COLLECTIONS

JOURNALS

Documents published in Scipedia

• Cost and Benefit Analysis of Rigid and Flexible Pavement: A Case Study at Chancho –Derba-Becho Road Project

  E. Quezon

  International Journal of Scientific & Engineering Research (2016). Yonas Ketema, Prof. Emer T. Quezon, Getachew Kebede. Cost and Benefit Analysis of Rigid and Flexible Pavement: A Case Study at Chancho –Derba-Becho Road Project. International Journal of Scientific & Engineering Research. 2016; 7(10): 181-188

  
  

  Abstract

  Road construction projects have been implemented all over Ethiopia as part of the national development plan. Roads are one of the country’s basic infrastructural facilities where high amounts of the budget allocated every fiscal year planning period. Since the cost comprises of a large portion of government investment, a careful evaluation of the alternatives is of utmost importance to make the right choice for a particular project. In the history of Ethiopia's road development program, almost all of the road pavements are flexible, and it demands high foreign currency for asphalt material importing from abroad. In addition, flexible pavement needs to be maintained and rehabilitated within a few years after its initial construction. In view of the emerging cement factories and the availability of cement in Ethiopia, it is practical to consider rigid pavement as one of the alternatives. Relative to this, the research project was conducted with the main objective of identifying the cost and benefit of rigid and flexible pavements at the Chancho-Derba-Becho road project, North Showa Zone in Oromia. The research work had been focused on the specific objectives to determine and compare the life cycle costs of rigid and flexible pavements and to investigate all other qualitative merits of rigid and flexible pavement. To achieve these objectives, a review of related literature, design and specifications, observations and investigations of the actual pavement construction projects, evaluation of life cycle costs, the future value of money and present worth calculation were undertaken with an analysis period of 40 years. While the data considered was gathered through investigation at the actual rigid and flexible pavement projects, an examination of specifications, drawings and pavement design, Ethiopian Road Authority manuals, rehabilitation, and maintenance strategy. In this regard, the cost parameters investigated are initial construction cost, maintenance cost, rehabilitation cost, user’s cost, and salvage value, in addition to other qualitative and quantitative data. Based on the results of the research project, it revealed that the initial cost of rigid pavement was almost twice of the flexible pavement, but in the long run, the cost of flexible pavement per kilometer was found out to have 7.9 Million ETB more than the rigid pavement because of the incurring costs of maintenance through its design life. Therefore, it is suggested that Portland Cement Concrete Pavement (PCCP) shall be used in pavement construction to cater to local material requirements. 

  Abstract
  Road construction projects have been implemented all over Ethiopia as part of the national development plan. Roads are one of the country’s basic infrastructural facilities [...]

  • 32
  •  read

• Comparative Study of Labor-Based Method and Machine-Based Method at Rural Road Construction and Maintenance in Jimma Zone, Oromia Region, Ethiopia

  A. Dunffa, E. Quezon, E. Agon

  American Journal of Civil Engineering (2017). Anwar Kassahun Dunffa, Emer Tucay Quezon, Elmer De Castro Agon. Comparative Study of Labor-Based Method and Machine-Based Method at Rural Road Construction and Maintenance in Jimma Zone, Oromia Region, Ethiopia. American Journal of Civil Engineering. Vol. 5, No. 4, 2017, pp. 212-219. doi: 10.11648/j.ajce.20170504.13

  
  

  Abstract

  The construction of physical infrastructure is contributory to poverty alleviation in every country. The road is one of the major components which is very significant in Ethiopia due to the lack of highly developed infrastructure, particularly in the rural road sector. Selection of the appropriate road construction and maintenance methods such as a labor-based method or machine-based method is necessary to be financially viable. Most rural road construction projects usually suffer from the problem of selecting the appropriate technology for the proposed project and implementation of the chosen technology. In Ethiopia, Universal Rural Road Access Program (URRAP) is an employment-intensive program for employment purposes as a first step, out of poverty using labor-based road construction. However, there are problems, constraints, and challenges encountered when implementing labor-based methods leading to enforce the mobilization of machines. The aim of this research study is to carry out the comparative analysis of ongoing and finished rural road projects in Jimma Zone and to establish qualitative and quantitative merit of various technologies used in rural road construction and maintenance. Results showed from financial cost comparison, the labor-based method was 47% cheaper than a machine-based method to carry out the same tasks. On the other hand, the share of unskilled average direct labor cost comprised an astounding 65% more of the total direct cost of a labor-based method. Also, the labor-based method directly employed 300 unskilled laborers per workday for a month to complete a 1.0 km section of a rural road.

