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The study aimed to assess the suitability of ceramic waste aggregate and recycled asphalt pavement aggregate as an alternative for base course material. An experimental research design method and Non-Probability sampling techniques were used. The comparative analysis of ceramic waste aggregate and recycled asphalt pavement aggregate were blended with crushed stone aggregate at different proportions by weight and their laboratory result was compared with standard specifications. The study results shown that the aggregate crushing value (ACV) for neat Crushed stone aggregate (CSA) and Recycle asphalt pavement (RAP) are 19.20% and 8.20% respectively and the blended CSA with 10%, 20%, 30%, 40% and 50% of RAP were 18.20%, 16.4%, 15.90%, 14.40%, and 13.10% respectively. Similarly, a 24.32% - 12.06% for Los Angeles abrasion (LAA) and 18.50% - 12.60% for aggregate impact value (AIV) were found to the lower and higher value in the range of the test result. The CBR test for a different proportion of RAP (10% - 50%) blended with CSA was also conducted and an economically acceptable result of 104.20% was found at 30% RAP mix at 98% maximum dry density (MDD). Additionally, the California Bearing Ratio (CBR) test result for 100%RAP at 98%MDD was 49.10%. On the other hand, the experimental tests were conducted on different proportions of Ceramic West aggregate (CWA) (10%, 20%, 30%, 40%, and 50%) which satisfy the principal mechanical properties of aggregate materials. The ACV result for neat CWA is 26.70% while the blended CWA- CSA aggregate was tested with 10%, 20%, 30%, 40%, and 50% of CWA with its complement of CSA as indicated and at 20% CWA replacement of CSA test results were (21.60%, for ACV), (26.31% for LAA), (106.9 for CBR) and (20.60 for AIV). For this investigation an economically acceptable results were achieved by satisfying the Ethiopian road authority (ERA) standard specification limit at 20% CWA and 30% RAP blended with CSA for base course construction material.

Most of the roads constructed in Ethiopia fail prematurely before serving the design life due to various causes arising from many factors. One of the roads that failed before reaching its design lifetime is the Bako to Nekemte Trunk Road. This road was constructed and opened to traffic in 2013. The design pavement life was estimated at 20 years. However; pavement failures have manifested since 2014 after it was opened for traffic. The main objective of this research was to investigate the cause for the failure of flexible pavement on the Bako to Nekemte road segment. To achieve this objective, the study was followed by the experimental research type and purposive sampling method. Also, field observation and pavement condition survey methods for data collection were used. The asphalt, base course, subgrade, and sub-base layer material sampled from the road segment are the material used for this study. Different pavement failures such as rutting, pothole, alligator cracking, raveling, edge cracking, depression, and corrugation were observed along the road section. For estimations of pavement condition index, the road was divided into five different sections based on distress densities, which were measured during the pavement condition survey. From those five sections, four sections were selected for the determination of the Pavement Condition Index (PCI). Using systematic random sampling 159 sample units were evaluated for Pavement Condition Rating (PCR) and the result shows 1.89% excellent, 8.18% very good, 20.13% good, 31.45% fair, 18.87 % poor, 18.24% very poor, and 1.26% failed. Based on PCI value, samples of pavement layer were taken from failed surface condition (1), poor surface condition (2), and none distressed area (1) for comparison purposes. Different quality tests like Atterberg limit, wash gradation, soil classification, compaction test, California Bearing Ratio (CBR), Los Angeles Abrasion (LAA), Flakiness Index ( FI), Aggregate Crushing Value (ACV), Ten percent fines value (TFV), bitumen content, and gradation of asphalt were carried out. The results of these tests were compared with ERA specifications to identify the probable cause of pavement failure. The study found that the cause for failure of flexible pavement in the case of Bako to Nekemte was: insufficient and absence of side drainage structure, traffic loading, poor gradation of base course and sub-base material, and poor quality of subgrade soil. The study also recommended that the road urgently needed routine maintenance as a treatment option to reduce further deterioration and extend its service time.

