Hadi Baghi

Shear Properties of the Strain Hardening Cementitious Composite Material

AbstractRecently, strain hardening cementitious composite (SHCC) material has been used for the shear strengthening and the structural rehabilitation of reinforced concrete structures. However, the shear behavior of this material has not been yet fully understood due to lack of an appropriate and accurate direct shear test method. This paper aims to investigate the shear properties of the SHCC material. For this purpose, Iosipescu shear test was selected, where loads are applied in antisymmetric four-point bending, assuring a pure shear section at the center of the specimen. A special geometry for the specimen was adopted in order to assure a uniform shear stress distribution in the pure shear section. This experimental test can characterize the shear behavior of SHCC material. The experimental test was simulated by the finite element method (FEM)-based computer program, FEMIX. To predict the average shear stress–sliding response, the shear crack softening diagram, available in the multidirectional fixed ...

Shear Strengthening of Reinforced Concrete T-Beams with Hybrid Composite Plate

AbstractThis paper aims to evaluate the effectiveness of hybrid composite plates (HCPs) technique for the shear strengthening of the reinforced concrete (RC) T cross-section beams. HCP consists of a thin plate of strain hardening cementitious composite (SHCC) reinforced with carbon fiber reinforced polymer (CFRP) laminates. Two HCPs with different CFRP laminates percentage (ρfw=0.08% and ρfw=0.14%) were adopted for the shear strengthening of the beams. The HCPs were bonded to substrate in two different ways. In the first case, the HCPs were bonded using epoxy adhesive, whereas in the second case they were bonded using epoxy adhesive and fixed by mechanical anchors. The effectiveness of this technique was limited by the tensile strength of the concrete cover of the strengthened beams. Therefore, in the second case, mechanical anchors prevented a premature debonding of the HCPs and a certain concrete confinement was applied in the zone of the beam to be strengthened, resulting in favorable effects in terms ...

A design approach to determine the shear capacity of reinforced concrete beams shear strengthened with NSM systems

AbstractThis paper presents a design approach to predict the shear capacity of RC beams strengthened with fiber reinforced polymer (FRP) laminates/rods applied according to the near-surface mounted...

New Shear Strengthening Configurations of Near-Surface- Mounted CFRP Laminates for RC Beams

QREN (through the Operational Program COMPETE) in the scope of the CutInov Project (n. 38780) involving the Clever Reinforcement Company and the Structural Composites Research group of ISISE-Minho University

New Approach to Predict Shear Capacity of Reinforced Concrete Beams Strengthened with Near-Surface-Mounted Technique

The study presented in this paper is a part of the research project 38780, QREN, titled “CutInov – Innovative carbon fibre reinforced polymer laminates with capacity for a simultaneous flexural and shear/punching strengthening of reinforced concrete elements”, co-financed by the European Regional Development Fund (FEDER) through the Operational Program COMPETE. The first author acknowledges the research grant provided by this project.

Shear strengthening of damaged reinforced concrete beams with hybrid composite plates

The study presented in this paper is a part of the research project titled “PrePam –Pre-fabricated thin panels by using advanced materials for structural rehabilitation” with reference number of PTDC/ECM/114511/2009. The first author acknowledges the research grant provided by this project. The authors also thank the collaboration of the following companies: Clever Reinforcement Iberica for providing the CFRP laminates and epoxy, Sika for the sand and adhesive, Grace for the superplasticizers, Dow Chemical Co. for viscous modifying agents, ENDESA Compostilla power station for the fly ash, and Casais for assisting in the execution of the beams

Development of a high-performance concrete deck for Louisiana’s movable bridges: numerical study

This study was sponsored by the Louisiana Transportation Research Center (LTRC). The authors thank the members of the project review committee for their comments and their thorough review of the work performed to date. The authors also thank Lafarge North America for donating Ductal to conduct the material characterization study. The opinions expressed herein are those of the authors and do not necessarily reflect the views of the sponsor.

Experimental and numerical assessment of the shear strengthening effectiveness of hybrid composite plates in reinforced concrete beams

This paper presents numerical and experimental studies on the performance of Hybrid Composite Plates (HCPs) as a shear strengthening technique for reinforced concrete (RC) beams. A HCP is a thin plate of Strain Hardening Cementitious Composite (SHCC) reinforced with Carbon Fiber Reinforced Polymer (CFRP) laminates applied according to the Near Surface Mounted technique (NSM). Due to the excellent bond conditions between SHCC and CFRP laminates, these reinforcements provide the necessary tensile strength capacity to the HCP. However, the shear behavior of SHCC material has not been yet fully understood due to lack of an appropriate and accurate direct shear test method. To characterize the behavior of SHCCs in shear, the Iosipescu shear test setup was used to test several specimens, in which the loads were applied in an antisymmetric four point bending configuration to assure a pure shear section. A special geometry for the specimens was chosen to assure a uniform shear stress distribution in the pure shear section. A numerical model is presented for predicting the strengthening effectiveness of HCPs in reinforced concrete beams. The numerical simulations were performed on FEMIX, a computer program that includes a shear crack softening law to simulate the stress transfer mechanism at the shear crack as the crack widens. The values of the parameters that define the shear crack softening law were derived based on simulations of Iosipescu shear tests performed as part of this study. The results of the numerical models for the reinforced concrete beams strengthened with HCPs are compared with the experimental data obtained for this beams. It is demonstrated that the numerical model can predict fairly well the behavior of reinforced concrete beams strengthened with HCPs. DOI 10.21012/FC9.055 H. Baghi, J.A.O, Barros, F. Menkulasi