Road and Transportation Engineering

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Analysis of Road Traffic Violations in Addis Ababa City (The cause of Arada sub-city)
(Addis Ababa University, 2018-10) Gadisa, Layo; Getu, Segni (PhD)
Road traffic injury death rates are highest in the African region. Violation of traffic rules, which is a human factor, is an important factor behind traffic crashes and many lives could be saved if all drivers complied with the rules and regulations of road. Other than piece of reports from traffic police, very few is known about magnitude, trends and characteristics of traffic offences in Addis Ababa City. In addition, almost no literatures exists on differences in traffic offences by driver and vehicle characteristics in Addis Ababa city. The objective of this research is to characterize and identify most common traffic offences, trends and magnitudes of traffic offences in Arada sub city over 3 years. Further, this study also investigates differences in traffic offences by drivers and vehicle characteristics. Finally, this study finds attitudes of traffic offenders towards unsafe driving behaviors. Methodology-To achieve the objectives of this research two methods were followed. The first method was secondary traffic offence data collection from Arada sub city over (2007E.C2010E.C) and analyzed. The second method was through questionnaires results from 385 traffic offenders at sub city traffic police department who come to take back their driving license and vehicle plate after paying traffic offence fines. Questions containing traffic offender and vehicle characteristics, history on traffic crashes and frequency of traffic offences for selected traffic offence types and attitudes towards unsafe driving behaviors were prepared. These collected data were analyzed by Excel and SPSS; Independent t-test, one-way ANOVA test, Chi-square, Descriptive and frequencies were used. Results-Over all, 154436 traffic offences registered, 95.6% occurred by male. It showed an increase of 8.3% and 13.04% in 2008 E.C and 2009 E.C respectively. But, the rate is decreasing for female averagely by 2.4% and increasing for male averagely by 13.7%. The most common traffic offences were traffic flow obstruction (12.9%), disrespecting prohibiting signs (11.3%), parking of motor vehicles on prohibited areas (8.5%), overloading (8.2%) and using mobile phone while driving (7.8%). Youth groups (18-30 years) are the most traffic offenders than any other age category and drivers older than 50 were the second traffic offenders as compared to licensed driver population in the city. Drivers with license level 4, 5 and license level 6 (with old licensing system) were more involved in traffic offences than others as compared to their corresponding license population in the city. Code 1, 5 and others (T, CD, UN, ET and police) vehicles showed higher involvement in risk factors of road traffic crashes. Further, vehicles coded 1 showed higher involvement in total traffic offences. Results of Chi-square showed that there is an association of driver and vehicle characteristics and crash involvements. Traffic offenders with degree and above education level, 11-15 years of driving experience, low income, code 3, new vehicles with (0-5 service year) and privately owned vehicles showed higher involvement in traffic crashes than others . Results showed that male (p-value=0.002), in-friendship or cohabited (p-value=0.0022), 3-5 years of driving experience (p-value=0.036), taxis (p-value=0.036), medium income (p-value=0.001) traffic offenders showed higher significant score in speeding at 5%. In case of red-light running, traffic offenders of 24-29 years old, (p-value=0.012), private workers, (p-value=0.003), vehicle service year, 6-10 years (p-value=0.001) showed significant higher score. Finally, respondents have negative attitudes towards unsafe driving behaviors but they still don’t completely translate into positive behaviors. Conclusions- It can be concluded that male, 18-30 years, vehicles coded-1 (taxis), coded-3 (commercial vehicles) and coded-5, and drivers with license level-4, license level-5 and license level-6 were highly connected to traffic offences. In addition, young age (24-29years), new vehicles (0-5years), single and private workers, higher education levels (degree and above), experienced drivers, Buses and private cars also showed higher connection with number of traffic offences and crash involvements. More stringent effort and proper interventions should be done towards these groups and the most common traffic
Analysis of Traffic Congestion and its Economic Cost in Addis Ababa A Case Study of Meskel Square to Kality Interchange
