Izvorni znanstveni članak
Experimental study and numerical simulation of the behaviour of concrete dapped-end beams
J. Yolanda Moreno
; Instituto de Ingeniería, Universidad Nacional Autónoma de México, Circuito Escolar, Ciudad Universitaria, 04510 Mexico City, MEXICO
Roberto Meli
; Instituto de Ingeniería, Universidad Nacional Autónoma de México, Circuito Escolar, Ciudad Universitaria, 04510 Mexico City, MEXICO
Sažetak
One of the commonly used advantages in the construction of bridges is the possibility of dividing beams into two prefabricated sections imposing thus a hinge without significantly altering the distribution of internal forces with respect to that of a continuous beam. However, a weakness of this solution is the possibility of premature cracking in the re-entrant corner of the dapped-end beam, which may in turn lead to the infiltration of water. For the purpose of this study, three scaled specimens were built and subjected to service load. The first specimen was reinforced according to the guidelines given in PCI design Handbook [1], a longitudinal post-tension was applied to the second one while diagonal bars were placed in the third specimen. The obtained results allow the conclusion that the post-tensioned specimen had a better behaviour, i.e. the post-tensioning is positively correlated with the reduction of cracking. Three-dimensional nonlinear finite element models were created to simulate the cracking of concrete under service load. To this end, smeared crack and discrete crack approach were adopted. The values for cracking obtained by the numerical models showed satisfactory agreement with the experimental tests. It was concluded that in case the necessary parameters for simulation of cracks are obtained from experimental tests, the discrete crack model can be applied to the study of local fracture in reinforced or prestressed concrete structures.
Ključne riječi
concrete dapped-end beams; discrete crack; smeared crack; cohesive zone model; finite element analysis; post-tension
Hrčak ID:
184916
URI
Datum izdavanja:
23.1.2014.
Posjeta: 538 *