International Journal of Geotechnical Engineering, Apr 5, 2021
ABSTRACT In this research, concurrent employment of Waste Tire Textile Fibres (WTTFs) and lime in... more ABSTRACT In this research, concurrent employment of Waste Tire Textile Fibres (WTTFs) and lime in two types of low plastic clays (soil A and soil B) is investigated by performing various tests, namely, standard Proctor compaction, Direct Shear, UCS, CBR and Split Tensile Strength (STS). Fibre inclusion with an optimum weight content of 1.5% led to an improvement in strength parameters of soils. Cohesion and internal friction angle were enhanced as a result of lime-stabilization. Simultaneous employment of 1.5% of fibres and 6% of lime increased the UCS by 10.66 and 7.95 times in the examined clays. It was demonstrated that fibres compensated for the brittleness induced in the soil by lime admixture. Therefore, concurrent addition of lime and fibres produced excellent specimens in terms of both strength and ductility. Soil mixtures with an optimum fibre content of 1.5% increased the CBR value of soils A and B by 4.9% and 3%, respectively. Moreover, the concurrent addition of 1.5% fibres and 4% and more lime increased the CBR value by more than 100%. STS was also enhanced by fibres and lime addition. Concurrent reinforcement by 1.5% of fibres and stabilization by 6% of lime in soils A and B increased STS by 23.6 and 14.5 times, respectively.
International Journal of Geotechnical Engineering, 2021
ABSTRACT In this research, concurrent employment of Waste Tire Textile Fibres (WTTFs) and lime in... more ABSTRACT In this research, concurrent employment of Waste Tire Textile Fibres (WTTFs) and lime in two types of low plastic clays (soil A and soil B) is investigated by performing various tests, namely, standard Proctor compaction, Direct Shear, UCS, CBR and Split Tensile Strength (STS). Fibre inclusion with an optimum weight content of 1.5% led to an improvement in strength parameters of soils. Cohesion and internal friction angle were enhanced as a result of lime-stabilization. Simultaneous employment of 1.5% of fibres and 6% of lime increased the UCS by 10.66 and 7.95 times in the examined clays. It was demonstrated that fibres compensated for the brittleness induced in the soil by lime admixture. Therefore, concurrent addition of lime and fibres produced excellent specimens in terms of both strength and ductility. Soil mixtures with an optimum fibre content of 1.5% increased the CBR value of soils A and B by 4.9% and 3%, respectively. Moreover, the concurrent addition of 1.5% fibres and 4% and more lime increased the CBR value by more than 100%. STS was also enhanced by fibres and lime addition. Concurrent reinforcement by 1.5% of fibres and stabilization by 6% of lime in soils A and B increased STS by 23.6 and 14.5 times, respectively.
The final sections of main access roads to the cities require especial attention as the frequency... more The final sections of main access roads to the cities require especial attention as the frequency of accidents in these road sections are considerably higher than other parts of interurban roads. These road sections operate as an interface between the rural roads and urban streets. The previous researches available on this subject are limited and they have also mainly focused on a narrow range of factors contributing to the accidents in these areas. The main contribution of this research is to consider a relatively comprehensive range of potential factors , and to examine their impacts through the development and comparison of both conventional probabilistic models and Artificial Neural Network (ANN) models. For this purpose, information related to the main access roads of three major Iranian cities were collected. This information consisted of accident frequency data together with the field observations of traffic characteristics, road-way conditions and roadside features of these ...
Communications - Scientific letters of the University of Zilina, 2021
Despite the very important role of primary arteries and transportation network in providing relie... more Despite the very important role of primary arteries and transportation network in providing relief for regions affected by an earthquake and black spots, they have received less attention. Therefore, in the current study, at first, the status quo of the traffic black spots and safe regions was identified to predict the movement direction, evacuation of residents from their habitat and temporary residence using the region zoning. The trips were assigned to the network based on the trip distribution matrix and their relevant travel times both related to the crisis state. The results indicated that out of 94 traffic regions, located in the area under investigation, 7 regions were put in the very low risk or safe regions group and 10 traffic regions were put in a very high-risk group. Additionally, the results indicated that out of 794 links, located in the area under investigation, about 32 links will have a very undesirable status following an earthquake.
