Concrete pumping pressure loss calculation method based on Bernoulli equation

Abstract

The invention discloses a Bernoulli equation-based concrete pumping pressure loss calculation method, which comprises the following steps of: firstly, constructing a concrete pumping pressure loss unary flow model based on concrete pumping flow characteristics; secondly, the equivalent diameter and the Reynolds number of a lubricating layer are calculated according to the concrete pumping rheological behavior; a reverse modeling tool is adopted to scan and construct the geometrical shape of the aggregate particles, the equivalent particle size of the non-spherical aggregate particles is obtained through the hydraulic radius, and then the relative roughness of the aggregate particles is calculated; then establishing an energy conversion equation between the two overflowing sections according to fluid state parameters of the overflowing section 1 and the overflowing section 2 by utilizing a Bernoulli equation and a continuity equation, and obtaining a calculation formula of a pressure difference of the two overflowing sections according to the energy conversion equation; and finally, calculating a pressure intensity loss value between the two cutoff surfaces by combining a Mody formula and a Darcy formula. According to the method, the calculation steps are simple, and a theoretical basis is provided for subsequent pump truck design and concrete pumping pressure adjustment.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete pumping, and specifically, it is a method for calculating the pressure loss of concrete pumping based on Bernoulli's equation. Background Art

[0002] The pumping outlet pressure of a concrete pump truck directly affects the concrete conveying distance and its pumping efficiency. The pressure loss during the pumping process is an important reference standard for the design of the pump truck and the regulation of concrete pumping pressure. Studying the pressure loss during the concrete pumping process has always been a key concern in this field.

[0003] Relevant scientific and technological workers at home and abroad have carried out a series of fruitful research works on the rheological characteristics of concrete aggregate particles during the pumping process, including rheological behavior analysis, pumping model construction, and analysis of the influence of pressure loss. At present, most relevant research is based on traditional empirical calculation formulas for concrete pumping pressure loss or uses computer numerical simulation methods to analyze the pressure loss during the concrete pumping process; the pressure loss values calculated by traditional empirical calculation formulas have low accuracy, and the calculated pressure loss values have low reference value for the design of the pump truck and the regulation of concrete pumping pressure; while the computer numerical simulation calculation method, especially the calculation mode combining finite element and discrete element, can accurately simulate the concrete pumping state, but high-precision full-flow field simulation requires a large amount of computing resources, and the calculation cost increases geometrically with the complexity of the model, directly affecting the efficiency of the optimal design of the pump truck pipeline layout. Summary of the Invention

[0004] The purpose of the present invention is to solve the defects existing in the prior art. In view of the above problems, the present invention constructs a one-dimensional flow model of concrete pumping pressure loss based on Bernoulli's equation, and uses Darcy's formula and Moody's formula to calculate the concrete pumping pressure loss value; compared with traditional empirical calculation formulas, the pressure loss value obtained by the present invention has higher accuracy; compared with computer numerical simulation, the calculation steps of the present invention are simple, and the pressure loss value can be deduced using theoretical formulas without the need to consume a large amount of computing resources for numerical simulation analysis; the concrete pumping pressure loss value calculated by the present invention provides a theoretical basis for the subsequent design of the pump truck and the regulation of concrete pumping pressure.

[0005] To achieve the above object, the technical solution adopted by the present invention is a method for calculating the pressure loss of concrete pumping based on the Bernoulli equation. First, based on the flow characteristics of concrete pumping, a one-dimensional flow model of concrete pumping pressure loss is constructed; secondly, according to the rheological behavior of concrete pumping, the equivalent diameter and Reynolds number of the lubricating layer are calculated; then, a reverse modeling tool is used to scan and construct the geometric shape of aggregate particles, and the equivalent diameter of non-spherical aggregate particles is obtained by using the hydraulic radius, and then the relative roughness of aggregate particles is calculated; then, by using the Bernoulli equation and the continuity equation, an energy conversion equation between two cross-sections is established from the fluid state parameters of cross-section 1 and cross-section 2, and then the calculation formula of the pressure difference between the two cross-sections is obtained according to the energy conversion equation; finally, combined with the Moody formula and the Darcy formula, the pressure loss value between the two cross-sections is calculated.

