A study on avalanches of early age basalt fiber reinforced concrete beams during flexure

In this work, stress variations during flexure of early age basalt fiber reinforced concrete beams were studied using high resolution temporal measurements. An experimental system was created to collect stress-time curves at 100 kHz sampling rate so that temporal profiles of stress variations were analyzed in detail. Stress drops were modeled as avalanches resulting from interactions between basalt fibers and cementitious matrices. Four-point bending tests at different loading rates were conducted to investigate avalanches during flexure of beams with different fiber volume fractions. Good agreement was obtained between measured avalanche statistics or dynamics and predictions from the mean field model. Different types of avalanches were detected during the flexure of basal fiber reinforced concrete beams, including avalanches with limited size and durations collapsed onto the scaling regime in the logarithmic scale, avalanches with an incubation period before stress drops beyond the scaling regime and giant avalanches occurred at the fracture of bottom concrete. Observations of different avalanche types disclosed the critical failure evolution during flexure of basalt fiber reinforced beams, which could lead to the creation of durable ecofriendly fiber-reinforced concrete structures. (c) 2020 Elsevier Ltd. All rights reserved.

Automated summary

This study investigated stress variations during flexure of early age basalt fiber reinforced concrete beams using high resolution temporal measurements. Different types of avalanches were detected, and good agreement was obtained between measured avalanche statistics or dynamics and predictions from the mean field model.