International Journal of Geosynthetics and Ground Engineering
Encountering weak fine-grained soil presents a significant challenge during highway construction.... more Encountering weak fine-grained soil presents a significant challenge during highway construction. The conventional approach to address this challenge involves incorporating calcium-based stabilizers, particularly cement, for stabilization. However, despite its widespread use, the application of cement for soil stabilization has adverse environmental consequences. Accordingly, finding alternative methods to minimize cement usage has become a prominent area of research, from researchers worldwide. This study evaluates the effectiveness of utilizing discarded polyethylene terephthalate (PET) bottle shreds as soil reinforcement alongside lower cement contents. To this end, soil samples were mixed with varied contents of two grades of shredded PET. The ground PET pellets, which displayed diverse shapes, demonstrated properties resembling fibres. Compacted samples were subjected to CBR to determine optimum PET content. Strength, small-strain stiffness and durability of soils in original s...
Abstract The study explored the experimental conditions to enable co-metabolism of olive mill was... more Abstract The study explored the experimental conditions to enable co-metabolism of olive mill wastewater, (OMW), pretreated by Fenton-based oxidation, when combined with a compatible waste in a sequencing batch reactor (SBR). For this purpose, peptone mixture was used as the synthetic substrate, well tested for its similar biodegradation character with sewage. Emphasis was placed upon the degree of dilution that could be afforded without upsetting the performance of biological process. The SBR operation involved four cycles a day, at a sludge age of 8.0 days. The COD level of the peptone mixture feeding was kept constant as 400 mg/L, to simulate a relatively weak sewage. After acclimation of biomass to the synthetic substrate, SBR operation continued for 105 days with gradually increasing OMW additions in four consecutive phases with COD increments between 40 and 100 mg/L and no OMW addition in the last phase. Co-metabolism with complete removal of biodegradable COD in OMW could be sustained under cyclic steady-state conditions of each phase. Biodegradation characteristics of OMW could be defined in terms of COD fractionation and process kinetics; they were used in model simulation of in-cycle COD profiles at the end of each cycle. The study advocated co-metabolism as a novel and sustainable approach of wastewater management of olive mill wastewater, when properly diluted in sewage or a compatible wastewater and jointly subjected to biological treatment, a pre-requisite for OMW. It is believed that the proposed approach embodies all scientific and practical attributes to provide the long-awaited solution for this industry.
IOP Conference Series: Earth and Environmental Science
Nowadays plastic has a major role in our life use, but the increased usage of it led to a serious... more Nowadays plastic has a major role in our life use, but the increased usage of it led to a serious challenge which is plastic waste. Plastic waste is increasing day by day and which led to many bad disposal methods like burning and due to that there are many environmental and pollution problems. Therefore, there is a need to seek for safe and effective disposal methods to protect our plant and next generations’ future. One of the effective and safe solutions is using plastic waste in civil engineering construction as this solution is eco-friendly where it will provide a safe disposal as well as in engineering there is always a seek for economical materials and as plastic waste is almost for free. In addition, adding these materials may improve the properties of the construction materials. This article reviews all the published trials of using waste plastic bottles fibers as soil improvement material to examine the effectiveness of using this material as a reinforcing material in impr...
There are various environmental risks in both the construction and operation phases of huge civil... more There are various environmental risks in both the construction and operation phases of huge civil projects such as dam construction. As a result, it is critical to implement appropriate risk control and risk mitigation measures before the initiation of the activities posed by these schemes. The goal of this research is to identify and categorize the environmental risks posed by the Amirkabir Dam during its construction and operation phases. After identifying the risks, the risk factors were prioritized using the FMEA method, with the risks being ranked according to their severity, probability of occurrence, and ability to detect. The study’s findings revealed that the highest risk in the dam construction stage is associated with road construction and vehicle exhaust gases (RPNs of 280 and 252, respectively), and the highest risk in the operation phase is associated with borrow area overuse (erosion and sediment downstream of the dam) (RPN of 280).
