calculated.

[0051] In one possible implementation, the minimum block stone particle size is extracted from the block stone particle size range; the minimum particle size ratio and the maximum particle size ratio are extracted from the preset particle size ratio range; the first ratio between the minimum block stone particle size and the minimum particle size ratio, and the second ratio between the minimum block stone particle size and the maximum particle size ratio are calculated; according to the first ratio and the second ratio, the maximum particle size of the coarse aggregate is determined, and the maximum particle size of the coarse aggregate is between the first ratio and the second ratio.

[0052] Specifically, the minimum particle size of the block stone can be obtained from the block stone to be poured, and the minimum particle size of the block stone can be 5-10 times the maximum particle size of the coarse aggregate, for example, the minimum particle size of the block stone is 10 cm. The minimum particle size ratio can be the percentage of the minimum particle size of the block stone in the total block stone. The maximum particle size ratio is the percentage of the maximum particle size of the block stone in the total block stone. The first ratio between the minimum particle size of the block stone and the minimum particle size ratio can be calculated, for example, the minimum particle size of the block stone is 10 cm, and the minimum particle size ratio of the block stone is 20%. The second ratio between the minimum particle size of the block stone and the maximum particle size ratio can be calculated, for example, the minimum particle size of the block stone is 10 cm, and the minimum particle size ratio of the block stone is 30%. According to the first ratio and the second ratio, the range of the maximum particle size of the coarse aggregate can be determined.

[0053] In one possible implementation, according to the first ratio, the target particle size of the coarse aggregate corresponding to the grading is determined, and the target particle size is calculated by the following formula:

[0054]

[0055] wherein S t is the target particle size, S dmin is the minimum particle size of the block stone, which can be obtained from the block stone accumulation body. The grading of the coarse aggregate is determined as follows: the content of the particle size of the coarse aggregate in the range of 5 mm to the target particle size is greater than or equal to a preset content, and the preset content can be 60%. According to the formula, the maximum particle size and the grading of the coarse aggregate in the marine concrete are quickly determined by the particle size of the block stone, so that the concrete can expand to the expected range on the surface of the block stone accumulation body and flow to the expected depth, thereby forming a cemented riprap cluster meeting the design requirements.

[0056] S140: According to the single pouring amount of the marine concrete and the diameter of the pouring pipe, the expected flow depth of the block stone accumulation body in water and the expected diffusion diameter of the surface of the block stone accumulation body are calculated, and the expected expansion degree of the marine concrete in water is determined according to the expected flow depth and the expected diffusion diameter.

[0057] Specifically, during the pouring process, the single pouring amount of the marine concrete and the diameter of the pouring pipe can be preset, and the expected flow depth and the expected diffusion diameter of the block stone accumulation body in water can be calculated. The flow depth refers to the maximum thickness of the concrete on the horizontal surface when it freely flows or pours from a certain height under the action of gravity. The diffusion diameter is the maximum diameter to which the concrete flows and diffuses under certain conditions. According to the expected flow depth and the expected diffusion diameter, the expected expansion degree of the marine concrete in water can be calculated, for example, the expansion degree is 550-700 mm.

[0058] In one possible implementation, the expected diffusion diameter is calculated by the following formula:

[0059] Ds = D t (K1·(V p ) n +K2)

[0060] wherein, D s is the expected diffusion diameter, D t is the diameter of the pouring pipe, K1, n and K2 are coefficients which can be set according to actual needs, V p is the single pouring amount,

[0061] The expected spread is determined according to the expected flow depth and the expected diffusion diameter, and the expected spread is positively correlated with the expected flow depth and the expected diffusion diameter.

[0062] S150: adjusting the component information of the reference concrete according to the amount of fast-hardening cement, the maximum particle size and grading of the coarse aggregate, and the expected spread, to obtain the component information of the marine concrete, and preparing the marine concrete according to the component information of the marine concrete.

[0063] Specifically, the required amount of fast-hardening cement, the maximum particle size and grading of the coarse aggregate, and the expected spread are calculated by the formula, the component information of the reference concrete is modified, and the marine concrete is prepared according to the modified component information, so that the concrete can spread to the expected range on the surface of the rock pile body and flow to the expected depth, forming a cemented riprap cluster meeting the design requirements, and different design requirements can be met for different working conditions to ensure the construction quality, such as offshore wind power pile foundation or offshore cable protection projects, etc. If the particle size of the thrown and filled rock is too large, the submarine optical cable and other submarine facilities are easy to be damaged, and if the particle size is too small, the throwing and filling precision and protection effect are poor. Through the relationship between the concrete and the cemented rock, the required concrete mix proportion can be directly determined according to the protection rock particle size, the efficiency is improved, and the engineering quality is ensured.

