University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 05 21 Microstructural Examination of Effects of Organic Crude Oil Pollutant on the Geotechnical Properties and Geo-Environmental of Marl Soil of Mishan Formation Microstructural Examination of Effects of Organic Crude Oil Pollutant on the Geotechnical Properties and Geo-Environmental of Marl Soil of Mishan Formation 1 12 16612 10.22034/ceej.2023.55305.2224 FA Mohammad Amiri University of Hormozgan, Faculty of Engineering, Bandar Abbas, Iran Behzad Kalantari University of Hormozgan, Faculty of Engineering, Bandar Abbas, Iran Fatemeh Basereh University of Hormozgan, Faculty of Engineering, Bandar Abbas, Iran Journal Article 2023 02 11 The expansion of oil-dependent industries has caused a growing rate of oil extraction and increasing oil- and its derivatives-contaminated water and soil. The impacts and damages caused by oil pollution on human resources, water, and the environment have been very complicated. Oil and its derivates leakages into the soil can change its physical and mechanical properties. Oil-contaminated lands are thought of as the main challenge to the environment. Fuel and oil-reserve sites are common oil leak sites that may penetrate the soil. However, most Bandar Abbas refineries are situated on marl soil beds. Marl is composed of clay, and calcium carbonates of varying degrees of 20-65%, which, having been hardened, are converted into marl soil, thus becoming physically stiff and impermeable. Marl soil has high stiffness and shear strength under dry conditions, as these properties experience lower rates under wet conditions. The volatile behavior of the marl soil in water and organic pollutants makes it problematic when used in geotechnical projects. Thus, the present research takes a microstructural approach to investigate the geotechnical properties and environmental geotechnics of the marl soil contaminated with varying degrees of crude oil. The expansion of oil-dependent industries has caused a growing rate of oil extraction and increasing oil- and its derivatives-contaminated water and soil. The impacts and damages caused by oil pollution on human resources, water, and the environment have been very complicated. Oil and its derivates leakages into the soil can change its physical and mechanical properties. Oil-contaminated lands are thought of as the main challenge to the environment. Fuel and oil-reserve sites are common oil leak sites that may penetrate the soil. However, most Bandar Abbas refineries are situated on marl soil beds. Marl is composed of clay, and calcium carbonates of varying degrees of 20-65%, which, having been hardened, are converted into marl soil, thus becoming physically stiff and impermeable. Marl soil has high stiffness and shear strength under dry conditions, as these properties experience lower rates under wet conditions. The volatile behavior of the marl soil in water and organic pollutants makes it problematic when used in geotechnical projects. Thus, the present research takes a microstructural approach to investigate the geotechnical properties and environmental geotechnics of the marl soil contaminated with varying degrees of crude oil.

https://ceej.tabrizu.ac.ir/article_16612_1360dde9bfbda5664fd75d0130e959b7.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 Experimental Evaluation of Application of Demolition Waste Material to Improve the Interface Parameters of Geotextile and Sand Experimental Evaluation of Application of Demolition Waste Material to Improve the Interface Parameters of Geotextile and Sand 13 21 15452 10.22034/jcee.2022.50385.2119 FA Mehdi Hosseinzadeh Sotoubadi Faculty of Engineering, University of Mohaghegh Ardabili, Ardabil, Iran Ahad Ouria Faculty of Engineering, University of Mohaghegh Ardabili, Ardabil, Iran Amin Gholizad Faculty of Engineering, University of Mohaghegh Ardabili, Ardabil, Iran Journal Article 2022 02 13 Mechanical properties of mechanically stabilized earth structures depend on the mechanical parameters of the fill material, tensile strength of reinforcement elements, and the interface properties of the geosynthetic and the fill material (Ouria and Mahmoudi, 2018). Optimal design of reinforced earth systems demands for a pullout capacity of reinforcements proportional to their tensile strength (Ouria et al., 2019) (Ouria et al., 2021) (Ouria et al., 2022). That is why the utilization of high strength reinforcements in reinforced earth structures has not been developed extensively. Anchorage of high strength reinforcements requires long anchorage length of mechanically anchored ends. On the other hand, rapid development of societies requires renewal of several structures and substructures (Ouria et al., 2020)(Ouria and Heidarly, 2021)(Ouria and Sadeghpour, 2022). The replacement of existing substructures requires new materials and also produces demolition waste material in large quantities (Vieira and Pereira, 2015). The huge rate of the production of demolition waste material in the recent years raised concerns about the harmful impacts of these material in the environment (Savadkoohi and Reisi, 2020). Recycling of these waste material and their utilization in new projects could be proper step in response to the raised concerns. In this study the applicability of demolition waste material in the reinforced soil structures was investigated in the laboratory. Mechanical properties of mechanically stabilized earth structures depend on the mechanical parameters of the fill material, tensile strength of reinforcement elements, and the interface properties of the geosynthetic and the fill material (Ouria and Mahmoudi, 2018). Optimal design of reinforced earth systems demands for a pullout capacity of reinforcements proportional to their tensile strength (Ouria et al., 2019) (Ouria et al., 2021) (Ouria et al., 2022). That is why the utilization of high strength reinforcements in reinforced earth structures has not been developed extensively. Anchorage of high strength reinforcements requires long anchorage length of mechanically anchored ends. On the other hand, rapid development of societies requires renewal of several structures and substructures (Ouria et al., 2020)(Ouria and Heidarly, 2021)(Ouria and Sadeghpour, 2022). The replacement of existing substructures requires new materials and also produces demolition waste material in large quantities (Vieira and Pereira, 2015). The huge rate of the production of demolition waste material in the recent years raised concerns about the harmful impacts of these material in the environment (Savadkoohi and Reisi, 2020). Recycling of these waste material and their utilization in new projects could be proper step in response to the raised concerns. In this study the applicability of demolition waste material in the reinforced soil structures was investigated in the laboratory.