Building on expansive soil is risky due to its high compressibility, low shear strength, and diff... more Building on expansive soil is risky due to its high compressibility, low shear strength, and differential settlement. This study evaluates the potential of the use of sodium hydroxide (NaOH) as an additive to improve the stability of clay. For this research, the compaction properties namely Dry Density, Optimum Moisture Content, Atterberg Limits, and Unconfined Compressive Strength were performed on soil samples prepared with different percentages of NaOH (0%, 5%, 10%, 15%, and 20%). In this work, the clay sample was obtained from a highway project site near the Haspolat village in the eastern suburb of North Nicosia, Cyprus. No works of such have been done in the area. The results indicated that NaOH can be added to improve the engineering properties of the soil. Moreover, this paper presents a comparative study between an empirical equation (Quadratic model (QM)), Multilayer Feed-Forward Neural Network (MFFNN), Cascade Feed-forward Neural Network (CFNN), Radial Basis Neural Network (RBNN), and Elman neural network (ENN)) and multiple linear regression (MLR) for modeling the stress–strain behavior of CS15 (contains 85% of soil and 15% of NaOH). The coefficient of determination, root mean squared error, mean absolute error, Nash–Sutcliffe efficiency, and Willmott's index of the agreement were used to select the best predictive model. The results indicate that all the developed models are expedient in predicting the stress–strain behavior of treated soil. Furthermore, the findings demonstrated that the QM model performed well and presented high accuracy in modeling the stress–strain behavior.
IOP Conference Series: Earth and Environmental Science, 2020
The goal of this review study is to define the use of ceramic wastes as a raw material in soil st... more The goal of this review study is to define the use of ceramic wastes as a raw material in soil structures and the construction of road pavement subgrades. The global output of ceramic waste powder (CWP) produced during the final polishing phase of ceramic tiles exceeds 22 billion tones. The application of (CWP) in landfill sites could create major environmental issues for soil, water and climate. It has been calculated that about 30% of the daily growth in the ceramic industry goes to waste. By trying to reduce this material, we can provide a big benefit of minimizing the use of natural products, decreasing the amount of money used and enhancing land conditions, based on the quantities we can use. Such wastes cannot be processed in any manner and thus create issues with the disposal and loss to the industry. Ceramic waste is strong, durable and resistant to all kind of declining powers, and these properties allow it to be substitute for replacements. Using various quantities of cera...
Plastic pollution is one of the most pressing environmental concerns today. Plastic wastes are us... more Plastic pollution is one of the most pressing environmental concerns today. Plastic wastes are usually left unattended and as they resist biodegradation, they pile up in the soil and in the sea environments. Therefore, their recovery and reuse in different applications should be recognized as the best remedial action. This study presents a tangible example of plastic reuse, where a sustainable method is proposed and tested by altering the plastic waste into useful material for soil stabilization. For this purpose, collected waste plastic bags were shredded into strips and they were mixed with clayey soil by 0.2, 0.3, and 0.4% of weight. The effect of adding plastic strips into soil on the mechanical properties of the mixture was then monitored through an experimental survey. Results depicted a meaningful increase in the California bearing ratio (CBR) and unconfined compressive strength (UCS) with increased percentage of plastic strips from 0 to 0.4%. The maximum dry density (MDD) was observed at 0.2% of plastic additions. It was concluded that mixing certain amounts of plastic bag strips to the clay samples could improve the geotechnical properties to a level where the mixture could be used as a subgrade layer while providing a useful reuse option that would potentially reduce plastic piling in the environment.
IOP Conference Series: Earth and Environmental Science, 2020
Waste disposal is one of the important problems in the world. In general, wastes are categorized ... more Waste disposal is one of the important problems in the world. In general, wastes are categorized into different groups, and there are some special landfills and methods for disposing of each of these waste materials. However, it should be noted that although there are some rules and regulations that try to reduce the impact of waste disposal, landfills have negative effects on soil, air, water, and natural life. One of the most important sources of pollution in landfills is the leachate that is generated by the decomposition of waste. Leachate can penetrate into the soil and water resources, contaminate them, and can affect human life. Leachate generation has five different phases and each of these phases contains some reactions that have a direct impact on the quality and quantity of leachate. Leachate has four main types of pollution and each of these pollutants can contaminate soil and water resources and be hazardous for aquatic and animals in the soil. In addition, some of thes...
