Effect of different PVA and steel fiber length and content on mechanical properties of CaCO&lt;sub&gt;3&lt;/sub&gt; whisker reinforced cementitious composites

C Xie,M Khan,L Li,M Cao

doi:10.3989/mc.2019.12918

Abstract

In this paper, calcium carbonate (CaCO3) whisker as a fiber reinforcement is mixed with steel and PVA fiber to form a multiscale hybrid fiber reinforced cementitious composites (MHFRCC). ASTM standard and post-crack strength techniques are performed to evaluate the mechanical properties of MHFRCC. The 1.25 % long steel fiber, 0.55 % short PVA fiber and 2.0 % CaCO3 whisker specimens showed the best flexural behavior before L/600 deflection. However, 1.5 % long steel fiber, 0.4 % long PVA fiber and 1.0 % CaCO3 whisker specimens presented better crack resistance after L/600 deflection. It is revealed that flexural parameters increase as comprehensive reinforcing index increase. The result showed that the CaCO3 whisker and short PVA fiber provided crack resistance effect at micro-scale and mainly play a dominate role in inhibiting micro-cracking. However, long steel fiber and long PVA fiber showed a better bridging effect of macro cracks at a large deflection.

Highlights

In this paper, calcium carbonate (CaCO3) whisker as a fiber reinforcement is mixed with steel and PVA fiber to form a multiscale hybrid fiber reinforced cementitious composites (MHFRCC)
The result showed that both compressive strength and flexural performance of MHFRCC are significantly improved showing the multiple cracking behavior
The purpose of this study is to explore the effect of steel-PVA fiber lengths and contents on the overall flexural performance of CaCO3 whisker reinforced cementitious composites

Summary

Introduction

Calcium carbonate (CaCO3) whisker as a fiber reinforcement is mixed with steel and PVA fiber to form a multiscale hybrid fiber reinforced cementitious composites (MHFRCC). The 1.25 % long steel fiber, 0.55 % short PVA fiber and 2.0 % CaCO3 whisker specimens showed the best flexural behavior before L/600 deflection. 1.5 % long steel fiber, 0.4 % long PVA fiber and 1.0 % CaCO3 whisker specimens presented better crack resistance after L/600 deflection. Long steel fiber and long PVA fiber showed a better bridging effect of macro cracks at a large deflection. La mezcla con 1,5% de fibra larga de acero, 0,4% de fibra corta de PVA y 1,0% de filamento de CaCO3 presentó la mejor resistencia a fisuración tras el valor de flecha L/600. It was found that there existed synergistic effect among steel fiber, polypropylene fiber and carbon fiber

Objectives

Findings

Discussion

Conclusion