Journal of Engineering and Sustainable Development, Mar 1, 2023
The civil aviation demand forecast is a carefully formed perspective for airport system activitie... more The civil aviation demand forecast is a carefully formed perspective for airport system activities. Its main use is to predict possible needs for the planning and financial management processes for air carriers and civil aviation authorities. It is vital to conduct frequent analyses and projections of demand in order to meet their customers' expectations by balancing supply and demand and staying abreast of the ever-changing aviation industry. The purpose of this paper is to establish a mathematical relationship between the socioeconomic explanatory factors such as (population, Gross Domestic Product (GDP), consumption expenditure, rate of exchange, industry, imports, and exports) and activities (passenger movements and aircraft operations) at Baghdad International Airport in order to develop an econometric model. The required data had been collected for the past ten years. Eight models were developed depending on one or more of the explanatory variables using SPSS software, and they were then subjected to cross-comparison to see which model was more robust. According to the findings of the statistics, the gross domestic product, population size, and consumption expenditure are the most appropriate explanatory variables that have a significant impact on these activities, where they had a high R2 and F-statistics value equal to 90% and 73.442, respectively, for the model of air passengers and GDP and 90% and 48.737 for the model of flight operations and GDP.
International journal of electrical and computer engineering systems, Dec 21, 2022
Predicting conceptual costs is among the essential criteria in project decision-making at the ear... more Predicting conceptual costs is among the essential criteria in project decision-making at the early stages of civil engineering disciplines. The cost estimation model availability that may help in the early stages of a project could be incredibly advantageous in respect of cost alternatives and more extraordinary cost-effective solutions periodically. There is a lack of case datasets. Most of the proposed dataset was inefficient. This study offers a new data set that includes the elements of road construction and economic advantages in the year of project construction. Real project data for rural roads in the State of Iraq / Diyala Governorate for the years 2012 to 2021 have use to train a predictive model with a high rate of accuracy based on machine learning (ML) methods. Ridge and Least Absolute Shrinkage and Selection Operator (LASSO) Regressions, K Nearest Neighbors (k-NN), and Random Forest (RF) algorithms have employ to create models for estimating road construction costs based on real-world data. The Root Mean Square Error (RMSE), Mean Absolute Percentage Error (MAPE), and R-squared (R2) coefficient of determination are utilize to assess the models' performance. The analysis indicated that the RR is the best model for road construction costs, with results R2 = 1.0, MAPE =0.00, and RMSE=0.00. The results showed that the cost estimates were accurate and aligned with the project bids.
Mathematical modelling of engineering problems, Dec 13, 2022
The aviation authorities have long been impacted by fluctuations in demand, which are often cause... more The aviation authorities have long been impacted by fluctuations in demand, which are often caused by the aviation industry's cyclical nature. It is affected mainly by many endogenous or exogenous variables. Despite that, the airport authorities and air carrier management make significant efforts to deal with fluctuating demand. This paper analyzed the factors influencing demand at Baghdad International Airport, based on the pertinent local socioeconomic data such as "population size," "GDP," and "terrorism effect," as well as system-based factors related to aviation activities and airport characteristics for the past ten years, to develop a system dynamics simulation model by which the causes of fluctuation are highlighted in order to predict the magnitude and timing of the increment or decline in an offer to minimize losses to all parties in the airport system. The simulation results demonstrated very high goodness of fit with the actual data, producing R 2 values of 0.865 and 0.86 for the departing and arriving passengers, respectively. Even though Iraq's unstable political and economic situation led to the interaction between the different demand drivers, external factors have a bigger effect on the country's need for air travel, causing demand shocks that take a long time to recover from.
A range of stabilisers for poor quality subgrade soils have been developed to promote road constr... more A range of stabilisers for poor quality subgrade soils have been developed to promote road constructions. Many of them are becoming more popular depending on their effectiveness. The purpose behind this research is to identify the relative efficacy of many physical and chemical stabilisation techniques for enhancing the properties of three types of local Iraqi subgrade soils. The comparison of the samples is based on the CBR tests. The AASHTO (1993) flexible pavement design was used to compute the pavement thickness requirements. The soil samples A, B and C have a natural CBR values of 3.8, 3.9 and 4, respectively, on which the physical stabilisers of Powdered rock (PR), grained recycled concrete (GRC), and recycled crumb rubber grains (CR) were employed, while Quicklime (QL) and activated fly ash (AFA) were both utilised as chemical stabilisers. The stabilisation with 15 % of AFA proved to be the most applicable method for soil types A and B for reducing the pavement thickness requirements by 51 % and 32 %, respectively, with a reasonable financial feasibility for both. The same feasibility is proven when stabilising soil type C with 15 % of GRC, which reduces the pavement thickness by 25.7 %.