[0064] The method for preparing the underwater self-flowing cemented block stone marine concrete comprises the following steps: obtaining component information of a reference concrete, the component information comprising: amount of Portland cement, amount of admixture, amount of sand and stone aggregate, amount of water and amount of additive; determining amount of fast-hardening cement for replacing the Portland cement according to expected initial setting time and expected final setting time of the marine concrete, the amount of the fast-hardening cement for replacing being equal to the amount of the Portland cement being replaced; calculating maximum particle size and grading of coarse aggregate in the sand and stone aggregate according to particle size range of the block stone in the block stone accumulation body; calculating expected flow depth of the block stone accumulation body in water and expected spread diameter of the surface of the block stone accumulation body according to single pouring amount of the marine concrete and diameter of a pouring pipe, and determining expected spread degree of the marine concrete in water according to the expected flow depth and the expected spread diameter; adjusting the component information of the reference concrete according to the amount of the fast-hardening cement, the maximum particle size and the grading and the expected spread degree to obtain component information of the marine concrete; and preparing the marine concrete according to the component information of the marine concrete, so that the anti-scouring effect of the cemented block stone under continuous scouring of water flow is improved, the flowability of the concrete is good during pouring, and the concrete can be quickly solidified after pouring.

[0065] Corresponding to the example of the method for preparing the underwater concrete, the application further provides a marine concrete and corresponding examples.

[0066] The marine concrete comprises: 200 to 450 parts of Portland cement, 50-150 parts of fast-hardening cement, 0-300 parts of admixture, 1200 to 2100 parts of sand and stone aggregate, 180 to 220 parts of water and 7 to 15 parts of additive, each part being the weight required for unit volume.

[0067] In a possible implementation, the fast-hardening cement is sulphoaluminate cement, the admixture comprises fly ash and stone powder, and the additive is alkali water plasticizer.

[0068] In a possible implementation, the content of the coarse aggregate with a particle size of 2 mm to 10 mm is greater than or equal to 60%.

[0069] In a possible implementation, the spread degree of the marine concrete is 550 mm to 700 mm, and the loss rate of the spread degree of the marine concrete after being prepared for ten minutes is less than or equal to 15%.

[0070] In order to make the application easier to understand, the application will be further described in detail below in combination with examples, which are only illustrative and do not limit the application. The raw materials or components used in the application can be prepared by commercial channels or conventional methods if not specifically stated.

[0071] Example 1

[0072] The component information of the marine concrete is as follows:

[0073] Cement: ordinary Portland cement (P.O 42.5), 475 kg;

[0074] Fast-hardening cement: sulphoaluminate cement (RC.SAC 42.5), 125 kg;

[0075] Fine aggregate: river sand, 834 kg;

[0076] Coarse aggregate: 5-25 mm full-graded gravel, 682 kg;

[0077] Water: 207 kg;

[0078] Admixture: retarding polycarboxylic type water reducing agent, 13.1.

[0079] The preparation method is as follows: the cement, the fast-hardening cement and the admixture are mixed to obtain a mixture; the fine aggregate and the coarse aggregate are added to the mixture to obtain a mixed material; and the water is added to the mixed material and mixed for 2 min to obtain the marine concrete.

[0080] The marine concrete prepared according to the above formula has the following properties: machine extension degree: 650 mm, 10 min extension degree: 570 mm, initial setting time: 42 min, final setting time: 53 min, 1 d compressive strength: 9.4 MPa, and 28 d compressive strength: 44.5 MPa. The marine concrete prepared has high compressive strength and the extension degree meets the expected range, thereby ensuring the construction quality.

[0081] Example Two

[0082] The component information of the marine concrete is as follows:

[0083] Cement: ordinary Portland cement (P.O 42.5), 350 kg;

[0084] Fast-hardening cement: sulphoaluminate cement (RC.SAC 42.5), 57 kg;

[0085] Mixture: 200-mesh stone powder, 100 kg;

[0086] Fine aggregate: river sand, 1073 kg;

[0087] Coarse aggregate: 5-10 mm gravel, 216 kg, and 5-20 mm gravel, 324 kg;

[0088] Water: 150 kg;

[0089] Admixture: retarding polycarboxylic type water reducing agent, 10.47.

[0090] The preparation method is as follows: mixing formula amount of cement, fast hardening cement and admixture to obtain a mixture; adding fine aggregate and coarse aggregate to the mixture to obtain a mixed material; adding water to the mixed material and mixing for 2 minutes to obtain the marine concrete.

[0091] The marine concrete prepared according to the above formula has the following performances: 600mm of machine expansion degree, 550mm of 30min expansion degree, 120min of initial setting time, 180min of final setting time, 8MPa of 3d compressive strength and 30MPa of 28d compressive strength.

