Dan Meng, C.K. Lee, Y.X. Zhang* Flexural and Shear Behaviors of Plain and Reinforced Polyvinyl Alcohol-Engineered Cementitious Composite Beams Dan Meng, C.K. Lee, Y.X. Zhang* *Corresponding author Senior Lecturer, Civil Engineering Discipline Coordinator School of Engineering and Information Technology The University of New South Wales, Canberra, ACT 2600, Australia Email: y.zhang@adfa.edu.au; Tel: 612-62688169

Highlights An experimental investigation on the flexural and shear behaviours of PVA-ECC beams using a recently developed PVA-ECC Comparison between the structural behaviour of steel reinforced PVA-ECC beams and RC beams Comparison between the structural behaviour of steel reinforced PVA-ECC beams with and without stirrups Demonstrated the high shear resistance of the PVA-ECC beam, and suggested that shear reinforcement could be reduced when the concrete matrix was replaced by the PVA-ECC

A recently developed PVA-ECC PVA-ECC is known for its significantly improved tensile strain hardening behaviour and multiple microcrackings. Problems and challenges for large-scale applications of PVA-ECC Microsilica sand is more expensive and difficult to obtain compared with local sand Complex social and environmental problems caused by the production of construction materials. Solution: Use of local sand would be preferred A PVA-ECC was developed by the authors using local sand to reduce cost [1] and had a tensile strain capability typically ranging from 0.5-1.0%. [1] Dan Meng, Ting Huang, Y.X. Zhang, C.K. Lee. Mechanical behaviour of a polyvinyl alcohol fibre reinforced engineered cementitious composite (PVA-ECC) using local ingredients. Construction and Building Materials. 2017; 141: 259-270.

Mix design and material properties of the PVA-ECC Table 1 Mix proportions of the developed PVA-ECC Cement Fly ash Sand/Binder Water/Binder HRWR Fibre (vol. %) 1.0 1.2 0.36 0.3 0.01 2.2 Tensile stress-strain relationship Compressive stress-strain relationship Young’s modulus: 18.1 Gpa Compressive strength and corresponding strain: 48.4 MPa and 0.55% Tensile peak strength and corresponding strain: 4.8 MPa and 0.65%

Matrix strain at peak load (%) Experimental program Beam details Beam designation Matrix type Shear reinforcement bar Matrix E (GPa) Matrix fc (MPa) Matrix strain at peak load (%) Design capacity (kN) RC Normal concrete Φ6@100 mm 31.0 45.2 0.28 52.5 RECC PVA-ECC 17.1 47.1 0.58 67.6 RC-NS __ 30.9 49.8 0.30 39.4 RECC-NS 18.6 51.9 0.55 PECC 18.5 46.2 0.51 9.1 Test setup

Experimental results Beams after failure

Experimental results RC beams versus RECC beams

Experimental results RC-NS beams versus RECC-NS beams

Experimental results RECC beams versus RECC-NS beams

Conclusions The flexural behaviour of the RECC beams was significantly improved when compared with the RC beams, with a 14.8% higher load-carrying capacity and an improvement of 103.6% in the corresponding mid-span deflection. RECC-NS beams failed in flexure rather than in shear, exhibiting remarkable shear resistance. The RECC-NS beams showed similar load-deflection behaviour and crack pattern to those of the RECC beams. It is suggested that the number of stirrups could be reduced when the concrete matrix is replaced by the PVA-ECC.