https://ceej.tabrizu.ac.ir/article_15452_fb4daf2843aa0e7b0773bacd9cec118d.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 New Formulation for Dynamic Analysis of Nonlinear Time-History of Vibrations of Structures under Earthquake Loading New Formulation for Dynamic Analysis of Nonlinear Time-History of Vibrations of Structures under Earthquake Loading 22 35 16408 10.22034/ceej.2023.54564.2209 FA Mohammad Reza Hanafi Bachelor of Civil Engineering, Department of Civil Engineering, University of Bonab, Bonab, Iran Mehdi Babaei Assistant professor, Department of Civil Engineering, University of Bonab, Bonab, Iran Peyman Narjabadifam Assistant professor, Department of Civil Engineering, University of Bonab, Bonab, Iran Journal Article 2022 12 25 A fast and efficient numerical scheme is presented for time-history analysis of single-degree-of-freedom (SDOF) structural systems undergoing seismic excitation (Chopra, 2003). The new method is called Newton-Cotes-4P-θ Method. It uses the most known 4-point Newton-Cotes quadrature in its body to solve the vibration equation. Nonlinear analysis is covered as well as linear analysis. Any arbitrary external loadings of type force or seismic signals are welcome. The significant advantages of the new formulation are its great simplicity, running speed, and appropriate precision level compared with its counterparts such as Duhamel integral and Newmark-β methods. The accuracy level of the Newton-Cotes-4P-θ is close to the semi-analytical method of Duhamel integration and its speed is similar to the Newmark-β algorithm. Notably, against the nonlinear Newmark-β method, the new method does not require a standalone procedure to handle nonlinear analysis; instead, it simply triggers iteration of the same computation used in its first processing round. Moreover, the Newmark-β method loses its performance dealing with stiff and near-conservative () systems; however, the Newton-Cotes-4P-θ method does not loos its accuracy and keeps its well-performed analysis in this case. Numerical results reveal the superiority of the Newton-Cotes- 4P-θ method against its counterparts such as the Duhamel integral, Newmark-β, and Wilson-θ methods (Babaei et al., 2021; Babaei et al., 2022; Babaei et al., 2023). A fast and efficient numerical scheme is presented for time-history analysis of single-degree-of-freedom (SDOF) structural systems undergoing seismic excitation (Chopra, 2003). The new method is called Newton-Cotes-4P-θ Method. It uses the most known 4-point Newton-Cotes quadrature in its body to solve the vibration equation. Nonlinear analysis is covered as well as linear analysis. Any arbitrary external loadings of type force or seismic signals are welcome. The significant advantages of the new formulation are its great simplicity, running speed, and appropriate precision level compared with its counterparts such as Duhamel integral and Newmark-β methods. The accuracy level of the Newton-Cotes-4P-θ is close to the semi-analytical method of Duhamel integration and its speed is similar to the Newmark-β algorithm. Notably, against the nonlinear Newmark-β method, the new method does not require a standalone procedure to handle nonlinear analysis; instead, it simply triggers iteration of the same computation used in its first processing round. Moreover, the Newmark-β method loses its performance dealing with stiff and near-conservative () systems; however, the Newton-Cotes-4P-θ method does not loos its accuracy and keeps its well-performed analysis in this case. Numerical results reveal the superiority of the Newton-Cotes- 4P-θ method against its counterparts such as the Duhamel integral, Newmark-β, and Wilson-θ methods (Babaei et al., 2021; Babaei et al., 2022; Babaei et al., 2023).

https://ceej.tabrizu.ac.ir/article_16408_b06aa94399041cacfbcba072130a215d.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 Temperature Optimization of Small Smart Residential Buildings Using Fuzzy Inference Rules Considering User Comfort Temperature Optimization of Small Smart Residential Buildings Using Fuzzy Inference Rules Considering User Comfort 36 45 14308 10.22034/jcee.2022.49552.2107 FA Yazdan Daneshvar Department of Civil Engineering, Qazvin Branch, Islamic Azad University, Qazvin, Iran Majid Sabzehparvar Department of Industrial Engineering, Faculty of Engineering, Karaj Branch, Islamic Azad University, Karaj, Iran Seyed Amir Hossein Hashemi Department of Civil Engineering, Qazvin Branch, Islamic Azad University, Qazvin, Iran Journal Article 2021 12 22 The present article is a model for the optimal management of energy consumption of smart residential buildings by considering the emotional characteristics to ensure the comfort of residents. In order to smarten the indoor temperature based on emotional components (clothing, outdoor temperature, age, body mass index (BMI1), humidity and number of residents) by expert system and questionnaire, temperature has been determined as a basis. Mogles et al, in an article entitled Designing Behavioral Interactions of Energy Changes for a Computational Model, investigated creating a structure to fit various types of models and using the simulation model as a tool for evaluation, which affects consumption decisions. According to the results, the presented model can predict the energy saving behavior much better than the existing stochastic models and correctly estimate the effect of the accepted technologies. Also, the analytical model can become a decision-making system in accordance with the change of energy behavior (Mogles et al., 2018). The present article is a model for the optimal management of energy consumption of smart residential buildings by considering the emotional characteristics to ensure the comfort of residents. In order to smarten the indoor temperature based on emotional components (clothing, outdoor temperature, age, body mass index (BMI1), humidity and number of residents) by expert system and questionnaire, temperature has been determined as a basis. Mogles et al, in an article entitled Designing Behavioral Interactions of Energy Changes for a Computational Model, investigated creating a structure to fit various types of models and using the simulation model as a tool for evaluation, which affects consumption decisions. According to the results, the presented model can predict the energy saving behavior much better than the existing stochastic models and correctly estimate the effect of the accepted technologies. Also, the analytical model can become a decision-making system in accordance with the change of energy behavior (Mogles et al., 2018).