(Addis Ababa University, 2017-03) Kefyalew, Tadele; Bikila, Teklu (PhD)
Cities in the world have faced many challenges like traffic congestion, air pollution, noise pollution and accidents. These challenges especially traffic congestion, is however, expected to aggravate in the nearest future. Due to congestion commuters travel time and vehicle operating costs increase with fuel consumption and emission rates increase with pollutants increases. Following its economic development, Addis Abba has faced traffic congestion problems which cause chronic problems to both the road users and non-users. This paper mainly focuses on traffic congestion analysis and its economic cost by addressing traffic congestion causes, effects, patters and especially its economic cost on the North-South corridor of Addis Ababa. In order to analyze traffic congestion, travel time approach was used whereas analysis of level of service analysis was made using SIDRA intersection based on delay. Afterward, traffic cost is calculated considering delay to passenger vehicles which includes operating costs, extra fuel wasted due to congestion, delay to truck vehicles including operating cost, extra fuel wasted due to congestion by truck, business cost and finally environmental cost of traffic congestion. Then finally, measures to mitigate traffic congestion are recommended based on questionnaire and field visit study. Based on the analysis, it was found that total congestion cost including delay, wasted fuel and operating cost of passenger vehicles and truck vehicles at each road segments on average is about Birr 53.2 million per year. In addition, congestion has costs on the environment and results show that when traffic congestion increases fuel consumption and emission of pollutants increase. From the different traffic congestion measures, improving current light rail transit is the most important since by improving the current status of light rail transit, on the average Birr 25.5 million per year cost of congestion is saved and 11,281.20 kg of CO2 emission is reduced per each road segment.
Development of Modal Choice Model For HomeBased Work Trips-The Case of Jemo Area Residents In Addis Ababa A Thesis in Road and Transport Engineering
(AAU, 2018-08) Firdews, Ali; Bikila, Teklu (PhD)
Addis Ababa is one of the cities that are plagued by a continuous increase in traffic congestion which resulted in longer travel times, increased accidents, more fuel consumption, and deterioration in air quality. Providing and improving urban public transport service is highly important in mitigating these challenges as well as creating sustainable transport systems. The corridor from Jemo to Mexico is one of the most congested corridors in the city and the trips in the morning peak hour are mostly home-based work trips. The study of modal choice behavior of residents traveling to work will guide policy makers to improve the service quality of public transportation systems in a way the majority of the commuters will use them. Discrete choice models can be used to analyze and predict a decision maker’s choice of one alternative from a set of alternatives. This study aims to contribute for the improvement of the service quality of public transport systems in the city by determining the basic factors that affect the preference of modes and how each factor affect the mode choice of trip makers to travel to work place. 475 questionnaires were collected in which 4/5 th of the data were used for calibration and 1/5 th for validation of the revealed and stated preference models. The collected data of variables related to the trip maker and characteristics of the mode are fitted in special type of multinomial logit model known as conditional logit model using SPSS. Revealed preference model was developed for preferences among large bus, minibus (taxi) and private cars. Whereas the stated preference model was developed for preferences among the existing modes (large bus, minibus (taxi) and private car) and the BRT system. The developed models for the revealed preference survey proved that the total travel time and total travel cost of the transport modes are the primary factors that statistically significantly affect in addition to car ownership, time of leaving home and education level interaction variable with taxi. The stated preference models indicated that the preference towards the BRT increases with the decrease in total travel cost, in-vehicle travel time and out of vehicle travel time. The models are validated to be capable of predicting 80% and 92% of the preference of trip makers among the available revealed and stated modes, respectively.