  Abstract
  The construction of physical infrastructure is contributory to poverty alleviation in every country. The road is one of the major components which is very significant in Ethiopia [...]

  • 51
  •  read

• Combined Effects of Molasses-Lime Treatment on Poor Quality Natural Gravel Materials Used for Sub-Base and Base Course Construction

  Y. Mamuye, E. Quezon, A. Geremew

  GSJ (Select a year). Yibas Mamuye, Emer Tucay Quezon, Anteneh Geremew. Combined Effects of Molasses-Lime Treatment on Poor Quality Natural Gravel Materials Used for Sub-Base and Base Course Construction. GSJ: V2018; 6(7): 621-633

  
  

  Abstract

  At the time of industrial development, the production of large amounts of wastage required proper disposal. To reduce the disposal problem, utilization of wastage in construction works is a very important aspect. The reuse of industrial waste had gained high momentum for achieving sustainable waste management locally and globally. Keeping this in mind, research carried out to assess the utilization of molasses, lime, and molasses-lime for improving natural gravel for sub-base and base course construction from the Jimma Jiren quarry site. The natural gravel from this quarry site is known to have poor quality since it did not satisfy the ERA standard specification for sub-base and base course construction. To use Jiren natural gravel as a sub-base or base course construction material, it is necessary to improve its engineering properties. The laboratory test matrix in each test plan included variations in additive type, additive content, and curing period. It was established 8% cane molasses by weight of dry soil as the maximum for effective stabilization of natural gravel for sub-base construction, but not suitable for a base course layer. Results indicated that the natural gravel specimens from the Jiren quarry site stabilized with lime provided higher CBR values than molasses used alone. On the other hand, replacing 50% of lime content with molasses indicated better results than the performance of either individual additive. Therefore, the natural gravel blended with the molasses-lime combination is much better when it used for sub-base and base course construction to treat such an inferior quality of natural aggregates.

  Abstract
  At the time of industrial development, the production of large amounts of wastage required proper disposal. To reduce the disposal problem, utilization of wastage in construction [...]

  • 0
  •  read

• Geotechnical Conditions and Stability Analysis of Landslide Prone Area A Case Study in Bonga Town, South-Western Ethiopia

  E. Quezon

  International Journal of Scientific & Engineering Research (2017). Damtew Tsige, Prof. Emer T. Quezon, Dr. Kifle Woldearegay. Geotechnical Conditions and Stability Analysis of Landslide Prone Area: A Case Study in Bonga Town, South-Western Ethiopia. International Journal of Scientific & Engineering Research. 2017; 8(4): 239-248

  
  

  Abstract

  There were several slides and associated ground subsidence which brought significant impact on the cracking of walls and floor of several private and governmental buildings in Bonga Town. The principal and secondary roads were also affected by subsidence with vertical displacement up to 1m which hampered the traffic in the town. Water pipelines along the road were disturbed by the sliding which was later repaired. Cracking of the walls and floor of more than 120 private residences and more than 10 government buildings were recorded. The main highway that connects Bonga-TepiMasha via Alamo and Gatiba has been disrupted at four locations. This resulted in hampering traffic for several days. This research aimed to evaluate the cause and failure mechanism as well as the stability condition of the landslides. The study involved the investigation of the Geotechnical parameters of soil and the terrain characteristics to be used for the stability analysis of the slope, including distribution and characteristics of soils, the groundwater table, and the depth and geometry of the failures. The Slope stability analysis is supplemented by using Geo-studio 2004 software. Soil samples were collected and were tested for grain size analysis, distribution analysis (sieve & hydrometer) plastic limit, liquid limit, plasticity index, water content, unit weight of soil, specific gravity, and shear strength parameters following the ASTM procedures. Based on the findings, the landslides were triggered by heavy rainfall. Therefore, the main factors controlling the stability of the slope are soil type and characteristics, slope angle, water (surface and groundwater), and slope steepness. The design of the retaining wall is recommended to mitigate the impact of landslides in the study area. 