[0006] According to the constructed one-dimensional flow model of concrete pumping pressure loss, as well as the Moody formula, Bernoulli equation and Darcy formula, the pressure loss of concrete pumping is calculated, which specifically includes the following steps:

[0007] Step S101: Based on the flow characteristics of concrete pumping, the concrete flowing in the pump pipe is divided into a plunger layer and a lubricating layer; considering the viscous force of the mortar and the blocking effect of coarse aggregate particles in the lubricating layer, the pressure loss of concrete pumping is mainly concentrated in the lubricating layer area; ignoring the frictional resistance of the pipe wall during concrete pumping, assuming that the critical part between the lubricating layer and the plunger layer is occupied by coarse aggregate particles, and the coarse aggregate particles with different shapes are equivalent to spherical particles with equal particle sizes; according to the above assumptions, a one-dimensional flow model of concrete pumping pressure loss is established with a typical straight pipe as an example, as Figure 1 shown;

[0008] In the figure, v is the concrete pumping flow velocity, l is the length between cross-section 1 and cross-section 2 of the selected control volume, P 1 is the average pressure of cross-section 1, P 2 is the average pressure of cross-section 2; Z 1 is the height of the axis of cross-section 1 from the reference datum plane, Z 2 is the height of the axis of cross-section 2 from the reference datum plane; d is the inner diameter of the pumping pipeline, δ is the thickness of the lubricating layer, K is the equivalent diameter of non-spherical coarse aggregate particles, τ 0 is the viscous force between the lubricating layer and the plunger layer.

[0009] Step S102: Based on the one-dimensional flow model of concrete pumping pressure loss and the rheological behavior of concrete pumping proposed in Step S101, the concrete in the central part of the pump pipe and the mortar around the pipe wall move in the form of a plunger. The lubricating layer is the annular area formed by the pump pipe wall and the plunger layer, and its equivalent diameter is calculated. d e ; Then, according to the calculated equivalent diameter of the lubricating layer, the Reynolds number of the concrete mortar is calculated. R e .

[0010] Step S103: Using the drainage method, randomly select no less than 15 non-spherical coarse aggregate particles, and measure the volume of the non-spherical coarse aggregate. V a ; For non-spherical coarse aggregate particles with complex shapes, use reverse modeling tools to construct the aggregate particle shapes, and utilize the surface area statistics function of 3D drawing software to calculate the total surface area S of the selected non-spherical coarse aggregate particles. a ; According to the formula for calculating the hydraulic radius of spherical coarse aggregate particles in fluid mechanics; let the hydraulic radius of non-spherical coarse aggregate particles be equal to that of spherical particles, and calculate the equivalent diameter of non-spherical coarse aggregate particles. K; Finally, calculate the relative roughness of the aggregate particles according to the calculated equivalent particle size of the non-spherical coarse aggregate particles. K d .

[0011] Step S104: Using Bernoulli's equation and the continuity equation, based on the fluid state parameters of cross-section 1 and cross-section 2, establish an energy conversion equation from cross-section 1 to cross-section 2, and then obtain the calculation formula for the pressure difference between cross-section 1 and cross-section 2 according to the energy conversion equation.

[0012] Step S105: Combine the Moody formula and the Darcy formula to calculate the pressure loss value from cross-section 1 to cross-section 2.

[0013] Furthermore, in Step S101, the concrete in the pump pipe is divided into a lubricating layer and a plunger layer; the entire plunger layer moves along the pump pipe in the form of a plunger flow; due to the viscosity of the concrete, the flow velocity of the lubricating layer in contact with the pump pipe wall is zero, and the flow velocity of the lubricating layer in contact with the plunger layer is the concrete pumping flow velocity; ignoring the frictional resistance of the pipe wall during the concrete pumping process, assuming that the critical part between the lubricating layer and the plunger layer is occupied by coarse aggregate particles, and equivalent the coarse aggregate particles with different shapes to spherical particles with equal particle sizes; and establish a one-dimensional flow model of concrete pumping pressure loss based on the above assumptions.

