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

Mechanism and numerical analysis of rock cutting by cutterhead
Xin Liang1, Gongxun Liu1, Peng Jin1*, Guojun Hong1, Liquan Xie2
1: Key Laboratory, National Engineer Research Center of Dredging Technology and Equipment
Shanghai, China
2: Department of Civil Engineering, Tongji University
Shanghai, China

project, the cutting tool (cutterhead) installed at the front end of thebridge is placed in the working area by the cutter frame, and theunderwater soil is stirred and loosened by the rotary cutting of thecutterhead. The soil loosened by the cutter is mixed with water to form
mud. Under the action of atmospheric pressure, the mud is pressed into
the mud suction pipe at the back of the cutter, Then, the mud water
mixture is pumped out by the mud pump and transported to thereclamation area (or the designated sludge unloading area) to complete
the dredging operation.
The research of rock cutter has always been one of the difficult
problems in the field of dredging engineering. In order to study rockdredging engineering, many scholars at home and abroad have carriedout experimental research on the interaction between cutter teeth androck (Kang H et al, 2016; Rostamsowlat I,2018; Yasar S, and Yilmaz
AO, 2018). However, due to the factors such as site and power, most of
the current cutting tests have limitations, such as small scale, or only
single cutter cutting research. Scholars have carried out a series ofstudies using finite element method (Kou SQ et al, 1999; He J, andVlasblom W, 1998). However, the finite element method based oncontinuum mechanics has some problems in simulating thediscontinuity caused by rock cutting process (Jonak J, and Podgorski J,2001). Because the discrete element method (Cundall PA, 1970 &Cundall PA, Strack ODL, 1980) can be used to simulate large
deformation and crushing changes, it is widely used in the simulation of
cutter cutting process. Scholars have carried out a series of studies onrock crushing process (Dai Y et al, 2016), cutting process (Jerzy R et al,2011), cutting depth (Okan S and Nuri AA, 2011). However, the above
studies mostly focus on cutting process and rock breaking mechanism,based on one kind of specific cutter tooth. There are relatively few
studies on the comparison of cutting resistance force of different typesof cutter teeth.
Compared with sediment dredging, rock excavation puts forward
higher requirements for the performance of the cutter, and the cutter
tooth, as the core component of the cutter, its strength, rock breaking
performance, energy consumption, etc. are particularly critical. TheABSTRACT
Cutter suction dredger is one of the most widely used dredger types in
Waterway Dredging Engineering, with the advantages of strong
adaptability to complex environment and high efficiency. Based on
DEM (discrete element method), this paper studies the cutting
efficiency of rock cutter teeth and the cutterhead systematically. The
cutting experiments of single cutter are simulated, and the change
characteristics of cutting force and cutting power under different
cutting parameters and the failure mode of rock specimen are compared.
The results show that the average cutting force is approximately
proportional to the peak cutting force, which is about 1.2~1.6 times of
the average cutting force during the cutting process. The pickcutterhead has the advantage of stable power, but the cutting output isrelatively low.

KEY WORDS: Cutter suction dredger; sharp tooth; pick; DEM;
cutting resistance force; cutting output
1. INTRODUCTION
In recent years, with the continuous development of China's economy,
water transportation, as one of the main modes of transportation, hasplayed an extremely important role. In order to ensure the efficiencyand safety of water transportation, channel dredging is necessary. With
the increase of transportation demand and the development of
shipbuilding technology, the requirements for channel water depth arealso increasing. Cutter suction dredger is widely used in dredging
engineering because of its wide application range, continuousconstruction, excavation, transportation and reclamation.
Cutter suction dredger is one of the most widely used dredger types in
Waterway Dredging Engineering, with the advantages of strong
adaptability to complex environment and high efficiency. The cutter isthe core equipment of cutter suction dredger, and the cutter teeth on thecutter are the part directly contacting with soil or rock. In the dredging

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