145 research outputs found
Xbloc armour unit development - hydraulic performance of Xbloc armour units, 2D model tests at WL Delft
No full textThe coastal team of Delta Marine Consultants [DMC] have taken the initiative to develop a new concrete armour unit for application on breakwaters and shore protections. Following the preliminary model tests conducted at DMC, 2-D hydraulic model tests have been carried out at Delft Hydraulics in October 2002. The experimental set-up and test procedure as well as the main results are briefly reported by Delft Hydraulics [report H4185, Jan 2003]. A comprehensive description of the 2-D hydraulic model tests, test results and further analysis on wave overtopping and hydraulic stability is presented in this report
Hillblock model tests, 2D model testing report
No full textThe Hillblock is a concrete element for the protection of dike slopes. Delta Marine Consultants (DMC) investigated the hydraulic properties of the Hillblock in 2D model tests. Wave run-up measurements have been performed on dike slopes with Hillblock revetment and on a smooth impermeable reference slope. The model tests have been carried out at the DMC wave laboratory in Utrecht. Three different dike slopes have been tested: 1:2, 1:3 and 1:4. Two different Hillblock placement patterns have been tested on a 1:4 slope: Standard placement (with relatively large permeability in cross direction) and modified placement (with relatively large permeability in up-slope direction). The wave run-up has been recorded on the reference slope (smooth slope) and on the Hillblock slope by a video camera; the wave run-up heights have been determined from the video records. The run-up heights (with 2% probability of exceedence) on the Hillblock slope are in average 27% smaller than on the reference slope. The reduction may vary from 15% to 35%
Dynamic matrix controller design and optimization based on a MIMO double-effect pilot plant model
No full textDynamic Matrix Control (DMC) has developed considerably over the last two decades, both within the research control community and in the industry. The reason for this success can be attributed to the fact that it is, perhaps, the most general way of posing the process control problem in the time domain. DMC formulation integrates optimal control, control of process with dead time, multivariable control and future references when available. Another advantage of DMC is that because of the finite control horizon used, constraints and in general non-linear processes which are frequently found in the industry, can be handled.Master of Science (Computer Control and Automation
Dimethyl carbonate synthesis from CO2 and methanol over CeO2: elucidating the surface intermediates and oxygen vacancy-assisted reaction mechanism
No full textSurface intermediate species and oxygen vacancy-assisted mechanism over CeO2 catalyst in the direct dimethyl carbonate (DMC) synthesis from carbon dioxide and methanol are suggested by means of transient spectroscopic methodologies in conjunction with multivariate spectral analysis. How the two reactants, i.e. CO2 and methanol, interact with the CeO2 surface and how they form decisive surface intermediates leading to DMC are unraveled by DFT-based molecular dynamics simulation by precise statistical sampling of various configurations of surface states and intermediates. The atomistic simulations and uncovered stability of different intermediate states perfectly explain the unique DMC formation profile experimentally observed upon transient operations, strongly supporting the proposed oxygen vacancy-assisted reaction mechanism.ChemE/Catalysis Engineerin
Correlating permeability with drainage layer thickness overlying dredged marine clay in consolidation
No full textDredged marine clay (DMC) known to have low permeability as fine-grained soils. The reuse of
DMC as construction material could be a sustainable approach. Therefore, this research aims to
correlating the permeability with granular drainage layer thickness by overlaying DMC. Except
sand, recycled granular materials (recycled pavement materials and palm oil clinker) used as
drainage layer. Laboratory testing was performed to determine the engineering properties of all
materials and large oedometer test for the consolidation. DMC are categorised as CH soils, while
sand and palm oil clinker can be considered as well-graded except for recycled pavement
materials as poor-graded gravel. The k-value of Lsc (control) placed at the bottom compared the
others specimen with drainage layer due to its low permeability properties with the kave of 7.31 x
10-9 m/s. The thickness of granular materials at 100% had positioned on top of 50%. In conclusion,