Ongoing studies show that an effective demand for using natural fibers as a substitution of an artificial fiber in fiber-reinforced composites formation has increased their applicability in an industrial area worldwide. The hydrophobic nature of natural fiber makes week adhesion among the cellulose fiber and matrix components; these problems are usually encountered in fiber-reinforced composites production. To overcome such a limitation of a cellulose fiber, specific physical and chemical treatment strategies were advised by researchers around the world for surface modification of natural cellulose fibers. One of the most basic and efficient surface modification approaches adopted today by the researchers was alkali treatment, widely used in natural fiber composites formation. This technique effectively improved the Mechanical property of natural cellulose fiber, such as tensile strength and flexural properties, while the impact strength result was reduced.

The main problems in road construction and maintance work in Ethiopia availability of a large amount of appropriate quality materials in road construction sites, aggregates in different size fractions are not readily obtainable, necessitating their procurement from long distances, thereby causing an exorbitant increase in construction costs. One of the main problems in constructing the asphalt paving mixture is obtaining a sufficient amount of filler material from crushing fine rock material and low percent using ordinary Portland cement (OPC), hydrated lime (HL) and marble dust. To overcome this problem, it is important to come across alternative filler material to address this gap using naturally available material. Currently, renewed attention has been given to the use of ‘waste’ materials instead of conventional aggregates in pavement construction. This research study investigates the potential use of ‘Enset’ fiber ash as a partial replacement of conventional filler material in hot mix asphalt supported by experimental laboratory investigation. In order to achieve this study, purposive sampling techniques were adopted to select the sample size and location. The study evaluated the potential of ‘Enset’ fiber ash as filler for the design of dense-graded hot mix asphalt by referencing traditional filler control mix procedures based on standard specifications, and a crush rock filler was utilized as a conventional filler material as a control for comparison. The Marshal Stability and Rutting Test (RT) was conducted to determine the HMA specimen's performance. Several HMA specimens were prepared using aggregate blend according to ASTM D 1559 with four different percentages of ‘Enset’ fiber ash (EFA) of 15%, 25%, 35% and 45% filler replacement the total filler weight used in the control mix. Specimens were prepared and tests performed according to EN 12697-22 procedure-B for rutting test. All HMA properties were taken at 4% air void and determined their optimum bitumen content (OBC). Almost the same result with the control mix was observed in the study at 15% and 25% of the ‘Enset’ fiber ash (EFA) replacement. However, higher Marshall Stability, a lower void filled with asphalt, better flow, a good void in mineral were observed at 25% ‘Enset’ fiber ash (EFA) replacement. At this rate, the rutting performance is less than that of the control mix but is within the specifications of 2.78mm and 2.9 mm of rutting depth less than 6mm that satisfies the EN 13108 requirement. As a result, Enset fiber ash filler can replace traditional filler material up to 25% of the total filler weight used in this study. It was recommended to use ‘Enset' fiber ash (EFA) as a filler material as a partial replacement in a bituminous paving mixture up to the specificed percentage by weight replacement.