IOP Conference Series: Materials Science and Engineering, 2020
Slope stability analysis and design of manmade slopes has always been a challenging geotechnical ... more Slope stability analysis and design of manmade slopes has always been a challenging geotechnical problem. Different methods have been developed and created to examine two and three dimensional slope models based on various methods of assumption and assessment. Throughout this study two limit equilibrium, and finite element methods has been used to examine the stability of the slope and to determine the critical slip surface of failure by using PLAXIS, FLAC/Slope and SLOPE/W software programs respectively. Different values of shear strength parameters were chosen to investigate the efficiency of these methods. Various values of unit weight, cohesion, internal friction angle, and their impact on the safety factor were examined. Comparing the results for factor of safety indicated that finite element calculation used in PLAXIS gives more conservative results by 0.5% compared to SLOPE/W program. FLAC/Slope was observed as the most complicated software and finite difference method genera...
ABSTRACT This paper studies the strength properties of compacted sand-bentonite landfill barrier ... more ABSTRACT This paper studies the strength properties of compacted sand-bentonite landfill barrier material with and without cement addition at different periods of aging. Test results indicated that strength values both in compression and tension increased up to threefold in cement added samples, as well as enhancing the ductile behavior. Cubic modulus, described as the slope of the elastic portion of the cubic compressive stress versus strain curves is determined along with initial and flexural moduli, and all the strength and moduli values were correlated with each other. Finally, it is concluded that there is a marked improvement in strength properties and moduli with cement inclusion and that the effect of aging has been very effective.
Proceedings of the 1st European Conference, E-UNSAT 2008, Durham, United Kingdom, 2-4 July 2008, 2008
ABSTRACT This article presents the preliminary findings of an experimental study conducted on uni... more ABSTRACT This article presents the preliminary findings of an experimental study conducted on uniform sand-bentonite mixtures, focussing on the investigation and prediction of the volume change and hydraulic properties of artificially prepared mixtures of natural bentonite (Na-smectite) and poorly graded fine sand. Compacted specimens of sand-bentonite mixtures with additions of 33%, 50% and 75% sand were tested to demonstrate the change in physical and mechanical properties as compared to the compacted bentonite with no sand, therefore obtaining the most feasible combination for achieving the required properties. Based on the experimental findings of swell-shrink behaviour, saturated hydraulic conductivity and soil-water characteristic behaviour, sand-bentonite mixtures with 75% sand proved to be quite effective in fulfilling the requirements for barriers in a semi-arid climate.
Plastic waste is increasing by time that caused huge challenges all over the world. Therefore, th... more Plastic waste is increasing by time that caused huge challenges all over the world. Therefore, there is a need for good ways to solve the environmental challenges. Also, there is another problem which is that many times weak soil faces the projects, the soil needs to be improved. The idea of this paper is to have a thorough review on literature to collect the data on reinforcing soil with waste plastic bags, where the plastic bags strips are reused as a soil stabilizing technique. This solution will be cost effective and eco-friendly and will solve soil weakness problem. This article reviews the works that has been carried out in this issue to find out the functionality of these waste strips as reinforcing material. From this paper the findings were that plastic bags can be used as an effective solution to improve soil strength while being eco-friendly and cost effective. It is noticed that addition of 0-2.5% plastic bags results in getting better property improvements. Regarding the dimensions of the additives it was found that the plastic strips with higher the aspect ratio lead to better test results. Finally, CBR, shear strength parameter and compaction characteristics of stabilized samples were visibly improved comparing to non-stabilized samples.
Liquefaction risk assessment is critical for the safety and economics of structures. As the soil ... more Liquefaction risk assessment is critical for the safety and economics of structures. As the soil strata of Ramsar area in north Iran is mostly composed of poorly graded clean sand and the ground water table is found at shallow depths, it is highly susceptible to liquefaction. In this study, a series of isotropic and anisotropic consolidated undrained triaxial tests were performed on reconstituted specimens of Ramsar sand to identify the liquefaction potential of the area. The specimens are consolidated isotropically to simulate the level ground condition, and anisotropically to simulate the soil condition on a slope and/or under a structure. The various states of soil behavior are studied by preparing specimens at different initial relative densities and applying different levels of effective stress. The critical state soil mechanics approach for identifying the liquefaction susceptibility is adopted and the observed phenomena are further explained in relation to the micro-mechanica...