Evaluating the Economic Impact of Bus Stop design in Addis Ababa City
(Addis Ababa University, 2018-04) Eyob, Hilemichael; Alemayehu, Ambo (PhD)
Public bus transportation system plays a key role in shaping transportation structure of large and fast-growing cities most importantly in combating air pollution and traffic congestion compared to small cars. As a result; most urban transportation needs are served with public bus transportation which is also one of the most important modes of transportation in Ethiopia in general and in Addis Ababa in particular by providing intra-city transportation services with bus stations. Despite, these scattered contact points provide access, decision on how many bus stops to provide along service routes significantly influence financial & ridership performance of the agency and the community at large. For this reason evaluation of economic impacts is essential in order to have a sustainable transport system, which can be performed from efficiency and equity objectives, where “Efficiency” assumes that policies should strive to maximize social welfare while “Equity” is a highly subjective concept which assumes policies should ensure benefits and costs are spread in a fair way. Unfortunately, economic impacts of bus stop designs have not been seriously dealt with in Ethiopia; hence the purpose of this paper is to successfully evaluate the economic impacts of bus stop for selected routes. In line with this, to evaluate the perceived compromise between equity and efficiency with in local context; the impact on the primary recipients of public transit (i.e. users), nonusers to ensure equity of the system benefits and costs to the society at large and agency costs in the course of service are considered. As doing so the geographical scope of evaluation is limited to three major routes of ACBSE with fixed stop patterns whereas the temporal scope of impacts is limited to short term to minimize the effects of influencing factors. Taking bus stations as a point of interest two cases are defined: (1) Base line scenario the existing spatial distribution of bus stops and (2) Alternative scenario: bus stop location‟s that can balance of possible concerns and feasible courses of action are modelled by transit expert‟s opinion through AHP-derived weights and DCPMP to optimize bus stops in order to promote greater geographic coverage with a limit in number of stops in ArcGIS. To further understand what costs and benefits that could be related with base line scenario in the absence of change against the costs and benefits predicted in the alternative scenario in terms of service coverage, environmental effects and road user costs are examined. These key indicators used are further boiled down to reflect the magnitude and values of monetary and non-monetary costs and benefits economic effects (operating cost reductions), environmental affects, (emission reductions) and service coverage. Subsequently, the research used two different questionnaire surveys to capture the general public and transport experts opinion which are analysed in SPSS, ArcGIS for inventory of existing stops, determine accessibility & conduct suitability analysis, HDM4 to quantify the vehicle operating costs and resulting emission, online tools to calculate the VOC during idling of vehicles, IPCC guideline to calculate the carbon footprint in idling and route level fare recovery ratio to gauge the efficiency of ACBSE. The said impacts are brought together to demonstrate the overall benefits, costs and net benefits. Results in route of interest provide positive evidence on an alternative scenario that proposed change of bus stops‟ (about 8% of current stops) could increase agency direct operating costs by 4.89% as compared to baseline. Besides, vehicle fleet and idle exhaust pipe CO2 emissions decline by 12.3% from base case. Surprisingly, the gain in coverage due to elimination and addition of bus stops is large (7%) of the total population of Addis Ababa city when compared to the baseline. On the other hand, the total land required for clearing polluted air by the biosphere using tree plantation slightly decreased by 0.19% while the total sapling, land, agency management and conservation work cost for 25 years maintained by 0.19% from 621,832 Birr of baseline. While this is the case assessment on financial and ridership efficiency indicated ACBSE is recovering the direct operating cost during 2016/2017-2017-2018 from ticket sales in the case study routes. Summing up by comparing the present values of net benefit and costs the proposed alternative has greater economic worth and ACBSE service provided is moderately equitable but not efficient.
Evaluating the Sustainability of Urban Mobility And Traffic Growth in City of Addis Ababa
(Addis Ababa University, 2019-05) Yodit, Dejene; Bikila, Teklu (PhD)
t has been long since mobility became a major issue in Addis Ababa following the enormous horizontal expansion of the city boundaries because of the rapid population and income growth. The current transportation problem in Addis Ababa is at its boiling point, and worsening by the day despite the government‘s attempt to address it. As transport system is an important part of a city, success in insuring mobility can even be an indication of how well the city really is organized. Failure to provide well-functioning transport system causes growing social, economic as well as environmental problems. Spatial sprawl, infrastructural development and increasing vehicular number are concurrent trends that need coordination among actors and policies for sustainable development. Although there are studies conducted to understand and solve the problems related to motorized transport in the city, most of them focus on the conventional approach of improving the physical infrastructure of the transport sector to enhance the service provision by constructing highways, extending road networks and increasing the number of fleet. Measures that differ from the ones with the conventional focus of congestion and mobility should be assed. The general objective of the study is to evaluate sustainability of transport system in Addis. Although Sustainability is difficult to be measured directly, it can be evaluated through a system of parameters and indicators constitute part of this process. A procedural framework was developed to select potential local indicators for the current work. Data were collected using different techniques at various stages. Existing database, unprocessed data from surveys and processed data from spatial studies were among the sources used for data gathering. Indicator parameters are obtained by means of formula calculation, extraction from previous studies or other methods. The score of indicators are then calculated based on the parameter value. In line with the results from the analysis, the sustainability of city transport system scores 2.69 out of 5 suggesting weak sustainable mobility conditions. The results of this application highlight the priorities for the improvement of city‘s sustainable mobility conditions as presented using a spider chart, which gives the disaggregated overview of the mobility performance. Consequently, a shift towards more sustainable modes of transport like public and non-motorized transport is needed. The trend analysis on vehicle growth also confirmed lack of attention for these modes. Most of the trends indicate that the current traffic growth is unsustainable.
