Amirkabir University of Technology Amirkabir Journal of Civil Engineering 2588-297X 56 6 2024 08 22 Study of the Effect of Porcelain Sheathing Direction on the Lateral Resistance of Cold-Formed Steel Shear Wall under Constant Gravity Loading by Experiment Study of the Effect of Porcelain Sheathing Direction on the Lateral Resistance of Cold-Formed Steel Shear Wall under Constant Gravity Loading by Experiment 653 676 5436 10.22060/ceej.2024.22451.7984 FA Saeedreza Sowlat-tafti Department of Civil Engineering, Taft Branch, Islamic Azad University, Yazd, Iran. Mohammadreza Javaheri-tafti Civil Eng. Deprt., Yazd Branch, Islamic Azad Univ., Yazd, Iran. 0000-0001-6860-0705 Hamidreza Ronagh School of Civil Engineering, The University of Queensland, Brisbane, Australia 0000-0001-7826-5760 Journal Article 2023 06 18 The lateral behavior of cold-formed steel shear wall is dependent on several factors including the type of sheathing used. However, only a limited number of sheathing types have been studied using specific installation method. In this study, due to the high demands of builders to use local materials for sheathing light steel frames, which, in addition to being abundant and easy to obtain, can also create a variety of designs such as stone or brick to match the facade of existent parts of the building, two full-scale samples of cold-formed steel shear walls in dimensions of 1.2×2.4 meters sheathed by porcelain ceramic with different configurations have tested under combined constant gravity loading and standard cyclic lateral loading regime. After calculation of ductility and response factors by using of specimens tests results, The seismic effect of the sheathing rectangular pieces orient, which can be installed in either horizontal or vertical strips, is investigated. The study also evaluates the failure modes of the systems. The results of the tests show that porcelain sheathing pieces installation in vertical strips instead of horizontal strips causes a decrease of approximately 50% in Energy Dissipation and 18% in ultimate lateral resistance without effect on seismic response modification factor, R. The lateral behavior of cold-formed steel shear wall is dependent on several factors including the type of sheathing used. However, only a limited number of sheathing types have been studied using specific installation method. In this study, due to the high demands of builders to use local materials for sheathing light steel frames, which, in addition to being abundant and easy to obtain, can also create a variety of designs such as stone or brick to match the facade of existent parts of the building, two full-scale samples of cold-formed steel shear walls in dimensions of 1.2×2.4 meters sheathed by porcelain ceramic with different configurations have tested under combined constant gravity loading and standard cyclic lateral loading regime. After calculation of ductility and response factors by using of specimens tests results, The seismic effect of the sheathing rectangular pieces orient, which can be installed in either horizontal or vertical strips, is investigated. The study also evaluates the failure modes of the systems. The results of the tests show that porcelain sheathing pieces installation in vertical strips instead of horizontal strips causes a decrease of approximately 50% in Energy Dissipation and 18% in ultimate lateral resistance without effect on seismic response modification factor, R.

https://ceej.aut.ac.ir/article_5436_cf8c9be2a4508a24ae92c9d3d379131d.pdf

Amirkabir University of Technology Amirkabir Journal of Civil Engineering 2588-297X 56 6 2024 08 22 Seismic Performance of Building Frames with Buckling Resistance Braces Under Far and Near Field with and without Pulse Earthquakes Seismic Performance of Building Frames with Buckling Resistance Braces Under Far and Near Field with and without Pulse Earthquakes 677 704 5437 10.22060/ceej.2024.22550.7993 FA Abdol Ghaium Dehvari Assistant Professor Department of Civil Engineering, University of Velayat, Iranshahr, Sistan and Baluchestan, Iran 0000-0001-6131-3818 Mohsen Khazaei Assistant Professor, Department of Civil Engineering, Faculty of Engineering Science, Quchan University of Technology, Quchan, Iran Journal Article 2023 07 13 Buckling Resistance braces are known as elements which resistant to axial loads in tension and compression. The present study is focused on the seismic behavior of low to medium height of braced building frame, which equipped with non-buckling braces under far and near fault with and without pulse earthquakes. In this research, building frames with pinned beam-to-column connections in 4 and 8 stories have been studied. Incremental dynamic analysis has been performed for 14 earthquake records from all three domains. The results obtained from the incremental dynamic analysis for the studied frames under the selected earthquake records with the conditions and characteristics affected by the distance from the earthquake site, has shown the vulnerability of 4 and 8-story frames with pinned beam-to-column joints against ground movements in all three areas distance from location of the fault and for the damage parameter of inter story drift ratio. Also, the results have shown that the bracing members are the most vulnerable members of this frame. The median acceleration that obtained to a 4-story structure and for the performance levels of immediate occupancy, life safety and collapse threshold to meet the functional conditions of the inter story drift ratio as damage parameter in far-field earthquakes are 0. 30 g, 0. 85 g and 1. 05 g, and 0. 40 g, 0. 75 g, and 0. 95 g were obtained for the near field with pulse, and 0. 30 g, 0. 80 g, and 1. 00 g for the near field without pulse, respectively. Buckling Resistance braces are known as elements which resistant to axial loads in tension and compression. The present study is focused on the seismic behavior of low to medium height of braced building frame, which equipped with non-buckling braces under far and near fault with and without pulse earthquakes. In this research, building frames with pinned beam-to-column connections in 4 and 8 stories have been studied. Incremental dynamic analysis has been performed for 14 earthquake records from all three domains. The results obtained from the incremental dynamic analysis for the studied frames under the selected earthquake records with the conditions and characteristics affected by the distance from the earthquake site, has shown the vulnerability of 4 and 8-story frames with pinned beam-to-column joints against ground movements in all three areas distance from location of the fault and for the damage parameter of inter story drift ratio. Also, the results have shown that the bracing members are the most vulnerable members of this frame. The median acceleration that obtained to a 4-story structure and for the performance levels of immediate occupancy, life safety and collapse threshold to meet the functional conditions of the inter story drift ratio as damage parameter in far-field earthquakes are 0. 30 g, 0. 85 g and 1. 05 g, and 0. 40 g, 0. 75 g, and 0. 95 g were obtained for the near field with pulse, and 0. 30 g, 0. 80 g, and 1. 00 g for the near field without pulse, respectively.

