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A seismic vibrator driven by linear synchronous motors
The seismic vibrator is an advanced seismic method to obtain images of the subsurface in a non-destructive way. The vibrators that are generally used suffer from the distortion of the signal in the low-frequency band that contains an important part of the data. This new type of vibrator is driven by linear synchronous motors (LSM) and it can produce very repeatable signals in the low-frequency band. The ability to produce undistorted low-frequency signals makes this new source suitable for the analysis of surface waves to extract shear wave velocities down to considerable depths and to investigate the response of buildings to earthquakes. It also opens up possibilities for the automatic processing of the seismic data through full waveform fitting.
Global earth observation for integrated water resource assessment
Global water resources are under pressure due to increasing demand from industry, agriculture, energy, tourism and households. At the same time, climate change may shift the balance in many regions of the world. It is still difficult to assess the quality of water resources, and access to those resources, in many regions of the world which lack basic observation and monitoring systems. Deltares is coordinating eartH2Observe, an EU FP7 project that aims to use global water data from models and satellites at the local level in order to support decisions about the management of water resources. This involves combining the results of ten global hydrological and land surface models with large amounts of remote-sensing data. In addition, the results are being verified and refined in a number of case studies around the world (including Bangladesh, Colombia, Australia and Ethiopia) in which local water managers use the data in their region.
Sustainable Development Goals for water
In September 2015, heads of state from all around the world adopted the 2030 Agenda for Sustainable Development consisting of 17 Sustainable Development Goals (SDGs) and 169 targets. The 2030 Agenda includes a dedicated goal on water and sanitation (SDG 6) that sets out to ‘ensure availability and sustainable management of water and sanitation for all’. Indicators include changes in the efficiency of water use over time and the level of water stress, which relates water withdrawal (‘abstraction’) to available freshwater resources. Six Proof of Concept countries (Bangladesh, Peru, Jordan, Uganda, Senegal and the Netherlands) were invited to test the methodologies developed by UN organisations and to collect data for these indicators. As a result of the Proof of Concept process, Statistics Netherlands (CBS), Deltares and eLEAF conducted a demonstration project aiming to show how indicators can be compiled for the Netherlands, and what data can be acquired to support other countries in the process of evaluating indicators. The project received support from the Dutch Ministry of Infrastructure and the Environment and Ministry of Foreign Affairs.
Risk- and Opportunity-Based Asset Management for Critical Infrastructure (ROBAMCI)
The Risk- and Opportunity-Based Asset Management for Critical Infrastructure (ROBAMCI) programme (2015-2018) uses a risk-based and system-oriented approach to improve the management and maintenance of public infrastructures. The programme shows that an efficiency gain of more than 10% (€ 1-2 billion a year in the Netherlands) can be achieved by using riskbased and system-oriented asset management for decisions in life-cycle management. The ROBAMCI programme is a collaboration between government, private companies and research institutes which provides a wide-ranging and complete base of relevant knowledge and data.
Bayesian Estimator of Wave Attack in Reef Environments (BEWARE)
Deltares collaborated with the U.S. Geological Survey to generalise previous site-specific studies of flooding on coral atolls and to develop a new approach to estimating flood risk on low-lying tropical islands. Using the wave model XBeach (which is open source), we developed a large synthetic database of numerical simulations representing a large range of realistic reef geometries, and wave and sea-level conditions. We then entered the model results in the BEWARE (Bayesian Estimator of Wave Attack in Reef Environments) network, a probabilistic model which estimates a range and distribution of likely outputs for a given set of inputs. The resulting tool allows us to make real-time flood predictions based on predicted offshore wave or sea-level conditions, and the unique characteristics of a given island.
Using past performance for updates of dike reliability
Reliability updates for dikes involve including observations of past performance in estimates of a dike’s present reliability. In this project, reliability updates were made operational by developing the method, applying it to specific cases, building software and drafting manuals. As Dutch dikes have already typically endured significant load conditions, the reliability updating method is expected to have a major impact.
Collaboration between Port of Rotterdam and Deltares continues on Porto Central
Porto Central (PoC) is a new private industrial port complex located midway along the Brazilian coast in the south of the state of Espírito Santo. This port is being developed in a joint venture involving TPK Logística S.A (TPK, Brazil) and the Port of Rotterdam Authority (PoR, Netherlands). The project will allow PoR to continue with the establishment of its World Port Network, which also includes Sohar Port and Freezone in Oman. Deltares is contributing its expertise on sediment transport and wave modelling to these developments.
Viability study of a prototype windstorm for the Wadden Sea surges
This study aims at investigating whether and how a prototype for windstorms can be used to realistically simulate severe surges and associated currents in the Wadden Sea. This prototype is inspired to the wind associated with atmospheric cyclonic circulation in the North Sea. Prototype-like synthetic profiles of wind speed and direction prescribe the peak wind speed, the durations of rising speeds and of a subsequent plateau, and the compass sector swept by the wind direction while turning clockwise. The wind fields are uniform over the entire computational domains, and tidal effects are omitted to concentrate on wind-driven surges.
Simulation studies for storm winds, flow fields and wave climate in the Wadden Sea
The motivation for this study is to assess the possibility of using wind, current and water level fields as simply as possible for the determination of the Hydraulic Boundary Conditions (HBC) in the Wadden Sea. Since storms are intrinsically unsteady processes, the purpose of this study is to investigate physically-based methodologies to simplify the wind fields that generate severe surges and use then as realistic forcing on the water in the Wadden Sea. An additional purpose is to perform a sensitivity analysis to various model settings for the determination of the wave conditions in the eastern Wadden Sea.
Analyse macrostabiliteit dijken met de eindige elementen methode
Binnen het deelproject ‘Analyse macro-stabiliteit van dijken met EEM’ worden een veiligheidsfilosofie en stappenplan ontwikkeld voor het toetsen van de macrostabiliteit van primaire waterkeringen (al dan niet met eenvoudige constructies zoals damwanden) met behulp van Eindige Elementen Methode, met als doel te komen tot een richtlijn waarmee in de praktijk tot resultaten uit 2D plane strain stabiliteitsanalyses op basis van de Eindige Elementen Methode wordt gekomen die in een toetsing aan de wettelijk vereiste veiligheid worden geaccepteerd.