Understanding the behavior of expansive soil and adopting the appropriate control measures should be great for civil engineers. Extensive research has been going on to find the solutions associated with problems of expansive soils. There have been many methods available to control the expansiveness of these soils. The removal of expansive soils and replacement with suitable material has been widely practiced worldwide. Reasonable material is available within economic distances; however, suitable materials is not readily an available in urban areas for borrowing, which has to be hauled from a long distance. Instead of borrowing suitable soil from a long distance away, after stabilization with cost effective and readily available industrial and agricultural waste materials, it is economical to use locally available plastic soil. Such wastage products are also used to minimize environmental hazards such as CO2 in the atmosphere to minimize the percentage of industrial products used for stabilization, such as cement. Marble dust (MD), an industrial waste product, Rice husk ash (RHA), agricultural waste products, and cement are industrial products in this present study. The general objective of study was to examine the effects of poor subgrade soil stabilization using the mixture of MD, RHA and cement to enhance sub-standard soil engineering properties to be used as subgrade materials. Moisture content, Atterberg limits, grain size analysis, soil classification, free swell index, basic gravity, compaction (maximum dry density, optimum moisture content) and CBR value test have been calculated in this analysis. The design of the analysis followed by the experimental method of study were adopted, which started with sample selection. A disturbed samples was collected from the pit at a depth of 1.5 m to 2m from ground level in order to avoid the inclusion of organic matter by considering the free swell index value and observation was considered. The chemical analysis of MD and RHA was conducted in laboratory and the main oxides are (SiO2+Al2O3+Fe2O3) were 70.13% for RHA and 42.43% for MD. The RHA chemical properties satisfy the requirement, while MD did not meet the requirement of ASTM C 618. The Gomata Teachers’ Condominium (GTC) soil sample laboratory result have 42.72% plastic index (PI), 85% free swell index and its CBR value of 2.265%. The Millennium Secondary school (MSS) soil sample has a 48.79% PI, 87% free swell index and 2.121% CBR value. Therefore this soil samples are highly expansive were checked before any stabilizations process based on their plasticity index and CBR value based on standard specification requirement , then stabilization was achieved by stabilization by proposed (0,8MD,6MD+2C,4MD+4C,2MD+6C,8C,6MD+2RHA, 4MD+4RHA, 2MD+6RHA,8RHA,6RHA+2C,4RHA+4C,2RHA+6C,2MD+2RHA+4C,4MD+2RHA+2C, 2MD+4RHA+2C) proportion. Then LL, PI, OMC, and CBR decreased as the cement ratio increased, while PL, MDD and CBR value increases instead of MD and RHA increases, however, as MD and RHA increase, the quantity of cement decreases. The laboratory outcome was compared with the requirement of Ethiopian road authority standard, ASTM and AASHTO. Based on this study all mixing stabilizers (MD-cement, RHA-cement, MD-RHA, MD-RHA-cement) and 8% of RHA and cement fulfill the ERA standard specification requirements for its CBR swell value. However, 8% of marble dust alone does not fulfill the Ethiopia road authority requirements for CBR swell. The MD and RHA standalone does not improving some of the engineering properties of soil samples used for subgrade construction. However, they mixed with different percentages of cement can effectively stabilizer for this expansive soil for road sub-grade construction.

Currently, researchers are more focusing on eco-friendly materials, sustainability, and low consumption of energy during the stage of handling, low initial cost, have appropriate mechanical properties and biodegradable and less susceptible to health hazards are the main challenge facing in the present day across the world especially to developing new materials that would improve the industrial supplies for making lightweight materials. Therefore; natural cellulosic fiber one, of effective strategies to substitute artificial fibers for its own benefits when compared and mainly concentrating to reinforce polymer matrices by natural cellulosic fiber due to their decomposable characteristic in nature. This an overview mainly discussed on commonly available natural fiber property such as physical property, chemical composition analysis, surface morphology analysis such as thermal stability analysis (TGA), Fourier Transform Infrared (FTIR) analysis and Scanning Electron Microscopy (SEM) to be adopted in order to characterized natural fiber and impact of treating natural fibers by appropriate chemical on certain properties was discussed by supporting literature. In addition to this the significance of characterization of natural fiber briefly discussed and this an overview will helps other researcher’s source for natural fiber composite studies in future studies.

Concrete crack is one of the main problems observed in concrete technology due to drying shrinkage. Incorporating fibers in concrete production is one of the mechanisms implemented to mitigate cracks. Nowadays, investigators concentrate on different techniques to replace human-made fiber with existing natural fibers for fiber-reinforced composite material. Utilization of natural fiber has an initiation for the development of eco-friendly materials by reducing damages caused by human-made materials and saving nonrenewable resources. Natural fibers are readily and abundantly available, sustainable, and biodegradable, with low cost and low density, and have superior specific properties. Nevertheless, there are some limitations of natural fiber compared to human-made fiber. Consequently, significant energy was applied to alter natural fiber’s surface and morphology using physical, chemical, and biological treatment techniques to overcome the limitation. The primary intention of surface treatment is to modify the bond between the fiber surface and the polymer matrix. However, based on this literature review, there were no specific treatment techniques to be followed to select the best one from the others as criteria. It should include all parameters to consider starting from the stage from the cradle to the grave, cost of chemicals, transportation, and labors, including energy consumption and effluent energy. Additionally, their environmental effect also investigated in detail to compare each other.

