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

Experimental study on rock cutting with cutter teeth of cutter suction dredger
Gongxun Liu1, Xin Liang1, Guojun Hong1, Xiuhan Chen2, Liquan Xie3, Peng Jin1, Kang Xie1
1: National Engineer Research Center of Dredging Technology and Equipment, Shanghai, China
2: Delft University of Technology, Delft, Netherlands
3: Tongji University, Shanghai, ChinaABSTRACT

rotates at high speed in the construction process, directly interacts
violently with underwater cutting medium and bears huge cutting load.
Compared with sediment dredging, rock excavation requires higher
performance of cutter. The determination of cutting force and theresearch of excavation effect in the process of cutter teeth cutting rockhave important guiding significance for the design of cutter head anddredging construction.
In this paper, the concrete sample is creatively prepared to replace thenatural rock sample. The linear cutting rock test of the cutter teeth iscarried out by using the large-scale model test platform. The cutting
resistance of the cutter teeth and the groove shape of the sample under
different cutting angles and cutting depths are compared and analyzed..

Cutter suction dredger is one of the ship types widely used in dredging
engineering, especially for rock dredging, this ship type has more
obvious advantages. Compared with dredging of sediment, rockexcavation requires higher performance of cutterhead. Therefore, thedetermination of cutting force and the research of excavation effect in
the process of cutting rock with cutter teeth have important guiding
significance for the design of cutterhead and dredging construction. In
view of the heterogeneity of natural rock material, complex internalmechanical properties and poor regularity and repeatability of tests,
concrete samples were innovatively prepared to replace natural rocksamples. A large scale model test platform was used to test the linear
cutting of rock by cutter teeth. The cutting resistance of cutter teeth
and the groove shape of the rock sample under different cutting angles
and cutting depths were compared and analyzed. The test results showthat in the process of rock cutting, cutting resistance of cutter teeth
varied linearly with cutting depth, but the regularity was not obvious
when cutting depth was small. The dimensionless cutting specificenergy (SEQ) decreased with the increase of cutting depth, and it
decreased rapidly when the cutting depth was small; when the cutting
depth reached a certain value, SEQ basically did not change. The
cutting width increased with the increase of cutting depth while they
were linearly correlated, and the fitting curves under different cutting
angles were basically the same.

2. MECHANICS OF ROCK CUTTING
In order to facilitate the analysis of cutting force, the cutting process isoften simplified to linear. Over the years various cutting models havebeen developed to substantiate the physics that come paired with therock cutting process (Evans, 1984; Nishimatsu, 1972). But in the past,
the researches focus of rock cutting test were mostly in small scale,and the cutting depth was mostly within 1cm (Rostamsowlat, 2018;
Yasar & Yilmaz, 2018).

KEY WORDS: Cutter suction dredger; Rock dredging; Cutter tooth;Cutting Angle; Cutting depth; Cutting resistance; Cutting specificenergy ; Debris
1. INTRODUCTION
Cutter suction dredger is a kind of engineering ship widely used inchannel dredging, harbor construction, water area environmental
protection, reclamation of land from the sea and artificial islandbuilding. Cutter is the core component of cutter suction dredger. ItFig. 1 Schematic representation of top view and side view of thecutting tool44