Structures

The Effect of Casting Flow Defects on the Flexural Behavior of 2-way UHPFRC Slabs Investigated by Digital Image Correlation and Magnetic Assessment

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Abstract

Structural applications of Ultra High Performance Fiber Reinforced Concrete (UHPFRC) have been emerging worldwide thanks to the outstanding tensile strength and ductility of this category of materials. From a design point of view, a critical aspect is to guarantee the ductility of the structural response associated to local material non-brittleness, which strongly depends on the fiber dispersion and orientation. This work aims at considering the effect of fiber orientation on the biaxial behavior of UHPFRC slabs for composite bridges. Several square slabs made of UHPFRC were cast by changing the concrete flow direction and the position of internal cold joints. The slabs were tested under biaxial bending under hyperstatic conditions. The fiber orientation was measured by a non destructive method based on the magnetic properties of the composite, while the damage process, with emphasis on the microcrack formation and the crack opening, was measured by 3D digital image correlation. Finally, approaches based on the yield line method were employed to analyze the experimental results with respect to the measured fiber orientation and crack distribution. The results of the present work show the important effect of fiber orientation on the ductility of UHPFRC slabs and the ability of combining magnetic methods and Digital Image Correlation (DIC) analyses to capture those effects.

Keywords: slab, fiber orientation, non-destructive magnetic method, digital image correlation, thin slabs, flow casting defect, Ultra high performance fiber reinforced concrete

How to Cite:

Baril, M., Sorelli, L., Réthoré, J., Baby, F., Toutlemonde, F., Ferrara, L., Faifer, M. & Bernardi, S., (2016) “The Effect of Casting Flow Defects on the Flexural Behavior of 2-way UHPFRC Slabs Investigated by Digital Image Correlation and Magnetic Assessment”, International Interactive Symposium on Ultra-High Performance Concrete 1(1). doi: https://doi.org/10.21838/uhpc.2016.9