Naslov
Assessment of Toughness of Concrete Subject to Elevated Temperatures from Complete Load-Displacement Curve - Part II: Experimental Investigations

Autori
Zhang, B. ; Bićanić, Nenad ; Pearce, C.J. ; Balabanić, Gojko

Izvornik
ACI Materials Journal (0889-325X) 97 (2000), 5; 556-566

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
curing; strength; toughness

Sažetak
In Part I of this paper six energy- and deformation-based toughness indexes were summarised and derived for assessing the concrete toughness based on a two-point complete load-displacement relationship compromising parameters such as load, characteristic displacements, and geometric coeficients, by considering the effect of self-weight of the beam specimen under three-point bending. In this paper, the effects of heating temperature, exposure time, and curing age on the fracture and toughness of concrete were experimentally investigated by conducting three-point bending tests on a total of 55 notched plain concrete beams that had been preheated at temperatures between 100C and 600C over varied exposure times up to 168 h and for four ages ranging from 7 to 90 days. The relationships of these parameters with heating scenarios and curing ages were established. Thus, six toughness indexes could be used to quantitatively assess the toughness of concrete in varied heating scenarios and curing ages. A higher heating teperature always led to a larger toughness. A longer exposure time also led to a larger toughness, but such an effect was more significant at the early exposure age under 12 h, and became weaker thereafter. A longer curing age led to a lower toughness in the first 28 days and did not significantly affect concrete toughness after 90 days.

Izvorni jezik
Engleski

Znanstvena područja
Građevinarstvo

POVEZANOST RADA