Department of Construction & Wood Technology Education

Permanent URI for this collection

https://ir.aamusted.edu.gh/handle/123456789/555

Browse

Browsing Department of Construction & Wood Technology Education by Issue Date

Filter results by year or month
Now showing 1 - 20 of 181
  • Item
    Effect of species, particle size and compacting pressure on relaxed density and compressive strength of fuel briquettes
    (International Journal of Energy and Environmental Engineering, 0004-01-30) Mitchual, Stephen J; Frimpong-Mensah, Kwasi; Darkwa, Nicholas A
    Densification of biomass waste materials has provided a great boost to the utilization of wood and agricultural waste for domestic and industrial fuel. However, the processes involved in the production of this fuel make it more expensive than fossil fuel. This is because densification of wood waste into fuel briquettes is not simple. This paper reports the results of research conducted to determine the effect of species, particle size and compacting pressure on relaxed density and compressive strength in cleft of briquettes produced from sawdust of tropical hardwoods. Briquettes were made using a laboratory hydraulic press. Compacting pressure was varied from 10 to 50 MPa at an interval of 10 MPa. Species used were Triplochiton scleroxylon, Ceiba pentandra, Aningeria robusta, Terminalia superba, Celtis mildbreadii and Piptadenia africana. The results indicate that species, compacting pressure and particle size of sawdust at 5% level of significance have significant effect on the relaxed density and compressive strength in cleft of briquettes produced. The multiple correlation coefficient (R) and adjusted R2 for the regression model between relaxed density of briquettes, and species density, particle size and compacting pressure were 0.93 and 0.87, respectively. Additionally, the multiple correlation coefficient and adjusted R2 for the regression model between compressive strength of briquettes, and species density, particle size and compacting pressure were 0.83 and 0.69, respectively. The regression models suggest that species density, particle size and compacting pressure are good predictors of relaxed density and compressive strength in cleft of briquettes produced from sawdust of tropical hardwoods.
  • Item
    Planing and Turning Characteristics of Gmelina arborea Grown in Two Ecological Zones in Ghana
    (Original Research Article, 0201) Mitchual, Stephen J.; Minkah, Maxidite A.; Owusu, Francis W.; Okai, Reynolds
    Gmelina arborea grown in Ghana has not been promoted for its efficient use by the wood industry due to the limited technical information available and is therefore classified as a lesser-used timber species. This paper presents research findings on the planning and turning properties of Gmelina arborea cultivated in two ecological zones in Ghana. Samples of logs from six trees of the species were obtained from Daboase and Abofour in the Wet Evergreen and Dry Semi-Deciduous Forest zones of Ghana. These were crosscut into top, middle and butt sections using a chainsaw. An LT 15 Wood-Mizer bandsaw was used to saw each log into 2.6 cm-thick boards; these were then stacked for air drying. Planning and turning tests were conducted following the American Society for Testing and Materials International D1666-87-2004 method to determine the machining characteristics of
  • Item
    Statistical optimization of the physical and mechanical properties of briquettes of celba pentandra sawdust and agricutural residue
    (PRO LIGNO, 0202) Afrifah, Kojo Agyapong; Asiedu-Agyei, Ebenezer Oku-Ampofo; Mitchual, Stephen Jobson
    Utilization of biomass residue from agricultural and sawmilling activities for energy would reduce the pressure on forest stands. This study characterized briquettes made of Ceiba pentandra sawdust, oil palm empty fruit bunch, and sugarcane peels at varying compacting pressures as alternative sources of energy. Using two level factorial design analyses, statistical models describing the relationships between material compositions of the briquettes and their physical and mechanical properties such as shatter index, impact resistance index, compressive strength in cleft and relaxed density were derived. Combinations of pressure and materials for manufacturing briquettes with standard physical and mechanical properties were also determined using numerical optimization. Generally, increasing the compacting pressure improved the physical and mechanical properties of the briquettes. Oil palm empty fruit bunch content impacted negatively on all the properties. Contrastingly, Sugarcane peels and Ceiba pentandra sawdust had a strong positive effect on most of the physical and mechanical properties. All the briquettes were durable recording an average of 98% shatter resistivity. The optimization results generated briquettes with standard shatter index (98 %), impact resistance index (117.08 – 239.25 %), compressive strength in cleft (20 N/mm), and relaxed density (363.23 – 504.75 kg/m3 ) suitable for packaging, transportation, storage, and domestic utilization. Generally, this study indicates that briquettes with good physical and mechanical properties can be produced from Ceiba pentandra sawdust, oil palm empty fruit bunch, and sugarcane peels at low compacting pressure. Additionally, briquettes with specific desired attributes could be produced by varying the compositions of the materials and compacting pressure.