Examination of Selected Public Transportation Modes in Addis Ababa City
(Addis Ababa University, 2020-03) Endashu, Tekalign; Getu, Segni (PhD)
Addis Ababa is the capital city of Ethiopia with population of 5 million and the fastest growing economy in Africa. However, urban transportation system is one of emerging problem in Addis Ababa. The increasing public transportation demand, mobility, ridership, accessibility, capacity, congestion, affordability, health and safety problems need urgent solution. Currently the city’s administration is on the way to introduce public transport like Bus rapid transit. Even though the Light Rail Transit has operational, maintenance, accessibility problems it caters more than 120,000 riders per day, on average. However, quantitative and qualitative benefits and costs are not well studied from the city`s context. The general objective of this study is to examine Addis Ababa Light Rail Transit and Bus Rapid Transit systems against multifaceted criteria. The first objective is the comparison of life cycle cost-benefit analysis among AA LRT and AA BRT. The second objective is to examine the effect of AA LRT infrastructure`s on the surrounding built-up activities using a selected line from Megenagna to Sealite-Mihiret. The multifaceted LCCA is conducted for 30 years and using a discount rate of 10.23% to convert costs and benefits into present values (2019 USD. The result shows that that the NPV of AA BRT with trolley is 23,340,539.98USD/km which is greater than the other two alternatives. AA LRT has 12,752,547.77USD/km and AA BRT with diesel buses has 7,537,666.36USD/KM of NPV. The Benefit to Cost Ratio (BCR) of AA BRT is 2 and 1.5 per km for trolley and diesel buses which is higher than that of the LRT with 1.24 per km. Sensitivity analysis is also conducted by increasing selected costs and decreasing selected benefits resulting in a decreased value of NPV which is positive and BCR which is greater than one. To attain the second objective, 384 questionnaires were distributed for residents located around 500m distance from the both sides of the selected LRT corridor. The result shows for more than 71% and 68% of the respondents, there is a longer distance and time respectively whether they use walking and/or other public transportation modes after LRT is constructed. 82% of the residents reacted that the infrastructure increases the width of the roadway which inhibits their crossing movement and decreased their neighborhood interaction. Finally it is concluded that the AA BRT with trolley buses the most cost effective option. But by enhancing the annual benefits of the MRTs through simple cost effective modifications to attract more passengers, their introduction and future expansion is more recommendable according to this study`s result. Additional recommendations from the result of sensitivity analysis proven that the agencies that manage these mass rapid transit systems should consider adding up more benefit categories and more benefit amounts to increase viability, efficiency, cost effectiveness and affordability. On the other hand, the result from the estimation of AALRT`s impact on non-users shows that the infrastructure has negative impact on them. But this can be solved by conducting proper planning through assessing its effect on surrounding users before expanding it. Evaluating impacts only on the direct users of the mode and the agency is not a correct way of assessment. So, before implementation of any mass rapid transit systems within the city, it is recommendable to also examine their monetary and non-monetary impacts on external and internal users in order to reduce or alleviate the corresponding negative effects. It should be encouraged to attain a sustainable development in all public transportation modes in general. Therefore, this study can be used as an input for Policy and planning decisions which often involve economic analysis to determine whether a particular Mass Rapid Transit option is cost-effective or efficient, viable and which option provides the greatest overall benefits.
