Evaluating Wind Erosion Sensitivity for Landfill Sites in New Mexico Using Fuzzy Analytical Hierarchy Process (FAHP)
Clinton Richardson,
Tracy Sadler
Issue:
Volume 10, Issue 1, January 2022
Pages:
1-12
Received:
17 December 2021
Accepted:
4 January 2022
Published:
15 January 2022
Abstract: The final closure veneer for municipal solid waste landfills must be designed to withstand an allowable annual soil loss from wind erosion over its design life. Veneer sensitivity to wind erosion depends on a multiplicity of intertwined variables. A Fuzzy Analytical Hierarchy Process (FAHP) is used to evaluate weightings for specific forcing function criteria to assess overall wind erosion sensitivity (WES) at current and former landfill locations based on input from multiple decision makers selected from consulting, regulatory, and academe sources. FAHP weights represent the degree of importance of a given criteria relative to an overall criterion. For WES assessment, three criteria were identified: climatic factor (CF) as a function of wind power density (WPD) and effective precipitation index (EPI), vegetation cover (VC), and soil erodibility given as a wind erodibility index (WEI). The results revealed almost equal importance for WPD and VC with WEI being the lesser important criteria. Rankings of thirteen landfill locations in New Mexico showed that Las Cruces was most susceptible to wind erosion with Los Alamos and Clines Corner being least susceptible. The assessment methodology is useful for identifying potential hot spots for wind erosion with respect to the design and maintenance of final cover for landfills.
Abstract: The final closure veneer for municipal solid waste landfills must be designed to withstand an allowable annual soil loss from wind erosion over its design life. Veneer sensitivity to wind erosion depends on a multiplicity of intertwined variables. A Fuzzy Analytical Hierarchy Process (FAHP) is used to evaluate weightings for specific forcing functi...
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An Assessment of Disputes Resolution Mechanisms in Road Construction Projects in Tanzania
Meshack Kabote,
Bavo Blasius Nyichomba
Issue:
Volume 10, Issue 1, January 2022
Pages:
13-22
Received:
30 December 2021
Accepted:
17 January 2022
Published:
25 January 2022
Abstract: Over the years, Tanzania National Roads Agency (TANROADS) has been facing a number of disputes, some of them ending in judicial courts. The reasons for disputes are partly due to having improper handling of project disputes by TANROADS and contactors as caused by both of them having inexperienced technical staff and in part due to having improper framework or having ineffective guidelines on how to handle such conflicts. To determine the extent of the above problems, it was vital to carry out a study by consulting key stakeholders through interviews in form of questionnaires and by case studies of disputed projects in TANROADS. In this regard, factors that cause disputes in the road construction industry were listed down and grouped into four clusters, namely: technical, contractual obligation, managerial and administrative, country laws and political. The current mechanisms to resolve conflicts in road construction were found to include; amicable settlement, adjudication, mediation, expert determination, neutral evaluation, conciliation, mediation, arbitration and litigation. However, these mechanisms have been inefficient, ineffective and lacking guiding framework to resolve such conflicts. Pursuant to the above, it was recommended that contracting parties need to establish the Dispute Review Board (DRB) similar to that used in UK and USA after signing the contract. Members of DRB shall be appointed by the contracting parties and approved by the National Construction Council (NCC). DRB members will be nominated from areas of specialization such as contract management and administration, engineering, procurement, law and finance. DRB members should have adequate qualification, experience, and technical know – how. It is expected that the Board will assist in resolving the disputes speedily and cost virtually exclusive of the necessity for arbitration or judicial courts. This can be achieved by enabling close communication and friendly settlement encouragement of controversial project related issues at the execution level before they become disputes.
Abstract: Over the years, Tanzania National Roads Agency (TANROADS) has been facing a number of disputes, some of them ending in judicial courts. The reasons for disputes are partly due to having improper handling of project disputes by TANROADS and contactors as caused by both of them having inexperienced technical staff and in part due to having improper f...
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Study on the Difference of Microwave Irradiation Effect Caused by the Particle Size Distribution of Rock Minerals
Issue:
Volume 10, Issue 1, January 2022
Pages:
23-30
Received:
11 February 2022
Published:
28 February 2022
Abstract: In the process of microwave-assisted rock breaking, there are many factors that affect the rock breaking effect, among which the particle size distribution of minerals has an important influence. In this paper, the samples composed of common minerals calcite and pyrite in rocks were used as the research object, and six kinds of mineral particle size ratio schemes were set up. By using COMSOL multi-physical field coupling analysis platform, a binary medium analysis model was established to study the distribution characteristics and evolution law of electromagnetic field, temperature field, stress field and plastic zone of the model after microwave irradiation. The results showed that the mineral particle size ratio had no significant effect on the size and distribution of electromagnetic field, while the central temperature of the sample increased with the increase of particle size ratio; with the extention of irradiation time, the larger the particle size ratio, the greater the first principal stress of the model, and the tensile zone appeared in pyrite; The larger the particle size ratio, the earlier the initiation time of plastic zone, the larger the area of plastic zone, and the more obvious the difference of morphological characteristics of plastic zone. When the size of minerals in the rock was uniform, the weakening effect of microwave irradiation on the rock was better.
Abstract: In the process of microwave-assisted rock breaking, there are many factors that affect the rock breaking effect, among which the particle size distribution of minerals has an important influence. In this paper, the samples composed of common minerals calcite and pyrite in rocks were used as the research object, and six kinds of mineral particle siz...
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