STUDY ON BENDING PERFORMANCE AND MECHANISM OFFIBER REINFORCED CEMENTITIOUS COMPOSITES

Abstract

Abstract: To study the bending properties of fiber reinforced cementitious composite, five groups of specimens with different PVA fiber content were studied by four-point bending test. The experimental results show that the fiber content has a significant effect on the bending properties of specimens. Appropriate amount of fiber can significantly improve the brittleness of specimens, and crack is small and dense. When the fiber volume V_f≤2.0%, the initial cracking bending strength, peak bending strength, equivalent bending strength and toughness index increase with the increase of fiber content. For specimens with V_f=2.5%, the flowability is poor and some fiber agglomerates. As a result, the bending strength of specimens with V_f=2.5% is lower than specimens with V_f=2.0%. Combined with the load-deflection curve, the mechanism of fiber in the composite was qualitatively analyzed by scanning electron microscope, and the factors affecting the fiber bridging effect were studied.

Key words: polyvinyl alcohol (PVA) fiber, fiber reinforced cementitious composites, bending strength, toughness index, scanning electron microscope (SEM)

CLC Number:

TB332

GONG Hong-wei, JIANG Shi-yong, CHEN Jin, TAO Shuai. STUDY ON BENDING PERFORMANCE AND MECHANISM OFFIBER REINFORCED CEMENTITIOUS COMPOSITES[J]. Fiber Reinforced Plastics/Composites, 2019, 0(10): 19-25.

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