by increasing the thickness of drainage layer, the dissipation of water also increases and speed
up the consolidation of DMC. Therefore, it can conclude that recycled granular by-products can
be reuse as backfill materials for land reclaimed
Rapport Caissonbouw: De geschiedenis van de caissonbouw bij de Hollandsche Beton Groep nv van 1902 tot en met 1977
No full text'Caissonbouw' is het verhaal van een methode van uitvoeren die uitgroeide tot een industriële bouwwijze. Het geeft een beeld van menselijk vernuft en technische doelmatigheiden en schetst de reis van een constructiemethode door vier werelddelen over een spanne tijds van ongeveer 75 jaar
Review of proposed section of Accropode and Xbloc stability for CRESS update
No full textOverview of computational rules for Accropede and Xbloc in CressCres
Review of a harbour layout and tsunami research in Golfo de Arauco
No full textThe shipping company CSAV wants a new harbour to be built in Golfo de Arauco in Chile. The bay is situated directly south of the city Concepcion. DMC designed a layout for this harbour. Along the coast of Chile tsunamis can occur. The design made by DMC does not reckon with this phenomenon. In this report at first a review of the harbour layout made by DMC is done. After that research is done on the tsunami subject with the help of a simulation program. DMC proposed to use MII<E21 because it was available as an entry level version at the time of the research. The review of the harbour leads to an increase of the number of container berthing places based on the used starting points. The container storage area is increased as well. The tsunami is described with the help of empirical relations. An aftershock generates a tsunami area after which it travels towards the coast of Chile and towards the ocean where it even can reach Japan. The aftershock area is schematised to a one-dimensional model. With the help of this model is made clear that the height of the tsunami will be larger when the vertical amplitude of the aftershock area is larger. Golfo de Arauco is implemented into the simulation model as well. It is made clear that the tsunami will bend along the island Santa Maria that is situated in the bay area. The site of the harbour is the first area on the coast hit by the tsunami. The height of the stunami is not fully developed however, because of the trench that is situated perpendicular to the coast north of the site. To minimise the damage of the tsunami the orientation of the containers on the terminal must be changed. The traffic lanes must have an orientation in the propagation direction of the tsunami. The tank farm must be placed under the ground.Hydraulic EngineeringCivil Engineering and Geoscience
Inkjet printing P(VDF-TrFE-CTFE) actuators for large bending strains
No full textAdditive manufacturing of sensors and actuators together with structural materials and electronics will make it possible to fabricate innovative system designs that are overly laborious to realise with conventional methods. While printing of the structural materials and electronics are advancing fast, the additive manufacturing methods for actuators and sensors are in an earlier stage of development. This research will develop a manufacturing process for entirely inkjet printed electroactive polymer (EAP) actuators basing on the P(VDF-TrFE-CTFE) relaxor ferroelectric polymer and Ag electrodes. The process consists of (1) printing an Ag layer on a polyethylene terephthalate (PET) substrate for the bottom electrode; (2) formulating, printing and annealing a P(VDF-TrFE-CTFE) ink for the EAP layer; and (3) printing and sintering an Ag layer on the plasma-treated EAP surface to form the top electrode. Two actuator variations, addressed as DMC and KM512, are manufactured and characterised by their: (a) response to quasi-static excitation (1 Hz sine wave); (b) hysteresis behaviour; (c) actuation amplitude variation with the input voltage; and (d) frequency response. The 18 mm long actuators showed 91.4 µm (DMC, 200 V p p ) and 224 µm (KM512, 275 V p p ) deflections in response to 1 Hz sinusoidal excitation, and 1.10 mm (DMC, 113 Hz, 200 V p p ) and 1.72 mm (KM512, 114 Hz, 200 V p p ) deflections in resonant operation. It is 55% more quasi-static strain and 470% more resonant strain than in earlier fully inkjet-printed polyvinylidene fluoride (PVDF) -based actuators, and comparable to similar partially inkjet-printed actuators. This is the first time that inkjet printing of all three layers of a relaxor ferroelectric actuator have been achieved.Micro and Nano Engineerin
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