Intersections, as the critical elements and the major bottleneck points of urban street networks,... more Intersections, as the critical elements and the major bottleneck points of urban street networks, may have inconsistent performances in different countries. This is largely due to the fact that the factors affecting their performance e.g. driving behavior, vehicle characteristics, control methods, and environmental conditions may vary from one country to another. It is, therefore required to take into account these factors when developing or applying available models and methodologies for their capacity analysis or signal control setting. This is particularly important for the countries with heterogeneous and weak discipline traffic streams such as Iran. Meanwhile, estimating the saturation flow rate, which is a key parameter in capacity and delay analysis and in optimal timing of traffic signals, is of great importance. In this study, the possibility of identifying and or developing appropriate models for estimating the saturation flow rate at the signalized intersections in these ...
Aim:The aim of this research was to investigate the merits for further improvements of traffic op... more Aim:The aim of this research was to investigate the merits for further improvements of traffic operation on freeways and expressways through coordinated use of Ramp Metering and Variable Speed limit (VSL) control systems.Methods:In this research, the widely used ALINEA Ramp Metering strategy was coordinated with a rule-based VSL strategy so that the total flow entered from the upstream freeway and entry ramp is maintained below the merge downstream capacity. The developed algorithm was then examined on a freeway network comprising two merge and one diverge sections, using VISSIM microscopic simulation model. The performance of the simulated network was examined under three scenarios namely, No-control, Ramp Metering only and Ramp Metering plus VSL controls. The network performance under each scenario was then assessed and compared using three measures of performance namely, average travel time, overall delay and freeway throughput. The ANOVA test was used to analyze and compare the ...
This paper presents the results of a study of the approaches and methods used for variable speed ... more This paper presents the results of a study of the approaches and methods used for variable speed limit (VSL) control systems. The author maintains that it is essential to ensure that these systems are robust enough to produce the required changes in speed. Thus, the success of VSL Systems largely depends on the underlying approaches and methods used in their algorithms logic. VSL systems are designed to be employed in a rapidly changing environment to encourage uniform driving behavior and to meet specific objectives including: safety improvement; congestion reduction (e.g. via improving travel times and/or maximizing throughput), emissions reduction and energy conservation. The author first presents a critical review of different approaches and methods used for VSL, with emphasis on those currently implemented in real world. Then a number of suggestions for further improvements to the existing rule-based practical systems are provided. These suggestions are based on an assessment of the performance of existing systems, especially the UK system (known as Controlled Motorways). The paper concludes by calling for additional research on a network-oriented traffic control model for the management of incidents and congestion on a motorway corridor.
Applications and Innovations in Intelligent Systems IX, 2002
A microscopic simulation model, representing traffic behaviour in the vicinity of merges on motor... more A microscopic simulation model, representing traffic behaviour in the vicinity of merges on motorways, was applied to produce a set of data representing traffic patterns in the merge area, ramp metering rates, and the corresponding vehicle journey times. The data were used to develop an Artificial Neural Network (ANN) model, which anticipates the average journey time of mainline vehicles that enter an upstream section during a 30s interval.
This paper studies a permutation flow shop scheduling problem with deteriorating jobs. Deteriorat... more This paper studies a permutation flow shop scheduling problem with deteriorating jobs. Deteriorating jobs are the jobs which the processing time depends on the waiting time before process starts. A particle swarm optimization algorithm with and without a proposed local search is developed to determine a job sequence with minimization of the total tardiness criterion. Furthermore, a simulated annealing is proposed to solve the problem. We compare the performance of these algorithms to achieve an optimal or near optimal solution. It is concluded that the particle swarm optimization algorithm with local search gives promising solutions. The quality of solution obtained by particle swarm optimization algorithm with local search is superior to that of the simulated annealing algorithm, but the simulated annealing algorithm takes shorter time to find a schedule solution.