https://ceej.tabrizu.ac.ir/article_14308_41260e7d7400849a4654151f505839be.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 A Plaster Based on Gypsum and Investigation of Its Thermal Insulation Properties A Plaster Based on Gypsum and Investigation of Its Thermal Insulation Properties 46 55 16288 10.22034/ceej.2023.53351.2180 FA Ehsan Moazzen Department of Civil Engineering, Hakim Sabzevari University, Sabzevar 9617976487, Iran Rasoul Shadnia Department of Civil Engineering, Hakim Sabzevari University, Sabzevar 9617976487, Iran Journal Article 2022 09 07 Considering the increasing consumption and decreasing of energy on the planet, creating new methods to reduce energy consumption by humans is one of the necessary priorities for continuation and survival. In civil engineering, many researchers are trying to reduce energy consumption by conducting laboratory and theoretical research on building materials (Ajouguim et al., 2021; Singh et al., 2022) especially linings and plaster trodes (Touil et al., 2022). In the present paper, an attempt has been made to present a plaster based on a combination of new and old materials, which can be a step in the development of the thermal insulation industry, both in terms of quality and cost. The purpose of this research is to reach a plaster with characteristics similar to thatch, but with the elimination of defects such as cracking due to continuous cold and heat, erosion due to rain and moisture, and continuous drying. In the production of this plaster, which is based on gypsum, in the first step, some investigations and tests were carried out on different materials, including traditional thatch mixtures. In the end, the final product was obtained by adding materials such as gypsum, clay, wood powder, glass wool and some nano materials with the aim of producing a plaster with a thermal conductivity coefficient lower than the existing ones. This plaster will be used for plastering inside the building like gypsum plaster and has advantages such as not having a thermal bridge on the entire surface, not having seams and cracks, as well as not destroying and falling over time due to its high adhesion. This research has tried to increase the quality of thermal insulation in the construction industry and by taking the idea from the behavior of straw, to produce a much more optimal coating, both in terms of efficiency, availability and saving energy consumption, as well as in terms of costs. Considering the increasing consumption and decreasing of energy on the planet, creating new methods to reduce energy consumption by humans is one of the necessary priorities for continuation and survival. In civil engineering, many researchers are trying to reduce energy consumption by conducting laboratory and theoretical research on building materials (Ajouguim et al., 2021; Singh et al., 2022) especially linings and plaster trodes (Touil et al., 2022). In the present paper, an attempt has been made to present a plaster based on a combination of new and old materials, which can be a step in the development of the thermal insulation industry, both in terms of quality and cost. The purpose of this research is to reach a plaster with characteristics similar to thatch, but with the elimination of defects such as cracking due to continuous cold and heat, erosion due to rain and moisture, and continuous drying. In the production of this plaster, which is based on gypsum, in the first step, some investigations and tests were carried out on different materials, including traditional thatch mixtures. In the end, the final product was obtained by adding materials such as gypsum, clay, wood powder, glass wool and some nano materials with the aim of producing a plaster with a thermal conductivity coefficient lower than the existing ones. This plaster will be used for plastering inside the building like gypsum plaster and has advantages such as not having a thermal bridge on the entire surface, not having seams and cracks, as well as not destroying and falling over time due to its high adhesion. This research has tried to increase the quality of thermal insulation in the construction industry and by taking the idea from the behavior of straw, to produce a much more optimal coating, both in terms of efficiency, availability and saving energy consumption, as well as in terms of costs.

https://ceej.tabrizu.ac.ir/article_16288_74eab82ff1f0f66d137f7a1436e2e6d1.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 Numerical Investigation of Block Form Effect in Amount of Dissipated Energy of Baffled Apron Spillway Drop by Flow3D Numerical Investigation of Block Form Effect in Amount of Dissipated Energy of Baffled Apron Spillway Drop by Flow3D 56 62 18056 10.22034/jcee.2020.13438.1349 FA Davood Sedaghat Shayegan Faculty of Civil Engineering, Islamic Azad University, Roudehen branch, Teharan, Iran Mohammad Reza Roosta Faculty of Civil Engineering, Islamic Azad University, Roudehen branch, Teharan, Iran Journal Article 2016 05 05 Baffled aprons or Chutes have been in use on irrigation projects for many years. The fact that many of these structures have been built and have performed satisfactorily indicates that they are practical and that in many cases they are an economical answer to the problem of dissipating energy. Baffled chutes are used to dissipate the energy in the flow at a drop and are most often used on channel waste ways or drops. During the past 2 decades, heuristic and metaheuristic optimization techniques have emerged as a promising solution, offering several benefits and possibilities. (Saberi et al., 2021; Sedaghat et al., 2019). Baffled aprons or Chutes have been in use on irrigation projects for many years. The fact that many of these structures have been built and have performed satisfactorily indicates that they are practical and that in many cases they are an economical answer to the problem of dissipating energy. Baffled chutes are used to dissipate the energy in the flow at a drop and are most often used on channel waste ways or drops. During the past 2 decades, heuristic and metaheuristic optimization techniques have emerged as a promising solution, offering several benefits and possibilities. (Saberi et al., 2021; Sedaghat et al., 2019).

https://ceej.tabrizu.ac.ir/article_18056_480268fd4b4024e979c23710e71f11a7.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 Investigating the Seismic Performance of Masonry Infills with Opening and Non-Opening by Considering the Interaction of Behavior in Plane and Out of the Plane and Providing the Reduction Factor of Effective Stiffness and Ultimate Strength Investigating the Seismic Performance of Masonry Infills with Opening and Non-Opening by Considering the Interaction of Behavior in Plane and Out of the Plane and Providing the Reduction Factor of Effective Stiffness and Ultimate Strength 56 83 16127 10.22034/ceej.2023.53972.2194 FA Delaram Ostad Faculty of Civil Engineering, Shahrood University of Technology, Shahrood, Iran Jalil Shafaei Faculty of Civil Engineering, Shahrood University of Technology Journal Article 2022 10 31 Masonry infills are an unavoidable member of any building. The presence of openings in a masonry infill alters its behaviour and reduces the load strength and stiffness of the infilled frame. Considering the reality of the masonry infill, the capacity of masonry infill is defined in two separate modes of in-plane (IP) force and out-plane (OOP) force (Asteris et al., 2017). In this paper, the main goal is to investigate masonry infills with different window and door openings with different dimensions and locations under three types of loading, which are: 1-Out-of-plane Loading of masonry infill under different accelerations. 2-Out-of-plane loading after in-plane loading at relative displacements (drift) of 0.5%, 1%, 2%, and 3% and check for Out-of-plane damage. 3-In-plane loading up to 6% relative displacement (drift) after out-of-plane loading and checking for in-plane damage. The numerical models are generated in finite element ABAQUS soft. Nonlinear pushover analyses have been conducted for each of the three loading. At the end, reduction factors of effective stiffness and ultimate strength are suggested. By using these suggested reduction factors, the design engineer can model the interaction effects in-plane and out-of-plane using the compression diagonal struts method. The average reduction of the infill stiffness was calculated by considering the interaction in-plane and out-of-plane 30%. Masonry infills are an unavoidable member of any building. The presence of openings in a masonry infill alters its behaviour and reduces the load strength and stiffness of the infilled frame. Considering the reality of the masonry infill, the capacity of masonry infill is defined in two separate modes of in-plane (IP) force and out-plane (OOP) force (Asteris et al., 2017). In this paper, the main goal is to investigate masonry infills with different window and door openings with different dimensions and locations under three types of loading, which are: 1-Out-of-plane Loading of masonry infill under different accelerations. 2-Out-of-plane loading after in-plane loading at relative displacements (drift) of 0.5%, 1%, 2%, and 3% and check for Out-of-plane damage. 3-In-plane loading up to 6% relative displacement (drift) after out-of-plane loading and checking for in-plane damage. The numerical models are generated in finite element ABAQUS soft. Nonlinear pushover analyses have been conducted for each of the three loading. At the end, reduction factors of effective stiffness and ultimate strength are suggested. By using these suggested reduction factors, the design engineer can model the interaction effects in-plane and out-of-plane using the compression diagonal struts method. The average reduction of the infill stiffness was calculated by considering the interaction in-plane and out-of-plane 30%.