[0014] Preferably, the calculation formula for the equivalent diameter of the lubricating layer in Step S102 is:

[0015] In the formula, d is the diameter of the pump pipe, δ is the thickness of the lubricating layer.

[0016] And the Reynolds number of the concrete mortar R e The calculation formula is:

[0017] In the formula, u is the dynamic viscosity coefficient of the concrete mortar, K is the equivalent diameter of the non-spherical coarse aggregate particles, and ν is the average flow velocity of the concrete mortar in the lubricating layer.

[0018] And the calculation formula of the dynamic viscosity coefficient of the concrete mortar is:

[0019] In the formula, ρ s is the density of the concrete mortar, T 100 is the time required for the cement paste to slump 100 mm, S 1 is the slump of the mortar.

[0020] Furthermore, the calculation formula for using the drainage method to calculate the total volume of non-spherical coarse aggregate particles in step S103 is:

[0021] In the formula, k is the number of selected non-spherical coarse aggregate particles, V i is the i drainage volume of the V a th non-spherical coarse aggregate particle,

[0022] The calculation formula for the total surface area of the selected non-spherical coarse aggregate particles is:

[0023] In the formula, k is the number of selected non-spherical coarse aggregate particles, S i is the i drainage volume of the S a th non-spherical coarse aggregate particle,

[0024] Preferably, the calculation formula for the equivalent diameter of non-spherical coarse aggregate particles in step S103 is:

[0025] In the formula, V a is the volume of non-spherical aggregate particles, S a is the total surface area of non-spherical aggregate particles.

[0026] The relative roughness of coarse aggregate particles K d The calculation formula is:

[0027] In the formula, K is the equivalent diameter of non-spherical coarse aggregate particles, d e is the equivalent diameter of the lubricating layer.

[0028] Preferably, the calculation formula for the pressure difference between cross-section 1 and cross-section 2 obtained from the energy conversion equation established by the Bernoulli equation and the continuity equation in step S104 is:

[0029] In the formula, h f is the head loss of concrete pumped from cross-section 1 to cross-section 2, γ is the unit weight of concrete mortar, P 1 is the average pressure of cross-section 1, P 2 is the average pressure of cross-section 2; Z 1 is the height of the axis of cross-section 1 from the reference datum, Z 2 is the height of the axis of cross-section 2 from the reference datum.

[0030] Furthermore, the calculation formula for the pressure difference of concrete pumped from cross-section 1 to cross-section 2 in step S105 is:

[0031] In the formula, λ is the friction loss coefficient, d e is the equivalent diameter of the lubricating layer area, ρ s is the density of concrete mortar, P 1 is the average pressure of cross-section 1, P 2 is the average pressure of cross-section 2;Z 1 is the height of the axis of the cross-section of the flowing fluid 1 from the reference datum plane, Z 2 is the height of the axis of the cross-section of the flowing fluid 2 from the reference datum plane, v is the average velocity of the concrete mortar in the lubricating layer.

[0032] The calculation formula for the friction loss coefficient along the way is:

[0033] In the formula, R e is the Reynolds number of the concrete mortar, K d is the relative roughness of the coarse aggregate particles.

[0034] Compared with the prior art, the advantages of the present invention are as follows: starting from the analysis of the rheological behavior of concrete pumping, according to the flow characteristics of concrete in the pump pipe, considering the viscous force of the mortar in the lubricating layer and the blocking effect of the coarse aggregate particles, a one-dimensional flow model of concrete pumping pressure loss is constructed; then, based on the constructed model and combined with the commonly used formulas in fluid mechanics, a calculation method for the concrete pumping pressure loss in a straight pipe pump pipe is obtained; the pressure loss value can be deduced by using the theoretical formula, and there is no need to consume a large amount of computing resources to carry out numerical simulation analysis; the steps are simple, the calculation is convenient, and compared with the traditional empirical calculation formula, the accuracy is higher, which provides a basis for the subsequent pump truck design and concrete pumping pressure regulation. Description of the Drawings

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0036] Figure 1 is a schematic diagram of the one-dimensional flow model of concrete pumping pressure loss.