  Abstract
  There were several slides and associated ground subsidence which brought significant impact on the cracking of walls and floor of several private and governmental buildings [...]

  • 31
  •  read

• Investigation of the Damping Ratio and Shear Modulus of Soil along Light Rail Transit Route in Megenagna-Hayat Road

  E. Quezon

  International Journal of Scientific & Engineering Research (2017). Abenezer Takele, Emer T. Quezon, Tadesse Abebe. Investigation of the Damping Ratio and Shear Modulus of Soil along Light Rail Transit Route in Megenagna-Hayat Road. International Journal of Scientific & Engineering Research. 2017; 8 (1):111-122

  
  

  Abstract

  Soil vibration may also cause by the movement of heavy vehicles and train, which affect adjacent structures along the route. The response of soils for incoming vibration from the train is measured by the dynamic properties of soils such as shear modulus and damping ratio. These soil parameters are very significant to study the ground motion as well as the site response of soil deposits under cyclic loading and soil-structure interaction. About this, the research study has been sought to give some information about the condition, specifically the shear modulus and damping ratio of the soil along the Addis Ababa light rail transit route from Megenagna to Hayat road. Also, this study was dealt with soil distribution along the route, which was conducted to determine soil properties. The sand replacement method was also utilized to investigate the controlling factors for the dynamic soil properties. From related literature, it was known that the dynamic soil properties are influenced by soil types and location of the soil profile. Five Test pits, designated A, B, C, D & E, were considered randomly for soil sampling to determine the properties of soil. The soil samples were taken from a depth of 2.5m below the surface of the roadside. Aside from the soil laboratory testing for common tests, another test was performed using a simple cyclic shear test for the representative samples. The values of normalized shear modulus and damping ratio are compared with already known curves from literature. The research study found out that the values of normalized shear modulus G/Gmax plotted against the shear strain, showed scattered points when it was compared with the curves of Seed and Idriss. Likewise, for the wet clay from the study area, all measured points were close to the known curve of the plot. On the other hand, the values of damping ratio were also compared to curves provided by Seed and Idriss. The Soil properties from all test pits had almost closer values as seen in the plot. However, the sample collected from test Pit D has the highest value of G/Gmax only, while samples from test Pit C has high values both for Gmax and Damping ratio. Test Pit C showed values of Dry density and liquid limit higher than the other test pits. Based on the comparison of the sand; for the strain less than 1%, all measured points of G/Gmax lying close to the extended curve given by Seed and Idriss. The strain of 0.2%, measured points of G/Gmax is closed to curve plot within the boundary, and it was below the curve given by Seed and Idriss. Likewise, for saturated clay, the measured points are close to the curve of Seed and Idriss. The values of damping ratio obtained for strain less than 1% obtained within the range of either the curves given by Seed and Idriss considers sand or clay soils. For strain, less than and equal to 1% the points lie within a range of clay. Therefore, the controlling factor that affects dynamic soil properties from a comparison of shear modulus and damping ratio curves based on consolidation pressure is the confining pressure, which shows high influence on the values of shear modulus and damping ratio based on the test results of the shear strain amplitudes. Index Terms—Damping Ratio, Dynamic Properties, Index property, Normalized Shear Modulus, Sand Replacement, Shear Modulus, Shear Strain Amplitude, Simple Cyclic Shear Test.

  Abstract
  Soil vibration may also cause by the movement of heavy vehicles and train, which affect adjacent structures along the route. The response of soils for incoming vibration from [...]

