### Prediction on pipe flow of pumped concrete based on shear ...

Oct 01, 2013 In the pipe flow of pumped concrete, the shear stress is the highest at the wall of the pipe and linearly decreases as the position moves to the center of the pipe. The stress gradient is a driving force to move particles toward the center of the pipe

Get price### Prediction on pipe flow of pumped concrete based on shear ...

In order to predict the pumping performance, it needs to find the properties of the layer, such as its rheological properties and thickness. A possible mechanism that contributes to the formation of the layer is the shear-induced particle migration. In this study, the pipe flow of pumped concrete was numerically simulated based on its mechanism.

Get price### DSpace at KOASAS: Prediction on pipe flow of pumped ...

Prediction on pipe flow of pumped concrete based on shear-induced particle migration. Cited 49 time in Cited 0 time in . Hit : 319; Download : 0; Export. DC(XML) Excel. Choi, Myoung-Sung / Kim, Young Jin / Kwon, Seung Hee ...

Get price### Assessment and prediction of concrete flow and pumping ...

Mar 01, 2020 Concrete flow in a pipeline is a complex material response to the induced pressure accompanied by shear in LL [], friction between solid particles and pipe wall [10,18,19], and significant hydrodynamic interactions among particles within the partially sheared concrete bulk [20,21]; cf. Fig. 2.The extent to which frictional resistance is active depends on the state of saturation of the concrete ...

Get price### Prediction of Concrete Pumping: Part I—Development of New ...

To predict flow rates of concrete transported by pumping, it is necessary to measure the rheological properties of the lubricating layer before pumping. In this paper, a new version of a test instrument called a tribometer is developed by considering the level of shear rate that induces the lubricating layer during real pumping.

Get price### Effect of the coarse aggregate size on pipe flow of pumped ...

Sep 15, 2014 The objective of this study is to find the influence of the coarse aggregate size on pipe flow of pumped concrete. Six different concrete mixes having two mixture proportions (24 and 50 MPa) and three maximum coarse aggregate sizes (10, 20 and 25 mm) were selected and pumped into 170 m and 1000 m pipelines at different pumping pressures.The rheological properties of the concrete and

Get price### Vol.8, No.4, pp.269–278, December 2014 DOI 10.1007/s40069 ...

properties of lubrication layer and the pipe ﬂow of pumped concrete. 2. Analysis Method for the Pipe Flow of Pumped Concrete 2.1 Shear-Induced Particle Migration As stated in the introduction, to predict the pipe ﬂow of pumped concrete, the lubrication layer should be carefully investigated. Several possible mechanisms illustrating the

Get price### Prediction of Concrete Pumping: Part I—Development of New ...

To predict flow rates of concrete transported by pumping, it is necessary to measure the rheological properties of the lubricating layer before pumping. In this paper, a new version of a test instrument called a tribometer is developed by considering the level of shear rate that induces the lubricating layer during real pumping.

Get price### Effect of the Mineral Admixtures on Pipe Flow of Pumped ...

termine the pipe flow of pumped concrete, were quanti-tatively analyzed. 2. Analytical method of pumped concrete The analytical equation developed by previous study (Choi et al. 2014) which calculates the concrete flow rate and required pressure was adopted to compare with experimental results of full scale pumping test. Here, to

Get price### Seung Hee Kwon - Google Scholar

Prediction on pipe flow of pumped concrete based on shear-induced particle migration. MS Choi, YJ Kim, SH Kwon. Cement and Concrete Research 52, 216-224, 2013. 69: 2013: Prediction of concrete pumping: Part II-Analytical prediction and experimental

Get price### S. KWON Myongji University, Seoul Civil engineering

Prediction on pipe flow of pumped concrete based on shear-induced particle migration ... To accurately estimate the temperature effects on autogenous shrinkage of concrete, a new prediction

Get price### Pumping of Fresh Concrete: Insights and Challenges

formed in front of the concrete, is based on the friction principle [12, 14-15]. If the concrete transitions from a suspension into a soil-like material in a small section of the pipes, it may block the entire line. 3.2 Flow regime Assuming concrete is a suspension, to predict pumping pressure, it is essential to know in which regime concrete is

Get price### Pumping Performance Analysis on Crushed Sand Concrete

[1] Myoung Sung Choi, Seung Hee Kwon, Prediction on pipe flow of pumped concrete based on shear-induced particle migration,Cement and Concrete Research,2013,52, pp.216-224. [2] Jian XU, Ji-Wei CAI, Ji-Liang WANG, Research status of crush sand and concrete [J]. Building Materials Abroad, 2004, 25(3), pp: 20-24.