International Journal of Geosynthetics and Ground Engineering
Encountering weak fine-grained soil presents a significant challenge during highway construction.... more Encountering weak fine-grained soil presents a significant challenge during highway construction. The conventional approach to address this challenge involves incorporating calcium-based stabilizers, particularly cement, for stabilization. However, despite its widespread use, the application of cement for soil stabilization has adverse environmental consequences. Accordingly, finding alternative methods to minimize cement usage has become a prominent area of research, from researchers worldwide. This study evaluates the effectiveness of utilizing discarded polyethylene terephthalate (PET) bottle shreds as soil reinforcement alongside lower cement contents. To this end, soil samples were mixed with varied contents of two grades of shredded PET. The ground PET pellets, which displayed diverse shapes, demonstrated properties resembling fibres. Compacted samples were subjected to CBR to determine optimum PET content. Strength, small-strain stiffness and durability of soils in original s...
Abstract The study explored the experimental conditions to enable co-metabolism of olive mill was... more Abstract The study explored the experimental conditions to enable co-metabolism of olive mill wastewater, (OMW), pretreated by Fenton-based oxidation, when combined with a compatible waste in a sequencing batch reactor (SBR). For this purpose, peptone mixture was used as the synthetic substrate, well tested for its similar biodegradation character with sewage. Emphasis was placed upon the degree of dilution that could be afforded without upsetting the performance of biological process. The SBR operation involved four cycles a day, at a sludge age of 8.0 days. The COD level of the peptone mixture feeding was kept constant as 400 mg/L, to simulate a relatively weak sewage. After acclimation of biomass to the synthetic substrate, SBR operation continued for 105 days with gradually increasing OMW additions in four consecutive phases with COD increments between 40 and 100 mg/L and no OMW addition in the last phase. Co-metabolism with complete removal of biodegradable COD in OMW could be sustained under cyclic steady-state conditions of each phase. Biodegradation characteristics of OMW could be defined in terms of COD fractionation and process kinetics; they were used in model simulation of in-cycle COD profiles at the end of each cycle. The study advocated co-metabolism as a novel and sustainable approach of wastewater management of olive mill wastewater, when properly diluted in sewage or a compatible wastewater and jointly subjected to biological treatment, a pre-requisite for OMW. It is believed that the proposed approach embodies all scientific and practical attributes to provide the long-awaited solution for this industry.
IOP Conference Series: Earth and Environmental Science
Nowadays plastic has a major role in our life use, but the increased usage of it led to a serious... more Nowadays plastic has a major role in our life use, but the increased usage of it led to a serious challenge which is plastic waste. Plastic waste is increasing day by day and which led to many bad disposal methods like burning and due to that there are many environmental and pollution problems. Therefore, there is a need to seek for safe and effective disposal methods to protect our plant and next generations’ future. One of the effective and safe solutions is using plastic waste in civil engineering construction as this solution is eco-friendly where it will provide a safe disposal as well as in engineering there is always a seek for economical materials and as plastic waste is almost for free. In addition, adding these materials may improve the properties of the construction materials. This article reviews all the published trials of using waste plastic bottles fibers as soil improvement material to examine the effectiveness of using this material as a reinforcing material in impr...
There are various environmental risks in both the construction and operation phases of huge civil... more There are various environmental risks in both the construction and operation phases of huge civil projects such as dam construction. As a result, it is critical to implement appropriate risk control and risk mitigation measures before the initiation of the activities posed by these schemes. The goal of this research is to identify and categorize the environmental risks posed by the Amirkabir Dam during its construction and operation phases. After identifying the risks, the risk factors were prioritized using the FMEA method, with the risks being ranked according to their severity, probability of occurrence, and ability to detect. The study’s findings revealed that the highest risk in the dam construction stage is associated with road construction and vehicle exhaust gases (RPNs of 280 and 252, respectively), and the highest risk in the operation phase is associated with borrow area overuse (erosion and sediment downstream of the dam) (RPN of 280).
