. "0"^^ . "2"^^ . "0"^^ . . "2002-01-16+01:00"^^ . . . "Critical stress for crack propagation in concrete."@en . "P(GV103/97/K003), P(KSK1076602), Z(AV0Z2041904)" . "651254" . . "Kritick\u00E9 nap\u011Bt\u00ED pro \u0161\u00ED\u0159en\u00ED trhlin v betonu."@cs . "N\u00E1hl\u00EDk, Lubo\u0161" . . . "Kritick\u00E9 nap\u011Bt\u00ED pro \u0161\u00ED\u0159en\u00ED trhlin v betonu." . "Critical stress for crack propagation in concrete."@en . . . "RIV/68081723:_____/02:07023171!RIV/2003/GA0/A07003/N" . . "Ostrava" . "crack propagation, concrete, interface"@en . . . "Vysok\u00E1 \u0161kola b\u00E1\u0148sk\u00E1 - Technick\u00E1 univerzita Ostrava. Fakulta stavebn\u00ED" . . "7"^^ . "Kritick\u00E9 nap\u011Bt\u00ED pro \u0161\u00ED\u0159en\u00ED trhlin v betonu."@cs . . . . . "Kritick\u00E9 nap\u011Bt\u00ED pro \u0161\u00ED\u0159en\u00ED trhlin v betonu." . "Ostrava [CZ]" . . "2"^^ . "P\u0159\u00EDsp\u011Bvek se zab\u00FDv\u00E1 \u0161\u00ED\u0159en\u00EDm trhlin v betonu. Beton je uva\u017Eov\u00E1n jako dvouf\u00E1zov\u00E9 prost\u0159ed\u00ED. Prvn\u00ED f\u00E1ze (matrice) je tvo\u0159ena cementovou pastou. Druh\u00E1 f\u00E1ze (\u010D\u00E1stice) je tvo\u0159ena zrny kameniva. Existence rozhran\u00ED mezi cementovou pastou a zrny kameniva hraje v\u00FDznamnou roli v p\u0159\u00EDpad\u011B \u0161\u00ED\u0159en\u00ED trhlin v betonu. Lomov\u00E9 chov\u00E1n\u00ED betonu m\u016F\u017Ee b\u00FDt siln\u011B ovlivn\u011Bno existenc\u00ED tohoto rozhran\u00ED a jeho vlastnostmi. V pr\u00E1ci je za podm\u00EDnek platnosti line\u00E1rn\u00ED elastick\u00E9 lomov\u00E9 mechaniky odhadnuta velikost kritick\u00E9ho nap\u011Bt\u00ED pot\u0159ebn\u00E9ho k poru\u0161en\u00ED \u010D\u00E1stice (zrna kameniva). Je studov\u00E1na velikost tohoto kritick\u00E9ho nap\u011Bt\u00ED v z\u00E1vislosti na r\u016Fzn\u00FDch materi\u00E1lov\u00FDch vlastnostech cementov\u00E9 pasty (matrice) a zrn kameniva (\u010D\u00E1stic). Pozornost je v\u011Bnov\u00E1na vlivu Poissonov\u00FDch \u010D\u00EDsel obou f\u00E1z\u00ED na velikost v\u00FDsledn\u00E9ho kritick\u00E9ho nap\u011Bt\u00ED vedouc\u00ED k rozlomen\u00ED zrna kameniva." . "96" . "Probl\u00E9my modelov\u00E1n\u00ED." . "RIV/68081723:_____/02:07023171" . "Concrete is modelled as a two-phase material. Behaviour of a crack with its tip on the interface between two different materials - hardened cement paste (matrix) and aggregate (particle) - is studied. In contrast to cracks in homogeneous materials the stress singularity for a crack terminating at the interface is of the type r -lambda, where the value of the stress singularity exponent, lambda, is in the interval 0 < lambda < 1. Than classical fracture mechanics theory and criterion cannot be applied. In the paper a new stability criterion is used to estimate the critical stress for the intersection of coarse aggregate particles."@en . . . "[28959F8B3679]" . "Kn\u00E9sl, Zden\u011Bk" .