  • 6
  •  read

• Causes of Delays During Construction Phase of Road Projects due to the Failures of Contractor, Consultant, and Employer in Addis Ababa City Road Authority

  E. Quezon

  International Journal of Scientific & Engineering Research (2017). Amare, Y.; Quezon, ET.; Busier, M. Causes of Delays During Construction Phase of Road Projects due to the Failures of Contractor, Consultant, and Employer in Addis Ababa City Road Authority. International Journal of Scientific & Engineering Research. 2017; 8(3): 15-25.

  
  

  Abstract

  Construction delay considered as one of the most recurring problems in the implementation of construction projects. It is widely known to have an adverse impact on project success in terms of time, quality, and cost. The effect of construction delay is not only confined to the construction industry but also its influence on the overall economy of a country like Ethiopia. This research was conducted to assess the causes of excessive delays in the completion of road projects during the construction phase due to the failures of Employer, Consultant, and Contractor in Addis Ababa City Road Authority projects. Spearman rank correlation coefficient from the Relative Importance Index (RII) analysis was used to test the agreement between different groups of respondents who participated in the questionnaire survey and to rank the three construction parties according to their responsibility area and importance as perceived by the respondents which factor causing the delay of road projects. This research identified sixty-five (65) causes of delay. There were fifty-one (51) valid questionnaires received back from Contractors, Consultants, and Employer (AACRA). Based on the results, the contractors have the highest percentage of responsibility area that causes the delay of about 40%. While the second was on the part of the Employer, which comprised 26.15%, and the consultant which placed third of 23.08%. On the other hand, there were 10.77% of the respondents attested that the Shared groups (3-parties) have the responsibility area which causes project delay during the implementation phase. About this, the research study identified and ranked the top ten factors causing delays of construction projects in Addis Ababa City Road Authority. Poor financial control of the project ranked 1st with Relative Importance Index (RII) of 0.905. Difficulties in financing projects by contractors ranked 2nd with the Relative Importance Index (RII) of 0.854. Type of project bidding and award (lowest bidder) ranked 3rd with an RII of 0.850. Poor site management and supervision of contractors ranked 4th with an RII of 0.839. Selecting inappropriate contractors ranked 5th with an RII of 0.823. Lack of high-technology mechanical equipment ranked 6th with an RII of 0.819. Inaccurate initial project scope estimate and Ineffective project scheduling ranked 7th and 8th with an RII of 0.803. Weak control of the project progress ranked 9th with an RII of 0.788. And the Contractor’s staff is not adequately trained in professional construction management techniques ranked 10th with an RII of 0.784. Therefore, it concluded that the main party Contractor did not perform properly his duties and obligations leading to the main contributory factor causing the failure of the project. 

  Abstract
  Construction delay considered as one of the most recurring problems in the implementation of construction projects. It is widely known to have an adverse impact on project [...]

  • 9
  •  read

• A Study on the Effect of Time Duration by Vibrating or Tamping Fresh Concrete on the Compressive Strength of C-25 Concrete

  A. Achalu, E. Quezon, G. Macarubbo

  Effect of Time Duration by Vibrating or Tamping Fresh Concrete on the Compressive Strength (Select a year). Afework Achalu, Emer Tucay Quezon, Gerry Bangayan Macarubbo. A Study on the Effect of Time Duration by Vibrating or Tamping Fresh Concrete on the Compressive Strength of C-25 Concrete. American Journal of Construction and Building Materials. Vol. 2, No. 2, 2017, pp. 40-47. doi: 10.11648/j.ajcbm.20170202.11

  
  

