Dredging Engineering, Trenching & Deepsea Mining

Machinery for the treatment of soil and/or bulk goods are constituting an interface between Mechanical Engineering and Civil Engineering. Within this framework one must think of dredging machinery, tunnel drilling machines and equipment for the treatment of bulk goods. This field comprises excavation, transport and sedimentation processes of soil, rock and bulk goods that are brought about by human intervention and controlled by means of the appropriate machinery. The purpose in this is to realize or maintain "constructions" and to mine, transfer or treat building materials or ores. Examples of the constructions mentioned above are: ports, channels, land reclamation, cores of dykes and (drilling) tunnels. Examples of the treatment of materials are: soil treatment, mixed heap systems and the separation of materials when mining minerals. Examples of transference are: the transshipment of bulk materials, conveyor belts in the mining industry and hydraulic transport of solids. An important development in this is the drilling of tunnels in "feeble" ground.

The designing of and working with the equipment mentioned above is primarily determined by physical processes, such as loosening up rock, soil or bulk materials, vertical and horizontal transport, positioning in the means of transport, treatment and positioning of the material in a desired geometry.

To design dredging equipment, one first has to understand the processes involved.

The fundamental research focusses on the cutting processes in sand, clay and rock, stationary and non-stationary flow of mixtures through pipelines, the sedimentation in hoppers, mixture forming in cutterheads, the behavior of cutter dredgers under offshore conditions, while more applied research has been carried out on many different subjects usually in cooperation with the dredging industry.

When designing machinery, a large number of restrictions play an important part. They all relate to local circumstances, such as the availability of facilities, the condition of the soil or bulk goods, the availability of resource-rich areas for the purpose of elevation, dumping sites for the removal of materials from digged-in constructions, wind and weather conditions, environmental requirements, available energy and a large number of other technical, administrative and economic restrictions. Furthermore, it is required to possess a profound insight into the availability of highly sophisticated mechanical constructions that often have to operate under heavy and dynamic load conditions due to the aggressive environment.

The education of MSc students has always been based on developing the problem solving capabilities of the students. In general the final MSc thesis has always been directed to solve complex state of the art problems mainly from the industry. Based on a problem analysis founded on the fundamental physical processes, conceptual solutions have to be generated. A multi-criteria analysis has to be carried out resulting in the most promising solution, which has to be ‘designed’. Since 1977 roughly 200 students graduated and 5 PhD thesis have successfully been defended.

The courses of this specialisation are:

Dredging Processes

The course focuses on 3 main dredging processes:
The cutting of sand, clay and rock;
The sedimentation process in hopper dredges;
The breaching process.
These are explained in detail.Exercises allow participants to apply the knowledge gained in practical situations.

Study goals:

Understand and reproduce the Mohr circle;
Understand and reproduce the theory of passive and active soil failure;
Understanding the soil mechanical parameters important for cutting processes;
Understanding and make calculations regarding the 2-D cutting theory in water-saturated sand;
Understanding and make calculations regarding the 2-D theory in clay;
Understanding and reproduce the settling of grains in water;
Understanding and reproduce the loading cycle of a hopper dredge;
Being able to determine the loading cycle of a hopper dredge, base on the modified Camp model by Miedema and Vlasblom;
Understanding and reproduce the basic cutting theory of rock cutting;
Understanding and reproduce the breaching process.

OE4626 / 4 ECTS / Digital Study Guide

Dredging Pumps and Slurry Transport

This course prepares one to design and optimize a pipeline - pump system for slurry transport. Factors including the length and slope as well as overall pipeline wear and energy efficiency are all considered in relation to the rate of solid material transport.
OE4625 / 4 ECTS / Digital Study Guide

Deep Sea Dredging Equipment Design

This course prepares one primarily to design dredging equipment for specialized applications - such as diamond mining or gas hydrate recovery - in deeper (in the offshore sense) water.
OE5671 / 4 ECTS / Digital Study Guide

For research on Dredging goto: Dredging Engineering