Many cities in Diyala governorate are su ering from tra c congestion due to high percentage of th... more Many cities in Diyala governorate are su ering from tra c congestion due to high percentage of through tra c. One of the most applicable solutions to such problem is the construction of ring road by which the through tra c is avoided. In this research, Baqubah city is subjected to economic analyses in order to determine whether the establishment of a peripheral ring road to downgrade the tra c congestion in the city center would be economically feasible. e planned road is divided into three segments linking the three major entries to the city. e rst segment is already existing, while the second and third segments are following a predetermined orbital route that has not been utilized yet. Hence, the rst segment is not considered in the economic analyses, which included the second and third. e tra c data was collected for all entries, and then the fractions of tra c that expected to utilize the new ring road were estimated and projected for the design lifetime of the road taken as 20 years after two years of design and construction. e suggested road was proved pro table by the use of two economic parameters: the rst is the bene t cost ratio, which returned the values of 7.44 and 5.92, for the second and third segments, respectively. e net present value calculations revealed the values of $50,399,966 and $43,991,883 for the second and third segments, respectively.
Periodicals of Engineering and Natural Sciences (PEN), Mar 13, 2022
Mobility Demand Management initiatives are seen globally as a solution to the elimination of poll... more Mobility Demand Management initiatives are seen globally as a solution to the elimination of pollution and daily effects in off-road regions. In order to allow improvements on attainable comfort, such steps must have an effect. The High Occupancy Driver Carpool Lane is one of the TDM steps. HOV lanes are not utilized, with 81% of HOV locaters resulting streams under1400 vehicles per track during the PM peak hour strategy. This research is fitting in the Pune and Mumbai districts of India. HOV channels bear a 20 percent cap levy, reaching the highest advancement of 1600 Vphpl at 45 mph over the most drastic stream over 2000 Vphpl at 60 mph as a general justification for GP routes. HOV lanes deliver no investment funds for driving time. In general, HOV lanes decrease considerably as the usually helpful pathways are enabled to be clogged. In spite of these discoveries, HOV offices can take on a valuable job in the framework of all-around supervision of the expressway in India. Basically, where there is a meaning, they will be useful.
This study deals with the evaluation of the stabilization of several samples of soft soil with so... more This study deals with the evaluation of the stabilization of several samples of soft soil with some chemical and physical additives. The intention is to amend the weak properties of these soils summarized in low bearing capacity and high settlement. The used stabilizers are quicklime, class F fly ash activated by cement, rock powder, crushed waste concrete, and tire crumb rubber. The paper investigated the effects of these stabilizers by unconfined compression test that considers very effective geotechnical test for measuring the ability of soils to bear structures constructed on them especially when used additives. This test was carried out on three samples of soils. They were classified by (UCSC) as (CL) soft soils. They were also classified by (AASHTO) as (A-7-6), (A-6), and (A-6) are rated as fair to poor subgrades in (AASHTO). The results of (UCS) test for each of the five additives used were compared according to the responding of each soil samples used. The (UCS) test was conducted in this study on sixty samples of soils before and after treatment and under the basics of the Proctor compaction test at optimum moisture content and maximum dry density. The results showed that the rock powder was the most suitable stabilizer that gave best results of improvement reached to 900% at 25% percent by dry weight of soil, crushed waste concrete came after it that gave treatment 683% at 15%, class F fly ash activated by cement followed the two formers which increased strength 533% at 15%, quicklime after that in an amendment 517% at 9% and finally tire crumb rubber that stabilized the soil 500% at 4%. In the literature, these materials founded to be very efficient in the stabilization of soils in their physical and chemical properties like increasing bearing capacity and reducing settlement of soil.
DIYALA JOURNAL OF ENGINEERING SCIENCES, Jun 16, 2021
Gets in the world at this time continued growth and rapid development in the whole aspects of lif... more Gets in the world at this time continued growth and rapid development in the whole aspects of life. The urgent needing accomplished that is in civil engineering demands like the construction of houses, schools, hospitals, roads, and other structures. Because of that and for economic and security reasons; classifying soil and knowing its bearing capacity appeared to be very necessary conditions that offer a large domain of benefits that could not be counted. This study focused on classifying and determining the bearing capacity of some samples of soil that classified as soft soils of Baquba city the center of Diyala governorate in Iraq. Then trying to increase their bearing capacity. The California Bearing Ratio (CBR) was used in the paper to define soil strength because it is considered a force measuring parameter. Five elected physical and chemical treatments were used in predetermined percents taken from the literature and suited the kind of soil. They were quicklime, class F fly ash activated by cement, rock powder, crushed waste concrete, and crumb rubber of tires. The treatment that was the best among the five used methods was by the rock powder that improved CBR value by 570% in soil samples A used.
