In this research, the effect of curing with different types of current, current densities/voltage intensity on mortar is studied. The main objective is to explore the outcomes of electric curing on the setting time of CEM-I mortar. For achieving the main objective, an electrical curing setup is designed to accommodate curing with direct current, alternating current and pulsed direct current and the conventional vicat apparatus and its test procedure are modified in order to carry out the testing while a sample is being cured with current. Additionally, the effect of passing current on material properties such as compressive strength and resistivity is also studied. The temperature development during the curing process has also been monitored in the research. The electric charge and power calculation are done, for possible current/voltage regimes. The experiments revealed that the setting time can be altered by electrical curing of CEM-I mortar. The influence of electric curing for the chosen curing period is not significant as revealed from the compressive strength testing while the development of resistivity and temperature reveals that there is a correlation between these two properties. The effect of electric power applied to a sample is reflected in the results of the setting times. In the last chapter the findings of the study are summarised and recommendations, keeping in mind the possibility of expanding research in this field of study, have been made.

As facilities in the Dutch North Sea are approaching the end of their production life, the focus shifts from the developing to the decommissioning of facilities. The legislation on offshore pipeline decommissioning in the Dutch North Sea is currently unclear. The Minister can decide whether pipelines are to be removed or are allowed in situ. In situ decommissioning is considered unwanted by major external stakeholders. Besides, the pipeline owner holds an extensive liability for the pipeline after decommissioning. Full removal options, on the other hand, are accompanied with large environmental, technical and financial impact. This graduation thesis Accelerated pipeline degradation aims to investigate how accelerated degradation of steel can contribute to offshore pipeline decommissioning. By accelerated degradation it is aspired to limit the environmental impact and seabed disturbance. Furthermore, the costs and technical impact can be reduced. After evaluating the current decommissioning methods, a series of alternative options is assessed. The assessment has resulted in a further investigation of galvanic corrosion for steel degradation. With this investigation, it is aspired to evaluate the mechanism of galvanic corrosion to accelerate the corrosion of the steel pipeline. By doing so, the liability period at the sea bottom would decrease dramatically with respect to in situ decommissioning. The materials that could be applicable for galvanic coupling were considered. Due to its high standard potential and low costs, the use of graphite (carbon) is determined to be most suitable. Subsequently, several small-scale tests on low carbon steel. In a laboratory setting the galvanic corrosion of steel was investigated by coupling steel samples to carbon electrodes. Coupling with platinum electrodes is also tested to provide reference scenarios. The results of the tests show an increase of corrosion current with addition of a galvanic couple. However, with increasing cathodic surface the steel dissolution is limited by corrosion kinetics and diffusion limitations. A preliminary schematisation for implementation is designed. Accordingly, the main challenges are identified. The test results and identified challenges are the motivation for a field test. This field test is to be designed to investigate the potential feasibility issues that arise in the practical situation. Furthermore, the operational challenges can be addressed on the test site.