196,004 research outputs found
FATICA HCF SU UN VIADOTTO A TRAVATA CONTINUA /
No full textFATICA HCF SU UN VIADOTTO A TRAVATA CONTINUA CON METODO DI CALCOLO CHE TIENE CONTO DEL DEGRADO DEL MATERIAL
FATICA E FREQUENZA DI CARICO DEL CLS COMPRESSO
No full textSi analizza la influenza della frequenza con cui si affatica una struttura in calcestruzzo compresso
// Collana STUDI E RICERCHE - Dipartimento di ingegneria strutturale e geotecnica / Università degli studi di Roma "La Sapienza". ROMA: Esagrafica srl (Italy)
CONTRIBUTI ALLO STUDIO DEI FENOMENI DI FATICA SUI VIADOTTI /
No full textDiscussione e risposta ad osservazioni di un Professore non sperimentatore convinto della non esistenza dei fenomeni di fatica.
Valutazione della vita di servizio ad a fatica di un viadotto a impalcato continuo a cassone precompresso. Valutazione degli effetti di fatica mediante la relazione Calzona-Dolara.
Inserimento nel NOTIZIARIO AICAP 11/94
FATICA SU UN VIADOTTO STRADALE A TRAVATA CONTINUA
No full textFATICA SU UN VIADOTTO STRADALE A TRAVATA CONTINUA
// Collana STUDI E RICERCHE - Dipartimento di ingegneria strutturale e geotecnica / Università degli studi di Roma "La Sapienza". ROMA: Esagrafica srl (Italy)
AZIONE TERMICA AMBIENTALE SU UN IMPALCATO CONTINUO A CASSONE /
No full textThe daily weather termal variations influence the tensional state of bridge box girder continuous span. One analize the structure response under two idealized thermal stories
PROVE SPERIMENTALI DI FATICA E FRATTURA METODOLOGIA DELL'ACQUISIZIONE DATI E PRIMI RISULTATI
No full textPROVE SPERIMENTALI DI FATICA E FRATTURA.
METODOLOGIA DELL'ACQUISIZIONE DATI E PRIMI RISULTATI
Estratto da: MATERIALI E STRUTTURE SOGGETTI A CARICHI CICLICI 31.3.1993 // Collana STUDI E RICERCHE - Dipartimento di ingegneria strutturale e geotecnica / Università degli studi di Roma "La Sapienza". ROMA: Esagrafica srl (Italy)
Autorimesse aperte, fuori terra ed a spazio aperto: ingegneria antincendio e progettazione strutturale
No full textUltra-High performance concrete (UHPC) with polypropylene (Pp) and steel Fibres: Investigation on the high temperature behaviour
No full textUltra-high performance concretes (UHPC) are advanced cement-based materials characterised by superior mechanical properties with respect to normal and high-strength concretes; however, their dense and compact matrix can facilitate the onset of spalling at high temperatures. This problem is often coped up by adding polypropylene (PP) fibres to the mix design, alone or with other types of fibres; steel fibres enhance the material's tensile capacity. The paper presents a series of tests on two UHPC types (150 and 180 N/mm2) with PP fibres (0.27% of volume) and variable content of steel fibres (0% to 1.92%), aimed at investigating the residual mechanical properties of the material after high temperature exposure. The experimental results are compared to available research on small UHPC specimens exposed to high temperatures, with dosages in PP fibres from 0.03% to 2%, and in steel fibres from 0 to 3%. The results of this research demonstrate that UHPCs need hybrid fibre reinforcement (PP + steel) to withstand high temperatures, and that the residual strength increases after 200 °C exposure, at all steel fibre dosages; this is in line with literature. Available research also shows that strength loss is possible in hot conditions, as found in the present research, while PP fibres alone do not always prevent the occurrence of spalling in small UHPC samples
Research on the High Temperature Behaviour of Ultra-High-Performance Concrete (UHPC) with Polypropylene (PP) and Steel Fibres
No full textThe research features a series of tests on two types of Ultra-High Performance Concrete (UHPC, 150 and 180 N/mm2) with polypropylene (PP) fibres (0.27% of volume) and variable content of steel (S) fibres (0% to 1.92%), aimed at investigating the residual mechanical properties of the material after high temperature exposure. The results are compared to available research on small UHPC specimens exposed to high temperatures, with PP fibres from 0.03% to 2%, and S fibres from 0 to 3% of volume. The results demonstrate that UHPCs need hybrid fibre reinforcement (PP + S) to withstand high temperatures, and that the residual strength increases after 200 °C exposure, at all steel fibre dosages; this is in line with literature. Available research also shows that strength loss is possible in hot conditions, as found in the present research, while PP fibres alone do not always prevent the occurrence of spalling in small UHPC samples
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