DIYALA JOURNAL OF ENGINEERING SCIENCES, Dec 1, 2018
Many models were introduced to estimate the roundabout entry capacity from 1980s until now. In th... more Many models were introduced to estimate the roundabout entry capacity from 1980s until now. In the United States, transportation agencies adopted three different models from 1994 until 2010. The Austroads, the UK, and the HCM 2010 methods. In this paper, these three methods were used to analyze the field traffic data of Al-Quds roundabout, located near Baqubah City, simultaneously by utilizing a system dynamics model. The collected data included turning movements, circulating flows, and field calculated entry capacities whenever possible during the observation period which lasted for 14 consecutive hours. A comparison is then conducted on the resulting entry capacities and their variation over time. The results showed that the calculated capacity according to Austroads method is the highest at all times while the UK method was always a little lower and the HCM 2010 method was always the least on all entries. The UK method capacity estimates were the closest to the field measured capacities for they returned the least RMSE on all entries. Field capacities showed some tendency towards the Austroads results in the north and south bound entries which carry about 66% of the total traffic. While, field capacities showed more proximity towards the HCM capacity results in the east and the west bound entries which carry 34% of the total traffic.
DIYALA JOURNAL OF ENGINEERING SCIENCES, Dec 1, 2016
In airport planning process, there is always a crucial need for good and reliable air traffic dem... more In airport planning process, there is always a crucial need for good and reliable air traffic demand estimate. It is equally important for airport authorities and airline carriers, for in the case of under estimated demand, there would be frequent congestions and delays. Conversely; overestimates would lead to unjustified expenditure which may lead to financial problems to all parties. The accurate and reliable models are not highly sophisticated in nature. In this paper, two econometric models were developed to forecast the passenger enplanements in two of the busiest airports in the United States of America. Many national and local socioeconomic variables were analyzed to come up with simple, yet accurate models. It was found that the total aggregate variables including per capita gross domestic production and population, have more influence on demand in the Hartsfield-Jackson Atlanta International Airport than the local variables, while the same factors, but in their regional scale, proofed to be more influencing in the case of John F Kennedy International Airport.
International Journal of Design & Nature and Ecodynamics, Apr 27, 2022
The complex nature of urban growth in cities whose population is exponentially increasing require... more The complex nature of urban growth in cities whose population is exponentially increasing requires a comprehensive understanding to create a precise and descriptive modelling. In order to identify the main factors that influence the behavior of such complex growth and consequently recognize the most applicable future projection to the growth in each urban category, a system dynamics model was developed in which all pertinent variables are incorporated. This model was proven to be capable of simulating the urban growth in Baquba city for some six decades from 1957 to 2017. The simulation results showed very high goodness of fit with the historical records with an R2 ranging between 0.987 and 0.997 proving the validity and applicability of the model. The interaction between various urban categories showed that the road network area was negatively influenced mainly by the rapid growth of residential and public areas. The future projections of this model to the target year of 2035 showed that the residential, public, commercial and industrial categories are increasing by; 55%, 84%, 40%, and 19% respectively. The road area has also increased by 19% in the same projection gaining more expansion than what it got in the last three decades prior to 2017.
International Journal of Design & Nature and Ecodynamics, Oct 29, 2021
With the growing demand for air transportation and limited capacity at Baghdad International airp... more With the growing demand for air transportation and limited capacity at Baghdad International airport (BIAP), there is a need to increase the capacity of airport systems in the middle district of Iraq. The increased use of secondary airports has been and is expected to be one of the key mechanisms by which future demand is met in congested metropolitan areas. This paper analyzed the factors influencing the emergence of secondary airports in the Iraqi middle district and the dynamics of multi-airport systems. A system dynamics model was developed to simulate the relationship between the core airport in Baghdad and three potential secondary airports, one in each adjacent governorate. The model takes under consideration such characteristics as; capacity, location, proximity to populated communities, and ground transportation services for each airport. the main outcomes of this model are; the passenger's persuasion in an airport, which reflects their propensity to use this particular airport, and the predicted number of annual passengers in each airport. The system dynamics model was consulted twice. The outcomes of the first run facilitated the economic analyses of the secondary airports on which the sequence of the airports emergence was determined, and it also showed that the new airport feasibility is highly affected by the location, due to the influence on the road user cost for passengers, in addition to the capital expenses. The second run of the model helped in predicting the time schedule and interval between an airport emergence and the other. If the new airports have an equal capacity of one million passenger per year, the expected timing for the emergence is in 2023, 2027, and 2032 for the airports in Balad, Habbaniyah, and Baquba respectively.