Get price### Pipe Flow Calculator Hazen–Williams Equation

Aug 23, 2021 The hydraulic radius, R, is the proportion between the area and the perimeter of your pipe. If the pipe is circular, you will find it according to the following equation: R = A / P = πr² / 2πr = r / 2 = d / 4. where r is the pipe radius, and d is the pipe diameter. You can view and modify all these parameters (area, perimeter, hydraulic radius) in the advanced mode of this pipe flow calculator.

Get price### Free Online Manning Pipe Flow Calculator - HawsEDC

Notes: This is the flow and depth inside the pipe. Getting the flow into the pipe may require significantly higher headwater depth. Add at least 1.5 times the velocity head to get the headwater depth or see my 2-minute tutorial for standard culvert headwater calculations using HY-8.. Please give us your valued words of suggestion or praise.

Get price### Pipe Flow Calculations - Clarkson University

fully developed, incompressible, Newtonian flow through a straight circular pipe. Volumetric flow rate . 2 4 Q DV π = where D is the pipe diameter, and V is the average velocity. Reynolds Number: 44 Re DV DV Q m DD ρ µ ν πν π µ = = = = where . ρ is the density of the fluid, µ is its dynamic viscosity, and ν µρ= /

Get price### Friction Factor for Turbulent Pipe Flow

the pipe, D is the diameter of the pipe, u is the velocity of the flow of liquid and g is the acceleration due to the gravity. The friction factor (λ ) is a measure of the shear stress (or shear force per unit area) that the turbulent flow exerts on the wall of a pipe; it is

Get price### Effect of the Mineral Admixtures on Pipe Flow of Pumped ...

The objective of this study is to investigate the effect of the mineral admixtures on pipe flow of pumped concrete through analyzing the properties of lubrication layer playing a dominant role to facilitate concrete pumping. Concrete mixtures incorporating blast furnace slag (BFS), fly ash (FA) and silica fume (SF) were selected with three different replacement ratios for each case and pumped ...

Get price### Report No. K-TRAN: KSU-14-2 Best Practices for Concrete ...

pumpability and how pumping changes concrete properties. A three-phase research study was carried out to (1) investigate performance of pumped concrete in field conditions, (2) identify concrete properties affecting pumpability, and (3) assess the effects of pumping on the concrete air void system. In the first phase of the

Get price### Metrology Needs for Predicting Concrete Pumpability

Jun 22, 2015 2.2. Slip-Layer. Several research groups have investigated the slip-layer of concrete flow in a pipe. Choi et al. [5, 6] measured the thickness of the slip-layer using an Ultrasonic Velocity Profiler (UVP) in pumping circuits using industrial equipment and found that there is a 2 mm thick layer along the inner surface of the pipe.However, the layer thickness could vary depending on the mixture ...

Get price### Vol.8, No.4, pp.269–278, December 2014 DOI 10.1007/s40069 ...

properties of lubrication layer and the pipe ﬂow of pumped concrete. 2. Analysis Method for the Pipe Flow of Pumped Concrete 2.1 Shear-Induced Particle Migration As stated in the introduction, to predict the pipe ﬂow of pumped concrete, the lubrication layer should be carefully investigated. Several possible mechanisms illustrating the

Get price### S. KWON Myongji University, Seoul Civil engineering

Prediction on pipe flow of pumped concrete based on shear-induced particle migration ... To accurately estimate the temperature effects on autogenous shrinkage of concrete, a new prediction

Get price### Pumping Performance Analysis on Crushed Sand Concrete

[1] Myoung Sung Choi, Seung Hee Kwon, Prediction on pipe flow of pumped concrete based on shear-induced particle migration,Cement and Concrete Research,2013,52, pp.216-224. [2] Jian XU, Ji-Wei CAI, Ji-Liang WANG, Research status of crush sand and concrete [J]. Building Materials Abroad, 2004, 25(3), pp: 20-24.