https://ceej.tabrizu.ac.ir/article_16127_598c97f7bbbac6477a4a8a1eba994cec.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 Evaluation and Compression of Burst Pressure for High/Mid-Grade Corroded Pipelines Using Finite Element Model Evaluation and Compression of Burst Pressure for High/Mid-Grade Corroded Pipelines Using Finite Element Model 84 98 12823 10.22034/jcee.2021.37486.1888 FA Mohhamad Ali Sharaki Nader Department of Civil Engineering, University of Zabol, Iran Behrooz Keshtegar Department of Civil Engineering, University of Zabol, Iran Mahmoud Reza Hossieni Tabatabaie Department of Civil Engineering, University of Zabol, Iran Journal Article 2019 12 24 The applications of steel pipelines for oil and gas transportation have grown over the past three decades. Due to the biological, service life performance, economical issue and human safety, it is important to keep a safe performance for oil/gas pipeline and to evaluate their serviceability under uncertainties including environmental issues (i.e. corroded defects) and applied loads (i.e. internal pressure). The accurate estimation of structural performance as load capacity-based burst pressure of steel pipes under corroded defects can be provided a robust design in service life. Therefore, predicting the residual strength of pipelines with corrosion defects is an important problem in these kinds of industrial structures. A one of oriented design relation of corroded burst pressure models is the ASME B31G which was presented by the American national standard Institution (ANSI). In the term of PCORRC criterion, Stephens and leis (2000) presented a mathematical model based on exponential nonlinear function using experimental results for low and moderate-strength steels. Generally, the shape of corrosion was considered as a rectangular form using DNV RP F101 (2004) for low and moderate-strength steels. Zhu and Leis (2005) applied the material hardening behavior in the mathematical model for prediction of corroded burst pressure. The presented model is extracted from X80 steel grade while it may be not covered the vast categories of steel pipes. (Ma et al., 2013) applied the Ramberg-Osgood relationship for material in finite element models (FEM) of steel pipes under single corrosion. However, they did not discuss the different yield strains of materials. The FEM have been used for computing the strength capacity of corroded pies by (Mechri et al., 2016), (Hieu et al., 2017) and (Shuai et al., 2017), but the Ramberg-Osgood nonlinear martial model has not considered with different yield strains. The applications of steel pipelines for oil and gas transportation have grown over the past three decades. Due to the biological, service life performance, economical issue and human safety, it is important to keep a safe performance for oil/gas pipeline and to evaluate their serviceability under uncertainties including environmental issues (i.e. corroded defects) and applied loads (i.e. internal pressure). The accurate estimation of structural performance as load capacity-based burst pressure of steel pipes under corroded defects can be provided a robust design in service life. Therefore, predicting the residual strength of pipelines with corrosion defects is an important problem in these kinds of industrial structures. A one of oriented design relation of corroded burst pressure models is the ASME B31G which was presented by the American national standard Institution (ANSI). In the term of PCORRC criterion, Stephens and leis (2000) presented a mathematical model based on exponential nonlinear function using experimental results for low and moderate-strength steels. Generally, the shape of corrosion was considered as a rectangular form using DNV RP F101 (2004) for low and moderate-strength steels. Zhu and Leis (2005) applied the material hardening behavior in the mathematical model for prediction of corroded burst pressure. The presented model is extracted from X80 steel grade while it may be not covered the vast categories of steel pipes. (Ma et al., 2013) applied the Ramberg-Osgood relationship for material in finite element models (FEM) of steel pipes under single corrosion. However, they did not discuss the different yield strains of materials. The FEM have been used for computing the strength capacity of corroded pies by (Mechri et al., 2016), (Hieu et al., 2017) and (Shuai et al., 2017), but the Ramberg-Osgood nonlinear martial model has not considered with different yield strains.

https://ceej.tabrizu.ac.ir/article_12823_ba079b7a4f91466ff4d8f8bd6d038d30.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 Investigating the Effect of Saturated Sand Layer Thickness on the Performance of Deep Soil Mixing Columns and Gravel Columns in Reducing Risks Caused By Liquefaction Investigating the Effect of Saturated Sand Layer Thickness on the Performance of Deep Soil Mixing Columns and Gravel Columns in Reducing Risks Caused By Liquefaction 99 114 16387 10.22034/ceej.2023.53598.2186 FA Gholi Asadzadeh Khoshemehr Faculty of Civil Engineering, Urmia University, Urmia, Iran Hadi Bahadori Faculty of Civil Engineering, Urmia University, Urmia, Iran Journal Article 2022 09 27 In the present paper, the results of a series of seismic experiments in a 1g environment on a structure located over liquefiable ground with different thicknesses reinforced with GD and DSM techniques were presented. The dynamic response of the reinforced ground system was investigated based on the parameters of settlement, excess pore water pressure ratio, maximum acceleration, behavior of stress-strain of reinforced soil. The time history of the input acceleration was applied harmonically with an acceleration range of 0.2g and at frequencies of 1, 2, and 3 Hz. results of experimental investigations show that the thickness of the liquefiable layer and the frequency of the input motion have a significant impact on the effectiveness of the improvement method and all responses. In the present paper, the results of a series of seismic experiments in a 1g environment on a structure located over liquefiable ground with different thicknesses reinforced with GD and DSM techniques were presented. The dynamic response of the reinforced ground system was investigated based on the parameters of settlement, excess pore water pressure ratio, maximum acceleration, behavior of stress-strain of reinforced soil. The time history of the input acceleration was applied harmonically with an acceleration range of 0.2g and at frequencies of 1, 2, and 3 Hz. results of experimental investigations show that the thickness of the liquefiable layer and the frequency of the input motion have a significant impact on the effectiveness of the improvement method and all responses.

