Breakwater design

Lecture notes on the design of rubble mound and caisson breakwaters.Hydraulic EngineeringCivil Engineering and Geoscience

Coastal Engineering. Volume I

Natural system, coastal dynamics, climatology, oceanography, morphology. Coastal formations, Coast and culture, The Netherlands.Hydraulic EngineeringCivil Engineering and Geoscience

Generation of irregular waves on model scales

Wind-wave flumes have been added to the laboratory facilities since a long time, in order to simulate natural wind lv-aves. Most wind-wave flui'nes have been equipped in addition with mechanical (regular) wave generators to avoid extreme small model scales. For some time past a programmed (irregular) wave generator has been installed in one of the existing wind flumes of the Delft Hydraulics Laboratory. After a historical review of the development of wave generating facilities a comparison has been made of the various kinds of wave generation. Moreover, some records of North Sea wave conditions have been added to the comparison

Berm breakwater structures: Dynamically stable structures and their natural response to wave attack

Wave interaction with dynamically stable structures is studied by means of a verified numerical model. The model can simulate wave motion on and in permeable structures. For dynamically stable structures, including gravel beaches, berm breakwaters and reef-type structures, a procedure is developed to simulate the natural response to wave attack. Also a verification with prototype measurements is performed.Berm Breakwater

Inter institutional workshop on breakwaters

(1) Functional requirements for Breakwaters - Prof. K.d' Angremond (2) Development of fishery harbors in India - Mr. K. Omprakash (3) Non-rubble Breakwaters and optimisation - Prof. K.d' Angremond (4) Wave energy caisson Breakwaters - Dr. S. Neelamani (5) Partially suspended porous wall Breakwaters - Dr. J.S. Mani (6) Case studies on stability of Breakwaters - Prof. V. Sundar (7) Introduction on Ennore coal port project - Mr. L.A. Mayboom (8) Design of Breakwaters for Ennore port - Mr. R. Haggie (9) Construction of Breakwaters for Ennore port - Mr. S. PearsonHydraulic EngineeringCivil Engineering and Geoscience

Mining activities in a coastal zone: Effects and remedial measures in the Netherlands

In July, 1959, the presence of gas in the subsoil of the Province of Groningen in the extreme NE part of the Netherlands was confirmed. Subsequently, it became clear that the mining of the gas would result in considerable subsidence and a disruption of the drainage system of an area adjacent to the North Sea, and situated already partly below sea level. To prevent damage on land, extensive remedial measures were designed and carried out. The cost of the remedial measures was compensated under a special agreement between the stakeholders and the mining company. In this way lengthy and costly court procedures could be avoided. In 1994, new gas reserves were found under the Wadden Sea, a part of the North Sea that is shielded by a long row of barrier islands along the Dutch, German and Danish coast. The Wadden Sea is a Wetland Area according to the Ramsar Wetland Convention and a protected nature conservation area under European legislation. It took about 10 years to get these reserves nevertheless into production due to political discussions and court proceedings filed by NGO’s and others. Based on scientific studies and the outcome of an advice from independent experts in 2004, all parties involved were willing to find a way out of the deadlock situation. Eventually, agreement was reached between the mining company, the national and local Government and the NGO’s. The aim of the agreement was to ensure that gas production could not lead to deterioration of the ecological qualities of the Wadden Sea. Also financial means were provided to support improvements to the quality of the area. By listening to each other, and focussing on a positive outcome for all parties involved, here again, further lengthy and costly court procedures could be avoided. In 2007 gas production from locations under the Wadden Sea has commenced.Hydraulic EngineeringCivil Engineering and Geoscience

Positioning of cubes on a breakwater slope

Recent research has shown that it is possible to use concrete cubes as a single armour layer on breakwaters. However, this is only possible in case a placing density of at least 70 % is achieved. In lab-tests it is no problem to place cubes with this density, however it is questionable if such a placing density can be achieved in prototype situations. A number of tests have been carried out in order to determine the requirements for dropping concrete blocks from a crane onto a breakwater slope. The conclusion is that at a waterdepth of approximately 10 times the block size this just can be achieved and that at smaller depth this placing density can be reached without too many difficulties. However, in all cases a good quality toe is vital for a high placing density. Blocks have to be placed at an angle of 45° with respect to the breakwater axis; blocks placed parallel to the breakwater axis will lead to large voids.Hydraulic EngineeringCivil Engineering and Geoscience

Introduction to coastal engineering

Lecture notes on genesis of the coastline, climatology, oceanography, coastal morphology, coastal formations, coastalzonde management, tidal inlets and estuaries, pollution and density problems, practical problems and common solutions.Hydraulic EngineeringCivil Engineering and Geoscience

Stresses in tetrapod armour units introduced by wave action

in this study an analysis concerning the pulsating and impact portion of the tensile stresses inside tetrapod armour units is presented. The data has been obtained from a series of small scale model tests performed at Delft Hydraulics. Stresses have been measured using a load cell technique developed and made available by Coastal Engineering Research Centre in association with Aalborg University. For the rested area of the breakwater the following parameters only appeared to have influence on the stress distribution inside a leg of a tetrapod: (1) significant wave height; (2) water depth in front of the breakwater. Other parameters investigated which appeared to have no or negligible influence on the stress distributions were: (1) the fictitious wave steepness; (2) the location of the tetrapod; (3) the orientation of the instrumented leg of the tetrapodRubble mound breakwaters failure mode