[0037] Figure 2 is a flowchart of the calculation steps.

[0038] Figure 3 is the three-dimensional geometric reconstruction of non-spherical coarse aggregate particles. Detailed Embodiments

[0039] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the following will clearly and completely describe the technical solutions in the embodiments of this application with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are some, but not all, of the embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts fall within the scope of protection of this application.

[0040] The following further elaborates on the embodiments of the present invention with reference to the accompanying drawings.

[0041] The technical solution adopted by the present invention is a method for calculating the pressure loss of concrete pumping based on the Bernoulli equation. The calculation steps are as Figure 2 follows. First, based on the flow characteristics of concrete pumping, a one-dimensional flow model of concrete pumping pressure loss is constructed. Second, according to the rheological behavior of concrete pumping, the equivalent diameter and Reynolds number of the lubricating layer are calculated. Then, an inverse modeling tool is used to scan and construct the geometric shape of aggregate particles, and the equivalent diameter of non-spherical aggregate particles is obtained using the hydraulic radius, and then the relative roughness of the aggregate particles is calculated. Then, using the Bernoulli equation and the continuity equation, an energy conversion equation is established from the fluid state parameters of the cross-section 1 and cross-section 2 of the flow-through section, and then the calculation formula for the pressure difference between the two cross-sections of the flow-through section is obtained according to the energy conversion equation. Finally, in combination with the Moody formula and the Darcy formula, the pressure loss value between the two cross-sections of the flow-through section is calculated.

[0042] Taking a certain high-rise residential building under construction with 32 floors as the research object, the total height of the building is 100 m. A certain model of truck-mounted pump is used on-site, and the maximum theoretical delivery volume of the pump is 90 m 3 / h, the diameter of the concrete pumping cylinder is 230 mm, the stroke of the delivery cylinder is 1600 mm, the inner diameter of the pumping pipeline is 125 mm, the wall thickness is 10 mm, the elastic modulus is 210 GPa, the Poisson's ratio is 0.3, and the pipeline joints are connected by standard clamps and sealing rings, and are fixed at the reserved holes of each floor slab. The pumping pressure is adjusted according to the construction floor, the minimum pressure is 10 MPa, and the high pressure reaches 20 MPa. The strength grade of the pumped concrete is C30. In this paper, the average flow velocity of the concrete in the delivery pipe is measured to be 0.905 m / s; the average density of the concrete is 2400 kg / m 3 ; the average density of the cement mortar is measured to be 2182 kg / m 3 , standard slump cones are used to sample the concrete and cement mortar in the mixer truck at the construction site, and the average slump S of the concrete is measured to be 210 mm; the average slump S1 of the cement mortar is 230 mm; the time required for the cement mortar to slump 100 mm is about 0.08 s.

[0043] (1)Construct a one-dimensional flow model of concrete pumping pressure loss according to the above situation. In the model, the thickness of the lubricating layer is 3.3 mm; the density of the concrete mortar in the lubricating layer is 2182 kg / m 3 , the flow velocity of the plunger layer in the pump pipe is 0.905 m / s, the flow velocity of the lubricating layer in contact with the pump pipe wall is 0 m / s, and the flow velocity of the lubricating layer in contact with the plunger layer is 0.905 m / s; the inner diameter of the pump pipe d is 125 mm; assuming that the pump pipe is horizontally placed, the height of the axis of the cross-section of the flowing fluid 1 from the reference datum Z 1 is equal to the height of the axis of the cross-section of the flowing fluid 2 from the reference datum Z 2 , that is Z 2 -Z 1 = 0; the length between the cross-section of the control volume 1 and the cross-section of the flowing fluid 2 is selected l to be 1 m.

