Road and Transportation Engineering

Permanent URI for this collection

http://etd.aau.edu.et/handle/12345678/137

Browse

Browsing Road and Transportation Engineering by Author "Abebe, Dinku (Prof.)"

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Asphalt Road Pavement Rehabilitation and Maintenance Case Study in Addis Ababa City Roads Authority
    (Addis Ababa University, 2016-03) Girmay, Temesgen; Abebe, Dinku (Prof.)
    Addis Ababa City Roads Authority representing the Addis Ababa City Administration manages the entire city roads. Currently it is engaged in increasing Addis Ababa city road coverage to reach 25% within 2012 E.C. However, literatures indicate that most of the city roads severely suffering from lack of proper maintenance. Hence, identifying critical problems can be input towards improving road maintenance and rehabilitation activities of the City roads. After detail review of scientific literature and international experience in managing asphalt maintenance, based on pavement evaluation, maintenance and pavement management system questionnaires was developed and interview was conducted. Through interview and questionnaire survey of professionals; the present maintenance and rehabilitation practice of AACRA was assessed. Responses were graded by average index method. In conclusion, the finding of this study implies that Addis Ababa City Roads Authority doesn‟t conduct adequate pavement condition evaluation that can be sound input for recommending maintenance options and the maintenance work is limited to overlay and pouching and performing maintenance without adequately defining the route cause of distress, moreover this study identifies the greatest challenge for road rehabilitation and maintenance in AACRA is the absence of well established pavement management system. The study recommended that AACRA shall asses and apply alternative pavement evaluation and maintenance methods. Moreover, AACRA has to establish pavement management system to manage maintenance activities for better and optimum utilization of resource. Further research is also recommended which includes development of pavement management system and pavement treatment selection alternatives for Addis Ababa City Roads Authority. Key Words: pavement evaluation, pavement maintenance, pavement management
  • No Thumbnail Available
    Item
    Causes and Effects of Variation Orders in Road Construction Projects: The Case of National Works Contract Administered by Addis Ababa City Roads Authority.
    (2015-04) Zewdu, Tewodros; Abebe, Dinku (Prof.)
    This thesis assesses variation orders in national works contract of Addis Ababa City Road projects by investigating the predominant causes, studying their effects on the project, identifying initiating parties, and suggesting controlling remedies to alleviate such related problems. The main purpose of this study was to study, identify and mitigate those common and frequent variation orders encountered in Addis Ababa City Road projects which are being reflected in the projects delay, cost overrun, and disputes. In order to obtain the view of many role players such as employer, consultants and contractors in the industry on these phenomena a concept study was developed through literature survey. Following a survey was conducted and analyzed using a questionnaire and desk study assessment. Based on the analyzed data the most predominant causes, origin agent, consequential effects were identified and controlling methods were also proposed. The results revealed that inadequate design, error and omission in design and ambiguous design were the main causes of consultant originated variations while Right of way (access to site) problem, change of plans or scope and inadequate objectives were the main causes of client originated variations. The study further revealed that in most situations variations have resulted in cost overrun, time overrun and disputes. The finding indicated that consultant is the major source of variation orders. It is also recognized that the issue of variation order in road construction projects of Addis Ababa City is serious and could be managed by applying proper construction management tools at design, construction and design-construction interface stages. Finally remedial recommendations are forwarded based on the findings of the results. Key words: cause, change, cost overrun, effect, time overrun, origin agent, variation, variation order.
  • No Thumbnail Available
    Item
    Study on Cost Related Claim Practice in Federal Road Projects; Focused on Local Contractors
    (Addis Ababa University, 2015-06) Gezahegne, Derege; Abebe, Dinku (Prof.)
    The Government of Ethiopia formulated the Road Sector Development Program (RSDP) in 1997, and till the end of 2013, local Contractors participation was 46% with amount of ETB 48,416.79 million, contracted for 278 projects, which is 75% of the floated bid. In a competitive atmosphere of tendering, little or no margins are left for future unknowns in a long and complex period of construction wherein the rates and prices shall be based on certain assumptions and any change between what was assumed and what actually happens may form a seed for a claim, and contracts have provision for monetary compensation to mitigate its effect. In relation, this research aims to study the causes of the cost claim events, conduct an assessment of local contractors cost claim management and to assess mitigation measures to minimize the impacts on local contractors capacity participated in the Ethiopian federal road projects. The research revealed that local contractors have poor contract management practice, especially in cost claim submission despite there are events that entitle them monetary compensation under the FIDIC 1987 conditions of contract. The study also indicated that all parties involved in the construction of the road projects have role for the poor achievement of monetary compensation to local contractors; however, a large portion of the contribution is the negative attitude to cost claim determination in the construction industry, poor contract management skills, unfair determination by the consultants and DRE and Employer’s interference in the determination of claims as identified in the research. Thus, it is very important that all parties involved in road projects improve their contract management practices, especially local contractors need to enhance their awareness of contract/claim management to protect their company from cumulative and catastrophe effect of the poor claim management. The Employer shall also play his role for creating positive awareness towards claim management as poor capacity of contractors and industry will be reflected in the success if the road sector development programmes. Keywords: Claim, Client, Contract, Consultant, Contractor, Cost Claim, Dispute, Dispute Review Expert