_1676737492 20230218195452000 CMV Verlag khoffman@cmv-verlag.com Dr. Morteza Jamshidi Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 02 25 2022 4 1 Hadi Darvishi In addition to the conventional lateral load resistance system such as different brace system, using of another kind of system that called Steel Plate Shear Wall (SPSW) is extending. Most of the SPSW that used in the construction of the building structure are stiffened by other elements that perpendicular to the frame surface to prevent their buckling. Recent studies show that the performances of this kind of lateral load resistance systems will be improve if the infill plate buckled before the yielding of the surrounding frame. So using of too thick plate is developed that accrued some construction problem and decrease the economic advantage of them. Using of the perforated steel plate shear wall is an applied strategy to remove this problem and lead to the buckle of the infill plate. Using of the perforated steel plate incorporate some confusedness base on the lacking of the code. In this paper 21 number of perforated steel plate shear walls analyzed under cyclic loading by using of the ABAQUS. An appropriate perforated pattern is suggested by study on the hysteresis diagrams. The results show that using of bad pattern reduces the ability of energy absorption and suddenly remove the stability of the SPSW. Otherwise, using of the proper pattern improve the cyclic performance of the perforated steel plate shear wall camper to the other system. 02 25 2022 55 66 https://creativecommons.org/licenses/by-nc-nd/4.0 10.52547/JCER.4.1.55 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/52 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/52/51 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/52/51 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 02 25 2022 4 1 Mohammadreza Noori Shirazi This paper presents a new rectified square steel jacket for retrofitting of poorly confined reinforced concrete columnsin flexural plastic hinge regions. All of the analyses was carried out based on finite elements procedure. Having verifiedthe FE modeling, a deficient RC column designed according to pre-1971 codes was considered and eleven specimen withvarious detail of retrofitting were investigated. Effects of increasing at thickness of plate stiffeners, geometric shape ofstiffeners and stiffened length of jacketed column have been studied. The results obtained from the parametric studyindicated effectiveness of rectified jacket and allow a series of guidelines to be established. 02 25 2022 39 54 https://creativecommons.org/licenses/by-nc-nd/4.0 10.52547/JCER.4.1.39 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/51 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/51/50 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/51/50 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 02 25 2022 4 1 Farhad Nabizadeh Helical piles have been extensively used as a deep foundation system for small to large load ranges and are thus suitable for various applications. Therefore, a concern over qualifying and quantifying their axial bearing capacities and performance characteristics seems to be warranted. This paper discusses design considerations, installation procedures, and results of full-scale field load tests. In this study, axial static loading tests on single, double, and triple helix helical piles under grouted and un-grouted conditions have been conducted. The field study has been performed on silty-clay soil, to investigate the behavior of helical piles. Also, the results of the piles load tests were interpreted using six methods presented in literature to predict the ultimate load capacity (Qu) for each pile. Results showed that in the silty-clay soil, grouted and un-grouted helical piles had a similar performance while grouted piles showed greater axial compressive strength. According to various limit load methods evaluation, it was concluded that the values for two methods of Chin, Decourt were close to the site values. 02 25 2022 29 38 https://creativecommons.org/licenses/by-nc-nd/4.0 10.52547/JCER.4.1.29 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/50 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/50/49 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/50/49 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 02 25 2022 4 1 Lobat Hosseinzadeh Reinforced concrete columns to steel beam connections are recently considered as structural system. This system takes the advantages of both through optimally combining metal and concrete structural elements. There are two connections through beam and through column connections. This study first reviewed the literature; then, the authors modeled a sample connection experimentally carried out in a laboratory by Cheng Chih and Cheng Tung Chen in 2005 by ABAQUS finite element software and investigated seismic performance of RCS connections under back/forward and monotonic loadings. Once the finite element model was validated, a parametric study (studying web steel panel thickness at the joint, studying coating thickness, etc.) was conducted; and finally, a modified model was proposed following connection results were compared showing a more stable and desired behavior in addition to the increased capacity of the connections. The result showed that the use of a through-plate with shear keys in the joint zone will increase the strength of the joint and the formation of a plastic joint outside the joint and will greatly improve the joint behavior. So that the contribution of concrete in the shear capacity of this area has increased, which was 73% for the modified model of Cheng and Chen. Also the use of a through-plate for RCS joints converts the forces transmitted from the beam to in-plane stresses and by shear keys, through two shear and support mechanisms, these forces are transferred to the concrete of the joint area and in consequence, these stresses are transferred to the concrete column. 02 25 2022 21 28 https://creativecommons.org/licenses/by-nc-nd/4.0 10.52547/JCER.4.1.21 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/49 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/49/48 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/49/48 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 02 25 2022 4 1 Ghasem Azizi In recent years, the use of lightweight concrete in the world has grown exponentially. The reason is the lightening of the buildingand as a result the reduction of dead load and seismic force on the structures as well as better performance in terms of thermalinsulation and energy saving. Therefore, it is necessary to study the potentials of using lightweight concrete in the constructionindustry. In this article, which is the result of analytical and experimental results about a special type of lightweight aggregatecalled Leica, the aim is to first achieve a lightweight concrete mixing design that has the necessary conditions as lightweightstructural concrete. In this paper, during laboratory research, using Leica concrete grain style with an approximate compressivestrength of 20 MPa and a specific gravity of approximately 1800 kg / m3 was obtained. Secondly, we investigated the structuralbehavior of concrete beams made with Leica lightweight aggregate experimentally and numerically. For this purpose, the first 5concrete beams were made and examined in the laboratory, and finally, using ABAQUS finite element software, a suitable modelwas found to model such beams, which is in good coordination with the laboratory results. The compatibility of the resultsobtained from the modeling with the laboratory results is proof of the accuracy of the constructed model. 02 25 2022 12 20 https://creativecommons.org/licenses/by-nc-nd/4.0 10.52547/JCER.4.1.12 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/48 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/48/47 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/48/47 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 02 25 2022 4 1 Javad Pourali Ehsan Omranian Gholamreza Abdollahzadeh The aftershocks may weaken or collapse structures that were previously damaged under the main earthquake and have not yetbeen repaired. In this paper, the seismic performance of an 8-story Steel moment frame structures designed in four types ofsoil is evaluated under the seismic sequence of earthquake and aftershock. The results showed that the seismic performance ofthe studied frame under the influence of severe aftershocks can be significantly different from the main earthquake modealone. For example, in type 1 soil, aftershocks can increase the structure displacement by more than 50% compared to themain earthquake mode alone. It was also found that most aftershocks cause a significant increase in the durable displacementof the roof and in a small number of cases it also reduces it. In addition, the impact of aftershocks on the building damaged bythe main earthquake will be much greater than in the case in which the structure under the main earthquake has not sufferedmuch damage. 02 25 2022 1 11 https://creativecommons.org/licenses/by-nc-nd/4.0 10.52547/JCER.4.1.1 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/47 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/47/46 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/47/46