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Effect of Gypsum in Proportion of Other Additives Used in Stabilizion of Deficient Soils: A Review
Muhammad Aishat Sani,
Adamu Umar Chinade,
Abubakar Mamuda,
Ahmad Batari,
Muhammad Dalhatu Abdullahi
Issue:
Volume 6, Issue 6, December 2021
Pages:
161-176
Received:
19 October 2021
Accepted:
29 November 2021
Published:
7 December 2021
Abstract: Soils viable for engineering works needs to attain certain strength properties in order to serve its intended purpose. Some available soil like Black Cotton Soil tends to show weakness in strength which necessitate it to be modified so that the desired strength can be achieved, this can be executed using materials that could improve the soil properties such as gypsum, lime, bagasse ash, cement, etc. This paper is a review of the viability of the use of gypsum in proportion to other stabilization material to improve the strength properties of soils. Research shows, gypsum in addition to other stabilization materials such as bagasse ash, rice husk, lime, NaCl, tin, fly ash, jute fibre etc. produce a better stabilized soil as compared to gypsum or any of this material as stand-alone stabilizer. Laboratory result after series of experiment to determine the Maximum Dry Density and Optimum Moisture Content, Unconfined compressive strength, California bearing ratio CBR and Atterberg limit values of the stabilized soil using gypsum with other additives, reveals that for effective soil stabilization with the use of gypsum and any other additives is a function of the type of soil being stabilized, nature of additives, percentage of applied additives, curing time, also the classification of the soil to stabilized. It is found that the use of these additives in proportion of each other, their percentage proportioned, curing time and the nature of soil, give different end point of stabilized soil.
Abstract: Soils viable for engineering works needs to attain certain strength properties in order to serve its intended purpose. Some available soil like Black Cotton Soil tends to show weakness in strength which necessitate it to be modified so that the desired strength can be achieved, this can be executed using materials that could improve the soil proper...
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The Effects of Variations on the Final Cost of Selected Public Building Projects in Akanu Ibiam Federal Polytechnic, Unwana from (2010-2020)
Mbabuike Udochukwu Cyprian,
Onoh Felix Emenike,
Nnadi Ezekiel Oluwaseun,
Okpan Agara
Issue:
Volume 6, Issue 6, December 2021
Pages:
177-187
Received:
11 October 2021
Accepted:
30 October 2021
Published:
7 December 2021
Abstract: Most executed public building projects in Nigeria have a difference between their tender/initial contract sum and final contract sum, and this difference is often caused by variations. Where not properly handled, variations lead to delays, dispute and sometimes project abandonment. The effects of cost of variations on the delivery of public building projects in Nigeria have long been a source of concern to stakeholders. In view of this, the study examined the effects of variations on building costs of selected building projects in Akanu Ibiam Federal Polytechnic, Unwana (AIFPU) executed within the period (2010-2020), with the purpose to determine their effects on cost of building projects. Historical research design was adopted. Secondary data were used in the analysis. Data on ten (10) completed projects of varying characteristics were collected from the institution’s physical planning unit using purpose sampling. SPSS version 20 tool was used in descriptive analysis of the estimate of the mean, percentage and standard deviation. E-view 8 tool of inferential statistics of regression and correlation were used in the analysis and testing of the hypothesis. The result indicates that increase in cost of variation will lead to 0.881 increase in contract sum. Results also indicate that significant positive relationship exist between variations and final cost of projects with coefficient of determination (R2)=0.602987 tested at 0.05 level. This result indicates that cost of variation has an impact on the final cost of building project and should be guarded against. It was recommended that there should be detailed and continuous planning including costing of a project right from the inception of the project to the completion, involvement of professionals and contactors at the initial stage in order to reduce variations in the project, timely advance payment for procurement should be made among others in others to guard against the impact of variation on public building projects.
Abstract: Most executed public building projects in Nigeria have a difference between their tender/initial contract sum and final contract sum, and this difference is often caused by variations. Where not properly handled, variations lead to delays, dispute and sometimes project abandonment. The effects of cost of variations on the delivery of public buildin...
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Influence of Particle Size and Moisture on the Compression Behaviour of D-G-S
Tae-Gew Ham,
Jin-Hwan Lim,
Man-Bok Ha
Issue:
Volume 6, Issue 6, December 2021
Pages:
188-195
Received:
29 October 2021
Accepted:
24 November 2021
Published:
11 December 2021
Abstract: Most studies in geotechnical engineering have focused on soil behavior under low pressures, low stress levels which are typically encountered in many geotechnical projects. But high stresses can lead to particle breakage of even the strongest soil minerals. In addition, many weak-grained soils, such as decomposed granites, carbonate sands, and volcanic ashes, are also crushable and compressible under normal working loads. Hardin stated the degree to which particles are crushed during shearing depends on many factors, such as particle-size distribution, state of effective stress and effective stress path, void ratio, particle hardness, and presence or absence of water. However, these studies have focused mainly on dry particles and the influence of water on the crushing properties of particles has not been sufficiently studied. It is important to mention that characterization of the behavior of D-G-S (decomposed granite soil) is important because this material is commonly used for construction in many engineering projects in Japan and Korea. Therefore, in this patter in order to investigate the influence of particle size and moisture on compression characteristics of D-G-S, single-particle crushing and one-dimensional compression tests were carried out on three types of D-G-S as well as on quartz-rich silica sand under both dry and wet conditions. Results showed that it can be seen that there is a relationship that the crushing strength decreases as the particle size increases. this result was clarified that the same result can be obtained not only in Silica but also in D-G-S. and the initial crushing strength of a single particle was reduced and strength variability increased due to the weakening effects induced by the presence of water. Moreover, it was observed that the one-dimensional compression behavior of decomposed granite soil was related to the initial crushing strength. Finally, the magnitude of initial crushing strength was also affected by the degree of weathering of the soil.