DIYALA JOURNAL OF ENGINEERING SCIENCES, Jun 16, 2021
Variation Orders is often a reason for construction projects exceeding projects budget and delays... more Variation Orders is often a reason for construction projects exceeding projects budget and delays; it is a global problem, particularly intensive in the case of a recession of the local economy and stagnation. In Iraq, all the projects have delays in completion, and the cost affects because of the variation orders, which are not well managed. The objective of this study was to identify the key causes responsible for the variation order in construction projects in Iraq using the system dynamic. System's dynamics is the discipline of academics and rooted initially been in management and the engineering sciences. The data relating to the performance of construction projects from 27 projects adopted by Diyala University were collected. Personal interviews and questionnaires survey to the selected projects of specialized engineers were done. The results revealed that the size of variation orders in Iraqi construction projects was high, and 13 key causative factors led to variation orders. The variation in cost was the most influential factor effecting the construction project in Iraq. When variation orders in a cost increased, the owner's opinion decreased. When the external factors increased, cost variation orders increased. It was concluded that minimizing the variation orders was very important to realize the cost in the construction projects. Therefore, the authority management and project managers must make a plan to address these key causes in future projects to ensure their success.
Journal of Engineering and Sustainable Development
The civil aviation demand forecast is a carefully formed perspective for airport system activitie... more The civil aviation demand forecast is a carefully formed perspective for airport system activities. Its main use is to predict possible needs for the planning and financial management processes for air carriers and civil aviation authorities. It is vital to conduct frequent analyses and projections of demand in order to meet their customers' expectations by balancing supply and demand and staying abreast of the ever-changing aviation industry. The purpose of this paper is to establish a mathematical relationship between the socioeconomic explanatory factors such as (population, Gross Domestic Product (GDP), consumption expenditure, rate of exchange, industry, imports, and exports) and activities (passenger movements and aircraft operations) at Baghdad International Airport in order to develop an econometric model. The required data had been collected for the past ten years. Eight models were developed depending on one or more of the explanatory variables using SPSS software, and...
Mathematical modelling of engineering problems, Dec 13, 2022
The aviation authorities have long been impacted by fluctuations in demand, which are often cause... more The aviation authorities have long been impacted by fluctuations in demand, which are often caused by the aviation industry's cyclical nature. It is affected mainly by many endogenous or exogenous variables. Despite that, the airport authorities and air carrier management make significant efforts to deal with fluctuating demand. This paper analyzed the factors influencing demand at Baghdad International Airport, based on the pertinent local socioeconomic data such as "population size," "GDP," and "terrorism effect," as well as system-based factors related to aviation activities and airport characteristics for the past ten years, to develop a system dynamics simulation model by which the causes of fluctuation are highlighted in order to predict the magnitude and timing of the increment or decline in an offer to minimize losses to all parties in the airport system. The simulation results demonstrated very high goodness of fit with the actual data, producing R 2 values of 0.865 and 0.86 for the departing and arriving passengers, respectively. Even though Iraq's unstable political and economic situation led to the interaction between the different demand drivers, external factors have a bigger effect on the country's need for air travel, causing demand shocks that take a long time to recover from.
International journal of electrical and computer engineering systems
Predicting conceptual costs is among the essential criteria in project decision-making at the ear... more Predicting conceptual costs is among the essential criteria in project decision-making at the early stages of civil engineering disciplines. The cost estimation model availability that may help in the early stages of a project could be incredibly advantageous in respect of cost alternatives and more extraordinary cost-effective solutions periodically. There is a lack of case datasets. Most of the proposed dataset was inefficient. This study offers a new data set that includes the elements of road construction and economic advantages in the year of project construction. Real project data for rural roads in the State of Iraq / Diyala Governorate for the years 2012 to 2021 have use to train a predictive model with a high rate of accuracy based on machine learning (ML) methods. Ridge and Least Absolute Shrinkage and Selection Operator (LASSO) Regressions, K Nearest Neighbors (k-NN), and Random Forest (RF) algorithms have employ to create models for estimating road construction costs bas...
