The experimental program reported in this paper was planned to investigate the sensitivity of lightly reinforced concrete beams to the shape of the cross-section and to the rebar arrangement. Twenty-four micro-concrete reinforced beams were tested; these were rectangular and T…
The experimental program reported in this paper was planned to investigate the sensitivity of lightly reinforced concrete beams to the shape of the cross-section and to the rebar arrangement. Twenty-four micro-concrete reinforced beams were tested; these were rectangular and T beams reinforced with one, two or three rebars aligned horizontally or vertically. The concrete mechanical properties were all obtained from independent tests. Likewise, experimental errors due to material heterogeneity or incorrect set-up of the tests were minimized to ensure a high lever of control during the execution of the program. The experimental results exhibit maximum load shape effect, i.e. the maximum load does not vary as no- tension hypothesis indicates. Beams in which rebars are aligned horizontally show a secondary load peak after cover cracking, while a vertical arrangement of the rebars provokes more energy dissipation and duc- tility in the post-peak response.