International Journal of Geotechnical Engineering, Apr 5, 2021
ABSTRACT In this research, concurrent employment of Waste Tire Textile Fibres (WTTFs) and lime in... more ABSTRACT In this research, concurrent employment of Waste Tire Textile Fibres (WTTFs) and lime in two types of low plastic clays (soil A and soil B) is investigated by performing various tests, namely, standard Proctor compaction, Direct Shear, UCS, CBR and Split Tensile Strength (STS). Fibre inclusion with an optimum weight content of 1.5% led to an improvement in strength parameters of soils. Cohesion and internal friction angle were enhanced as a result of lime-stabilization. Simultaneous employment of 1.5% of fibres and 6% of lime increased the UCS by 10.66 and 7.95 times in the examined clays. It was demonstrated that fibres compensated for the brittleness induced in the soil by lime admixture. Therefore, concurrent addition of lime and fibres produced excellent specimens in terms of both strength and ductility. Soil mixtures with an optimum fibre content of 1.5% increased the CBR value of soils A and B by 4.9% and 3%, respectively. Moreover, the concurrent addition of 1.5% fibres and 4% and more lime increased the CBR value by more than 100%. STS was also enhanced by fibres and lime addition. Concurrent reinforcement by 1.5% of fibres and stabilization by 6% of lime in soils A and B increased STS by 23.6 and 14.5 times, respectively.
International Journal of Geotechnical Engineering, 2021
ABSTRACT In this research, concurrent employment of Waste Tire Textile Fibres (WTTFs) and lime in... more ABSTRACT In this research, concurrent employment of Waste Tire Textile Fibres (WTTFs) and lime in two types of low plastic clays (soil A and soil B) is investigated by performing various tests, namely, standard Proctor compaction, Direct Shear, UCS, CBR and Split Tensile Strength (STS). Fibre inclusion with an optimum weight content of 1.5% led to an improvement in strength parameters of soils. Cohesion and internal friction angle were enhanced as a result of lime-stabilization. Simultaneous employment of 1.5% of fibres and 6% of lime increased the UCS by 10.66 and 7.95 times in the examined clays. It was demonstrated that fibres compensated for the brittleness induced in the soil by lime admixture. Therefore, concurrent addition of lime and fibres produced excellent specimens in terms of both strength and ductility. Soil mixtures with an optimum fibre content of 1.5% increased the CBR value of soils A and B by 4.9% and 3%, respectively. Moreover, the concurrent addition of 1.5% fibres and 4% and more lime increased the CBR value by more than 100%. STS was also enhanced by fibres and lime addition. Concurrent reinforcement by 1.5% of fibres and stabilization by 6% of lime in soils A and B increased STS by 23.6 and 14.5 times, respectively.
The final sections of main access roads to the cities require especial attention as the frequency... more The final sections of main access roads to the cities require especial attention as the frequency of accidents in these road sections are considerably higher than other parts of interurban roads. These road sections operate as an interface between the rural roads and urban streets. The previous researches available on this subject are limited and they have also mainly focused on a narrow range of factors contributing to the accidents in these areas. The main contribution of this research is to consider a relatively comprehensive range of potential factors , and to examine their impacts through the development and comparison of both conventional probabilistic models and Artificial Neural Network (ANN) models. For this purpose, information related to the main access roads of three major Iranian cities were collected. This information consisted of accident frequency data together with the field observations of traffic characteristics, road-way conditions and roadside features of these ...
Communications - Scientific letters of the University of Zilina, 2021
Despite the very important role of primary arteries and transportation network in providing relie... more Despite the very important role of primary arteries and transportation network in providing relief for regions affected by an earthquake and black spots, they have received less attention. Therefore, in the current study, at first, the status quo of the traffic black spots and safe regions was identified to predict the movement direction, evacuation of residents from their habitat and temporary residence using the region zoning. The trips were assigned to the network based on the trip distribution matrix and their relevant travel times both related to the crisis state. The results indicated that out of 94 traffic regions, located in the area under investigation, 7 regions were put in the very low risk or safe regions group and 10 traffic regions were put in a very high-risk group. Additionally, the results indicated that out of 794 links, located in the area under investigation, about 32 links will have a very undesirable status following an earthquake.
