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Strain-hardening cementitious composites (SHCC) are an attractive construction material with obvious advantages of large strain capacity and high strength, as well as excellent workability and easy processing using conventional equipment. Moreover, SHCC can be designed with varied mix proportions in order to satisfy various requirements and expectations to overcome the shortages of existing construction materials. However, the behavior of SHCC in the structural application is varied from that of SHCC material, which is reviewed and presented in this paper, focusing on the flexural and shear behavior of the SHCC member and the SHCC layer used for strengthening reinforced concrete (RC). The reviewed results demonstrate that both the zero-span tensile behavior of the stress concentration and the uniaxial tensile behavior of the bending effect can influence the crack propagation patterns of multiple fine cracks in the SHCC strengthening layer, in which the crack distribution within the SHCC layer is limited near the existing crack in the RC substrate member in the zero-span tensile behavior. Moreover, the crack propagation patterns of the SHCC strengthening layer are changed with varied layer thicknesses, and the SHCC strengthening layer, even with a small thickness, can significantly increase the shear load carrying capacity of the shear strengthened RC member. This work provides the foundations for promoting SHCC material in the structural application of repairing or retrofitting concrete structures. [ABSTRACT FROM AUTHOR]

This paper presents an experimental investigation into the shrinkage behavior of strain‐hardening cementitious composite (SHCC), which focuses on the influences of varied ingredients in mix proportions and curing condition. The experimental results confirm that the shrinkage strains of SHCC are obviously influenced by the investigated ingredients of SHCC, in which expansion agent can induce expansion strain for nominally reducing the shrinkage strains of SHCC, the shrinkage strains of SHCC's matrix are decreased with increasing fiber volume content and water‐to‐binder ratio, whereas those are increased with increasing silica‐fume‐to‐binder ratio. Moreover, the curing condition has significant influence for the shrinkage behavior of SHCC, and water curing can significantly reduce the shrinkage strains. This work provides experimental foundations for shrinkage behavior of SHCC. [ABSTRACT FROM AUTHOR]

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]

Strain hardening cementitious composite (SHCC) is an attractive construction material used for reinforced concrete (RC) strengthening, and a simplified method has been previously proposed for evaluating the behavior of SHCC flexural strengthening RC member (Zhang, Engineering Fracture Mechanics 2014; 121–122: 11–27), whereas the load carrying capacity of strengthened RC member is over-estimated using the simplified method. In this study, a numerical approach improved from the aforementioned method is presented for accurately evaluating the behavior of SHCC flexural strengthening RC member, considering the influence of the tensile strain capacity of SHCC, presence of localized concrete cracks and varying SHCC layer thickness, in which a zero-span tensile model with fictitious material is adopted to obtain the average tensile behavior of SHCC layer for strengthening RC member with crack. The effectiveness of the improved numerical approach is confirmed thorough the comparison between experimental and numerical investigations. [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]

This paper presented a experimental investigation into the advantage of RC member with shear strengthening using strain hardening cementitious composites (SHCC), focused on the crack pattern of SHCC strengthening layer and its obvious advantage for increasing the shear load carrying capacity of the strengthened RC member. Especially, the shear failed SHCC member was also adopted to reflect the reduced multiple fine crack distribution in SHCC strengthening layer. Moreover, the contributions of matrix and reinforcing fiber for shear load carrying capacity of SHCC strengthening layer were also calibrated respectively, and the shear load carrying capacity of SHCC strengthening layer was assumed as the sum of load carried by matrix and reinforcing fiber. This work provided experimental foundations for RC member with shear strengthening using SHCC. [ABSTRACT FROM AUTHOR]