The main objective of this study was to evaluate the suitability of recycled asphalt aggregate with fresh aggregate in hot mix asphalt production by using experimental laboratory investigation. Also, Non-probable sampling techniques were adopted to collect a sample. The engineering properties of extracted Reclaimed asphalt pavement aggregate and the fresh crushed aggregate were identified based on standard specification before starting the Marshall Mix design, Then the Marshall Stability test was conducted on crushed aggregate with three different aggregate gradation sizes 5.0%, 5.5% and 6.0% by weight of aggregates and with five different bitumen content 4.0%, 4.5%, 5.0%, 5.5% and 6.0% by weight of total mix. Depending on the selected aggregate gradation Marshall Stability test was conducted for reclaimed asphalt pavement aggregate with a replacement rate of 5.0%, 15%, 25%, 35%, 45%, 55%, and 65% by weight of crushed aggregate to determine its optimum bitumen content according to National Asphalt Pavement Association method (NAPAM). A total of 64 mix designs and 190 specimens were prepared. Hence, Marshall Stability and Moisture Susceptibility test with 3-trials, hence rutting test with 2-trials. From 190 specimens, 45 were for the control mix, 105 were for replacement proportion, 36 were for Moisture Susceptibility and 4 were for Rutting Based on the Marshall Test results and their performance tests such as Moisture Susceptibility and Rutting was performed to maximum allowable replacement percentage was compared with standard specification. The optimum bitumen content result obtained in percent was 5.1, 5.04, 4.98, 4.87, 4.81, 4.74, 4.67 and 4.53 for 0 % (control), 5.0%, 15%, 25%, 35%, 45%, 55% and 65%, respectively. The experimental value of Tensile Strength Ratio, proportional rut depth and mean rut depth on 45% RAPA replacement was 85.42% and 4.48 %, 2.24 mm respectively. Finally, the test result obtained from the marshal stability and the performance testes indicates that up to 45% replacement of aggregate is reclaimed asphalt pavement aggregate in hot mix asphalt production satisfies the standard specification. Keywords: Reclaimed asphalt pavement; Marshall Test; Crushed aggregate; Tensile Strength Ratio; Proportional rut depth.

Know a day’s utilization of local accessible materials is an important stage for sustainable, economic building material on the earth surface. Within them Brick is one of the commonly used construction material around Jimma town due to the availability of clay soil. But brick produced by small micros un-skill enterprises rather than by traditional method, its quantity was small and its quality was unsatisfactory, because it can easily break and it has high water absorbing conduct. The purpose of investigation was be to improving the properties of clay soil properties by using Literate soil for in the manufacturing of bricks for masonry units. In order to achieve this researches include, non-probability sampling techniques was be used to collect samples in Jimma area, then collected of samples prepared for different laboratory test and by partially replacing literate soil by 5%, 10%, 15% and 20% on a clay soil in order to get optimum property by different mix ration for different laboratories. Test results indicated that shows that the lightweight bricks could be made from this study without any deterioration in the quality of bricks. Additionally, the compressive strength of the blocks optimum at 15% lateritic soil replace in clay soil contents. The optimum firing temperature furnace at a duration burning of brick was at 1000°C. It’s shown that bricks prepared of clay-laterite earth capable for high resisting capacity rather than for beauty. Key words: Literate soil, Brick, Clay soil, Compressive strength, Water absorption, sustainable, Density, Construction material.

