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This paper presents a numerical shear stress transfer model for investigating the shear fracture behaviour of strain-hardening cementitious composites (SHCCs) for strengthening reinforced concrete (RC) structures. The model focuses on the transferred shear stress on the crack surface of the SHCC, taking account of the contributions from both the contact stress of the matrix and the bridging stress of the fibres. The numerical results demonstrate that the proposed shear stress transfer model can appropriately evaluate the shear fracture behaviour of SHCCs for RC strengthening, in which the fibre bridging effect on the crack surface of the SHCC has much influence on the shear fracture behaviour of the SHCC strengthening layer. [ABSTRACT FROM AUTHOR]

A numerical approach for evaluating the behaviour of strain-hardening cementitious composites (SHCCs) for reinforced-concrete (RC) seismic strengthening is presented. The method takes account of the seismic tensile strain capacity of SHCCs for RC strengthening, which is affected by the presence of cracks within the RC and varying layer thickness of the SHCC, the shear transfer behaviour of SHCC layers on the crack surface, which is contributed to by both the contact effect and the fibre bridging effect on the crack surface, and the seismic compressive constitutive law of SHCCs. In the numerical approach, a zero-span tensile model is adopted for reflecting the tensile strain capacity of SHCCs for RC strengthening, and a shear stress transfer model is applied for reflecting the respective contributions of both contact stress and fibre bridging stress for shear stress transfer behaviour of the SHCC on the crack surface. The effectiveness of the numerical approach is confirmed through the comparison between the experimental investigation and numerical analysis, in which the numerical result is coincided with the experimental one. [ABSTRACT FROM AUTHOR]

This paper presents a scheme of double-plane shear testing to investigate the shear transmission mechanism of strain-hardening cementitious composite (SHCC) after crack opening; the focus is on the shear stress transfer behaviour on the crack surface of the SHCC, contributed by both the contact effect of the matrix and the fibre bridging effect on the crack surface. The experimental results demonstrate that the transferred shear stress on the crack surface of the SHCC is contributed by both the contact effect of the matrix and the fibre bridging effect on the crack surface until peak shear stress, whereas after the separation of the crack surfaces, it is influenced solely by the fibre bridging effect. It is confirmed that the fibre bridging effect on the crack surface of SHCC has considerable influence in the shear fracture behaviour of SHCC. [ABSTRACT FROM AUTHOR]

Strain-hardening cementitious composites (SHCCs) are an attractive construction material, due to their obvious advantage of large tensile strain capacity with pseudo strain-hardening, whereas this advantage is obviously reduced when SHCC is used for RC strengthening. This study investigated, experimentally and numerically, the localised behaviour of SHCCs for RC strengthening, with a focus on crack elongation performance and the ductility reduction of SHCC for RC strengthening. The numerical investigation was implemented using a proposed scheme that considers the localised behaviour of SHCCs for strengthening RC structures with cracks. The effectiveness of the numerical scheme was confirmed through a comparison of experimental and numerical results. [ABSTRACT FROM AUTHOR]

Strain hardening cementitious composites (SHCCs) have obvious advantages when used to strengthen reinforced concrete (RC) structures - high tensile and compressive strengths, as well as large tensile strain in uniaxial tensile behaviour. However, when used for flexural strengthening of RC members, the ductility of SHCC is reduced and the cracking behaviour of the SHCC strengthening layer varies with different layer thicknesses. In this paper, a zero-span tensile model using a fictitious material is proposed to assess the cracking behaviour of SHCC used for RC flexural strengthening, considering the localised behaviour of the SHCC on the cracked RC substrate member. In the model, the crack in the RC substrate member is represented by an artificial crack formed by two areas of fictitious material. The proposed model can evaluate the cracking behaviour of SHCC layers of varying thickness used for flexural strengthening of RC members. [ABSTRACT FROM AUTHOR]