Exploration and Research on a New Jetting Draghead
Type:
Presented during:
WODCON XIX: "Dredging makes the World a better place" - 2010, Beijing, China
Authors:
Jiang Shuai, Shu Wei
Abstract: To improve the construction efficiency of the trailing suction hopper dredger (TSHD), the key problem is to raise the dredged material density of the draghead, Therefore the high-pressure jet has been more and more frequently used in dragheads though it has only played a supporting role. The paper exploratively presents a new draghead in which the high pressure jet is playing a major role and the machinery excavation is auxiliary. According to the water sword’s principle and in order to achieve the purpose of maximizing the effect of breaking soil, the vertical and horizontal jetting can cut enough in soil. Through the suction of the dredge pump and the controlling of the sailing speed, the loose soil will be absorbed as far as possible, then the excavation density at the draghead will be enhanced. Through a series of model tests, the excavation density at the new draghead was enhanced by more than 10% compared to the ordinary draghead. It was proved that the experiment achievement is reliable after testing on site, and the results provide the basis for deep research of the water sword draghead.
Keywords: construction efficiency, excavation density, cut, breaking soil, model test