Print Email Facebook Twitter Laboratory experiments on the stability of concrete cubes Title Laboratory experiments on the stability of concrete cubes: a comparison of testing methodologies Author De Leau, J. Contributor Hofland, B. (mentor) Faculty Civil Engineering and Geosciences Department Hydraulic Engineering Date 2017-02-15 Abstract An important step in the design process of breakwaters is the laboratorial tests which show the performance of the breakwater. One of the important aspects in the performance is the stability of the armour layer. A common methodology for breakwater testing is a method in which the design wave conditions are simulated in four steps of 1000 or more waves. These steps start at 60% of the design conditions and every step the severity is increased. This test methodology is already applied for many years, but never has it been verified. Also in this methodology damage the evolution of a storm is not taken into account. In this MSc thesis research laboratory tests are conducted with a rubble mound breakwater structure with an armour layer of randomly placed cubes. A storm that was measured at the coast of Spain has been chosen to use and test on the breakwater structure. With a theoretical model a theoretical storm was calculated which based on literature should induce the same damage evolution as the measured storm, this theoretical storm is also tested on the breakwater structure. And the explained methodology is conducted on the same breakwater structure. The target of the tests was to judge the performance of the methodology, to indicate if the theoretical model produces correct theoretical storms and if based on the theoretical storm and the characteristics of a storm at which damage happens, recommendations can be given to improve/replace the methodology. The storms showed that mainly damage happened around the peak of the storm and in the build-up, but the tail of the storm (when the wave height is only decreasing) is of no importance for the damage development. An interesting aspect is that the build-up of a storm seems to be very important for the stability. The testing methodology performed really well, but the duration of the 100% step is an important consideration since a longer duration will cause more damage. Also was found that the safety factors that are used in the design of cubic armoured breakwaters are quite conservative. Finally the damage evolution due to the theoretical storm was not comparable compared to the damage evolution due to the simulated real storm, both in final damage as in the incremental damage. This led to the conclusion that the theoretical model describe by the literature was not a correct model to produce a theoretical storm for this chosen storm. As a general conclusion it can be said that the methodology that is already used for many years is performing well, but improvement is possible by considering durations of storms which at the moment is not done in the design process. Subject BreakwaterCubesStabilityflumelaboratory testsDamage developmentTheoretical modelsphysical experimentsDamageTesting methodologies To reference this document use: http://resolver.tudelft.nl/uuid:39da4d6b-e60e-4e0e-8a37-4fda0456dd3a Part of collection Student theses Document type master thesis Rights (c) 2017 Leau, J. de Files PDF MSc.Thesis.JordideLeau.Fi ... 1.2017.pdf 16.57 MB Close viewer /islandora/object/uuid:39da4d6b-e60e-4e0e-8a37-4fda0456dd3a/datastream/OBJ/view