Experimental and numerical analysis of interfacial bonding strength of polyoxymethylene reinforced cement composites

摘要

The objective of this paper is to investigate the interfacial bonding strength of polyoxymethylene (POM) reinforced cement composites through pull-out tests and finite element model (FEM). As comparison with usual materials, the pull-out tests of polypropylene (PP) reinforced cement composites and polyethylene terephthalate (PET) reinforced cement composites are also performed. The pull-out tests are performed in forms of fiber reinforced cement and woven fabric reinforced cement. The woven fabrics contain three different structures, i.e. plain, twill and hybrid. Compared with PP and PET, the results show that POM could form a much stronger interface bonding with cement irrespective of reinforcement form (fiber or woven fabric). Besides, the interfacial bonding strength of woven fabric reinforced cement composite presents a significant structural dependency. The FEM of woven fabric reinforced cement composite is established and the internal mechanism for the structural effect is analysed. Woven fabric comprises two different yarn segments: curved segment and straight segment. During the pull-out process, the curved segment rotates and distorts the weft yarn. Owing to the rotational deformation, the cement surrounding the curved segments damages more seriously. Therefore, a woven fabric with more straight segments could form a stronger interface bonding with cement. (C) 2019 Elsevier Ltd. All rights reserved.