Effect of Initial Notch-to-Depth Ratio on Fracture Properties of Steel Fiber Reinforced Concrete

Abstract

Abstract: In order to study the effect of the initial notch-to-depth ratio on the fracture properties of steel fiber reinforced concrete, the fracture toughness tests for steel fiber reinforced concrete with different initial notch-to-depth ratios (0.1, 0.2, 0.3) were carried out and the fracture parameters were calculated. By combining acoustic emission (AE) and digital image correlation (DIC) techniques, the variation law of AE energy and full-field strain during fracture development was analyzed. The results show that the fracture toughness of steel fiber reinforced concrete decreases with the increase of the initial notch-to-depth ratio. When the initial notch-to-depth ratio of steel fiber reinforced concrete reaches 0.3, the fracture properties begin to decrease rapidly. The fracture process of steel fiber reinforced concrete is divided into elastic-plastic stage, stable crack propagation stage and fracture stage according to AE energy. With the increase of the initial notch-to-depth ratio, the duration of elastic-plastic stage decreases. The analysis results of DIC show that the prefabricated crack tip produces a large stress concentration and the transverse strain of the crack is large during the whole loading process. The research results reveal the crack development mechanism of steel fiber reinforced concrete, which provides theoretical support for its engineering application.

Key words: initial notch-to-depth ratio, steel fiber reinforced concrete, fracture property, acoustic emission, digital image correlation

CLC Number:

TU528

YANG Xiaohua, LUO Tao, LIU Xiaojian, YE Ermulati. Effect of Initial Notch-to-Depth Ratio on Fracture Properties of Steel Fiber Reinforced Concrete[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2022, 41(10): 3465-3474.

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