Abstract

The crack formation, propagation and failure mechanism of concrete are very complex. Incorporation of fibers complicates it further, alters the damage characteristics of concrete. There is a consistent effort to impart the strain hardening properties, for which the special type of chemical fibers (Polyvinyl alcohol, PVA) is found to be very promising. Presently, an attempt has been made to understand the damage mechanisms of PVA fibers incorporated concrete (with three fibre dosages (0%, 1%, 2%) subjected to flexural loading using both contact (Acoustic Emission, AE) and noncontact (Digital Image Correlation, DIC) techniques. The advantages of AE which provides information on internal cracking and DIC which provides surface crack characteristics information are suitably exploited in this study. It was found that the combined use of both techniques has the potential to investigate the crack bridging phenomenon, to analyse the damage progression during loading, and to identify the critical failure mechanism and damage classification.

摘要

混凝土裂缝的形成、扩展和破坏机理非常复杂。纤维的掺入使其进一步复杂化，改变了混凝土的损坏特性。人们一直在努力赋予应变硬化性能，为此发现特殊类型的化学纤维（聚乙烯醇，PVA）非常有前途。目前，已经尝试了解 PVA 纤维掺入混凝土（三种纤维剂量（0%、1%、2%）在使用接触（声发射，AE）和非接触（数字图像Correlation, DIC) 技术 本研究适当地利用了提供内部裂纹信息的 AE 和提供表面裂纹特征信息的 DIC 的优点。