  Abstract

  Many years ago, consolidation accomplished by laborers wielding a variety of spades, tampers, and similar tools. In Ethiopia, there is no enough knowledge by the laborers, while the site engineers ignored the correct application due to some constraints. The agreement of acceptable vibration level in fresh concrete to which tamping time duration is optimum is an issue to obtain the desired specific compressive strength. This research study aims to evaluate the maximum time length and techniques used to Vibrating or Tamping fresh concrete and its effect on the compressive strength of C-25 Concrete through internal Rodding. Therefore, to study the effects of the period by vibrating or tamping, the needle-type internal vibrator was used to test new concrete cubes based on ACI309R-96. The quality of concrete is important to make physical tests on materials used before any actual experiments to perform. The fresh concrete samples tested by using internal vibration methods and techniques of compaction with different time duration of 1sec, 2sec, 3sec, 4sec, and 5sec. These tests performed by using steel rod in fresh concrete to know the Optimum time of compaction by internal vibration on the cube test of new concrete. Laboratory experiments had been conducted to check the methods and techniques applied to construction sites, as well as site observation on the effects of the vibration time of fresh concrete on the compressive strength and flexural strength of C-25 Concrete with varying vibration time duration and steel rod tamping. Based on the results of cube tests of compressive strength of Concrete Samples have been checked on the 3rd day, 7th day, and 28th day. This research study found out that the Optimum period of compaction was 3sec to produce an acceptable right quality of the concrete mix. Likewise, the flexural strength of the Concrete Sample, when it tested in the laboratory on the 7th day and 28th day, results revealed that the flexural strength improved when vibration time increased, but the amount of water has to be reduced to obtain the desired strength. Finally, Tamping is needed to place fresh concrete in the mold correctly. Furthermore, new concrete produced should match the properties and avoid improper tamping or vibration applications. This situation must not cause differences in the compressive strength of concrete.

  Abstract
  Many years ago, consolidation accomplished by laborers wielding a variety of spades, tampers, and similar tools. In Ethiopia, there is no enough knowledge by the laborers, [...]

  • 0
  •  read

• Contract claim Analysis on Building Construction Project in Addis Ababa: A case study at Yeka Sub City

  E. Quezon

  International Journal of Scientific & Engineering Research (2016). Zenebe, E.; Quezon, ET.; Mosisa, A. Contract claim Analysis on Building Construction Project in Addis Ababa: A case study at Yeka Sub City. International Journal of Scientific & Engineering Research. 2016; 7(7): 1154-1160

  
  

  Abstract

  Contract claims are an inevitable fact of life in the construction industry. Contract claims are one of the problems that construction projects may face. Claims might cause many effects such as payment delay, an extension of time, and work suspension. The main aim of this research was an analysis of contract claims on building construction projects in Addis Ababa, Yeka Sub City by investigating the causes of contract claims and determining the factors to be considered in the selection of appropriate methodology for contract claims analysis. Literature and survey-based studies were made to provide an overview of the different contribution effects of contract claim analysis on building construction projects at the selected site. Interviews were also conducted with the three parties which have direct involvement in construction activities to get concrete ideas on the subject matter. A total of 75 questionnaires was distributed to respondents in Addis Ababa, Yeka Sub City building construction projects. Out of these 12 for client representatives, 35 for contractors representatives, 20 for consultant representatives, and 8 for other companies in order to identify claim causes that occurred in the study area. The quantitative data were analyzed using Excel and SPSS version 20 software, while qualitative data were analyzed by content analysis. The main factors of contact claim cause in the study area were identified. These factors further categorized into four groups; client-related, contract document-related, contractor related and consultant-related factors. While types of delays, knowing the strength and weakness of the project (project complexity) and conditions of the contract were identified as the factor to be considered in the selection of appropriate methodology for contract claim analysis. It is recommended that the three main contracting parties (Owner, Contractor, and Consultant) have responsibility for the effective accomplishment of the project. So each party would take part in their homework on time by developing technical knowledge about the effects of Contract claims on the progressive construction projects. Index Terms— causes, claim analysis, Contract claims, construction project, and risks.

  Abstract
  Contract claims are an inevitable fact of life in the construction industry. Contract claims are one of the problems that construction projects may face. Claims might cause [...]