Building on expansive soil is risky due to its high compressibility, low shear strength, and diff... more Building on expansive soil is risky due to its high compressibility, low shear strength, and differential settlement. This study evaluates the potential of the use of sodium hydroxide (NaOH) as an additive to improve the stability of clay. For this research, the compaction properties namely Dry Density, Optimum Moisture Content, Atterberg Limits, and Unconfined Compressive Strength were performed on soil samples prepared with different percentages of NaOH (0%, 5%, 10%, 15%, and 20%). In this work, the clay sample was obtained from a highway project site near the Haspolat village in the eastern suburb of North Nicosia, Cyprus. No works of such have been done in the area. The results indicated that NaOH can be added to improve the engineering properties of the soil. Moreover, this paper presents a comparative study between an empirical equation (Quadratic model (QM)), Multilayer Feed-Forward Neural Network (MFFNN), Cascade Feed-forward Neural Network (CFNN), Radial Basis Neural Network (RBNN), and Elman neural network (ENN)) and multiple linear regression (MLR) for modeling the stress–strain behavior of CS15 (contains 85% of soil and 15% of NaOH). The coefficient of determination, root mean squared error, mean absolute error, Nash–Sutcliffe efficiency, and Willmott's index of the agreement were used to select the best predictive model. The results indicate that all the developed models are expedient in predicting the stress–strain behavior of treated soil. Furthermore, the findings demonstrated that the QM model performed well and presented high accuracy in modeling the stress–strain behavior.
IOP Conference Series: Earth and Environmental Science, 2020
The goal of this review study is to define the use of ceramic wastes as a raw material in soil st... more The goal of this review study is to define the use of ceramic wastes as a raw material in soil structures and the construction of road pavement subgrades. The global output of ceramic waste powder (CWP) produced during the final polishing phase of ceramic tiles exceeds 22 billion tones. The application of (CWP) in landfill sites could create major environmental issues for soil, water and climate. It has been calculated that about 30% of the daily growth in the ceramic industry goes to waste. By trying to reduce this material, we can provide a big benefit of minimizing the use of natural products, decreasing the amount of money used and enhancing land conditions, based on the quantities we can use. Such wastes cannot be processed in any manner and thus create issues with the disposal and loss to the industry. Ceramic waste is strong, durable and resistant to all kind of declining powers, and these properties allow it to be substitute for replacements. Using various quantities of cera...
Plastic pollution is one of the most pressing environmental concerns today. Plastic wastes are us... more Plastic pollution is one of the most pressing environmental concerns today. Plastic wastes are usually left unattended and as they resist biodegradation, they pile up in the soil and in the sea environments. Therefore, their recovery and reuse in different applications should be recognized as the best remedial action. This study presents a tangible example of plastic reuse, where a sustainable method is proposed and tested by altering the plastic waste into useful material for soil stabilization. For this purpose, collected waste plastic bags were shredded into strips and they were mixed with clayey soil by 0.2, 0.3, and 0.4% of weight. The effect of adding plastic strips into soil on the mechanical properties of the mixture was then monitored through an experimental survey. Results depicted a meaningful increase in the California bearing ratio (CBR) and unconfined compressive strength (UCS) with increased percentage of plastic strips from 0 to 0.4%. The maximum dry density (MDD) was observed at 0.2% of plastic additions. It was concluded that mixing certain amounts of plastic bag strips to the clay samples could improve the geotechnical properties to a level where the mixture could be used as a subgrade layer while providing a useful reuse option that would potentially reduce plastic piling in the environment.
IOP Conference Series: Earth and Environmental Science, 2020
Waste disposal is one of the important problems in the world. In general, wastes are categorized ... more Waste disposal is one of the important problems in the world. In general, wastes are categorized into different groups, and there are some special landfills and methods for disposing of each of these waste materials. However, it should be noted that although there are some rules and regulations that try to reduce the impact of waste disposal, landfills have negative effects on soil, air, water, and natural life. One of the most important sources of pollution in landfills is the leachate that is generated by the decomposition of waste. Leachate can penetrate into the soil and water resources, contaminate them, and can affect human life. Leachate generation has five different phases and each of these phases contains some reactions that have a direct impact on the quality and quantity of leachate. Leachate has four main types of pollution and each of these pollutants can contaminate soil and water resources and be hazardous for aquatic and animals in the soil. In addition, some of thes...