[0044] (2)From the one-dimensional flow model of concrete pumping pressure loss constructed in (1) and the rheological behavior of concrete pumping, it can be seen that the lubricating layer is an annular area formed by the pump pipe wall and the plunger layer, and its equivalent diameter can be obtained as:

[0045] And the dynamic viscosity coefficient of the concrete mortar is:

[0046] Then the Reynolds number of the concrete mortar can be calculated as:

[0047] (3)Using the drainage method, randomly select 18 non-spherical coarse aggregate particles, and measure the volume of the non-spherical coarse aggregate as:

[0048] In the formula, V i is the drainage volume of the i th non-spherical coarse aggregate particle, V a is the volume of the non-spherical aggregate particle.

[0049] For non-spherical coarse aggregate particles with complex shapes, as shown in Figure 3 , use a HandySCAN non-contact 3D laser scanner and reverse modeling software Geomagic Design X to perform geometric reconstruction on them, and use the geometric surface area statistical function of 3D mapping software to calculate the total surface area of the selected non-spherical coarse aggregate particles as:

[0050] In the formula, S i is the drainage volume of the i th non-spherical coarse aggregate particle, S a is the total surface area of the non-spherical aggregate particles.

[0051] Then the equivalent diameter of the non-spherical coarse aggregate particle is:

[0052] Then the relative roughness of the non-spherical coarse aggregate particle is:

[0053] (4) By using the Bernoulli equation and the continuity equation, based on the fluid state parameters of the flow-through cross-section 1 and the flow-through cross-section 2, an energy conversion equation between the two flow-through cross-sections is established. Then, according to the energy conversion equation, the calculation formula for the pressure difference between the two flow-through cross-sections is:

[0054] In the formula, h f is the head loss of the concrete pumped from the flow-through cross-section 1 to the flow-through cross-section 2, γ is the unit weight of the concrete mortar, P 1 is the average pressure of the flow-through cross-section 1, P 2 is the average pressure of the flow-through cross-section 2; Z 1 is the height of the axis of the flow-through cross-section 1 from the reference datum plane, Z 2 is the height of the axis of the flow-through cross-section 2 from the reference datum plane.

[0055] (5) From the Reynolds number R e of the concrete mortar obtained in (2) and (3) K d and the relative roughness

[0056] of the coarse aggregate particles, combined with the Moody formula, the friction loss coefficient can be obtained as:

[0057] Compared with the pressure loss value Δp = 0.026 Mpa measured in the engineering practice, the pressure loss value calculated theoretically by the present invention is close to the actual value.

[0058] Starting from the analysis of the rheological behavior of concrete pumping, according to the flow characteristics of concrete in the pump pipe, considering the viscous force of the mortar in the lubricating layer and the blocking effect of the coarse aggregate particles, a one-dimensional flow model of concrete pumping pressure loss is constructed; then, based on the constructed model and combined with the commonly used formulas in fluid mechanics, a calculation method for the concrete pumping pressure loss in the straight pipe pump pipe is obtained; to solve the problems that for the concrete in the pumping process, the accuracy of the traditional empirical calculation formula is not high, and although the computer numerical simulation method has high accuracy, the calculation cost increases geometrically with the complexity of the model, affecting the subsequent work efficiency, etc.; the steps are simple, the calculation is convenient, and it has higher accuracy than the traditional empirical calculation formula, providing a basis for the subsequent pump truck design and concrete pumping pressure regulation.

[0059] The above are only specific embodiments of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for calculating the pressure loss of concrete pumping based on Bernoulli's equation, characterized in that, First, based on the pumping flow characteristics of concrete, a one-dimensional flow model of concrete pumping pressure loss is constructed. Secondly, according to the rheological behavior of concrete pumping, the equivalent diameter and Reynolds number of the lubricating layer are calculated. Then, a reverse modeling tool is used to scan and construct the geometric shape of aggregate particles, and the equivalent diameter of non-spherical aggregate particles is obtained using the hydraulic radius, and the relative roughness of aggregate particles is calculated. Then, using the Bernoulli equation and the continuity equation, based on the fluid state parameters of cross-section 1 and cross-section 2, an energy conversion equation from cross-section 1 to cross-section 2 is established, and then the calculation formula for the pressure difference between the two cross-sections is obtained according to the energy conversion equation. Finally, combined with the Moody formula and the Darcy formula, the pressure loss values between the two cross-sections are calculated.