Journal of Engineering and Sustainable Development, Mar 1, 2023
The civil aviation demand forecast is a carefully formed perspective for airport system activitie... more The civil aviation demand forecast is a carefully formed perspective for airport system activities. Its main use is to predict possible needs for the planning and financial management processes for air carriers and civil aviation authorities. It is vital to conduct frequent analyses and projections of demand in order to meet their customers' expectations by balancing supply and demand and staying abreast of the ever-changing aviation industry. The purpose of this paper is to establish a mathematical relationship between the socioeconomic explanatory factors such as (population, Gross Domestic Product (GDP), consumption expenditure, rate of exchange, industry, imports, and exports) and activities (passenger movements and aircraft operations) at Baghdad International Airport in order to develop an econometric model. The required data had been collected for the past ten years. Eight models were developed depending on one or more of the explanatory variables using SPSS software, and they were then subjected to cross-comparison to see which model was more robust. According to the findings of the statistics, the gross domestic product, population size, and consumption expenditure are the most appropriate explanatory variables that have a significant impact on these activities, where they had a high R2 and F-statistics value equal to 90% and 73.442, respectively, for the model of air passengers and GDP and 90% and 48.737 for the model of flight operations and GDP.
International journal of electrical and computer engineering systems, Dec 21, 2022
Predicting conceptual costs is among the essential criteria in project decision-making at the ear... more Predicting conceptual costs is among the essential criteria in project decision-making at the early stages of civil engineering disciplines. The cost estimation model availability that may help in the early stages of a project could be incredibly advantageous in respect of cost alternatives and more extraordinary cost-effective solutions periodically. There is a lack of case datasets. Most of the proposed dataset was inefficient. This study offers a new data set that includes the elements of road construction and economic advantages in the year of project construction. Real project data for rural roads in the State of Iraq / Diyala Governorate for the years 2012 to 2021 have use to train a predictive model with a high rate of accuracy based on machine learning (ML) methods. Ridge and Least Absolute Shrinkage and Selection Operator (LASSO) Regressions, K Nearest Neighbors (k-NN), and Random Forest (RF) algorithms have employ to create models for estimating road construction costs based on real-world data. The Root Mean Square Error (RMSE), Mean Absolute Percentage Error (MAPE), and R-squared (R2) coefficient of determination are utilize to assess the models' performance. The analysis indicated that the RR is the best model for road construction costs, with results R2 = 1.0, MAPE =0.00, and RMSE=0.00. The results showed that the cost estimates were accurate and aligned with the project bids.
Mathematical modelling of engineering problems, Dec 13, 2022
The aviation authorities have long been impacted by fluctuations in demand, which are often cause... more The aviation authorities have long been impacted by fluctuations in demand, which are often caused by the aviation industry's cyclical nature. It is affected mainly by many endogenous or exogenous variables. Despite that, the airport authorities and air carrier management make significant efforts to deal with fluctuating demand. This paper analyzed the factors influencing demand at Baghdad International Airport, based on the pertinent local socioeconomic data such as "population size," "GDP," and "terrorism effect," as well as system-based factors related to aviation activities and airport characteristics for the past ten years, to develop a system dynamics simulation model by which the causes of fluctuation are highlighted in order to predict the magnitude and timing of the increment or decline in an offer to minimize losses to all parties in the airport system. The simulation results demonstrated very high goodness of fit with the actual data, producing R 2 values of 0.865 and 0.86 for the departing and arriving passengers, respectively. Even though Iraq's unstable political and economic situation led to the interaction between the different demand drivers, external factors have a bigger effect on the country's need for air travel, causing demand shocks that take a long time to recover from.
A range of stabilisers for poor quality subgrade soils have been developed to promote road constr... more A range of stabilisers for poor quality subgrade soils have been developed to promote road constructions. Many of them are becoming more popular depending on their effectiveness. The purpose behind this research is to identify the relative efficacy of many physical and chemical stabilisation techniques for enhancing the properties of three types of local Iraqi subgrade soils. The comparison of the samples is based on the CBR tests. The AASHTO (1993) flexible pavement design was used to compute the pavement thickness requirements. The soil samples A, B and C have a natural CBR values of 3.8, 3.9 and 4, respectively, on which the physical stabilisers of Powdered rock (PR), grained recycled concrete (GRC), and recycled crumb rubber grains (CR) were employed, while Quicklime (QL) and activated fly ash (AFA) were both utilised as chemical stabilisers. The stabilisation with 15 % of AFA proved to be the most applicable method for soil types A and B for reducing the pavement thickness requirements by 51 % and 32 %, respectively, with a reasonable financial feasibility for both. The same feasibility is proven when stabilising soil type C with 15 % of GRC, which reduces the pavement thickness by 25.7 %.