Investigation and Modeling of Road Traffic Accidents at Five-Legged Roundabouts in Addis Ababa City
(Addis Ababa University, 2018-06) Tsegay, Gebremicheal; Bikila, Teklu (PhD)
In present time, road traffic accident is becoming among the most threatening concerns that prominently hamper the social, economic, and environmental conditions in Ethiopia and Africa at large. So far, previous crash prediction models at roundabout intersections have focused predominantly on the customary three-legged and four-legged roundabout types. This study however aimed at investigating and modeling road traffic Accidents/crashes at five-legged roundabouts in Addis Ababa City, Ethiopia. To this effect, the study collected necessary quantitative and qualitative data from both primary and secondary data sources. The data were analyzed through descriptive and inferential statistical approaches. APMs were developed using the Poisson and Negative Binomial Regression Models for the Severe-crashes (personal injuries & fatal crashes), and property damages only (non-injury) crashes, respectively. Accordingly, the study revealed that the peak hour vehicle volume entering the roundabout through the major road, ratio of diameter of the inscribed circle to diameter of the central island, and entry half road way width have positive associations with the frequency and occurrences of RTAs –particularly the PDO crashes at roundabouts. Furthermore, the study finally forwarded that reducing the entry half road width on the minor leg; constructing and maintaining bypass/detour roads; implementing advanced traffic management schemes; and decreasing the circulatory roadway width were important points that should be taken in to considerations so as to decrease crashes by decreasing the peak hour flows and optimizing the circulatory road way width to increase diameter of the central island. It has to be noted that special care should be required to consider flow parameters such as level of service and capacity situations.
Investigation of Pedestrian Safety Problems and Their Remedial Solutions in Addis Ababa: The Case of Kirkos Sub City
(Addis Ababa University, 2015-12) Abiy, Eguale; Bikila, Teklu (PhD)
The road traffic crash statistics of Addis Ababa shows pedestrian injuries have the highest share among all road users.This research aims to investigate current pedestrian safety problems in Addis Ababa and tries to identify factors influencing it.The study area, Addis Ababa has ten sub cities where Kirkos sub city ranks first with the highest total road traffic crashes.This sub city is selected as a study site and pedestrian-vehicle crash data for three consecutive years were collected. These data were analyzed using odd ratio analysis and logistic regression analysis. Moreover, sample pedestrians and drivers were selected randomly and filled out questionnaire with list of hundred factors related to pedestrian safety in four categories: pedestrian related, driver related, vehicle related and road and environment related; which was analyzed by Likert scale rating and reduced it to top twenty ranked factors.Then these twenty factors; five from each categories were taken and pair wise comparison by senior experts was employed by Analytical Hierarchial Process (AHP) technique. Analyzing these resulted in a rank for each factor with their global weight.The top three are related to driver behavior: alcohol use by drivers (11.55%), driver rush and negligence (6.084%) and improper or erratic lane changing (6.048%).The twenty factors were then grouped to the four categories with their local ranking. In the odd ratio analysis, four hypothesis were tested and only one hypothesis is accepted indicating drivers with experiences of more than 10 years are most responsible to pedestrian serious injury. From the logit model driver-vehicle relationship, junction type, pedestrian age and pedestrian sex are positively associated with pedestrian injuries.Thus in order to take appropriate measures towards pedestrian safety: pedestrian related factors, driver related factors, vehicle related factors and road and environment related factors need to be considered and appropriate measure has to be considered in a systematic way. Rather than a scattered spots approach by a piecemeal basis; a perspective towards looking the urban network of road infrastructure, pedestrian facilities and the urban land use is considered in this research. This research concludes a strategic way has to be followed towards promoting road safety and pedestrian safety in Addis Ababa that would be an area-wide and multi-disciplinary approach, that is, urban safety management.
