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This paper investigates the mechanical properties of engineered cementitious composites (ECC) in terms of compressive strength and flexural behaviour. A new version of ECC made of cement, ground granulated blast-furnace slag (GGBS), local sand, polypropylene (PP) fibers, water and superplasticizer (SP) was employed in this study. Few series of ECC mixtures were designed, cast, and tested in compression and flexural after 28 days of curing. The effect of the fiber content and sand content were studied in different cement-GGBS combination. Compression test results indicated that all ECC mixtures obtained at least 1.8 times compressive strength compared to normal concrete. They also demonstrated more ductile flexural behavior compared to normal concrete from three-point bending test. Increasing fiber content from 1.5% to 2.0% and 2.5% has negative effect on compressive strength but significantly improved modulus of toughness of ECC mixtures. The compressive strength of ECC was reduced when the sand to binder ratio adjusted to 0.4 and 0.6. The flexural behaviour of ECC was slightly improved with the increasing of sand content.

The feasibility of using engineered cementitious composites (ECC) in joint cores of reinforced-concrete (RC) beam–column sub-assemblages as a means to enhance seismic behaviour is evaluated. Four RC beam–column sub-assemblages are constructed and tested under lateral cyclic loading. One RC beam–column sub-assemblage with normal concrete in the joint and one RC sub-assemblage with ECC in the joint are designed to gravity loads; neither type has transverse reinforcement in the joint core. Similarly, one RC sub-assemblage with normal concrete in the joint and one with ECC in the joint are designed for seismic provisions, but the latter has no transverse reinforcement in the joint. The test programme thereby allows direct comparison of the structural performance of ECC joints with concrete joints for beam–column sub-assemblages for both gravity and seismic design situations. Results show that the use of ECC joints significantly changes the behaviour of the joint from brittle to ductile. Both ECC specimens exhibit superior damage tolerance, with limited shear distortion and multiple fine cracks in the joints, even though no transverse reinforcement is provided in the joint. Moreover, specimens with ECC joints demonstrate improved bond behaviour in early loading cycles.

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This paper evaluates the mechanical performances of green engineered cementitious composites (ECC) by means of compressive strength and flexural behaviour. Green ECC made of cement, ground granulated blast-furnace slag (GGBS), river sand or recycled concrete fine (RCF), polypropylene (PP) fiber, water and superplasticizer (SP) was employed in this study. Compression test result implies that green ECC incorporating either sieved river sand or sieved RCF (below 600 μm) in series G60 and G70 exhibited greater compressive strength compared with green ECC with unsieved river sand. In series G80, compressive strength of green ECC was not affected by RCF content. Flexural stress-mid deflection curves demonstrated that all green ECC specimens performed more ductile compared to normal concrete as they undergone large deformation capacity after the first cracking strength. Both compression and flexural tests suggested that mixture G80SRCF0.4 containing large amount of sieved RCF and least amount of cement is the best green ECC mixture in this study.

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