https://ceej.tabrizu.ac.ir/article_16387_1e399e8fe9e6b90402a350fc42862f16.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 Derivation of Huff Curves for the Four Stations in Great Karun River in Khuzestan Province S Derivation of Huff Curves for the Four Stations in Great Karun River in Khuzestan Province S 115 130 15419 10.22034/jcee.2022.28050.1678 FA Yagob Dinpashoh Faculty of Agriculture, University of Tabriz, Tabriz 5166614766, Iran Esmatolsadat Alavi Faculty of Agriculture, University of Tabriz, Tabriz 5166614766, Iran Journal Article 2018 06 25 The first step in scientific water resources management is good understanding of the temporal precipitation pattern. One of the main tools in understanding the rainfall pattern is plotting the Huff curves. This is true especially in arid and semi-arid regions encountered with water shortages. These help decision makers in understanding temporal characteristics of rainfall, which in turn can help efficient management of water resources. Temporal distribution of rainfalls interested by many investigators in the field of hydrology such as Yen and chow (1980), Loukas and Quick (1994), Todisco (2014), Huff (1967 & 1990) and many others. Furthermore, illustration of Huff curves for different rain gauge stations performed by many researchers such as Azli and Rao (2010), Awadallah and Younan (2012), Yazdi et al. (2016), Shokri-koochak et el. (2011), and many others. In a recently published work by Ewea et al. (2016) the Huff curves were plotted for the city of Makkah Al-Mukkaramah in Saudi Arabia. Based on our best knowledge, there is no comprehensive scientific work carried out on illustration of Huff curves in Great Karun River basin, located in south west of Iran. Therefore, the main objective of this study is illustration of Huff curves and analysis of storm pattern during the rainfall occurrence in the four selected stations, including the Dez dam, Abdul-Khan, Gotvand and Ahwaz. These selected stations are located in Karun River basin, Khuzestan province, Iran. The first step in scientific water resources management is good understanding of the temporal precipitation pattern. One of the main tools in understanding the rainfall pattern is plotting the Huff curves. This is true especially in arid and semi-arid regions encountered with water shortages. These help decision makers in understanding temporal characteristics of rainfall, which in turn can help efficient management of water resources. Temporal distribution of rainfalls interested by many investigators in the field of hydrology such as Yen and chow (1980), Loukas and Quick (1994), Todisco (2014), Huff (1967 & 1990) and many others. Furthermore, illustration of Huff curves for different rain gauge stations performed by many researchers such as Azli and Rao (2010), Awadallah and Younan (2012), Yazdi et al. (2016), Shokri-koochak et el. (2011), and many others. In a recently published work by Ewea et al. (2016) the Huff curves were plotted for the city of Makkah Al-Mukkaramah in Saudi Arabia. Based on our best knowledge, there is no comprehensive scientific work carried out on illustration of Huff curves in Great Karun River basin, located in south west of Iran. Therefore, the main objective of this study is illustration of Huff curves and analysis of storm pattern during the rainfall occurrence in the four selected stations, including the Dez dam, Abdul-Khan, Gotvand and Ahwaz. These selected stations are located in Karun River basin, Khuzestan province, Iran.

https://ceej.tabrizu.ac.ir/article_15419_743ad4b1c4ea5fc0f81b7bf19e20d31a.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 Investigation of the Effect of Chips Orientation on the Shear Strength of Sand-Rubber Chips Mixture Investigation of the Effect of Chips Orientation on the Shear Strength of Sand-Rubber Chips Mixture 131 141 16118 10.22034/ceej.2023.53947.2196 FA Moslem Alikhani Faculty of Civil Engineering, University of Sirjan, Sirjan, Iran Mohsen Asadi Faculty of Civil Engineering, University of Sirjan, Sirjan, Iran Journal Article 2022 11 08 Mixing the tire shred and tire chips, derived from scrape tires, to sand is an option to use scrape tires. Based on the ASTM (2017) there is no environmental risk for embankments made from tire derived aggregates. In the past three decades several experimental investigation have been reported on the sand-rubber chips mixture behavior (Edil et al., 1990; Zornberg et al., 2004; Neaz Sheikh et al., 2012). Since the ration of area to thickness of chips is large, they tend to become horizontal when being mixed with the sand and subsequently would not be parallel to the probable failure surface of a foundation or a trench. This point has been investigated limitedly in the literature (Foose et al., 1996; Gotteland et al., 2005). In the present paper, an innovative mold is used to compact the sand-rubber chips mixture where the chips are inclined. The experimental program was carried out to investigate the effect of rubber chips orientation in the sand-rubber chips mixture. Mixing the tire shred and tire chips, derived from scrape tires, to sand is an option to use scrape tires. Based on the ASTM (2017) there is no environmental risk for embankments made from tire derived aggregates. In the past three decades several experimental investigation have been reported on the sand-rubber chips mixture behavior (Edil et al., 1990; Zornberg et al., 2004; Neaz Sheikh et al., 2012). Since the ration of area to thickness of chips is large, they tend to become horizontal when being mixed with the sand and subsequently would not be parallel to the probable failure surface of a foundation or a trench. This point has been investigated limitedly in the literature (Foose et al., 1996; Gotteland et al., 2005). In the present paper, an innovative mold is used to compact the sand-rubber chips mixture where the chips are inclined. The experimental program was carried out to investigate the effect of rubber chips orientation in the sand-rubber chips mixture.