IOP Conference Series: Materials Science and Engineering, 2020
Slope stability analysis and design of manmade slopes has always been a challenging geotechnical ... more Slope stability analysis and design of manmade slopes has always been a challenging geotechnical problem. Different methods have been developed and created to examine two and three dimensional slope models based on various methods of assumption and assessment. Throughout this study two limit equilibrium, and finite element methods has been used to examine the stability of the slope and to determine the critical slip surface of failure by using PLAXIS, FLAC/Slope and SLOPE/W software programs respectively. Different values of shear strength parameters were chosen to investigate the efficiency of these methods. Various values of unit weight, cohesion, internal friction angle, and their impact on the safety factor were examined. Comparing the results for factor of safety indicated that finite element calculation used in PLAXIS gives more conservative results by 0.5% compared to SLOPE/W program. FLAC/Slope was observed as the most complicated software and finite difference method genera...
ABSTRACT This paper studies the strength properties of compacted sand-bentonite landfill barrier ... more ABSTRACT This paper studies the strength properties of compacted sand-bentonite landfill barrier material with and without cement addition at different periods of aging. Test results indicated that strength values both in compression and tension increased up to threefold in cement added samples, as well as enhancing the ductile behavior. Cubic modulus, described as the slope of the elastic portion of the cubic compressive stress versus strain curves is determined along with initial and flexural moduli, and all the strength and moduli values were correlated with each other. Finally, it is concluded that there is a marked improvement in strength properties and moduli with cement inclusion and that the effect of aging has been very effective.
Proceedings of the 1st European Conference, E-UNSAT 2008, Durham, United Kingdom, 2-4 July 2008, 2008
ABSTRACT This article presents the preliminary findings of an experimental study conducted on uni... more ABSTRACT This article presents the preliminary findings of an experimental study conducted on uniform sand-bentonite mixtures, focussing on the investigation and prediction of the volume change and hydraulic properties of artificially prepared mixtures of natural bentonite (Na-smectite) and poorly graded fine sand. Compacted specimens of sand-bentonite mixtures with additions of 33%, 50% and 75% sand were tested to demonstrate the change in physical and mechanical properties as compared to the compacted bentonite with no sand, therefore obtaining the most feasible combination for achieving the required properties. Based on the experimental findings of swell-shrink behaviour, saturated hydraulic conductivity and soil-water characteristic behaviour, sand-bentonite mixtures with 75% sand proved to be quite effective in fulfilling the requirements for barriers in a semi-arid climate.
Plastic waste is increasing by time that caused huge challenges all over the world. Therefore, th... more Plastic waste is increasing by time that caused huge challenges all over the world. Therefore, there is a need for good ways to solve the environmental challenges. Also, there is another problem which is that many times weak soil faces the projects, the soil needs to be improved. The idea of this paper is to have a thorough review on literature to collect the data on reinforcing soil with waste plastic bags, where the plastic bags strips are reused as a soil stabilizing technique. This solution will be cost effective and eco-friendly and will solve soil weakness problem. This article reviews the works that has been carried out in this issue to find out the functionality of these waste strips as reinforcing material. From this paper the findings were that plastic bags can be used as an effective solution to improve soil strength while being eco-friendly and cost effective. It is noticed that addition of 0-2.5% plastic bags results in getting better property improvements. Regarding the dimensions of the additives it was found that the plastic strips with higher the aspect ratio lead to better test results. Finally, CBR, shear strength parameter and compaction characteristics of stabilized samples were visibly improved comparing to non-stabilized samples.
Liquefaction risk assessment is critical for the safety and economics of structures. As the soil ... more Liquefaction risk assessment is critical for the safety and economics of structures. As the soil strata of Ramsar area in north Iran is mostly composed of poorly graded clean sand and the ground water table is found at shallow depths, it is highly susceptible to liquefaction. In this study, a series of isotropic and anisotropic consolidated undrained triaxial tests were performed on reconstituted specimens of Ramsar sand to identify the liquefaction potential of the area. The specimens are consolidated isotropically to simulate the level ground condition, and anisotropically to simulate the soil condition on a slope and/or under a structure. The various states of soil behavior are studied by preparing specimens at different initial relative densities and applying different levels of effective stress. The critical state soil mechanics approach for identifying the liquefaction susceptibility is adopted and the observed phenomena are further explained in relation to the micro-mechanica...
Uploads
Papers by anoosheh iravanian