2. The method for calculating the pressure loss of concrete pumping based on the Bernoulli equation according to claim 1, wherein, According to the constructed one-dimensional flow model of concrete pumping pressure loss, as well as the Moody formula, Bernoulli equation and Darcy formula, the pressure loss of concrete pumping is calculated, which specifically includes the following steps: Step S101: Based on the flow characteristics of concrete pumping, the concrete flowing in the pump pipe is divided into a plunger layer and a lubricating layer. Considering the viscous force of the mortar and the blocking effect of the coarse aggregate particles in the lubricating layer, the pressure loss of concrete pumping is mainly concentrated in the lubricating layer area. Ignoring the frictional resistance of the pipe wall during concrete pumping, assuming that the critical part between the lubricating layer and the plunger layer is occupied by coarse aggregate particles, the coarse aggregate particles with different shapes are equivalent to spherical particles with equal particle sizes. Based on the above assumptions, taking a typical straight pipe as an example, a one-dimensional flow model of concrete pumping pressure loss is established: In the straight pipe pump pipe, the thickness of the lubricating layer is δ , and the critical part between the lubricating layer and the plunger layer is occupied by spherical coarse aggregate particles with an equivalent particle size of K ; the flow velocity of the lubricating layer in contact with the pump pipe wall is zero, and the flow velocity of the lubricating layer in contact with the plunger layer is the concrete pumping flow velocity; the entire plunger layer flows along the pump pipe at the pumping speed. Step S102: Based on the one-dimensional flow model of concrete pumping pressure loss and the rheological behavior of concrete pumping proposed in Step S101, the concrete in the central part of the pump pipe and the mortar around the pipe wall move in the form of a plunger. The lubricating layer is the annular area formed by the pump pipe wall and the plunger layer, and its equivalent diameter is calculated d e ; Then, the Reynolds number of the concrete mortar is calculated according to the calculated equivalent diameter of the lubricating layer R e； Step S103: Using the drainage method, randomly extract no less than 15 non-spherical coarse aggregate particles and measure the volume of the non-spherical coarse aggregates V a ; For non-spherical coarse aggregate particles with complex shapes, an inverse modeling tool is used to construct the aggregate particle shapes, and the total surface area S of the selected non-spherical coarse aggregate particles is calculated using the surface area statistical function of the geometric bodies in 3D drawing software. a ; According to the hydraulic radius calculation formula of spherical coarse aggregate particles in fluid mechanics; let the hydraulic radius of non-spherical coarse aggregate particles be equal to that of spherical particles, and calculate the equivalent diameter of non-spherical coarse aggregate particles K； Finally, calculate the relative roughness of aggregate particles according to the equivalent diameter of non-spherical coarse aggregate particles calculated K d； Step S104: Using the Bernoulli equation and the continuity equation, based on the fluid state parameters of cross-section 1 and cross-section 2, an energy conversion equation from cross-section 1 to cross-section 2 is established, and then the calculation formula for the pressure difference between cross-section 1 and cross-section 2 is obtained according to the energy conversion equation. Step S105: Combining the Moody formula and the Darcy formula, calculate the pressure loss value from cross-section 1 to cross-section 2.