Abstract: Most studies in geotechnical engineering have focused on soil behavior under low pressures, low stress levels which are typically encountered in many geotechnical projects. But high stresses can lead to particle breakage of even the strongest soil minerals. In addition, many weak-grained soils, such as decomposed granites, carbonate sands, and volc...
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Characterizing Traffic Offenses in Addis Ababa, Ethiopia: Case Study in Arada Sub-city
Gadisa Layo Mosisa,
Getu Segni Tulu
Issue:
Volume 6, Issue 6, December 2021
Pages:
196-201
Received:
8 November 2021
Accepted:
2 December 2021
Published:
24 December 2021
Abstract: Addis Ababa, the capital of Ethiopia, is undergoing a period of substantial growth. However, the road transport system faces major challenges. The level of road traffic crashes is increasing from time to time as the number of vehicle population and urbanization increases. Systematic analysis of available data from a different perspective and implementation road safety policy to reduce traffic crashes are interesting work in the coming years. Factors that are responsible for road traffic accident are categorized into driver error, pedestrian, road environment and the vehicle factor. Driver error and noncompliance of drivers with road traffic rules and regulations is the main factor for road traffic crashes which accounts for approximately 90%. This study aimed to know the characteristics, most common traffic offenses, their magnitudes and trends on the roads of Addis Ababa city, particularly in Arada sub city from November 2014/15 to November 2016/17 GC. The Traffic offence data in Arada Sub city, vehicle population details and driver population details in the Addis Ababa city were collected. Proportions, frequencies and descriptive statistics were used to analyze the data. Results indicate that the amount of traffic offenses over a three - year period increased by 13.7% and decreased by 2.4% for male and female drivers respectively. In addition, male traffic offenders (95.6%) outnumber women traffic offenders (4.4%) by a wide margin in traffic violations as compared to licensed male (85.6%) and female (14.4%) drivers in the city. Traffic flow obstruction (12.9%), disrespecting prohibited signs (11.3%), illegal parking (8.5%), overloading (8.2%) and driving while talking on the phone (7.8%) were most commonly occurring traffic offenses. Stricter measures and educations on road safety awareness need to be reinforced.
Abstract: Addis Ababa, the capital of Ethiopia, is undergoing a period of substantial growth. However, the road transport system faces major challenges. The level of road traffic crashes is increasing from time to time as the number of vehicle population and urbanization increases. Systematic analysis of available data from a different perspective and implem...
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Proper Mix Proportion and Construction Method of Waste Concrete Using Recycled Coarse Aggregate in Site Considering Environment
Nam Wook Kim,
Min Hwan Kim
Issue:
Volume 6, Issue 6, December 2021
Pages:
202-207
Received:
20 November 2021
Accepted:
14 December 2021
Published:
24 December 2021
Abstract: When the concrete waste is recycled as the aggregate, the concrete waste is generally carried to the plant and the recycled aggregate is manufactured. However, in this method it needs significantly much energy and causes much CO2 when the concrete waste is carried to the plant. Therefore, it is need to consider about environment to study on recycling of concrete waste in site. In this study, it is investigated, appropriate mix proportions used recycled coarse aggregate, properties of fresh concrete, pumpability, and properties of hardened concrete in case recycling of concrete waste in site, and when the mortar is brought to the site and the recycled coarse aggregate in the dry state is used, the recycled coarse aggregate is put into the mortar in which the amount of water corresponding to the water absorption rate of the recycled coarse aggregate in the dry state is corrected, it is discussed the freshness and curability of the concrete produced in the above, as well as the aging and pumping properties of the slump. From the scope of this study, when the mortar is brought into the site and the recycled coarse aggregate in an air-dried state is put in the site, if the amount of water corresponding to the effective water absorption rate of the regenerated coarse aggregate is corrected at the mortar manufacturing stage, the compressive strength and tensile strength, the static elastic modulus and the chloride ion penetration depth were about the same as when the recycled coarse aggregate in the surface dry state was used. In addition, it is considered that the same degree of fluidity as when the recycled coarse aggregate in the surface dry state is used even after pumping.
Abstract: When the concrete waste is recycled as the aggregate, the concrete waste is generally carried to the plant and the recycled aggregate is manufactured. However, in this method it needs significantly much energy and causes much CO2 when the concrete waste is carried to the plant. Therefore, it is need to consider about environment to study on recycli...
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