[0092] The above has described various embodiments of the present application, the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those skilled in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical application or improvement of technology in the market, or to enable other ordinary skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method of preparing a marine concrete for underwater self-flowing block stone, characterized by, The method comprises the following steps: obtaining component information of a reference concrete, the component information comprising: an amount of Portland cement, an amount of admixture, an amount of sand and stone aggregate, an amount of water, and an amount of additive; determining an amount of quick-hardening cement for replacing the Portland cement according to an expected initial setting time and an expected final setting time of marine concrete, the amount of quick-hardening cement for replacement being the same as the amount of Portland cement to be replaced; calculating a maximum particle size and a gradation of coarse aggregate in the sand and stone aggregate according to a particle size range of rock blocks in a rock block accumulation body; calculating an expected flow depth of the rock block accumulation body in water and an expected spread diameter of a surface of the rock block accumulation body according to a single pouring amount of the marine concrete and a diameter of a pouring pipe, and determining an expected spread degree of the marine concrete in water according to the expected flow depth and the expected spread diameter; adjusting the component information of the reference concrete according to the amount of quick-hardening cement, the maximum particle size and the gradation, and the expected spread degree, to obtain component information of the marine concrete, and preparing the marine concrete according to the component information of the marine concrete; the step of calculating the maximum particle size and the gradation of the coarse aggregate in the sand and stone aggregate according to the particle size range of the rock blocks in the rock block accumulation body comprises: extracting a minimum particle size of the rock blocks from the particle size range of the rock blocks; extracting a minimum particle size ratio and a maximum particle size ratio from a preset particle size ratio range; calculating a first ratio between the minimum particle size of the rock blocks and the minimum particle size ratio, and a second ratio between the minimum particle size of the rock blocks and the maximum particle size ratio; determining the maximum particle size of the coarse aggregate according to the first ratio and the second ratio, the maximum particle size of the coarse aggregate being between the first ratio and the second ratio.

2. The method of claim 1, wherein, the step of determining the amount of quick-hardening cement for replacing the Portland cement according to the expected initial setting time and the expected final setting time of the marine concrete comprises: calculating a first amount of quick-hardening cement by the following formula: wherein, is the expected initial setting time, , and are coefficients, , and are values set according to actual needs, is greater than 5, is the initial setting time of the concrete when the amount of the fast-hardening cement is 0, is the first fast-hardening cement mixing amount ratio, indicating the proportion of the fast-hardening cement in the cement, is greater than or equal to 0 and less than or equal to 20%. calculating a second amount of quick-hardening cement by the following formula: wherein, is the expected final setting time, , and are coefficients, , and are values set according to actual needs, is greater than 10, is the final setting time of the concrete when the amount of the fast-hardening cement is 0, is the second fast-hardening cement mixing amount ratio, indicating the proportion of the fast-hardening cement in the cement, is greater than or equal to 0 and less than or equal to 20%. taking the maximum value between the first amount of quick-hardening cement and the second amount of quick-hardening cement as the amount of quick-hardening cement for replacing the Portland cement.

3. The method of claim 1, wherein, the step of calculating the gradation of the coarse aggregate in the sand and stone aggregate according to the particle size range of the rock blocks in the rock block accumulation body comprises: calculating a target particle size by the following formula: wherein, is the target particle size, the is the minimum particle size of the rock blocks; determining the gradation of the coarse aggregate to be greater than or equal to a preset amount of the coarse aggregate with a particle size of 5 mm to the target particle size.

4. The method according to any one of claims 1 to 3, characterized in that, the step of calculating the expected flow depth of the rock block accumulation body in water and the expected spread diameter of the surface of the rock block accumulation body according to the single pouring amount of the marine concrete and the diameter of the pouring pipe, and determining the expected spread degree of the marine concrete in water according to the expected flow depth and the expected spread diameter comprises: calculating the expected spread diameter by the following formula: wherein, is the expected diffusion diameter, the is the diameter of the pouring pipe, the , n and is a coefficient, , n and The values of the above parameters are set according to actual needs, is the single pouring amount.

5. The method according to any one of claims 1 to 3, characterized in that, the step of adjusting the component information of the reference concrete according to the amount of quick-hardening cement, the maximum particle size and the gradation, and the expected spread degree to obtain the component information of the marine concrete comprises: replacing a part of the Portland cement in the reference concrete corresponding to the amount of quick-hardening cement with the amount of quick-hardening cement of the quick-hardening cement. Adjusting sand and stone aggregates in the reference concrete according to the maximum particle size and the gradation; Adjusting the admixture in the reference concrete according to the expected expansion, and the adjustment amount of the admixture is positively correlated with the expected expansion.

6. A marine concrete obtainable by the method according to any one of claims 1 to 5, characterized in that Comprise: 200-450 parts of Portland cement, 50-150 parts of fast hardening cement, 0-300 parts of admixture, 1200-2100 parts of sand and stone aggregates, 180-220 parts of water, and 7-15 parts of admixture; The sand and stone aggregates comprise 700-1200 parts of fine aggregates and 500-900 parts of coarse aggregates.

7. Marine concrete according to claim 6, c h a r a c t e r i z e d in that The fast hardening cement is sulphoaluminate cement, the admixture comprises fly ash and stone powder, and the admixture is water-reducing plasticizer.

8. Marine concrete according to claim 7, c h a r a c t e r i z e d in that The coarse aggregates have a content greater than or equal to 60% at a particle size of 2-10 mm.

9. Marine concrete according to claim 6, c h a r a c t e r i z e d in that The expansion of the marine concrete is 550-700 mm, and the loss rate of the expansion of the marine concrete is less than or equal to 15% ten minutes after preparation.

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