_1676733870 20230218185430000 CMV Verlag khoffman@cmv-verlag.com Dr. Morteza Jamshidi Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 28 2022 4 4 The role of advanced crisis management in providing relief during an earthquake using the location of vulnerable areas based on the risk matrix (case study: Lahijan city) Sahebeh Kheirkhah Ghorbani In general, crisis management means purposefully pushing the progress of affairs to a controllable routine and expecting things to return to the pre-crisis conditions as soon as possible. In short, crisis management is all actions related to prevention and risk management, organization and management of resources needed in response to crisis. Crisis management is an applied science that, through systematic observation of crises and their analysis, seeks to find tools that can be used to prevent the occurrence of crises or, in case of occurrence, in terms of reducing the effects of the crisis, necessary preparation and rapid relief. and took action to improve the situation. The main purpose of this research is modern crisis management in the probability of an earthquake based on risk matrix by locating vulnerable areas in Lahijan city using AHP, TOPSIS and SWOT analysis. 12 25 2022 33 40 https://creativecommons.org/licenses/by-nc-nd/4.0 10.52547/JCER.4.4.33 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/71 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/71/77 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/71/77 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 28 2022 4 4 Parametric study of two-layer corrugated steel shear wall under lateral load Saeid Ostai Steel shear walls have always been used in the construction and improvement of many structures due to their advantages such as high strength and stiffness, ductility and excellent energy absorption. In the meantime, corrugated steel shear walls have been proposed due to postponing the elastic buckling of the plate and increasing ductility and energy absorption. Corrugated steel shear walls can be used in both single and double layers. Due to the fact that so far, limited research has been conducted about double corrugated steel shear walls, therefore, in this research, the hysteresis behavior of double and single layer corrugated steel shear walls has been analyzed parametrically using the finite element method and using ABAQUS software. Thus, after validating a experimental sample, a two-layer corrugated steel shear wall with one bay-one story with conventional angles of 30, 45 and 60 degrees was investigated in ABAQUS software under cyclic loading. The results of this research showed that the hysteresis curve of double and single layer corrugated steel shear walls is stable. Also, the resistance and energy absorption of double corrugated steel shear walls is higher than single layer corrugated wall. Also, the resistance of corrugated steel shear walls with single and double layers is lower than that of flat steel shear walls. Also, increasing the corrugation angle of the plate has led to an increase in resistance and energy absorption. In addition, behavior factor and ductility of flat steel shear walls are higher than single-layer and double corrugated walls. Nevertheless, the over- strength factor of the studied samples is almost equal to each other. 12 25 2022 51 59 https://creativecommons.org/licenses/by-nc-nd/4.0 10.52547/JCER.4.4.51 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/70 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/70/73 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/70/73 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 28 2022 4 4 Experimental Study of Mechanical Properties of Geopolymer Concrete as Green Concrete with a Sustainable Development Approach in the Construction Industry, Under High Temperature Mohammadhossein Mansourghanaei Morteza Biklaryan Alireza Mardookhpour Today, the use of processed mineral materials in concrete to improve mechanical properties and durability has opened a wide field of vision for researchers in the structural sciences. On the other hand, preserving the environment by reducing the toxic gas of carbon dioxide caused by cement production is one of the concerns of scientists. In this regard, minerals containing abundant aluminosilicate particles and active alkali solution (AAS) replaced ordinary cement in concrete and led to the production of geopolymer concrete (GPC). The composition and reactivity of these materials produce a strong adhesive material that in combination with other concrete components, causes the final strength of GPC. High temperatures weaken the concrete against loads by damaging the structure of hydrated gels in concrete. GPC has better fire resistance than OPCC due to its density in its microstructure. In the current study, Granulated Blast Furnace Slag (GBFS)-based GPC was used with 0-2% polyolefin fibers (POFs) and 0-8% Nano silica (NS) to improve its structure. After curing the specimens under dry conditions at a temperature of 60 °C in an oven, they were subjected to Compressive strength, Modulus of elasticity and Weight Loss tests to evaluate their mechanical properties. all tests were performed at 90 days of age under ambient temperature (20 ℃) and high temperature (500 ℃). The addition of NS enhanced the whole properties of the GBFS-based GPC. Addition of up to 8% NS to the GPC composition at 20% temperature improved the modulus of elasticity test results by 13.42% and the compressive strength up to 21.94% by 11.58%. Addition of up to 2% of POFs to the GPC composition resulted in an improvement, modulus of elasticity of 07.05% and a decrease in compressive strength of up to 22.49%. Apply the lowest (0.061%) and highest (0.12%) weight loss percentage of concrete samples under 500% heat, belonging to scheme 4 (including GPC containing 8% NS) and scheme 6 (including GPC containing 2% POFs) Came. In the following, by conducting the Slag, Scanning Electron Microscope (SEM) analysis, a microstructure investigation was carried out on the concrete samples. In addition to their overlapping with each other, the results indicate the GPC superiority over the regular concrete. Besides, it demonstrated the positive influence of NS addition on the concert microstructure. 