https://ceej.aut.ac.ir/article_5437_0a3b6f64f0523984e51323fe53b8c504.pdf

Amirkabir University of Technology Amirkabir Journal of Civil Engineering 2588-297X 56 6 2024 08 22 The Use of Copper Tailing of Mineral Processing Plant in the Preparation of Concrete in order to Prevent Environmental Pollution The Use of Copper Tailing of Mineral Processing Plant in the Preparation of Concrete in order to Prevent Environmental Pollution 705 728 5438 10.22060/ceej.2024.22706.8033 FA Yusuf Dorzadeh University of Sistan and Baluchestan Aliakbar Daya University of Sistan and Baluchestan Marzieh Hosseini Nasab University of Sistan and Baluchestan Journal Article 2023 09 28 Copper tailing is the by-product of copper processing plants, and due to their large volume and physical and chemical characteristics, they bring many environmental and economic problems. The recent research examines the effect of using mineral processing tailings of copper as a substitute for cement on the mechanical properties and durability of concrete. For this purpose, five mixing plans with different percentages of copper tailings from the Chehel-Koreh mine were used in concrete production. This tail contains Si, Fe, Mg, and Al. 105 samples including 75 cubic samples with dimensions of 10×10×10 cm and 30 cylindrical samples with dimensions of 15×30 cm were prepared. The results showed that using 5% copper tail improved the compressive strength compared to the control sample. If the copper tail increased to 10%, a decrease in the compressive strength was observed, and despite this decrease, the compressive strength was still higher than the control sample. By using copper tailings, there was a slight decrease in tensile strength. Electrical resistance and water absorption tests at the age of 28 days showed that using copper tail causes a slight decrease in electrical resistance and water absorption. In addition, adding 5 to 10 percent copper tailings instead of cement will reduce concrete production costs and energy consumption with less cement consumption, reduce damage to the environment with less cement production, and optimal use of copper tailings. Therefore, copper tailings can be used as a suitable alternative for partial replacement of cement in concrete. Copper tailing is the by-product of copper processing plants, and due to their large volume and physical and chemical characteristics, they bring many environmental and economic problems. The recent research examines the effect of using mineral processing tailings of copper as a substitute for cement on the mechanical properties and durability of concrete. For this purpose, five mixing plans with different percentages of copper tailings from the Chehel-Koreh mine were used in concrete production. This tail contains Si, Fe, Mg, and Al. 105 samples including 75 cubic samples with dimensions of 10×10×10 cm and 30 cylindrical samples with dimensions of 15×30 cm were prepared. The results showed that using 5% copper tail improved the compressive strength compared to the control sample. If the copper tail increased to 10%, a decrease in the compressive strength was observed, and despite this decrease, the compressive strength was still higher than the control sample. By using copper tailings, there was a slight decrease in tensile strength. Electrical resistance and water absorption tests at the age of 28 days showed that using copper tail causes a slight decrease in electrical resistance and water absorption. In addition, adding 5 to 10 percent copper tailings instead of cement will reduce concrete production costs and energy consumption with less cement consumption, reduce damage to the environment with less cement production, and optimal use of copper tailings. Therefore, copper tailings can be used as a suitable alternative for partial replacement of cement in concrete.