Many cities in Diyala governorate are su ering from tra c congestion due to high percentage of th... more Many cities in Diyala governorate are su ering from tra c congestion due to high percentage of through tra c. One of the most applicable solutions to such problem is the construction of ring road by which the through tra c is avoided. In this research, Baqubah city is subjected to economic analyses in order to determine whether the establishment of a peripheral ring road to downgrade the tra c congestion in the city center would be economically feasible. e planned road is divided into three segments linking the three major entries to the city. e rst segment is already existing, while the second and third segments are following a predetermined orbital route that has not been utilized yet. Hence, the rst segment is not considered in the economic analyses, which included the second and third. e tra c data was collected for all entries, and then the fractions of tra c that expected to utilize the new ring road were estimated and projected for the design lifetime of the road taken as 20 years after two years of design and construction. e suggested road was proved pro table by the use of two economic parameters: the rst is the bene t cost ratio, which returned the values of 7.44 and 5.92, for the second and third segments, respectively. e net present value calculations revealed the values of $50,399,966 and $43,991,883 for the second and third segments, respectively.
Periodicals of Engineering and Natural Sciences (PEN), Mar 13, 2022
Mobility Demand Management initiatives are seen globally as a solution to the elimination of poll... more Mobility Demand Management initiatives are seen globally as a solution to the elimination of pollution and daily effects in off-road regions. In order to allow improvements on attainable comfort, such steps must have an effect. The High Occupancy Driver Carpool Lane is one of the TDM steps. HOV lanes are not utilized, with 81% of HOV locaters resulting streams under1400 vehicles per track during the PM peak hour strategy. This research is fitting in the Pune and Mumbai districts of India. HOV channels bear a 20 percent cap levy, reaching the highest advancement of 1600 Vphpl at 45 mph over the most drastic stream over 2000 Vphpl at 60 mph as a general justification for GP routes. HOV lanes deliver no investment funds for driving time. In general, HOV lanes decrease considerably as the usually helpful pathways are enabled to be clogged. In spite of these discoveries, HOV offices can take on a valuable job in the framework of all-around supervision of the expressway in India. Basically, where there is a meaning, they will be useful.
This study deals with the evaluation of the stabilization of several samples of soft soil with so... more This study deals with the evaluation of the stabilization of several samples of soft soil with some chemical and physical additives. The intention is to amend the weak properties of these soils summarized in low bearing capacity and high settlement. The used stabilizers are quicklime, class F fly ash activated by cement, rock powder, crushed waste concrete, and tire crumb rubber. The paper investigated the effects of these stabilizers by unconfined compression test that considers very effective geotechnical test for measuring the ability of soils to bear structures constructed on them especially when used additives. This test was carried out on three samples of soils. They were classified by (UCSC) as (CL) soft soils. They were also classified by (AASHTO) as (A-7-6), (A-6), and (A-6) are rated as fair to poor subgrades in (AASHTO). The results of (UCS) test for each of the five additives used were compared according to the responding of each soil samples used. The (UCS) test was conducted in this study on sixty samples of soils before and after treatment and under the basics of the Proctor compaction test at optimum moisture content and maximum dry density. The results showed that the rock powder was the most suitable stabilizer that gave best results of improvement reached to 900% at 25% percent by dry weight of soil, crushed waste concrete came after it that gave treatment 683% at 15%, class F fly ash activated by cement followed the two formers which increased strength 533% at 15%, quicklime after that in an amendment 517% at 9% and finally tire crumb rubber that stabilized the soil 500% at 4%. In the literature, these materials founded to be very efficient in the stabilization of soils in their physical and chemical properties like increasing bearing capacity and reducing settlement of soil.
DIYALA JOURNAL OF ENGINEERING SCIENCES, Jun 16, 2021
Gets in the world at this time continued growth and rapid development in the whole aspects of lif... more Gets in the world at this time continued growth and rapid development in the whole aspects of life. The urgent needing accomplished that is in civil engineering demands like the construction of houses, schools, hospitals, roads, and other structures. Because of that and for economic and security reasons; classifying soil and knowing its bearing capacity appeared to be very necessary conditions that offer a large domain of benefits that could not be counted. This study focused on classifying and determining the bearing capacity of some samples of soil that classified as soft soils of Baquba city the center of Diyala governorate in Iraq. Then trying to increase their bearing capacity. The California Bearing Ratio (CBR) was used in the paper to define soil strength because it is considered a force measuring parameter. Five elected physical and chemical treatments were used in predetermined percents taken from the literature and suited the kind of soil. They were quicklime, class F fly ash activated by cement, rock powder, crushed waste concrete, and crumb rubber of tires. The treatment that was the best among the five used methods was by the rock powder that improved CBR value by 570% in soil samples A used.
