Flexural behaviour of steel composite beams encased by engineered cementitious composites

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.

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Numerical modelling of engineered cementitious composites-concrete encased steel composite columns

Journal of Constructional Steel Research ◽

10.1016/j.jcsr.2020.106082 ◽

2020 ◽

Vol 170 ◽

pp. 106082

Author(s):

M.K.I. Khan ◽

C.K. Lee ◽

Y.X. Zhang

Keyword(s):

Numerical Modelling ◽

Cementitious Composites ◽

Engineered Cementitious Composites ◽

Composite Columns ◽

Steel Composite

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Study on Flexural Behaviour of Box Section Bamboo-Steel Composite Beams

Advances in Civil Engineering ◽

10.1155/2020/8878776 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

Qifeng Shan ◽

Jialiang Zhang ◽

Keting Tong ◽

Yushun Li

Keyword(s):

Bearing Capacity ◽

Safety Margin ◽

Composite Beams ◽

Experimental Results ◽

Flexural Stiffness ◽

Flexural Behaviour ◽

Box Section ◽

New Type ◽

Steel Composite ◽

Thin Walled

To take full advantages of the bamboo and cold-formed thin-walled steel, a new type of box section beam combined with bamboo and steel channel was proposed in this paper. Five composite beams with different parameters were tested to evaluate the effects of bamboo plywood thickness of composite beams and thickness and sectional dimension of steel channel. The results of experiment showed that the proposed composite beams exhibited excellent flexural bearing capacities and stiffness. The increase of bamboo plywood thickness and sectional dimension of steel channel could improve bearing capacity and flexural stiffness of composite beams, while the increase of steel thickness could enhance the bearing capacity and safety margin of composite beams. Furthermore, a new method to predict the deformation and bearing capacities of composite beams was proposed and matched well with the experimental results.

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