https://ceej.aut.ac.ir/article_5438_479b4864e55e12e0fb411eadb115c095.pdf

Amirkabir University of Technology Amirkabir Journal of Civil Engineering 2588-297X 56 6 2024 08 22 Thermodynamic and kinetic study of LC3 cement during sulfate attack Thermodynamic and kinetic study of LC3 cement during sulfate attack 729 748 5452 10.22060/ceej.2024.22088.7901 FA Sama Karkhaneh Shahid Rajaee Teacher Training University Amir Tarighat Shahid RajaeeTeacher Training University 0000-0003-0475-8129 Saeed Ghaffarpour Jahromi Department of Geotechnical Engineering and Water Engineering, Shahid Rajaee Teacher Training University 0000-0002-3033-7195 Journal Article 2023 01 11 Concrete is the most common materials for the construction. One of the most important issues about the concrete construction design is the service life of structure. The concrete sulfate attack as the well-known concrete deterioration problem reduces the service life of concrete structures. In this study, LC3 cement (limestone calcined clay cement) as an eco-friendly cement due to the reduction of clincker demand, and also as an effective solution for the increasing the cement durability in sulfate-rich environments has been studied. A thermodynamic simulation has been conducted to evaluate the performance of LC3 cement (limestone calcined clay cement) against the sulfate attack, with the consideration of the time parameter, using a thermodynamic software. The simulation results are compared with experimental and modeling results to the confirmation of present model accuracy. The comparison of result shows the suitable conformity. In this study, different kinetics level for ettringite and gypsum (as the main products of sulfate attack) formation has been introduced. Analyzing kinetics diagrams show that high Calcined Clay/ Calcined Clay + Limestone ratio leads to reduction of ettringite and gypsum formation amount and formation rate during the sulfate attack, however Calcined Clay/ Calcined Clay + Limestone ratio of 0.6 could be consider as the optimal ratio because of better kinetics performance. Concrete is the most common materials for the construction. One of the most important issues about the concrete construction design is the service life of structure. The concrete sulfate attack as the well-known concrete deterioration problem reduces the service life of concrete structures. In this study, LC3 cement (limestone calcined clay cement) as an eco-friendly cement due to the reduction of clincker demand, and also as an effective solution for the increasing the cement durability in sulfate-rich environments has been studied. A thermodynamic simulation has been conducted to evaluate the performance of LC3 cement (limestone calcined clay cement) against the sulfate attack, with the consideration of the time parameter, using a thermodynamic software. The simulation results are compared with experimental and modeling results to the confirmation of present model accuracy. The comparison of result shows the suitable conformity. In this study, different kinetics level for ettringite and gypsum (as the main products of sulfate attack) formation has been introduced. Analyzing kinetics diagrams show that high Calcined Clay/ Calcined Clay + Limestone ratio leads to reduction of ettringite and gypsum formation amount and formation rate during the sulfate attack, however Calcined Clay/ Calcined Clay + Limestone ratio of 0.6 could be consider as the optimal ratio because of better kinetics performance.

https://ceej.aut.ac.ir/article_5452_febefe1cc5c87748ea02036dbe9e3d67.pdf

Amirkabir University of Technology Amirkabir Journal of Civil Engineering 2588-297X 56 6 2024 08 22 Comparing the Behavior of Dense Sandy Soils Inside and Outside the Shear Band in the Direct Shear Test Using the Two-dimensional Discrete Element Method Comparing the Behavior of Dense Sandy Soils Inside and Outside the Shear Band in the Direct Shear Test Using the Two-dimensional Discrete Element Method 749 774 5453 10.22060/ceej.2024.22244.7938 FA Ahmadreza Javid Yazd University Mohammad Hazeghian a department of Civil Engineering, Yazd university, Yazd, iran 0000-0002-0841-0122 Mohammad Abdoli Department of Civil Engineering, Yazd University, Yazd, Iran Journal Article 2023 03 04 Shear banding is one of the most significant behavioral characteristics of granular soils, which is actually the result of the localization of deformations under loads applied to the soil sample. Many studies have been conducted on the phenomenon of shear band formation. However, the comparison of the behavior of soil inside and outside the shear band has received less attention. The purpose of this study is to compare the behavior of soil inside and outside the shear band in the direct shear test at macro and micro scales using the two-dimensional discrete element method. To achieve this, the micro-material parameters were first calibrated through the comparison of simulation and experimental results. Then a parametric study was conducted by performing 9 direct shear tests with different vertical stresses on three soil samples with different relative densities. During the tests, quantities such as shear stress, porosity, particle rotation, coordination number, and interparticle plastic energy were measured both inside and outside the shear band. The results of the present study showed that the particle rotations at the end of the test inside the shear band were 5 to 17 times higher than those outside the shear band. Furthermore, the results showed that the dissipated energies at the end of the test inside the shear band were 12 to 96 times larger than those outside the shear band. Moreover, it was found that the coordination numbers at the end of the test inside the shear band were on average 3-19% lesser than those outside it. Shear banding is one of the most significant behavioral characteristics of granular soils, which is actually the result of the localization of deformations under loads applied to the soil sample. Many studies have been conducted on the phenomenon of shear band formation. However, the comparison of the behavior of soil inside and outside the shear band has received less attention. The purpose of this study is to compare the behavior of soil inside and outside the shear band in the direct shear test at macro and micro scales using the two-dimensional discrete element method. To achieve this, the micro-material parameters were first calibrated through the comparison of simulation and experimental results. Then a parametric study was conducted by performing 9 direct shear tests with different vertical stresses on three soil samples with different relative densities. During the tests, quantities such as shear stress, porosity, particle rotation, coordination number, and interparticle plastic energy were measured both inside and outside the shear band. The results of the present study showed that the particle rotations at the end of the test inside the shear band were 5 to 17 times higher than those outside the shear band. Furthermore, the results showed that the dissipated energies at the end of the test inside the shear band were 12 to 96 times larger than those outside the shear band. Moreover, it was found that the coordination numbers at the end of the test inside the shear band were on average 3-19% lesser than those outside it.