12 25 2022 1 11 https://creativecommons.org/licenses/by-nc-nd/4.0 10.52547/JCER.4.4.1 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/68 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/68/68 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/68/68 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 28 2022 4 4 Comparative study of numerical methods used in prediction of post-crack behavior of waffle slabs Alireza Sheikhnasiri One effective way to reduce dead and earthquake loads is to use waffle slabs. The use of waffle slabs leads to smaller sections. There are various methods for predicting the behavior of slabs, the most important of which is fracture mechanics. Considering the variety of geometry of waffle slabs, it is important to investigate the formation and growth of cracks in them. The current research aims to analyze the post-crack behavior of waffle slabs under common loading conditions using the finite element method by using numerical modeling to analyze cracks in reinforced concrete members. by comparing the obtained results with the laboratory sample, the optimal numerical model for predicting the behavior of the hollow slab was determined. The waffle slab sample was modeled with two types of distributed and concentrated loading conditions and two types of simple and fixed support conditions. The models were modeled by two methods of concrete damage plasticity and smeared cracked concrete by Abaqus software. Various parameters of these samples, including the load-displacement diagram, the load coincident with the formation of cracks, the displacement in the middle of the slab opening, and the pattern of the formation and propagation of cracks, etc., were discussed and investigated. To validate and control the modeling process, the laboratory results of the research of Nithyambigai G et al. in 2021 have been used. The outcomes of this study showed; a relatively good correspondence between the two methods of Concrete damage plasticity and the concrete smeared crack model, but due to the definition of failure in the Concrete damage plasticity method, more accurate results can be obtained. 12 25 2022 12 19 https://creativecommons.org/licenses/by-nc-nd/4.0 10.52547/JCER.4.4.12 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/66 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/66/69 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/66/69 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 28 2022 4 4 Investigating the compressive and tensile strength of concrete containing recycled aggregate with polypropylene fibers Donya Khazraie Hossein Razzaghi In this research, recycled concrete aggregates were used instead of natural aggregates in concrete, and then the recycled concrete was reinforced with polypropylene fibers.The purpose of this study is to first investigate the effect of replacing recycled aggregates with natural aggregates on the mechanical resistance of concrete and then to investigate the effect of adding polypropylene and micro silica fibers on concrete containing natural and recycled aggregates in two water-to-cement ratios of 0.4 and 0.55. The results of this research show that by replacing recycled aggregates with natural aggregates, the compressive and tensile strengths of concrete have decreased significantly. Also, the results show that the addition of polypropylene fibers with a weight ratio of 1.5% had a significant effect in compensating the reduction of compressive and tensile strengths in recycled concrete. It should be mentioned that the samples containing microsilica and polypropylene fibers in all mixing designs (natural and recycled aggregates) had higher resistance values ​​(tension and pressure) than the samples without microsilica. Also, concrete samples with a water-cement ratio of 0.4 had higher compressive strengths than concrete samples with a water-cement ratio of 0.55. 12 25 2022 20 32 https://creativecommons.org/licenses/by-nc-nd/4.0 10.52547/JCER.4.4.20 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/7 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/7/75 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/7/75 Journal of Civil Engineering Researchers jcer 2538-516X 2538-516X 12 28 2022 4 4 Analytical and Experimental Study of Load-bearing columns Made of Lightweight Concrete Ghasem Azizi Mohsen Abzan In recent years, studies have been started for the use of light-grained concrete in conventional reinforced concrete structures, it is expected that the use of light-grained concrete without having a negative effect on the use of the structure will reduce the costs in construction and reduce the structural mass. As a result, the earthquake load will be reduced. In this research, concrete with an approximate compressive strength of 18.24 megapascals and an approximate specific weight of 1800 kg/m3 was obtained by using Lika grain style. In order to evaluate the structural behavior of lightweight concrete, 5 concrete columns were built in the laboratory and were subjected to axial load and the results related to these columns were presented, and then a suitable model for these columns was presented by Abaqus finite element software and analytical studies It was done on the relevant results, which are in good agreement with the laboratory results. The agreement of the results obtained from the modeling with the laboratory results is a proof of the accuracy of the built model.  © 2017 Journals-Researchers. All rights reserved 12 25 2022 41 50 https://creativecommons.org/licenses/by-nc-nd/4.0 10.52547/JCER.4.4.41 https://www.journals-researchers.com/ojs/index.php/jcer/article/view/1 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/1/78 https://www.journals-researchers.com/ojs/index.php/jcer/article/download/1/78