3. The pressure loss calculation method based on the one-dimensional flow model of concrete pumping pressure loss according to claim 2, characterized in that In step S101, the concrete in the pump pipe is divided into a lubricating layer and a plunger layer; the plunger layer as a whole moves along the pump pipe in the form of plug flow; due to the viscosity of concrete, the flow velocity of the lubricating layer in contact with the pump pipe wall is zero, and the flow velocity of the lubricating layer in contact with the plunger layer is the concrete pumping flow velocity; ignoring the frictional resistance of the pipe wall during concrete pumping, it is assumed that the critical part between the lubricating layer and the plunger layer is occupied by coarse aggregate particles, and the coarse aggregate particles with different shapes are equivalent to spherical particles with equal particle sizes; and a one-dimensional flow model of concrete pumping pressure loss is established based on the above assumptions.

4. The method for calculating the pressure loss of concrete pumping based on the Bernoulli equation according to claim 2, wherein The calculation formula for the equivalent diameter of the lubricating layer in step S102 is: ； In the formula, d is the diameter of the pump pipe, δ is the thickness of the lubricating layer; The Reynolds number of the concrete mortar R e The calculation formula is as follows: ； In the formula, u is the dynamic viscosity coefficient of the concrete mortar, K is the equivalent diameter of the non-spherical coarse aggregate particles, and ν is the average flow velocity of the concrete mortar in the lubricating layer; And the calculation formula for the dynamic viscosity coefficient of concrete mortar is: ； In the formula, ρ s is the density of the concrete mortar, T 100 is the time required for the cement slurry to slump 100 mm, S 1 is the slump of the mortar.

5. The method for calculating the pressure loss of concrete pumping based on the Bernoulli equation according to claim 2, characterized in that, The calculation formula for using the drainage method to calculate the total volume of non-spherical coarse aggregate particles in step S103 is: ； In the formula, k is the selected number of non-spherical coarse aggregate particles, V i is the i th drained volume of non-spherical coarse aggregate particles, V a is the total volume of non-spherical aggregate particles; The calculation formula for the total surface area of the selected non-spherical coarse aggregate particles is: ； In the formula, k is the selected quantity of non-spherical coarse aggregate particles, S i is the i th drained volume of the non-spherical coarse aggregate particle, S a is the total surface area of the non-spherical aggregate particles.

6. The method for calculating the concrete pumping pressure loss based on the Bernoulli equation according to claim 2, characterized in that, The calculation formula for the equivalent diameter of non-spherical coarse aggregate particles in step S103 is: ； In the formula, V a is the volume of non-spherical aggregate particles, S a is the total surface area of non-spherical aggregate particles; Relative roughness of coarse aggregate particles K d The calculation formula is as follows: ； In the formula, K is the equivalent diameter of non-spherical coarse aggregate particles, d e is the equivalent diameter of the lubricating layer.

7. The method for calculating the pressure loss of concrete pumping based on the Bernoulli equation according to claim 2, characterized in that, The calculation formula for the pressure difference between cross-section 1 and cross-section 2 obtained from the energy conversion equation established by the Bernoulli equation and the continuity equation in step S104 is: ； Wherein, h f is the head loss of concrete pumped from cross-section 1 to cross-section 2, γ is the unit weight of concrete mortar, P 1 is the average pressure of cross-section 1, P 2 is the average pressure of cross-section 2; Z 1 is the height of the axis of cross-section 1 from the reference datum plane, Z 2 is the height of the axis of cross-section 2 from the reference datum plane.

8. The method for calculating the pressure loss of concrete pumping based on the Bernoulli equation according to claim 2, wherein, The calculation formula for the pressure difference when concrete is pumped from cross-section 1 to cross-section 2 in step S105 is: ； Where λ is the coefficient of head loss along the path, d e is the equivalent diameter of the lubricating layer area, ρ s is the density of the concrete mortar, P 1 is the average pressure of the cross-section 1 of the flowing fluid, P 2 is the average pressure of the cross-section 2 of the flowing fluid; Z 1 is the height of the axis of the cross-section 1 from the reference datum plane, Z 2 is the height of the axis of the cross-section 2 from the reference datum plane, v is the average velocity of the concrete mortar in the lubricating layer; And the calculation formula for the coefficient of friction loss is: ； In the formula, R e is the Reynolds number of the concrete mortar, K d is the relative roughness of the coarse aggregate particles.

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