Fracture studies on synthetic fiber reinforced cellular concrete using acoustic emission technique

• Published in: Construction & building materials Vol. 169; pp. 100 - 112
• Main Authors: Rasheed, M. Abdur, Prakash, S. Suriya, Raju, Gangadharan, Kawasaki, Yuma
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 30.04.2018; Elsevier B.V
• Subjects: Acoustic emission; Acoustic emission testing; Analysis; Concrete cracking; Crack propagation; Fiber reinforced concrete; Fracture (Materials); Fracture behavior; Health monitoring; Hybrid fibers; Mechanical properties; Methods; Non-destructive testing; Polyolefin fibers; Properties; India; Health monitoring; Acoustic emission; Non-destructive testing; Fracture behavior; Crack propagation; Hybrid fibers; Polyolefin fibers
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2018.02.157

•Fracture behavior of hybrid fiber reinforced CLC is studied using acoustic emission (AE).•Synthetic fibers improved the fracture behavior of CLC.•Hybrid fibers showed better performance compared to only macro-structural fibers.•Three dimensional source location of cracks is carried out based on the AE events.•AE energy correlates with fracture energy. It increases with increase in fiber dosage.•Crack width can be measured indirectly through the number of AE hits observed. Cellular lightweight concrete (CLC) is increasingly used for low strength non-structural and structural applications. The effects of synthetic fiber reinforcement on the fracture behavior of CLC is investigated. In particular, acoustic emission (AE) technique is employed to study the influence of macro (structural), micro polyolefin synthetic fibers and their combinations on the fracture behavior of CLC beams. Notched fiber reinforced CLC beams were tested to study the crack initiation and propagation characteristics using AE sensors. Different AE parameters are correlated with the crack growth and damage accumulation. An attempt has been made to correlate the crack mouth opening displacement (CMOD) with the number of AE hits. The variation of cumulative acoustic energy release of the cracks is studied with respect to applied load and CMOD. Three dimensional source location of cracks is carried out based on the AE events picked by the sensors bonded to the CLC specimens. The analysis of AE results indicates that the crack source location identification from AE is consistent with the actual crack development. Analysis of AE signals reveal that the CLC matrix cracking produces signals with less number of hits that lie in the notched plane in bending. Moreover, the signals from the post peak regime correspond to more number of hits which tend to be scattered around the plane of notch due to the fiber pull out.