14 research outputs found
De verbranding van gechloreerde koolwaterstoffen met terugwinning van zoutzuur
Document(en) uit de collectie Chemische Procestechnologie.DelftChemTechApplied Science
De droom van elke waterbehandelaar: QSAR's?
Het is ondoenlijk om voor elk nieuw stofje in bronnen voor drinkwater testen uit te voeren om na te gaan hoe dit stofje het beste verwijderd zou kunnen worden. Mogelijk bieden nieuwe rekenkundige methoden, waarmee staCsCsch verbanden tussen bijvoorbeeld eigenschappen en gedrag van een stof worden berekend (QSAR’s), hier uitkomst. QSAR’s staan nog in de kinderschoenen; er is nog veel validaCe nodig en dat vereist weer heel veel goed gedocumenteerde data. KWR verkent de mogelijkheden om al deze data in een internaConale database te gaan verzamelen.Water ManagementCivil Engineering and Geoscience
Experimental study of membrane fatigue response for asphalt multisurfacing systems on orthotropic steel deck bridges
In order to adequately characterize the fatigue response of the various membranes with surrounding multilayer surfacing layers on orthotropic steel decks and collect the necessary parameters for FE modeling, the details of the cyclic Membrane Adhesion Tester (MAT) are introduced. The fatigue damage in membrane interface is related to the amount of dissipated work computed by using the measurement of actuator load and piston deformation during the loading cycle. The dissipated work, which is equivalent to the lost part of the total potential energy of the membrane, has been utilized to explain the incremental damage during the testing. Furthermore, using the experimental data obtained from MAT, ranking of the bonding characteristics of various membrane products is demonstrated as well as the role of other influencing factors, such as the types of substrate and test temperatures.Structural EngineeringCivil Engineering and Geoscience
Real-time, adaptive measurement of corneal shapes
Conventional tools for measuring the shape of the cornea perform poorly when applied to abnormal eyes. The image processing regularly fails, and the shape reconstruction often produces inaccurate results. This article describes a single measurement instrument that could integrate real-time solutions to both problem
Digital technology impacts on the Arnhem transfer hall structural design
The new Transfer Hall in Arnhem is one of the key projects to prepare the Dutch railways for the increased future demands for capacity. UNStudio developed a master plan in 1996 for the station area of which the completion of the Transfer Hall in 2015 will be a final milestone. The Transfer Hall is a merging point of passengers, commercial and social interchanges, containing a multi-use development integrating program and flows of people and vehicles. The design includes a complex geometrical, double-curved shell roof where many functions are combined as well as many other geometrically challenging structural elements. This paper forms the fourth and final paper of a series [1][2][3] and focuses on the developments in digital technology during the project’s design and construction phase and how these developments could impact the structural design of a special project like this.Structural EngineeringCivil Engineering and Geoscience
Analysis of five-point bending test for multilayer surfacing system on orthotropic steel bridge
The French five-point bending test (5PBT) provides a laboratory scale test that allows studying the fatigue resistance of surfacing systems on orthotropic steel deck bridges (OSDB). The surfacing structure for OSDB in the Netherlands consists mostly of multilayer system: top porous asphalt layer, guss asphalt layer, steel deck and two membrane layers. In this paper, an analytical solution for 5PBT setup is presented first. In order to better understand the influence of geometrical, mechanical and structural parameters on the performance of the typical multilayer surfacing system of OSDB in the Netherlands, the 5PBT specimens with five structural layers have been investigated. The parametric study is performed at the numerical platform CAPA-3D that was developed at the Section of Structural Mechanics of TU Delft. The thicknesses of the top porous asphalt layer, middle guss asphalt layer and the steel plate are varied. The influences of the mechanical properties of both top and bottom membrane layers are studied. The sensitivities of those influence factors are evaluated by the examination of the maximum tensile stress at the top surface of the porous asphalt layers and the strain distributions through the entire thickness of the specimen at two cross sections.Structural EngineeringCivil Engineering and Geoscience
Experimental investigation of multilayer surfacing system on orthotropic steel bridge with the five-point bending test
Due to lightweight and flexibility, orthotropic steel deck bridges become popular the last decades but several problems were reported in relation to asphalt surfacing materials such as rutting, cracking, loss of bond between the surfacing system and steel deck. In the Netherlands a surfacing structure for orthotropic steel bridge decks mostly consists of five structural layers: top porous asphalt layer, guss asphalt layer, steel deck and two membrane layers. The five-point bending fatigue test is the standard device in France for asphalt concrete used on steel orthotropic deck bridges to perform the best asphalt mixture having a strong resistance to cracking. For the needs of this paper the 5 PBT was employed in order to evaluate the performance of the whole multilayer structure on steel deck and also to evaluate the mechanical properties of both top and bottom membrane and the influence they have on the structure. For the completion of the experimental investigation two types of specimen have been tested using the 5PBT set up. Displacement sensors have been used in order to detect the initiation of cracks where they are most likely to appear. Strain gauges have been used in order to monitor significant changes in strain on the Guss asphalt layer during the fatigue tests. Shear displacements between the asphalt layers are monitored and presented. It shows that the stiffness and the bonding characteristics of the intermediate membrane sheet as well as the wearing course behaviour seem to have great influence on the mechanical response of multilayer bridge surfacing system.Structural EngineeringCivil Engineering and Geoscience
Development of test method for assessing the bonding characteristics of membrane layers in wearing course laid on orthotropic steel bridge decks
In order to adequately characterize the adhesive bonding strength of the various membranes with surrounding materials on orthotropic steel decks and collect the necessary parameters for FE modeling, details of the Membrane Adhesion Test (MAT) are introduced. Analytical constitutive relations of the MAT device have been derived using the same methodology as Williams (1997). Furthermore, using the experimental data obtained from MAT, ranking of the bonding characteristics of various membrane products is demonstrated as well as the role of other influencing factors, such as the types of substrate and test temperatures.Structural EngineeringCivil Engineering and Geoscience
Regenwater als bron voor drinkwater in Nederland: een haalbare kaart?
Het idee om van regenwater drinkwater te maken wordt door steeds meer mensen omarmd. Is regenwater schoon, hoeveel neerslag valt er eigenlijk, en wat zijn de gevolgen, voor zowel drinkwaterbedrijven als huishoudens van het gebruik van regenwater om er drinkwater van te maken? Uit literatuuronderzoek blijkt dat er via daken minder neerslag kan worden opgevangen dan veel mensen denken, dat er toch wel verontreinigingen in kunnen voorkomen en dat het heel lastig wordt om de veiligheid te garanderen als hier drinkwater uit gemaakt wordt.Sanitary Engineerin
Regenwater als bron voor drinkwater in Nederland: Weegt milieuwinst op tegen de kosten?
Veel consumenten hebben het idee dat ze hun milieu-impact kunnen verkleinen door zelf uit regenwater drinkwater te maken. We hebben een levenscyclusanalyse en een kostenberekening gemaakt voor decentrale zuivering van regenwater op het niveau van een stadswijk en een individuele woning in het buitengebied. Op wijkniveau zijn de kosten acceptabel, maar voor een individuele woning zijn ze erg hoog. De meerkosten staan niet in verhouding tot de te behalen milieuwinst. Belangrijke praktisch problemen zijn dat er in dichtbebouwde stadswijken te weinig regen valt voor alle inwoners en dat er te weinig ruimte is om een dergelijke zuivering te plaatsen.Sanitary Engineerin