https://ceej.tabrizu.ac.ir/article_16118_27a68844421a30f89132e26d3b173ef1.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 05 21 Investigating the Performance of Kstar and GPR Algorithms in Modeling RDI Meteorological Drought Index (Case Study: East of Urmia Lake Basin) Investigating the Performance of Kstar and GPR Algorithms in Modeling RDI Meteorological Drought Index (Case Study: East of Urmia Lake Basin) 142 151 16313 10.22034/ceej.2023.55292.2225 FA Marzie Sadeghian Agkandy Department of Water Science and Engineering, Urmia University, Iran Hossein Rezaie Department of Water Science and Engineering, Urmia University, Iran Keivan Khalili Department of Water Science and Engineering, Urmia University, Iran Farshad Ahmadie Department of Hydrology and Water Resources, Shahid Chamran University of Ahvaz, Iran Journal Article 2023 02 13 Drought is a severe hydrological event that can cause serious problems in human life. In this context, it can have adverse effects on water supply and quality, public health, agricultural productivity, land degradation, desertification, famine, etc. (Madadgar and Moradkhani, 2014; Li et al., 2020). In a general classification, drought events are classified into four different categories, meteorological, hydrological, agricultural and socio-economic droughts (Wilhite and Glantz, 1985; Khadr, 2016). Some of the well-known and common meteorological drought indices in drought monitoring include Palmer Drought Severity Index (PDSI), Drought Identification Index (RDI), Standardized Precipitation Index (SPI) and Standard Precipitation Evapotranspiration Index. Considering the significant role of evaporation and transpiration in the water balance, it is necessary to consider its effect when studying drought in a particular region. Based on this, RDI, which includes both precipitation and evaporation and transpiration, can be considered as a reliable indicator for drought monitoring (Moeinifar et al., 1400). According to importance of drought as a natural phenomenon in hydrological and meteorological studies, its monitoring and forecasting with a suitable approach can be important. The main role of Drought prediction in risk management, reducing the effects of drought on existing water resources and their optimal use, the possibility of rational decision-making by decision makers to minimize the damages caused by drought, as well as planning and managing resource projects. It has water. (Khadr et al., 2016; Madrigal et al., 2018; Beyaztas and Yaseen, 2019). Among the models worked till date, single Kstar and GPR models are the newest models for drought prediction. Drought is a severe hydrological event that can cause serious problems in human life. In this context, it can have adverse effects on water supply and quality, public health, agricultural productivity, land degradation, desertification, famine, etc. (Madadgar and Moradkhani, 2014; Li et al., 2020). In a general classification, drought events are classified into four different categories, meteorological, hydrological, agricultural and socio-economic droughts (Wilhite and Glantz, 1985; Khadr, 2016). Some of the well-known and common meteorological drought indices in drought monitoring include Palmer Drought Severity Index (PDSI), Drought Identification Index (RDI), Standardized Precipitation Index (SPI) and Standard Precipitation Evapotranspiration Index. Considering the significant role of evaporation and transpiration in the water balance, it is necessary to consider its effect when studying drought in a particular region. Based on this, RDI, which includes both precipitation and evaporation and transpiration, can be considered as a reliable indicator for drought monitoring (Moeinifar et al., 1400). According to importance of drought as a natural phenomenon in hydrological and meteorological studies, its monitoring and forecasting with a suitable approach can be important. The main role of Drought prediction in risk management, reducing the effects of drought on existing water resources and their optimal use, the possibility of rational decision-making by decision makers to minimize the damages caused by drought, as well as planning and managing resource projects. It has water. (Khadr et al., 2016; Madrigal et al., 2018; Beyaztas and Yaseen, 2019). Among the models worked till date, single Kstar and GPR models are the newest models for drought prediction.

https://ceej.tabrizu.ac.ir/article_16313_0dd10d4cce60a9d4ad9aa8e483723634.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 Parametric Study and Formulation of Scfs in Axially Loaded Multi-Planar Tubular XT-Joints Reinforced with Internal Ring Stiffeners Parametric Study and Formulation of Scfs in Axially Loaded Multi-Planar Tubular XT-Joints Reinforced with Internal Ring Stiffeners 152 167 18055 10.22034/jcee.2021.42052.1968 FA Hamid Ahmadi National Centre for Maritime Engineering and Hydrodynamics, University of Tasmania, TAS 7248, Australia and Centre for Future Materials, University of Southern Queensland, QLD 4350, Australia Ahmad Kouhi Faculty of Civil Engineering, University of Tabriz , Iran Journal Article 2020 09 29 Many tubular joints commonly found in offshore jacket structures are multi-planar. Investigating the effect of loaded out-of-plane braces on the values of the stress concentration factor (SCF) in offshore tubular joints has been the objective of numerous research works. However, due to the diversity of joint types and loading conditions, several quite important cases still exist that have not been studied thoroughly. Among them are internally ring-stiffened multi-planar XT-joints subjected to axial loading. In the present research, data extracted from the stress analysis of 81 finite element (FE) models, verified using experimental test results, was used to study the effects of geometrical parameters on the chord-side SCFs in multi-planar tubular XT-joints reinforced with internal ring stiffeners subjected to two types of axial loading. Parametric FE study was followed by a set of the nonlinear regression analyses to develop four new SCF parametric equations for the fatigue analysis and design of axially loaded multi-planar XT-joints reinforced with internal ring stiffeners. Many tubular joints commonly found in offshore jacket structures are multi-planar. Investigating the effect of loaded out-of-plane braces on the values of the stress concentration factor (SCF) in offshore tubular joints has been the objective of numerous research works. However, due to the diversity of joint types and loading conditions, several quite important cases still exist that have not been studied thoroughly. Among them are internally ring-stiffened multi-planar XT-joints subjected to axial loading. In the present research, data extracted from the stress analysis of 81 finite element (FE) models, verified using experimental test results, was used to study the effects of geometrical parameters on the chord-side SCFs in multi-planar tubular XT-joints reinforced with internal ring stiffeners subjected to two types of axial loading. Parametric FE study was followed by a set of the nonlinear regression analyses to develop four new SCF parametric equations for the fatigue analysis and design of axially loaded multi-planar XT-joints reinforced with internal ring stiffeners.