Recently, highway and construction industries utilize a substantial quantity of conventional aggregates. The increasing demands for conventional aggregate cause an increase in the cost of construction, reduction of natural resource, and continuing deterioration of the earth's surface. On the other hand, the waste generated from the marble industries during the process of cutting and polishing was increasing day by day all over the world. In Ethiopia, the use of Marble Waste Aggregate materials in road construction as a base course material was not well-known, and it was simply wasted at every place where the marble production was continuing. Therefore, this paper focused on evaluating the possibility of using marble waste aggregate as conventional aggregate in the base course layer of flexible pavements by experimental method. To achieve the objectives of the research, mechanical stabilization and laboratory tests have been carried out at different percentage replacement of Conventional Aggregate by (0%, 20%, 40%, 50%, 60%, 80%, and 100%) of Marble Waste Aggregate weights. Marble wastes materials are collected from Burayyu city, Alisha marble processing industry. The laboratory test results for MWA indicated SG, ACV, AIV, LAA, Flakiness Index , Elongation Index, Plastic Index, Water Absorption, and CBR of 2.74%, 23.63%, 26.21%, 27.03%, 26.48%, 13.29%, Non Plastic, 0.50% and 73.3%, respectively. These test results fulfilled the ERA standard specification for some tests, and it showed marginal quality values to the standard specification for GB2 and GB3 base course materials. CBR and gradation test results shown failure to meet the standard specification. Thus, mechanical stabilization was done to improve the mechanical and physical properties of Marble Waste Aggregate. Blending of 80%MWA with 20% CA results in SG, ACV, AIV, LAA, Flakiness Index, Elongation Index, Plastic Index, Water Absorption, and CBR of 2.83%, 18.2%, 21.52%, 22.58%, 23.79%, 16.29%, Non Plastic, 0.80%,and 82.5% respectively. At this proportion the gradation also observed to fit with the required ERA standard specification of GB2 and GB3 materials. Therefore, the use of marble waste aggregate up to 80% by weight is recommended for road base course layer, when it is found near to the construction site and in places where the materials are abundantly available.

Currently, due to global warming, a lot of investigation and advance has been growing in the possible use of natural fibres composite universally. Scholars highly initiated the significance due to its advantage of human-made fibres, such as little ecological impact and low cost. Many studies were established to enhance the mechanical execution and uses of natural fibre in the manufacturing trade. Investigation revealed on natural fibre composites can be set into a load-bearing structural and infrastructure use. As an engineered usual material, related to human-made fibre composites, the attributes of natural fibre compounds can be oriented to attain a positive request. The common problems in operational with natural fibre compounds were excessive discrepancy and appearances. Natural fibre composites’ attributes, which have a significant level, are mostly subjective by the category of fibres, ecological circumstances also the source of cellulose fibres, and the kind of fiber treatments. As the addition of natural fibre increases in fiber-reinforced concrete production, its slump test value decreases, but it improves the mechanical property of concrete up to a certain value. Then, it starts to decline compared to the control mix design and also, the mode of failure changes from brittle to ductile with the inclusion of natural fiber. Though, cellulose fibre composites might appear as a novel substitute for a rock-solid material with their uniqueness and unevenness and substitute expensive human-made fiber composites. This assessment will deliver an overview of natural fibre mechanical performance and toughness in the concrete, one of the importance of natural fibre compared to a human-made one, and the detailed achievements on its uses supported by the literature.

Unsuitable soil materials along the alignment of road projects have a significant influence on planning, design, construction, and maintenance. Expansive soils are susceptible to considerable volume changes due to seasonal variations and moisture content. Most soils found in Jimma and Ambo Zones composed of plastic clay soil, causing severe damage at the intermittent of pavement sections. This research study conducted laboratory investigation considering combinations of materials blended to stabilize the expansive soil for subgrade construction. An experimental type of study performed which started by collecting specimens. Two clayey soil specimens considered to test the free swell index obtained from a depth of 1.5m to remove the organic impurities. Results indicated the chemical analysis of pumice contained 82.68%, while its physical properties of the test of fineness specific surface and residue on 45 microns showed 3770 cm2/gm and 30%, respectively. As the lime content increased, the CBR strength also increased. But, if the percent content of lime decreased with an increasing pumice content, the CBR value did not show any significant increase. Both the chemical and physical properties satisfied the requirements according to ASTM C-618. Hence, this experiment obtained 7% lime + 3% pumice as an optimum mix ratio to stabilize expansive soils.

