Shear transfer mechanism in reinforced engineered cementitious composite (ECC) beams: Quantification of Vs and Vc. (15th June 2022)

• Record Type: Journal Article
• Authors: Gu, Dawei; Pan, Jinlong; Mustafa, Shozab; Huang, Yitao; Luković, Mladena
• Is Part Of: Engineering structures. Volume 261(2022)
• Publication Date: 2022-06-15
• Subjects: Engineered Cementitious Composite (ECC) -- Strain Hardening Cementitious Composite (SHCC) -- Shear -- Stirrup; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2022.114282
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: An innovative testing method consisting of continuous strain quantification along the stirrups and longitudinal reinforcement was used in shear tests of reinforced concrete, mortar and engineered cementitious composite (ECC) beams. By the strain measuring system, the shear resistance coming from the matrix ( V c ) and from the transverse reinforcement ( V s ) in beams can be accurately evaluated. Abstract: To enhance the structural and seismic resistance, as well as durability of concrete structures, an ultra ductile fiber reinforced cementitious composites called Engineered Cementitious Composite (ECC), also known as Strain Hardening Cementitious Composite (SHCC), was developed. ECC has a similar compressive and tensile strength to conventional concrete, but it exhibits a pseudo-strain-hardening behaviour under uniaxial tension with excellent crack control ability. The ultimate tensile strain of ECC can reach 3–12%, which is 300–1200 times higher than that of concrete. It is reported that ECC can also exhibit at least twice as high shear carrying capacity compared to traditional concrete, signifying a potential to use ECC material in shear-resistance elements. However, the shear resisting mechanism of reinforced ECC (R/ECC) members is still not clear. In most existing codes and models, the shear strength of reinforced structural members ( V u ) is divided into two parts, i.e., shear resistance coming from the matrix ( V c ) and from the transverse reinforcement ( V s ). To quantify accurately V c and V s and also their development throughout the loading, a well-designed testing method consisting of continuous strain quantification along the stirrups, was used in this research. Six steel reinforced beams incorporating different matrix (ECC, concrete and mortar) were tested under four-point bending. The test results indicated that V c changed continuously with the propagation of shear crack, whereas the stirrups that crossed the critical shear crack, did not always yield at the ultimate shear resistance.