Title:
Characterization and Prediction of Microcracking in Reinforced UHPFRC Beams under Bending
Author(s):
Turgeon-Mallette, V.; Sorelli, L.; Conciatori, D.; Réthore, J.
Publication:
Symposium Paper
Volume:
343
Issue:
Appears on pages(s):
391-400
Keywords:
Ultra-High Performance Fiber Reinforced Concrete (UHPFRC), Micro-cracks, Crack Width, Digital Image Correlation (DIC), Four Point Bending Test
DOI:
Date:
10/1/2020
Abstract:
The capacity of Ultra-High Performance Fiber Reinforced Concrete (UHPFRC) to develop
multiple micro-cracks instead and delay the localization of major cracks has great impact on
the permeability and durability at serviceability state. In order to assess the durability of
reinforced UHPFRC structures or rehabilitation layers, methods that accurately predict the
microcrack width are necessary. This work aims at assessing the accuracy of some current
analytical models to predict the crack width and growth of reinforced UHPFRC beam in
bending by means of Digital Image Correlation (DIC) analysis of 4-point bending tests. DIC
analysis was successfully employed to estimate the microcrack width and their spacing during
loading. In particular, the following methods for predicting the growth of cracks of a
reinforced FRC member are considered: (i) Eurocode 2; (ii) RILEM TC 162-TDF; (iii) the
one proposed by Moffatt; (iv) the one proposed by Deluce. As expected Eurocode crack
model overestimates the crack width as it does not consider the fiber contribution. RILEM
and Moffatt models well predict the maximum crack width, but Deluce method is the most
accurate to predict the mean crack width. The estimation of the crack spacing seems to the be
critical factor which may require further improvement, especially for the crack spacing at
serviceability states.