; BCOh+'0HP|
$TU Delft Repository search results0TU Delft Repository search results (max. 1000)TU Delft LibraryTU Delft Library@v@v՜.+,0HPX`hp
x
WorksheetFeuilles de calcul
B=%r8X"1Calibri1Calibri1Calibri1
Calibri 83ffff̙̙3f3fff3f3f33333f33333.L'TU Delft Repositoryg T'uuidrepository linktitleauthorcontributorpublication yearabstract
subject topiclanguagepublication type publisherisbnissnpatent
patent statusbibliographic noteaccess restrictionembargo datefaculty
departmentresearch group programmeprojectcoordinates)uuid:e4da9247-c869-440d-a525-93a65de0773eDhttp://resolver.tudelft.nl/uuid:e4da9247-c869-440d-a525-93a65de0773ehA mesoscale modelling perspective of cracking process and fracture energy under high strain rate tensionLu, Y.; Xu, J.; Weerheijm, J.dThis paper presents a numerical modelling study on the simulation of the cracking process and fracture energy in concrete under high strain rate. To capture the stress wave effect and the damage evolution at the meso-length scale, both a homogeneous model with a millimetre-resolution mesh and an explicit heterogeneous mesoscale model with random polygon aggregates are employed. The tendency of development of a) discrete multiple cracks, and b) spread tensile damage across adjacent element layers, in the high strain rate tension regime is scrutinised. This phenomenon generally gives rise to an increase in the dynamic fracture energy, which is consistent with experimental observations. Relative comparison between the homogeneous and heterogeneous mesoscale simulations suggests a sensible effect of the mesoscopic heterogeneity in the dynamic fracture process.
Mechatronics, Mechanics & Materials; EBP - Explosions, Ballistics & Protection; TS - Technical Sciences; Defence Research; Architecture and Building; Defence, Safety and Security; Concrete; Dynamic tension; Fracture energy; High strain rate; Mesoscale model; Dynamic fracture process; Dynamic tension; Experimental observation; High strain rates; Meso-scale models; Mesoscale modelling; Mesoscale simulation; Mesoscopic heterogeneity; Concrete buildings; Concrete construction; Cracks; Fracture energy; Strain rate; Concretesenconference paperxSponsors: INSTRON; ZWICK IBERICA Equipos de Ensayos S.L.; Tonitecnik; Sistemas de Ensayo de Materiales S.A. (SEM); RUMUL)uuid:289b985a-49db-4094-98f7-ab184bbc49b9Dhttp://resolver.tudelft.nl/uuid:289b985a-49db-4094-98f7-ab184bbc49b9ADynamic tensile resistance of concrete - Split hopkinson bar test%O~bolt, J.; Weerheijm, J.; Sharma, A.The behavior of concrete structures is strongly influenced by the loading rate. Compared to quasi-static loading, on meso and macro-scale concrete loaded by impact loading acts in a different way. First, there is a strain-rate influence on strength, stiffness, ductility, and, second, there are inertia forces activated which influence the resistance and failure mode of concrete structure. The experimental and theoretical studies show that the influence of loading rate on tensile behavior of concrete is relatively strong. In dynamic testing the split Hopkinson bar (SHB) is used to measure concrete tensile resistance. The results of the experimental measurements show that after reaching some critical strain rate tensile resistance progressively increases with increase of strain rate. The questions discussed in the paper are: (i) what is the reason for progressive increase of tensile resistance? and (ii) can the resistance be attributed only to material strength or are there some other effects? To answer these questions the numerical analysis on a simple elastic-cohesive FE model is carried out. Moreover, simulation of the compressive pulse in a concrete bar, which is reflected from the free end-surface of the bar and causes tensile fracture, is carried out for different loading rates. The evaluation of the results clearly shows that the progressive increase of tensile resistance (apparent strength) can be attributed to structural inertia of the fracture zone, which is invoked by cracking of concrete and is not to the true material strength. It is shown that the size of the fracture process zone significantly influence apparent strength. Similar as the true strength it is also discussed that with the increase of strain rate concrete fracture energy does not increase progressively.Architecture a<Und Building; Concrete; Dynamic fracture; Finite elements; Hopkinson bar; Microplane model; Rate sensitivity; True and apparent strength; Dynamic fractures; Hopkinson bar; Microplane models; Rate sensitivity; True and apparent strength; Bars (metal); Concrete buildings; Concrete construction; Concrete testing; Finite element method; Fracture; Fracture mechanics; Strain rate; Strength of materials; Tensile testing; Concretes
*+&ffffff?'ffffff?(?)?"dXX333333?333333?U}}}}}}}}}} }
}}}
}}}}}}}}}}}}
t@
zomΡB
!
"
#
$t@
%
&
zomΡB
!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~>@ddyKyKhttp://resolver.tudelft.nl/uuid:e4da9247-c869-440d-a525-93a65de0773eyKyKhttp://resolver.tudelft.nl/uuid:289b985a-49db-4094-98f7-ab184bbc49b9gg
Root Entry Fvv@SummaryInformation( F<Workbook F@|DocumentSummaryInformation8 F
!"#$%&'()*+,-./0123456789:;<=>?@A