https://ceej.aut.ac.ir/article_5453_8ae5780d22688d976ebce9d8fb3db81c.pdf

Amirkabir University of Technology Amirkabir Journal of Civil Engineering 2588-297X 56 6 2024 08 22 Investigation of Excess Pore Water Pressure in Cone Penetration Test in Saturated Clayey Soils under Undrained Condition Investigation of Excess Pore Water Pressure in Cone Penetration Test in Saturated Clayey Soils under Undrained Condition 775 800 5454 10.22060/ceej.2024.22402.7975 FA Mahdiyeh Fakhimi Akmal department of civil engineering at sharif university of technology, tehran, iran Mahammad Mehdi Ahmadi department of civil engineering at sharif university of technology, tehran, iran Journal Article 2023 05 27 The widespread use of the cone penetration test in geotechnical engineering, due to its quick identification of soil layers and properties, has led to the development of various analytical methods for interpreting this test. Monitoring excess pore water pressure during the piezocone penetration test can be crucial for assessing the properties and engineering parameters of clayey soils. The initial stresses in the ground and the coefficient of lateral earth pressure at rest, K0, are important parameters needed for the design and analysis of various geotechnical problems such as piles, and slope stabilities. Due to the limited research on clayey soils, the significance of understanding their behavior, and the limitations of laboratory experiments, this study investigates soil behavior via numerical modeling of cone penetration tests in saturated clay with undrained conditions. In this study, the effect of the coefficient of lateral earth pressure and initial effective vertical stresses on pore water pressure has been investigated. Additionally, the correlations between excess pore water pressures at points u2 and u1, as well as u2 and u3, have been outlined. A modified Cam-Clay constitutive model was employed in all numerical analyses using FLAC2D software. The validation of proposed relationships was also addressed using the database of field tests available in the literature provided by different researchers. The obtained results indicated that as each parameter of lateral pressure coefficient and vertical effective stress increased, the excess pore water pressure also increased at all three locations where pore water pressure is measured. The widespread use of the cone penetration test in geotechnical engineering, due to its quick identification of soil layers and properties, has led to the development of various analytical methods for interpreting this test. Monitoring excess pore water pressure during the piezocone penetration test can be crucial for assessing the properties and engineering parameters of clayey soils. The initial stresses in the ground and the coefficient of lateral earth pressure at rest, K0, are important parameters needed for the design and analysis of various geotechnical problems such as piles, and slope stabilities. Due to the limited research on clayey soils, the significance of understanding their behavior, and the limitations of laboratory experiments, this study investigates soil behavior via numerical modeling of cone penetration tests in saturated clay with undrained conditions. In this study, the effect of the coefficient of lateral earth pressure and initial effective vertical stresses on pore water pressure has been investigated. Additionally, the correlations between excess pore water pressures at points u2 and u1, as well as u2 and u3, have been outlined. A modified Cam-Clay constitutive model was employed in all numerical analyses using FLAC2D software. The validation of proposed relationships was also addressed using the database of field tests available in the literature provided by different researchers. The obtained results indicated that as each parameter of lateral pressure coefficient and vertical effective stress increased, the excess pore water pressure also increased at all three locations where pore water pressure is measured.

https://ceej.aut.ac.ir/article_5454_107030ca685076c0ed5e054e2c3ed940.pdf