Get price### Jacking Concrete Pipe

above the tunnel, to prevent the flow of ground water along the outside of the tunnel, and provide complete pipe-soil interaction at the invert of the pipe. A typical installation for jacking concrete pipe is shown in Figure 1. LOADS ON JACKED PIPE A concrete pipe installed by jacking is subject-ed simultaneously to axial and transverse forces. For

Get price### Friction Factor for Turbulent Pipe Flow

the pipe, D is the diameter of the pipe, u is the velocity of the flow of liquid and g is the acceleration due to the gravity. The friction factor (λ ) is a measure of the shear stress (or shear force per unit area) that the turbulent flow exerts on the wall of a pipe; it is

Get price### Pipe Friction Loss Calculations - Pipe Flow Software

Pipe Flow Software » Pipe Pressure Drop Calculations » Pipe Friction Loss Flow of fluid through a pipe is resisted by viscous shear stresses within the fluid and the turbulence that occurs along the internal pipe wall, which is dependent on the roughness of the pipe material.

Get price### Non-Newtonian Fluid Math

In pipe flow the things one generally knows (i.e. that can be measured) are the pressure drop Δ𝑃𝑃 for a section of pipe with length 𝐿𝐿 and diameter 𝐷𝐷, and the total volumetric flow rate 𝑉𝑉̇. (In this document we express Δ𝑃𝑃 as a positive quantity, meaning upstream pressure minus downstream pressure.)

Get price### The Manning Equation for Partially Full Pipe Flow Calculations

For S.I. units, the constant in the Manning equation changes slightly to the following: Q = (1.00/n)A(Rh 2/3)S1/2 (2) Where: • Q is the volumetric flow rate passing through the channel reach in m3s. • A is the cross-sectional area of flow normal to the flow direction in m2. • S is the bottom slope of the channel in m/m (dimensionless). • n is a dimensionless empirical constant called ...

Get price### Friction Factors and Drag Coefficients

Based on the specific type of pipe, a pipe manufacturer might provide a more detailed set of measurements for f. If a pipe is not circular, f from the above figure can still be used as a rough approximation for the friction factor. For a pipe with a cross-section other than circular, the effective pipe diameter D' is defined as D' = 4 A/P w (8)

Get price### Chapter 7 FLOW THROUGH PIPES

FLOW THROUGH PIPES 7-1 Friction Losses of Head in Pipes 7-2 Secondary Losses of Head in Pipes 7-3 Flow through Pipe Systems ... Concrete-lined Ductile Iron 0.03 . Faculty Of Engineering at Shobra 2nd Year Civil - 2016 Fluid Mechanics, CVE 214 Dr. Alaa El-Hazek 53

Get price### OPERATIONAL PROBLEMS IN PUMPING NON-SETTLING

Proceedings of the Twenty-Eighth International Pump Users Symposium September 24-27, 2012, Houston, Texas . OPERATIONAL PROBLEMS IN PUMPING NON-SETTLING SLURRIES RESOLVED . USING AN IMPROVED LAMINAR FLOW PIPE FITTING LOSS MODEL . Daniel W. Wood. Rotating Machinery Consultant . DuPont . Wilmington, Delaware, USA . Trey Walters, P.E. President

Get price### Modeling of Suspension Flow in Pipes and Rheometers

Modeling of Suspension Flow in Pipes and Rheometers Nicos S. Martys1, Chiara F. Ferraris1, and William L. George1 1National Institute of Standards and Technology Abstract Measurement and prediction of the flow of suspensions like fresh concrete represents a significant challenge for both the experimentalist and modeler.

Get price### THE RHEOLOGY OF FRESH CEMENT AND CONCRETE − A

In a shear flow imaginary parallel layers of liquid move in response to a shear stress to produce a velocity gradient, which is referred to as the shear rate, equivalent to the rate of increase of shear strain. Elongational or stretching flows are rarely found in cement systems but there may be some elongation at the entry or exit of a pipe.

Get price### Concrete Pumping - How to Pump Cement - Concrete Network

Line length: Concrete being pumped through a line experiences friction with the internal wall of the pipeline. The longer the line, the more friction encountered. For longer pumping distances, the use of smooth-walled steel pipe can lower the resistance. The length of hose used at the end of the pipeline adds to the overall line length as well.

Get price