Intersections, as the critical elements and the major bottleneck points of urban street networks,... more Intersections, as the critical elements and the major bottleneck points of urban street networks, may have inconsistent performances in different countries. This is largely due to the fact that the factors affecting their performance e.g. driving behavior, vehicle characteristics, control methods, and environmental conditions may vary from one country to another. It is, therefore required to take into account these factors when developing or applying available models and methodologies for their capacity analysis or signal control setting. This is particularly important for the countries with heterogeneous and weak discipline traffic streams such as Iran. Meanwhile, estimating the saturation flow rate, which is a key parameter in capacity and delay analysis and in optimal timing of traffic signals, is of great importance. In this study, the possibility of identifying and or developing appropriate models for estimating the saturation flow rate at the signalized intersections in these ...
Aim:The aim of this research was to investigate the merits for further improvements of traffic op... more Aim:The aim of this research was to investigate the merits for further improvements of traffic operation on freeways and expressways through coordinated use of Ramp Metering and Variable Speed limit (VSL) control systems.Methods:In this research, the widely used ALINEA Ramp Metering strategy was coordinated with a rule-based VSL strategy so that the total flow entered from the upstream freeway and entry ramp is maintained below the merge downstream capacity. The developed algorithm was then examined on a freeway network comprising two merge and one diverge sections, using VISSIM microscopic simulation model. The performance of the simulated network was examined under three scenarios namely, No-control, Ramp Metering only and Ramp Metering plus VSL controls. The network performance under each scenario was then assessed and compared using three measures of performance namely, average travel time, overall delay and freeway throughput. The ANOVA test was used to analyze and compare the ...
This paper presents the results of a study of the approaches and methods used for variable speed ... more This paper presents the results of a study of the approaches and methods used for variable speed limit (VSL) control systems. The author maintains that it is essential to ensure that these systems are robust enough to produce the required changes in speed. Thus, the success of VSL Systems largely depends on the underlying approaches and methods used in their algorithms logic. VSL systems are designed to be employed in a rapidly changing environment to encourage uniform driving behavior and to meet specific objectives including: safety improvement; congestion reduction (e.g. via improving travel times and/or maximizing throughput), emissions reduction and energy conservation. The author first presents a critical review of different approaches and methods used for VSL, with emphasis on those currently implemented in real world. Then a number of suggestions for further improvements to the existing rule-based practical systems are provided. These suggestions are based on an assessment of the performance of existing systems, especially the UK system (known as Controlled Motorways). The paper concludes by calling for additional research on a network-oriented traffic control model for the management of incidents and congestion on a motorway corridor.
Applications and Innovations in Intelligent Systems IX, 2002
A microscopic simulation model, representing traffic behaviour in the vicinity of merges on motor... more A microscopic simulation model, representing traffic behaviour in the vicinity of merges on motorways, was applied to produce a set of data representing traffic patterns in the merge area, ramp metering rates, and the corresponding vehicle journey times. The data were used to develop an Artificial Neural Network (ANN) model, which anticipates the average journey time of mainline vehicles that enter an upstream section during a 30s interval.
This paper studies a permutation flow shop scheduling problem with deteriorating jobs. Deteriorat... more This paper studies a permutation flow shop scheduling problem with deteriorating jobs. Deteriorating jobs are the jobs which the processing time depends on the waiting time before process starts. A particle swarm optimization algorithm with and without a proposed local search is developed to determine a job sequence with minimization of the total tardiness criterion. Furthermore, a simulated annealing is proposed to solve the problem. We compare the performance of these algorithms to achieve an optimal or near optimal solution. It is concluded that the particle swarm optimization algorithm with local search gives promising solutions. The quality of solution obtained by particle swarm optimization algorithm with local search is superior to that of the simulated annealing algorithm, but the simulated annealing algorithm takes shorter time to find a schedule solution.
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