@article{kazem_kazem_ghahremannejad_vosoughi_hosseini_ghafory-ashtiany_2020, title={Investigation of seismic rehabilitation of steel buildings with semi-rigid connections}, volume={173}, ISSN={["1751-7702"]}, DOI={10.1680/jstbu.17.00192}, abstractNote={ The Khorjinee connection is a special connection that was widely used in the construction of low-rise steel structures in Iran before the national seismic code was established. However, catastrophic experiences from recent earthquakes have shown that these connections are highly vulnerable to seismic loads. In fact, it is recognised that such connections should be classified as non-seismic, semi-rigid connections with unknown rotational stiffness. As a result of this issue, many structures with these connections may need to be rehabilitated to ensure their safety in future earthquakes. In this study the dynamic properties of a half-scale model of a four-storey steel structure with Khorjinee connections were determined by a forced vibration test. The structure was then separately rehabilitated by means of four different bracing configurations (X bracing, chevron bracing, eccentrically braced frames (EBFs) and knee braces) and the structural responses were investigated. The results, which include the natural frequencies, mode shapes and damping ratios for each case, present a realistic approach to enable engineers to select the best way of strengthening steel structures with Khorjinee connections according to diverse structural limitations. The structural displacement ratios were found to be significantly larger in structures with EBFs and knee bracing systems when the number of braced spans is high compared with the first mode. }, number={2}, journal={PROCEEDINGS OF THE INSTITUTION OF CIVIL ENGINEERS-STRUCTURES AND BUILDINGS}, author={Kazem, Hamid and Kazem, Hossein and Ghahremannejad, Masoud and Vosoughi, Payam and Hosseini, Farshid and Ghafory-Ashtiany, Mohsen}, year={2020}, month={Feb}, pages={99–108} }
 @article{kazem_zhang_rizkalla_seracino_kobayashi_2018, title={CFRP shear strengthening system for steel bridge girders}, volume={175}, ISSN={["1873-7323"]}, DOI={10.1016/j.engstruct.2018.08.038}, abstractNote={This paper presents an investigation undertaken to study the effectiveness of using small-diameter CFRP strands for shear strengthening of steel bridge girders. The study includes a comprehensive experimental program to study effects of the CFRP reinforcement ratio and orientation of the strands. An analytical model, calibrated by the experimental tests, was used to provide design recommendation. Results of the study showed that the proposed strengthening system is effective in increasing the shear capacity of steel bridge girders and there was no sign of CFRP debonding or rupture failure commonly observed by CFRP laminates up to approximately 80% of the steel yield stress.}, journal={ENGINEERING STRUCTURES}, author={Kazem, Hamid and Zhang, Ye and Rizkalla, Sami and Seracino, Rudolf and Kobayashi, Akira}, year={2018}, month={Nov}, pages={415–424} }
 @article{kazem_rizkalla_kobayashi_2018, title={Shear strengthening of steel plates using small-diameter CFRP strands}, volume={184}, ISSN={["1879-1085"]}, DOI={10.1016/j.compstruct.2017.09.094}, abstractNote={This paper presents the results of a comprehensive research program, including experimental and analytical studies, to examine the use of small-diameter CFRP strands for shear strengthening of steel structures and bridges. The experimental program examined the effectiveness of the proposed strengthening system to increase the shear capacity of steel plates subjected to pure shear stresses using a unique test set up. A nonlinear finite element analysis (FEA), calibrated the experimental results, was used to study parameters which were not included in the experiments. Research findings indicated that the proposed system is effective for shear strengthening of steel structures and eliminated the typical debonding failure commonly observed by CFRP laminates.}, journal={COMPOSITE STRUCTURES}, author={Kazem, Hamid and Rizkalla, Sami and Kobayashi, Akira}, year={2018}, month={Jan}, pages={78–91} }
 @article{kazem_guaderrama_selim_rizkalla_kobayashi_2016, title={Strengthening of steel plates subjected to uniaxial compression using small-diameter CFRP strands}, volume={111}, ISSN={["1879-0526"]}, DOI={10.1016/j.conbuildmat.2016.02.028}, abstractNote={This paper presents the results of a study that was carried out to investigate the use of small-diameter CFRP strands for strengthening steel plates subjected to uniaxial compression. This study is part of a comprehensive research program to evaluate the use of the small-diameter CFRP strands for shear strengthening of steel girders. The research in this paper was undertaken to examine the bond characteristics of the proposed material which is expected to eliminate the debonding failure observed for CFRP laminates strengthening system and to resist the compressive stresses induced in high shear zones. The small-diameter CFRP strands are stitched together with a gap between the strands to allow each strand to be completely covered by the adhesive material. The effectiveness of the strengthening system was investigated by varying various parameters believed to affect the overall behavior including the slenderness ratio of the steel plates as well as mechanical properties and reinforcement ratios of the CFRP strands. Strengthened plates exhibited higher buckling capacity in comparison to similar plates without CFRP strands. In addition, the small-diameter CFRP strands did not show any signs of debonding at large lateral deformation associated with elastic buckling.}, journal={CONSTRUCTION AND BUILDING MATERIALS}, author={Kazem, Hamid and Guaderrama, Lucas and Selim, Hatem and Rizkalla, Sami and Kobayashi, Akira}, year={2016}, month={May}, pages={223–236} }
 @article{kazem_bunn_seliem_rizkalla_gleich_2015, title={Durability and long term behavior of FRP/foam shear transfer mechanism for concrete sandwich panels}, volume={98}, ISSN={["1879-0526"]}, DOI={10.1016/j.conbuildmat.2015.08.105}, abstractNote={This paper presents an experimental program to evaluate the effect of sustained loading and outdoor exposure on the shear strength of precast concrete sandwich panels connected with FRP grid/rigid foam insulation as shear transfer mechanism. CFRP and GFRP grids were considered in this study along with EPS and XPS foam. The experimental program is comprised of three different studies with a total of 26 test panels using different combinations of FRP grid and foam insulation.}, journal={CONSTRUCTION AND BUILDING MATERIALS}, author={Kazem, Hamid and Bunn, William G. and Seliem, Hatem M. and Rizkalla, Sami H. and Gleich, Harry}, year={2015}, month={Nov}, pages={722–734} }
 @article{tabrizi_kazem_rizkalla_kobayashi_2015, title={New small-diameter CFRP material for flexural strengthening of steel bridge girders}, volume={95}, ISSN={["1879-0526"]}, DOI={10.1016/j.conbuildmat.2015.07.109}, abstractNote={This paper presents the research findings of an experimental program undertaken to examine the effectiveness of using small-diameter CFRP strands to increase the flexural capacity of steel beams and bridge girders. The experimental program included scaled steel-concrete composite beams, strengthened with these small-diameter strands. The CFRP strands were stitched together with a gap between the strands to allow the adhesive to penetrate and cover the entire perimeter of each strand. Results showed that the proposed system eliminated failure due to de-bonding of the strengthening materials and significantly increased the flexural capacity and stiffness of steel beams.}, journal={CONSTRUCTION AND BUILDING MATERIALS}, author={Tabrizi, Salar and Kazem, Hamid and Rizkalla, Sami and Kobayashi, Akira}, year={2015}, month={Oct}, pages={748–756} }