· · · Institutional Repository

Research into hydraulic loads by a bow thruster. The hydraulic loads on the slope at an open quay construction on piles is investigated. The propeller (bow thruster) jet induces hydraulic loads on the bed, which could result in scour holes and damage to the quay construction. Performed scale model tests provide details about the hydraulic loads in this specific situation with an inclining slope and piles. Measurements are compared to the current engineering guidelines, to include in the design of open quay constructions on piles.

In this report will be explained how breakwaters can be made with the use of Elastocoast, a sort of glue. This makes it possible to fix the individual rocks, and allows repetitive tests possible with exactly the same layer properties. We made six samples of breakwater rock layers, made with Elastocoast and stones, which can be placed and tested in the wave flume. For doing tests it is important to know the properties of the breakwater, such as the grain size distribution, the porosity and the permeability. The permeability and porosity tests were performed on smaller parts than the slabs to be used in the model breakwater. After making the little samples we made the large ones, on the same way, for use in the wave flume. For the testing of the permeability we used a construction in which we could let water flow through the samples. This report shows the results of our tests, so these results can be used for further purposes, when other people use these breakwater samples.

Although the effect of wave attenuation by mangrove has been widely observed and studied, the problem pertaining to how to accurately describe the geometrical properties is still remaining unresolved. Also, the material properties of mangrove root have not been comprehensively studied before. This is study is dedicated for the survey on geometric and material properties of mangrove in Singapore for future modeling work. In this study, two types of mangrove are surveyed, as Sonneratia alba and Rhizophora, for the two survey types of mangroves are mostly abundant in Singapore and Johor River region. Photogrammetry technique has been extensively practiced for capturing the geometrical properties of the mangrove root. Lab testing has been carried out to obtain the material properties of mangrove root. The geometrical properties studied are mainly root density, root distribution and root height. The material properties studied are the mass density, moisture content and modulus of elasticity of the mangrove roots.