Analysis of influence of concrete element format and properties steel fibers on flexural toughness

摘要

Concrete characterizing studies with steel fibers starting from the assay of the traction on flexural of prisms to obtain the toughness flexural have being done to the parameterization of the mechanic behavior of concrete pipes with steel fibers. The study aim is to adjust curves modeling the toughness estimates to the flex on concrete pipes in function to the toughness flexural on prims, both with steel fibers randomly oriented and moreover verify if there is or there is not significant statistic difference among toughness average to flexural when compared to the concrete element form (pipe or prism), and the priorities of steel fibers: Form Factor (65 or 80), State (free or joined to the basis comb) and theoretical fiber consumptions (0,25% or 0,38% or 0,50%). Curves were adjusted modeling the concrete pipe toughness with steel fibers in function of prism flexural toughness, being possible to observe that larger is the prism flexural toughness the larger will be the pipe flexural toughness. The analysis of variance was used to evaluate the existence or not of significant statistic difference among double or triple or quadruples associations. It was individually found that there is not significant statistic difference among the average values of toughness flexural, when compared concrete elements forms, however, there is significant statistic average values of toughness flexural when compared: (i) Form Factor; (ii) State and (iii) Theoretical Fiber Consumption. There was influence on the average values of flexural toughness when we make associations among the different levels of form factors, state and theoretical consumptions on fibers.