  • 17
  •  read

• Evaluation of Health and Safety Practice in Building Construction: A Case Study in Addis Ababa

  E. Quezon

  International Journal of Scientific & Engineering Research (2016). Fekele, L.; Quezon, ET.; Macarubbo, YC. Evaluation of Health and Safety Practice in Building Construction: A Case Study in Addis Ababa. International Journal of Scientific & Engineering Research. 2016; 7(10): 122-131

  
  

  Abstract

  The construction industry has been seen as one of the hazardous industries. This is because the industry has a poor health and safety performance record compared to other industries all over the world. Labor law in every nation provides that it is the duty of an employer to ensure that every worker employed works under satisfactory, safe and healthy conditions. The research is focused on evaluating the health and safety issues in building construction projects in Addis Ababa, Ethiopia. The roles of the Client, Consultant and Contractor in health and safety consideration during project implementation were examined. It also determined the factors affecting health and safety performance of laborers. Whether, safety is used as criteria in selecting a contractor during the prequalification phase of public bidding was also identified. Building Construction Companies were involved in the sampling. All the information that could help in attaining the study objectives were collected, reviewed and formalized from the literature review. Data were collected and evaluated and the Relative Importance Index for each factor affecting health and safety was determined. The study determined the practical situation of building construction projects in consideration of health and safety, which was evaluated as low to medium. Relative Importance (RII) index of 12 factors affecting health and safety performance of labors were calculated. The top three factors identified were: (1) Non availability of a clear company Health and safety policy (0.85); (2) Inadequate enforcement of the existing building rules and regulations (0.82); and (3) Safety awareness of the company's top management (0.80). To improve the safety and health performance of building construction projects, the following major recommendations were proposed: each building, construction projects should have their own safety and health policy; include safety as a pay item in contract document; and allocate budget and time frames for health and safety in the contract document. Index Terms— Addis Ababa, Company Policies, Hazards, Health and Safety Practices, Rules and Regulations .

  Abstract
  The construction industry has been seen as one of the hazardous industries. This is because the industry has a poor health and safety performance record compared to other [...]

  • 20
  •  read

• Assessment on the effects of weather change on road construction planning at some selected projects in Addis Ababa and Oromia

  E. Quezon

  International Journal of Scientific & Engineering Research (2016). Befkadu, A.; Quezon, ET.; Busier, M. Assessment on the effects of weather change on road construction planning at some selected projects in Addis Ababa and Oromia. International Journal of Scientific & Engineering Research. 2016; 7(12): 134-145.

  
  

  Abstract

  Road construction in Ethiopia is in high demand to meet its short and long-term goals in infrastructure development programs. The road network is constructed radiating outwards North-South and East-West direction of the Capital City. Some projects are experiencing weather malady due to changing weather conditions in project locations. The study area of this research was focused on some selected projects in Addis Ababa and Oromia. The research had been addressed the effects of changes in weather in the three project planning phases, namely conception planning, design planning, and construction planning. A quantitative research design was used in this study. A literature review was undertaken and the result of which showed that the effects of weather changes are not extensively researched in the construction industry and there are limited references on the effects of weather change within the road construction industry. Sample data were obtained from sixty-three (63) construction practitioners through questionnaires, which were mailed to prospective respondents to assess their opinions. Questions were subdivided into three relevant areas covering demographics, experience with weather change factors, and the effects of weather change on road construction project planning. The study found that the effects of weather change on road construction project planning are similar to those found in other construction industries. The effects of weather change factors on road project planning vary with planning phases. These weather change factors as well as their effects were listed and ranked based on their frequency of occurrence and mean score. An independent sample t-test was used to compare respondents’ opinions on weather change effects between the two sample groups taken in Addis Ababa and part of Oromia. A partial correlation was also employed to identify the relationship between weather change factors and their effect on road construction project planning using SPSS-20. Delay of site preparation activities as a result of weather change on road project conception planning phase has a mean score of 4.30 Addis Ababa and 4.00 in for Oromia, while the influence of weather change on the selection and specification of construction materials for road project design planning phase has the highest mean score of 4.23 for Addis Ababa and 4.03 for Oromia. The effect of weather change on road workers' physiological comfort and quality of work for the road project construction planning phase has the highest mean score of 4.80 and 4.58 in Addis Ababa and Oromia, respectively. The study concludes with recommendations for potential research and with useful information and considerations on the effects of weather change on road construction project planning for construction professionals and project managers.

  Abstract
  Road construction in Ethiopia is in high demand to meet its short and long-term goals in infrastructure development programs. The road network is constructed radiating outwards [...]

  • 2
  •  read