An incremental fracture mechanical analytical approach is described determining the ultimate shear capacity of longitudinally reinforced concrete beams. In practically all respects, including the major assumptions, approach mimicks the computational approach of Gustafsson and Hillerborg based on the fictitious crack…
An incremental fracture mechanical analytical approach is described determining the ultimate shear capacity of longitudinally reinforced concrete beams. In practically all respects, including the major assumptions, approach mimicks the computational approach of Gustafsson and Hillerborg based on the fictitious crack model. It is also similar principle to proposed by Jenq and Shah in which the contributions concrete steel-concrete interaction are superposed to calculate the ........ ., .......... QA..,..., strength. It is shown that the incremental procedure converges a few iterations. The number of iterations depends on how far the ..,.._ .... .,Jl_..., ..... ,_ diagonal tension crack is from load point at the of the nearer it is to the load point, the fewer the iterations. The approach will be found particularly useful by designers who do not access to a finite element package based on the fictitious crack ......... ~.._......,.._, when such a package is available, it will be found useful for ................. ~ .... A,_, estimate of the ultimate shear capacity. 1111 .... ...,,,,"'".._...,,.,""" ..... & Hillerborg 988) proposed a computational technique for cal- -L .. AAAA ....... .., shear strength of longitudinally reinforced beams based ...... ...,.,,,~..., ..... .., crack model (FCM). An approximate analytical approach two-parameter model (Jenq & Shah 1985) was proposed by 989) in order to avoid finite element numerical computations. respects, including the assumptions, this approach mimicks ,..,._,,..,....,...,,,,.,.,it .• ,..'" ... based on the FCM. approach assumes that the ultimate shear strength of reinforced beam is the superposition of the contributions concrete and steel-concrete interaction. In theory, the former can be ,.,_..,_J.JLU."-'""'"--l> from the two parameters KJc (fracture toughness) and CTO De ,.,,.,. .... L .............