Proceedings of the Thirty-second (2022) International Ocean and Polar Engineering Conference
Shanghai, China, June 5–10, 2022
Copyright © 2022 by the International Society of Offshore and Polar Engineers (ISOPE)
ISBN 978-1-880653-81-4; ISSN 1098-6189

www.isope.org

Research on Durand Formula Optimization and Field Application Based on Coarse Sand Pipeline
Transportation of Cutter-suction dredger
Chaozhe Yuan, Feixin Wang, Runli Tao**
Runli Tao

National Engineering Research Center of Dredging Technology and Equipment
Shanghai, China

Airport and Hong Kong Airport is mainly medium and coarse sand.
According to the situation of on-site construction, the pipelinetransportation resistance is greater. However, the Durand formula in thedredging specification is mainly obtained through theoretical analysis
and experimental data with small diameters, and cannot very accurately
represent the characteristics of pipeline transportation under theconditions of large diameters, large flows and high concentrations.
Therefore, it is not suitable for DN850-Q235 pipeline transportation ofcoarse sand, which brings difficulties to the friction size, row spacing
and output of coarse sand in pre-side pipeline transportation.

ABSTRACT
In order to solve the problem of large error between the coase sandpipeline transportation resistance calculated by Durand Formula and themeasured value, a field test was carried out in a certain project. Based on
the measured data, combined with the mathematical statistical analysis
method, the optimization of Durand formula has been realized. The
conclusions are given: the optimized formula can well characterize thepipeline transportation characteristics of the coarse sand, achieve highprecision & real-time prediction on the construction site, and thecalculation method of the critical flow velocity with minimum friction isgiven.

At present, major foreign dredging companies and scientific research
institutes have carried out a lot of research and field tests on thetransportation characteristics of large-diameter transportation pipelines,
accumulated rich experience, and developed and established relevant
calculation programs and formulas. And these results have not yet been
published publicly. However, China's dredging industry is still in thestage of numerical simulation and indoor small-diameter model test in
pipeline transportation research (Zhao, 2002, Deng, 2005, Sun, 2004),
and the field test and research work on large-diameter pipelines islacking (Zhao, 2018, Qu, 2021, Gong, 2021).

KEY WORDS: Dredging and reclamation project; Durand formula;transportation resistance; coarse sand; cutter-suction dredger; criticalflow velocity.

INTRODUCTION
In the land reclamation engineering, CSD and TSHD are mainly used to
the filling construction. And the pipeline transmission is an importantlink, and the loss of pipeline pressure is an important research content ofpipeline transportation characteristics. The current methods used forpipeline transportation resistance prediction is mainly based on threedifferent theories (Fei, 1994, Fei, 1986): diffusion theory, gravity theory
and energy theory. The representative empirical formulas based on theabove methods are Durand formula, Wasp formula, Wilson formula, Fei
Xiangjun formula, Wang Shaozhou formula, Chen Wenguang model,etc., and all have certain limitations and scope of application (Li, 2014,Durand, 1952, Wasp, 1977, Wilson, 2004, Wei, 2015). Among them, theclassic Durand formula has been tested by years of construction
experience (Ministry of Transport of the People's Republic of China,2012), and it can basically predict the transportation resistance ofcommon materials such as silt, silt and fine sand in large-diameter
pipelines (such as DN750 and DN850). At the same time, some scholars
have carried out a series of studies on the influence of different particle
shapes on the transportation resistance of straight pipelines and verticalpipelines (Chung, 1998, Chen, 2020).

Therefore, based on Xiamen Airport's reclamation project, this paper
conducts a field test and research on pipeline friction at the construction
site, and explores the friction calculation method and transportation
characteristics of coarse sand in DN850-Q235 pipeline transportation,
provides an important technical support for China's pipelinetransportation research.

Overview of the Field Test Study
Based on the mud discharge pipe of the cutter-suction dredger underconstruction in the Xiamen Airport Land Construction Project, this paper
carries out the test of the transportation characteristics of the muddischarge pipe under the normal construction state of the site. The test
pipe is a traditional steel pipe with an inner diameter of 850mm and amaterial of Q235. The cutter-suction dredger has a row spacing of 2498m,
a floating pipe of 602m, an immersed pipe of 1036m and a land pipe of860m. A typical test pipe section (Fig.1) for field testing is a 178m longpipeline in a land pipe, which consists of 13 steel pipes, 5 rubber pipes

In recent years, the filling medium in the expansion projects of Xiamen

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