DIYALA JOURNAL OF ENGINEERING SCIENCES, Dec 1, 2018
Many models were introduced to estimate the roundabout entry capacity from 1980s until now. In th... more Many models were introduced to estimate the roundabout entry capacity from 1980s until now. In the United States, transportation agencies adopted three different models from 1994 until 2010. The Austroads, the UK, and the HCM 2010 methods. In this paper, these three methods were used to analyze the field traffic data of Al-Quds roundabout, located near Baqubah City, simultaneously by utilizing a system dynamics model. The collected data included turning movements, circulating flows, and field calculated entry capacities whenever possible during the observation period which lasted for 14 consecutive hours. A comparison is then conducted on the resulting entry capacities and their variation over time. The results showed that the calculated capacity according to Austroads method is the highest at all times while the UK method was always a little lower and the HCM 2010 method was always the least on all entries. The UK method capacity estimates were the closest to the field measured capacities for they returned the least RMSE on all entries. Field capacities showed some tendency towards the Austroads results in the north and south bound entries which carry about 66% of the total traffic. While, field capacities showed more proximity towards the HCM capacity results in the east and the west bound entries which carry 34% of the total traffic.
DIYALA JOURNAL OF ENGINEERING SCIENCES, Dec 1, 2016
In airport planning process, there is always a crucial need for good and reliable air traffic dem... more In airport planning process, there is always a crucial need for good and reliable air traffic demand estimate. It is equally important for airport authorities and airline carriers, for in the case of under estimated demand, there would be frequent congestions and delays. Conversely; overestimates would lead to unjustified expenditure which may lead to financial problems to all parties. The accurate and reliable models are not highly sophisticated in nature. In this paper, two econometric models were developed to forecast the passenger enplanements in two of the busiest airports in the United States of America. Many national and local socioeconomic variables were analyzed to come up with simple, yet accurate models. It was found that the total aggregate variables including per capita gross domestic production and population, have more influence on demand in the Hartsfield-Jackson Atlanta International Airport than the local variables, while the same factors, but in their regional scale, proofed to be more influencing in the case of John F Kennedy International Airport.
International Journal of Design & Nature and Ecodynamics, Apr 27, 2022
The complex nature of urban growth in cities whose population is exponentially increasing require... more The complex nature of urban growth in cities whose population is exponentially increasing requires a comprehensive understanding to create a precise and descriptive modelling. In order to identify the main factors that influence the behavior of such complex growth and consequently recognize the most applicable future projection to the growth in each urban category, a system dynamics model was developed in which all pertinent variables are incorporated. This model was proven to be capable of simulating the urban growth in Baquba city for some six decades from 1957 to 2017. The simulation results showed very high goodness of fit with the historical records with an R2 ranging between 0.987 and 0.997 proving the validity and applicability of the model. The interaction between various urban categories showed that the road network area was negatively influenced mainly by the rapid growth of residential and public areas. The future projections of this model to the target year of 2035 showed that the residential, public, commercial and industrial categories are increasing by; 55%, 84%, 40%, and 19% respectively. The road area has also increased by 19% in the same projection gaining more expansion than what it got in the last three decades prior to 2017.
International Journal of Design & Nature and Ecodynamics, Oct 29, 2021
With the growing demand for air transportation and limited capacity at Baghdad International airp... more With the growing demand for air transportation and limited capacity at Baghdad International airport (BIAP), there is a need to increase the capacity of airport systems in the middle district of Iraq. The increased use of secondary airports has been and is expected to be one of the key mechanisms by which future demand is met in congested metropolitan areas. This paper analyzed the factors influencing the emergence of secondary airports in the Iraqi middle district and the dynamics of multi-airport systems. A system dynamics model was developed to simulate the relationship between the core airport in Baghdad and three potential secondary airports, one in each adjacent governorate. The model takes under consideration such characteristics as; capacity, location, proximity to populated communities, and ground transportation services for each airport. the main outcomes of this model are; the passenger's persuasion in an airport, which reflects their propensity to use this particular airport, and the predicted number of annual passengers in each airport. The system dynamics model was consulted twice. The outcomes of the first run facilitated the economic analyses of the secondary airports on which the sequence of the airports emergence was determined, and it also showed that the new airport feasibility is highly affected by the location, due to the influence on the road user cost for passengers, in addition to the capital expenses. The second run of the model helped in predicting the time schedule and interval between an airport emergence and the other. If the new airports have an equal capacity of one million passenger per year, the expected timing for the emergence is in 2023, 2027, and 2032 for the airports in Balad, Habbaniyah, and Baquba respectively.