Optimizing of Freight Transport and City Logistics Activities in Addis Ababa
(AAU, 2011-09) Nebyi, Gebremariam; Girma, Gebresenbet (PhD)
Though goods distribution is an important part of activity in urban life as it plays a vital role in urban economy in terms of income generation and employment opportunities, nowadays urban freight distribution is creating many challenges like environmental pollution, congestion and traffic accident in the growing cities in developing nations. ABSTRACT Thus, this research paper aim is to optimize freight transport and city logistics activities in the city of Addis Ababa so that goods can be distributed to the city center, without jeopardizing the lives of city dwellers, depleting environment and also enabling a good economic efficiency of freight transport and maximized profit for stakeholders. According to the traffic data collected from field survey and the historical traffic data collected from ERA, on average 19,088 and 18,428 freight vehicles per day enter and leave the city of Addis Ababa respectively out of which, 66.6%, 19.6%, 6.59%, 4.33% and 2.93% enters through gate of Debrezeit, Jimma, Gojjam, Debrebrhan and Ambo respectively where, 27.94%, 27.83%, 23.67% and 20.56% were Medium Trucks, Heavy Trucks, Small Trucks and Truck Trailers Respectively and similarly 67.43%, 16.30%, 8.24%, 4.06% and 3.97% exits through the gate of Debrezeit, Jimma, Gojjam, Debrebrhan and Ambo respectively accounting 27.74%, 27.59%, 23.07% and 21.60% Medium Trucks, Heavy Trucks, Small Trucks and Truck Trailers Respectively . Future prospects from the study reveal that freight traffic entering to the city and leaving the city will grow at an average rate of 10.03% and 9.63% respectively and as a result the entering and leaving freight traffic will raise to 90,633 and 86,124 respectively by 2015. Out of the total vehicles driven within the city, only 7.53% were freight transporting vehicles accounting the least share and 36.61% were cars taking the largest share. In view of load factor which is in terms of weight, it was found that due to limited application of city logistics measures within the city freight transporting vehicles operate at an average load factor of 53% which leads to increased transport cost. Within the city more than 146 warehouses and 1 freight terminal are available where 59% of the warehouses are located within the main city center and major sub-centers of the city attracting huge freight vehicles and operating at a poor level of service. Regarding to the terminal delay, it was found that terminals cause vehicles to delay for about 120 days. According to the study, commodity type, season and transparency of the customers, capacity of custom officers and transitors and capacity of the terminal were the basic factors that affect delay of terminals. To minimize the negative impacts, five optimum freight terminal locations were selected with the help of factor rating method and this newly selected terminals are expected to minimize the negative impacts of the freight distribution as they minimize entry of freight vehicles to the city center and terminal delay. It is perceived that, high increase in the road freight transport coupled with the little awareness of city logistics measures and concepts within the city and the country in general are the main reasons that are causing problem within the city. Hence, strengthening freight transport data base management system, creation of awareness regarding the concept of city logistics with its advantages and environmental impacts among stakeholders and further researches on possibility cooperative freight delivery system, coordinated goods movement and investigation of the possibility to use other ports other than port of Djibouti for import and export activities should be the task of researchers and concerned authorities before the problems get worse.
Study on Saturation Flow Rate and its Influencing Factors at Signalized Intersections Under Hetrogenous Traffic Condition (The Case of Addis Ababa)
(Addis Ababa University, 2020-10) Getacher, Negesse; Bikila, Teklu (PhD)
In Addis Ababa signalized intersections are the most important and common bottleneck locations because the functional traffic signals are inadequate to the job of handling current traffic levels and poor traffic management strategies. To mitigate capacity-related problems at signalized intersections appropriate allocation of traffic signal timing and providing effective management of signalized intersections have great importance. The saturation flow is the most important design parameter for traffic signal timing and performance evaluation of signalized intersections. In different cities, various studies have been done to evaluate the saturation flow rate under homogeneous traffic conditions and estimate it only for through movements. However, until now no sufficient study has been conducted on the saturation flow rate at signalized intersections in the case of Addis Ababa for different lane groups under heterogeneous traffic conditions. Therefore the major objective of this research was to determine prevailing Saturation Flow Rate for specific lane groups at signalized intersections during peak hours the case of Addis Ababa, Ethiopia. The lane groups considered were an exclusive left lane, shared left and through lanes, through only lane, and shared through plus right lanes. Using video recording technique data were collected from 24 approaches of six signalized intersections and HCM 2010 standard procedure was followed in the data collection, extraction, and analysis processes. The results of the study indicate that both in the morning and afternoon peak hours the highest mean prevailing saturation flow rate was found for the through lane group, while the lowest was to be determined for the exclusive left lane. Generally, the overall mean prevailing saturation flow rate appropriate for Addis Ababa signalized intersections are 1462 vehicles per hour per lane for exclusive left lane, 1446 vehicles per hour per lane for shared left and through lane, 1542 vehicles per hour per lane for through lane movement and 1492 vehicles per hour per lane for through plus right lane. Those prevailing SFRs can be used as input for planning, design, operation, and analyses of signalized intersections in Addis Ababa. It was determined from ANOVA analysis there was a significant statistical difference between four types of lanes in the morning and afternoon peak hour at 5% significance level. Independent sample t-test shows that there is a statistically significant difference between saturation flow rate values of the lane groups considered in this research.

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