Searched for: author:"Walters, C.L."
(1 - 20 of 40)

Pages

document
Hussein, A. (author), Krom, A.H.M. (author), Dey, P. (author), Sunnardianto, G.K. (author), Moultos, O.A. (author), Walters, C.L. (author)
article 2021
document
Sunnardianto, G.K. (author), Bokas, G. (author), Hussein, A. (author), Walters, C.L. (author), Moultos, O.A. (author), Dey, P. (author)
A combined density functional theory and molecular dynamics approach is employed to study modifications of graphene at atomistic level for better H2 storage. The study reveals H2 desorption from hydrogenated defective graphene structure, V222, to be exothermic. H2 adsorption and desorption processes are found to be more reversible for V222 as...
article 2021
document
Bertolo, V.M. (author), Jiang, Q. (author), Walters, C.L. (author), Pupovich, V.A. (author)
One of the main challenges in applying thick-section high-strength steels (HSS) at arctic condition in offshore and maritime industry is to maintain a sufficient level of toughness to prevent brittle failure. An aspect that requires special attention is the through-thickness microstructural variation which may result in different local...
conference paper 2020
document
Walters, C.L. (author), Coppejans, O.J. (author), Hoogeland, M.G. (author)
In a prior project, TNO has presented a low-cost way of finding frac-ture toughness of base materials for cleavage fracture. That method features a small-scale CTOD specimen, combined with simplified sensors, less fatigue pre-cracking, faster testing, and no need for a temperature chamber. This meth-od has been extended to welds by considering...
conference paper 2019
document
Jiang, Q. (author), Bertolo, V.M. (author), Popovich, V.A. (author), Walters, C.L. (author)
Offshore activity in low-temperature areas requires the use of analysis methods that are capable of reliably predicting cleavage (brittle) fracture of ferritic steels in order to guarantee the structural integrity during service. Cleavage fracture is controlled by physical events at different size scales and is influenced by the multiple...
conference paper 2019
document
Coppejans, O.J. (author), Walters, C.L. (author)
Measurement of the fracture toughness of steel is important for the assurance of the safety of ships and offshore structures, especially when these structures are made of thick sections and/ or applied in cold environments. One key factor that will affect the determination of the fracture toughness is a pop-in, which is a short event in which...
conference paper 2019
document
Park, S.J. (author), Lee, K. (author), Choung, J. (author), Walters, C.L. (author)
This study deals with ductile fracture prediction of a marine steel using new damage functions. The stress triaxiality and Lode angle are known to be governing parameters on the ductile fracture. Recent research has reported that loading path is also one of the important parameters. A three-dimensional fracture strain surface for EH36 steel was...
article 2018
document
Coppejans, O.J. (author), Walters, C.L. (author)
The Weibull stress (Beremin, 1983) relates the local first principal stress and plastically strained volume to the probability of fracture. It requires two constants (m, σu) as input, which are generally regarded as material parameters. As the Beremin approach is used in the background to structural analysis rules, the Beremin parameters are now...
conference paper 2018
document
Bijleveld, F.W. (author), Hoogeland, M.G. (author), Walters, C.L. (author), van Bergen, J.W. (author)
Ship owners, including navies, are increasingly sailing ice-infested waters and hence need to know the safety of ship hulls regarding collision with ice. Considerable knowledge exists for modelling failure of the hull in impact situations; however, these methods are either insufficiently precise or too expensive for engineering practice. A...
conference paper 2018
document
Walters, C.L. (author), Bruchhausen, M. (author), Lapetite, J.M. (author), Duvalois, W. (author)
It is sometimes necessary to find the toughness of existing structures without damaging them. Examples of this scenario include situations in which the material is suspected of being brittle or service life extensions. However, fracture testing is inherently destructive. Removing material for Charpy or Crack Tip Opening Displacement (CTOD)...
conference paper 2017
document
Copppejans, O.J. (author), Walters, C.L. (author)
The local approach to modelling ductile tearing is a useful technique to give insight into fracture mechanics. However, applications of the local approach have been stymied by the high cost of finding the parameters that characterize it because of the number of specimens and expensive post-processing that the testing requires. In this paper, a...
conference paper 2017
document
Walters, C.L. (author), Duvalois, W. (author), Bruchhausen, M. (author), Lapetite, J.M. (author)
article 2016
document
Courage, W.M.G. (author), Dragt, R.C. (author), Pijpers, R.J.M. (author), Maljaars, J. (author), Walters, C.L. (author), van der Weijde, G.D. (author)
design driver for Offshore Wind Turbine (OWT) substructures and also has an im-pact on operational costs. During service life, inspections are required to detect fa-tigue cracks at an early stage. These cracks may need to be repaired. The costs of in-spections and repair are high for offshore structures. To reduce the cost of energy, it is...
article 2016
document
Walters, C.L. (author), Alvaro, A. (author), Maljaars, J. (author)
The Fatigue Ductile–Brittle Transition (FDBT) is a phenomenon similar to the fracture ductile to brittle transition, in which the fracture mode of the fatigue cracks changes from ductile transgranular to cleavage and/or grain boundary separation. Fatigue at temperatures below the FDBT has a much different crack growth rate than fatigue above...
article 2016
document
Dekker, R. (author), Walters, C.L. (author)
Localised buckles can occur in crasheswhen compressive stresses are dominant. However, due to their local appearance, they might be overlooked by a finite element analysis, meaning that local failure due to bucklingwill not be predicted. This could, for example, be catastrophic in the case of the crushing of a fuel tank or the impact on a ship...
article 2016
document
Atli-Veltin, B. (author), Dekker, R. (author), Brunner, S.K. (author), Walters, C.L. (author)
Depending on the state of stress, material can fait in a number of different modes during a collision. Three modes are identified here as material separation in the absence of necking, material separation after the onset of necking, and localized buckling/wrinkling. Through a series of case studies, the states of stress present in a collision...
conference paper 2016
document
Dekker, R. (author), Walters, C.L. (author)
Localized buckles can occur in crashes when compressive stresses are dominant. However, due to their local appearance, they might be overlooked by a finite element analysis, meaning that local failure due to buckling will not be predicted. This could, for example, be catastrophic in the case of the crushing of a fuel tank or the impact on a ship...
conference paper 2016
document
Walters, C.L. (author), Dragt, R.C. (author)
Current codes and norms allow for structures to be operated in the transition between ductile and brittle behavior. Further, they often treat the Ductile to Brittle Transition Temperature as a constant even though it is well known to depend on a variety of factors, such as loading rate, constraint, and prior cold deformation. This paper roposes...
conference paper 2016
document
Tang, L. (author), Walters, C.L. (author), van den Heuvel, W. (author), van Daelen, E.C.M. (author)
Failure prediction in crash analyses of ships has traditionally made use of an equation that relates the failure strain to the gage length and material thickness. The equation is derived based on the idea that a neck ( a localization of strain) is a fixed size relative to the thickness and that it can be homogenized over a larger gage section....
conference paper 2015
document
Dragt, R.C. (author), Kraus, J. (author), Walters, C.L. (author)
Simulation of failure in thin-walled structures is critical for the correct determination of crash performance of ships and offshore structures. Typically, shell elements are used, but these elements are not able to adequately capture local failure, especially inside of a neck. This paper addresses these gaps by adapting the Bridgman (1952)...
conference paper 2015
Searched for: author:"Walters, C.L."
(1 - 20 of 40)

Pages