Ethiopia is party to the Convention on the Rights of the Child and its two substantive Protocols. Ethiopia’s reporting history to the Committee on the Rights of the Child is better in terms of complying with periodicity and participation than its reporting histories to other treaty bodies. Ethiopia submitted four reports to the Committee and received recommendations. This article aims to examine the implications of these recommendations on domestic child rights framework. Ethiopian delegates to the constructive dialogues made a number of promises and submitted reports of compliance with regard to the Committee’s recommendations. Concluding observations of the Committee, which are checklist of compliance with conventional obligations, can be considered as soft obligations on the government of Ethiopia. Though concluding observations cannot sufficiently reach domestic law-making process and the law making organs, propelling role of the observations in the adoption of domestic laws, policies and plans of action is observed. With regard to the interpretative relevance of concluding observations, this article shows that there is no analytical mode of treaty application and prescribed principles of treaty reference, which would have paved the way for utilizing the concluding observations of the Committee in interpreting child rights treaties.Keywords: concluding observations, constructive dialogue, Convention on the Rights of the Child, recommendations, reporting, rights of the child

For over a century, paved roadways have been constructed using asphalt concrete mixes across the world. This research was aimed on evaluation of the effect of the waste rubber tire modified bitumen on Asphalt performance, to investigate physical properties such as the stability and flow. Marshall Stability Method was used to determine the Optimum Binder Content (OBC) and to evaluate the properties of the crumb rubber. Five different percentage of rubber by weight of bitumen: 0%, 5%, 10%, 15%, 20% were used. A comparative study is made among the unmodified and modified bitumen samples using the various sizes of waste rubber tire bitumen particles and the modified. The results of the study revealed that as rubber content increase from 0 to 20% penetration decreased from 68.5 to 58.5 mm. Similarly, for the same percentage increase in rubber content ductility decrease from 100 to 75 cm. Asphalt mixes with crumb rubber 15% have higher stability, it is two times more than the minimum specification and lower marshal flow. From this study it is concluded that recycled crumb rubber can therefore be beneficial to the performance of the asphalt concrete pavements as well as provide a means of safe disposal of these non-biodegradable wastes.

Expansive soil refers to a particular type of soils – almost clayey soils in property - that expand as they absorb water and shrink when they dry out. The process of swelling generates pressures that can cause lifting, or heaving of structures whilst shrinkage process can cause differential settlement on civil structure. A large number of buildings and roads are placed on such type of soil and exposed to the danger from this swelling and shrinkage processes. In order to avoid the previous mentioned risk from the expansive soil, a technique of soil stabilization should be made for this type of soil to enhance some of its properties. In this study, the experimental investigations have been made to study the suitability of natural gravel from jiren quarry site to improve properties of expansive soil. The important parameters to be determine the geo-technical properties such as Specific gravity, Liquid limit, Plastic limit, Plasticity index, dry density and California Bearing (CBR) ratio values. According to ERA 2002 this type of soils is poor for subgrade for road construction. In order to realize the desired objective, a purposive sampling technique which is non –probability method was adopted in order to collect disturbed soil samples at depth of 1.5m and natural gravel from jiren quarry site used for the preparation of different laboratory tests. The laboratory work involved sieve analysis along with consistence test to classify the soil sample. The preliminary investigation of the soil shows that it belongs to A-7-5 class of soil in AASHTO and CH in USCS soil classification system. Soils under this class are generally of poor for subgrade road construction. Atterberg limits, compaction and CBR tests were used to evaluate properties of stabilized soil. The soil was stabilized with natural gravel in stepped concentration of 5%, 10%, 15%, 20% and 25% by dry weight of the soil. Analysis of the results shows the addition of natural gravel improve the geotechnical properties of the expansive black cotton soil. The addition of natural gravel reduces plasticity index, swelling and OMC with an increase in MDD and CBR with all increased natural gravel contents. The addition of 20% and 25% of natural gravel established an increased CBR value by 670% and 958% respectively, indicating the subgrade class falling under S4 and S5 respectively. From this study it was found out that natural gravel stabilized with soil do meet the minimum requirement of ERA pavement manual specification for use as a sub-grade material in road construction.

For many Karl Marx is the symbol of extreme right nihilists. Marxism has posed its own finger print on major developments of the 20th century. However, it has been, for long, preferred to be skeptic on discourse of human rights view from Marx perspective. Even if some scholars have tried to reflect on the subject matter, the literature lack objectivity in a sense of taking Marx as antinomian or right-phobia. In this paper I will disprove the mainstream allegations through revealing the exact pictures portrayed by Marx in "On the Jewish questions", "Critique of the Gotha Program" and "the Communist Manifesto" of which basic conclusion was Marx did not generally reject rights, instead made a systematic classification and separate treatment of the so called human rights.