DIYALA JOURNAL OF ENGINEERING SCIENCES, Jun 16, 2021
Variation Orders is often a reason for construction projects exceeding projects budget and delays... more Variation Orders is often a reason for construction projects exceeding projects budget and delays; it is a global problem, particularly intensive in the case of a recession of the local economy and stagnation. In Iraq, all the projects have delays in completion, and the cost affects because of the variation orders, which are not well managed. The objective of this study was to identify the key causes responsible for the variation order in construction projects in Iraq using the system dynamic. System's dynamics is the discipline of academics and rooted initially been in management and the engineering sciences. The data relating to the performance of construction projects from 27 projects adopted by Diyala University were collected. Personal interviews and questionnaires survey to the selected projects of specialized engineers were done. The results revealed that the size of variation orders in Iraqi construction projects was high, and 13 key causative factors led to variation orders. The variation in cost was the most influential factor effecting the construction project in Iraq. When variation orders in a cost increased, the owner's opinion decreased. When the external factors increased, cost variation orders increased. It was concluded that minimizing the variation orders was very important to realize the cost in the construction projects. Therefore, the authority management and project managers must make a plan to address these key causes in future projects to ensure their success.
Journal of Engineering and Sustainable Development
The civil aviation demand forecast is a carefully formed perspective for airport system activitie... more The civil aviation demand forecast is a carefully formed perspective for airport system activities. Its main use is to predict possible needs for the planning and financial management processes for air carriers and civil aviation authorities. It is vital to conduct frequent analyses and projections of demand in order to meet their customers' expectations by balancing supply and demand and staying abreast of the ever-changing aviation industry. The purpose of this paper is to establish a mathematical relationship between the socioeconomic explanatory factors such as (population, Gross Domestic Product (GDP), consumption expenditure, rate of exchange, industry, imports, and exports) and activities (passenger movements and aircraft operations) at Baghdad International Airport in order to develop an econometric model. The required data had been collected for the past ten years. Eight models were developed depending on one or more of the explanatory variables using SPSS software, and...
Mathematical modelling of engineering problems, Dec 13, 2022
The aviation authorities have long been impacted by fluctuations in demand, which are often cause... more The aviation authorities have long been impacted by fluctuations in demand, which are often caused by the aviation industry's cyclical nature. It is affected mainly by many endogenous or exogenous variables. Despite that, the airport authorities and air carrier management make significant efforts to deal with fluctuating demand. This paper analyzed the factors influencing demand at Baghdad International Airport, based on the pertinent local socioeconomic data such as "population size," "GDP," and "terrorism effect," as well as system-based factors related to aviation activities and airport characteristics for the past ten years, to develop a system dynamics simulation model by which the causes of fluctuation are highlighted in order to predict the magnitude and timing of the increment or decline in an offer to minimize losses to all parties in the airport system. The simulation results demonstrated very high goodness of fit with the actual data, producing R 2 values of 0.865 and 0.86 for the departing and arriving passengers, respectively. Even though Iraq's unstable political and economic situation led to the interaction between the different demand drivers, external factors have a bigger effect on the country's need for air travel, causing demand shocks that take a long time to recover from.
International journal of electrical and computer engineering systems
Predicting conceptual costs is among the essential criteria in project decision-making at the ear... more Predicting conceptual costs is among the essential criteria in project decision-making at the early stages of civil engineering disciplines. The cost estimation model availability that may help in the early stages of a project could be incredibly advantageous in respect of cost alternatives and more extraordinary cost-effective solutions periodically. There is a lack of case datasets. Most of the proposed dataset was inefficient. This study offers a new data set that includes the elements of road construction and economic advantages in the year of project construction. Real project data for rural roads in the State of Iraq / Diyala Governorate for the years 2012 to 2021 have use to train a predictive model with a high rate of accuracy based on machine learning (ML) methods. Ridge and Least Absolute Shrinkage and Selection Operator (LASSO) Regressions, K Nearest Neighbors (k-NN), and Random Forest (RF) algorithms have employ to create models for estimating road construction costs bas...
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Papers by Raquim Zehawi