https://ceej.tabrizu.ac.ir/article_18055_605e3683ab9fbd618ac6ad304cfc1a78.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 An Optimized Stiffened Sandwich Panel for Impact-Protective Doors An Optimized Stiffened Sandwich Panel for Impact-Protective Doors 168 179 16239 10.22034/ceej.2023.55815.2237 FA Maede Zamani Department of Civil Engineering, Urmia University, Urmia, Iran Habib Saaed Monir Department of Civil Engineering, Urmia University, Urmia, Iran Journal Article 2023 03 12 Protective steel doors are widely used in buildings due to their high resistance against the impact loads. However, its heavy weight has been always considered as a major drawback for these doors. In this paper, a new optimized stiffened impact-protective steel door incorporating sandwich panel with aluminum foam core (OSSA) is examined. This door consists of two face sheets, main and secondary stiffeners, and aluminum foam as the inner core. In order to optimize the door, at first the rigidity and weight functions of the stiffened steel door were extracted. Then an optimal door weighing 42% less than the primary door was obtained. Due to the high energy absorption capacity of the combined foam core and stiffened steel door structure, the use of aluminum foam core in the optimized steel door was proposed. By doing numerical analysis, and depending on the thickness of the face sheet of OSSA, 20 to 32% reduction in the maximum displacement was observed. The results also showed that, with 67% increase in the peak overpressure, OSSA has kept almost the same maximum displacement as that of the steel door without an aluminum foam. In other words, by using aluminum foam core in the optimized stiffened door, the door will resist 67% more impact load. Protective steel doors are widely used in buildings due to their high resistance against the impact loads. However, its heavy weight has been always considered as a major drawback for these doors. In this paper, a new optimized stiffened impact-protective steel door incorporating sandwich panel with aluminum foam core (OSSA) is examined. This door consists of two face sheets, main and secondary stiffeners, and aluminum foam as the inner core. In order to optimize the door, at first the rigidity and weight functions of the stiffened steel door were extracted. Then an optimal door weighing 42% less than the primary door was obtained. Due to the high energy absorption capacity of the combined foam core and stiffened steel door structure, the use of aluminum foam core in the optimized steel door was proposed. By doing numerical analysis, and depending on the thickness of the face sheet of OSSA, 20 to 32% reduction in the maximum displacement was observed. The results also showed that, with 67% increase in the peak overpressure, OSSA has kept almost the same maximum displacement as that of the steel door without an aluminum foam. In other words, by using aluminum foam core in the optimized stiffened door, the door will resist 67% more impact load.

https://ceej.tabrizu.ac.ir/article_16239_d8c7aa3679877607eb1960860d358903.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 06 19 Influence of different pushover loading patterns on nonlinear response of concrete bridges with piers of unequal height Influence of different pushover loading patterns on nonlinear response of concrete bridges with piers of unequal height 180 189 16497 10.22034/ceej.2023.45804.2030 FA Gezel Galdiani Civil Engineering- Babol Noshirvani University of Tevhnology Hamidreza Tavakoli Faculty of Civil Engineering, Babol Noshirvani University of Technology, Babol, Iran Alireza Mirza Gholtabar Faculty of Civil Engineering, Babol Noshirvani University of Technology, Babol, Iran Journal Article 2021 05 01 Pushover is a non-linear static process, where a lateral load defined by a different load pattern than before, which represents the inertial forces in a particular earthquake, is defined as increasing uniformly until it reaches the target displacement or destruction. In this analysis, the overall force intensity has changed, but the load pattern remains the same until the end of the analysis, so the results of the Pushover analysis are highly sensitive to the applied load pattern. In the traditional Pushover analysis, uniform distribution, the response is only considered under the influence of the first mode assuming that it does not change, if the constant force distribution cannot be used in the distribution of internal forces due to the yielding of the structure and the changes related to the vibration characteristics, including the increase the participation of higher modes in the response of the structure gives a correct estimate. Therefore, in order to develop and include the effect of higher modes, three new load pattern examples are proposed in the analysis of concrete bridge with continuous straight deck and piers of different height. The pattern of uniformly distributed lateral loads based on the FEMA-273 regulation, the upper band method, the modal spectral composition, and the second method of modal composition of the patterns used here. Based on the results of this research, in short bridges, the modal combination method, and in long bridges, the spectral modal combination method have created the closest estimation of the response parameters among other methods. Pushover is a non-linear static process, where a lateral load defined by a different load pattern than before, which represents the inertial forces in a particular earthquake, is defined as increasing uniformly until it reaches the target displacement or destruction. In this analysis, the overall force intensity has changed, but the load pattern remains the same until the end of the analysis, so the results of the Pushover analysis are highly sensitive to the applied load pattern. In the traditional Pushover analysis, uniform distribution, the response is only considered under the influence of the first mode assuming that it does not change, if the constant force distribution cannot be used in the distribution of internal forces due to the yielding of the structure and the changes related to the vibration characteristics, including the increase the participation of higher modes in the response of the structure gives a correct estimate. Therefore, in order to develop and include the effect of higher modes, three new load pattern examples are proposed in the analysis of concrete bridge with continuous straight deck and piers of different height. The pattern of uniformly distributed lateral loads based on the FEMA-273 regulation, the upper band method, the modal spectral composition, and the second method of modal composition of the patterns used here. Based on the results of this research, in short bridges, the modal combination method, and in long bridges, the spectral modal combination method have created the closest estimation of the response parameters among other methods.

https://ceej.tabrizu.ac.ir/article_16497_9ec80a9e72f25df0270e376b28e4be21.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 06 19 Comparison of Liquid Limit Obtained From Casagrande Cup Method and Cone Penetrometer for Sand and Clay Mixed Soils Comparison of Liquid Limit Obtained From Casagrande Cup Method and Cone Penetrometer for Sand and Clay Mixed Soils 190 200 16270 10.22034/ceej.2023.54157.2200 FA Mahmoud Nikkhah Shahmirzadi Department of Civil Engineering, Semnan Branch, Islamic Azad University, Semnan, Iran Ghasem Arabi 2Department of Civil Engineering, Semnan Branch, Islamic Azad University, Semnan, Iran Minoo Zahra Hafezi 2Department of Civil Engineering, Semnan Branch, Islamic Azad University, Semnan, Iran Journal Article 2022 11 17 The behavior of the cohesive soil depends on many factors. Atterberg limits play an important role in the evaluation and classification of clays. In this paper, the relationship between the Liquid limit of the cone penetrometer methods and Casagrande cup of sand and clay mixed soils has been evaluated. The main purpose of this study is to compare the Liquid limit values obtained from the hard-base Casagrande device with the cone penetration method and to present the relationship between the Liquid limit values obtained from the two methods in terms of the percentage of sand in the mixed soil. The behavior of the cohesive soil depends on many factors. Atterberg limits play an important role in the evaluation and classification of clays. In this paper, the relationship between the Liquid limit of the cone penetrometer methods and Casagrande cup of sand and clay mixed soils has been evaluated. The main purpose of this study is to compare the Liquid limit values obtained from the hard-base Casagrande device with the cone penetration method and to present the relationship between the Liquid limit values obtained from the two methods in terms of the percentage of sand in the mixed soil.

https://ceej.tabrizu.ac.ir/article_16270_b432b2964b9c605ee1961165f843b351.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 Effect of Dimensions and Shape of Clay Core Section of Earth Dams on Reliability Coefficient of Hydraulic Failure Effect of Dimensions and Shape of Clay Core Section of Earth Dams on Reliability Coefficient of Hydraulic Failure 201 210 16388 10.22034/ceej.2023.55246.2221 FA Mostafa Zalnejad Faculty of Civil Engineering, University of Kharazmi, Tehran, Iran Seyed Shahab Emamzadeh Faculty of Civil Engineering, University of Kharazmi, Tehran, Iran Journal Article 2023 02 04 Hydraulic fracturing can occur in the fine-grained core of earthen dams. This phenomenon often occurs during the first water intake of the dam when the water pressure suddenly increases. Hydraulic fracturing in Erath dam has investigated laboratory by many researchers (Jaworski, 1981; Jian, 2022; Patel, 2017). In this research, the aim is to investigate numerically the phenomenon of hydraulic fracture and the effect of the dimensions and shape of the clay core section of the Hajiler Chai Dam (an earthen dam with impermeable clay core) located in East Azarbayjan province on the reliability coefficient of hydraulic fracture. For this purpose, first, using Geo-Studio, the phenomenon of hydraulic fracturing has been investigated in two sections in the middle of the core (A-A) and the upstream side of the core (B-B) of the dam for two types of materials CL and CH. Analyzes have been done in the stages of the end of construction, initial dewatering and steady state seepage, and the stages of dam construction have also been considered in the modeling. Also, the possibility of hydraulic fracture in thicker cores and the bottom of the core was also investigated. Finally, the reliability coefficient of hydraulic failure occurrence has been quantitatively calculated for each of the soils in stages and sections and with different criteria, and the suitable soil has been suggested for use in the dam core. Hydraulic fracturing can occur in the fine-grained core of earthen dams. This phenomenon often occurs during the first water intake of the dam when the water pressure suddenly increases. Hydraulic fracturing in Erath dam has investigated laboratory by many researchers (Jaworski, 1981; Jian, 2022; Patel, 2017). In this research, the aim is to investigate numerically the phenomenon of hydraulic fracture and the effect of the dimensions and shape of the clay core section of the Hajiler Chai Dam (an earthen dam with impermeable clay core) located in East Azarbayjan province on the reliability coefficient of hydraulic fracture. For this purpose, first, using Geo-Studio, the phenomenon of hydraulic fracturing has been investigated in two sections in the middle of the core (A-A) and the upstream side of the core (B-B) of the dam for two types of materials CL and CH. Analyzes have been done in the stages of the end of construction, initial dewatering and steady state seepage, and the stages of dam construction have also been considered in the modeling. Also, the possibility of hydraulic fracture in thicker cores and the bottom of the core was also investigated. Finally, the reliability coefficient of hydraulic failure occurrence has been quantitatively calculated for each of the soils in stages and sections and with different criteria, and the suitable soil has been suggested for use in the dam core.

https://ceej.tabrizu.ac.ir/article_16388_b9ddfeb90ec5dc7c590a43fc3c9c5d85.pdf

University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 54 114 2024 04 20 Experimental study on properties and resistance of local mineral pozzolanic concrete against fire and evaluation of its ability to reduce CO2 emissions Experimental study on properties and resistance of local mineral pozzolanic concrete against fire and evaluation of its ability to reduce CO2 emissions 211 224 16278 10.22034/ceej.2023.30485.2146 FA Mehdi Raftari Department of Civil Engineering, Khorramabad Branch, Islamic Azad University, Khorramabad, Iran Rahmat Madandoust Department of Civil Engineering, Khorramabad Branch, Islamic Azad University, Khorramabad, Iran & Department of Civil Engineering, University of Guilan, P.O. Box 3756, Rasht, Iran Reza Mahjoub Department of Civil Engineering, Khorramabad Branch, Islamic Azad University, Khorramabad, Iran Mojtaba Rangrazian Department of Civil Engineering, Khorramabad Branch, Islamic Azad University, Khorramabad, Iran Journal Article 2022 05 17 Finding a way to reduce cement consumption in concrete as the most widely used building materials, thereby reducing CO2 emissions from greenhouses, is a priority. In this paper, a natural pozzolan from Iran with suitable physical and chemical properties to replace part of cement in concrete, its introduction and engineering properties were investigated and its ability to reduce CO2 emissions was evaluated. In the experiments, steel and polypropylene fibers were used separately and hybrids with new mineral pozzolans were used. According to the previous optimizations, mineral pozzolan with a weight fraction of 15% of cement substitute was used in concrete. Experiments showed that concrete samples containing local mineral pozzolans and steel fibers had higher compressive strength. Pozzolanic concrete samples containing a combination of steel fibers and polypropylene had better performance in flexural strength. The strength of the samples was evaluated after exposure to 600 ° C. Samples containing steel fibers showed better compressive strength. Studies have shown; Adding 15% by weight of local mineral exchange pozzolan to cement in concrete can reduce CO2 emissions by 15.20%. Scanning electron microscope studies on samples containing local mineral pozzolan showed that this pozzolan prevented the increase in the amount of portlandite near the aggregates by creating a favorable pozzolanic reaction with portlandite and thus strengthened the boundary transition zone and the bond between the whole and Improves the matrix. The studied mineral pozzolan is effective in making green concrete. Finding a way to reduce cement consumption in concrete as the most widely used building materials, thereby reducing CO2 emissions from greenhouses, is a priority. In this paper, a natural pozzolan from Iran with suitable physical and chemical properties to replace part of cement in concrete, its introduction and engineering properties were investigated and its ability to reduce CO2 emissions was evaluated. In the experiments, steel and polypropylene fibers were used separately and hybrids with new mineral pozzolans were used. According to the previous optimizations, mineral pozzolan with a weight fraction of 15% of cement substitute was used in concrete. Experiments showed that concrete samples containing local mineral pozzolans and steel fibers had higher compressive strength. Pozzolanic concrete samples containing a combination of steel fibers and polypropylene had better performance in flexural strength. The strength of the samples was evaluated after exposure to 600 ° C. Samples containing steel fibers showed better compressive strength. Studies have shown; Adding 15% by weight of local mineral exchange pozzolan to cement in concrete can reduce CO2 emissions by 15.20%. Scanning electron microscope studies on samples containing local mineral pozzolan showed that this pozzolan prevented the increase in the amount of portlandite near the aggregates by creating a favorable pozzolanic reaction with portlandite and thus strengthened the boundary transition zone and the bond between the whole and Improves the matrix. The studied mineral pozzolan is effective in making green concrete.

https://ceej.tabrizu.ac.ir/article_16278_4b4300c7b32228cd10e41457c9db3b57.pdf