  • Item
    Assessment of the drying behaviour of young and mature Bambusa vulgaris from Ghana
    (Advances in Bamboo Science, 2003) Awotwe-Mensah, Michael; Mitchual, Stephen Jobson; Appiah-Kubi, Emmanuel; Kessels Dadzie, Peter; Mensah, Prosper; Donkor, Mark Bright
    This study assessed the drying behaviour of young and mature Bambusa vulgaris culms and evaluated their uti lisation potential. Two and four-year old Bambusa vulgaris culms were harvested and prepared to the required length of 21 internodes. The first seven internodes were taken as the bottom, the second seven were taken as middle and the last seven internodes were taken as the top. The study used samples from the bottom and top. Physical properties, including basic density and moisture content, were determined in accordance with ISO 13061–2 (ISO 2014) and EN 13183–1 (EN 2002), respectively, while shrinkage properties (radial, tangential, longitudinal and volumetric) were determined following established procedures. For the bottom and top portions of the mature bamboo after 18 days of drying, radial shrinkage values were 3.31% and 5.01%, tangential values were 4.95% and 5.78%, and longitudinal values were 0.28% and 0.35%, respectively. For the bottom and top portion of two-year-old culms, the values were 15.0% and 18.6% for radial shrinkage, 20.5% and 25.8% for tangential shrinkage and 0.46% and 0.47% for longitudinal shrinkage, respectively. The tangential shrinkage values were higher than the radial and longitudinal shrinkage values. The moisture content of the bottom part of the mature bamboo culm after 3 and 18 days of drying were 31.4% and 12.2%, while the young culms had values of 53.5% and 27.8%, respectively. Mature bamboo culms had better drying behaviour than young culms. Consequently, mature bamboo culms are more suitable for use in engineered composite materials.
  • Item
  • Item
    Characterization of Physical, Machining and Finishing Properties of Oil Palm Lumber: An Emerging Non-Timber Forest Product in Sub-Saharan Africa
    (International Journal of Emerging Technology and Advanced Engineering, 2008) Okai, Reynolds; Mitchual, J Stephen; Mensah, Prosper; Dzakpasu, K Raphael
    Environmental problems associated with the rapid depletion of the tropical forest have necessitated the need to look for alternative sources of timber supply. Compression parallel to grain tests, three-point static bending tests, machining tests and finishing characteristics of oil palm lumber, a non-timber forest product were conducted to determine its suitability for furniture production. A compression parallel to the grain of 13 N/mm2 , a modulus of elasticity of 2924 N/mm2 , and a modulus of rupture of 25 N/mm2 at 12% moisture content were obtained. The lower strength properties of oil palm lumber compared to conventional lumber suggest that oil palm lumber could be used for light load bearing products such as coffee tables, center tables, ceilings and wall panels. Planing and sanding operations produced rough surfaces with sharp raised grains which had piercing effect on the fingers. However, application of sanding sealer followed by sanding operations removed all the sharp raised grains, thereby resulting in production of smooth surfaces. Application of synthetic clear vanish at the final phase of the finishing process produced a very bright surface with a protective plastic-like film. It could therefore be concluded that oil palm lumber could be used for the production of light load bearing furniture products.
  • Item
    Physico-chemical characteristics and market potential of sawdust charcoal briquette
    (International Journal of Emerging Technology and Advanced Engineering, 2008) Akowuah, Joseph O; Kemausuor, Francis; Mitchual, J Stephen
    In the absence of the widespread distribution of modern cooking fuels in developing countries, efforts are being made to utilise biomass residues which abound in most of these countries. This is intended to replace portions of firewood and charcoal and thereby reduce the cutting down of forests for fuel purposes. Briquettes from agro-residues have therefore been promoted as a better replacement to firewood and charcoals for heating, cooking and other industrial applications in both urban and rural communities. This study sought to assess the physico-chemical properties of charcoal briquettes produced in Ghana and also establish demand for and willingness of potential users to substitute charcoal and firewood with a charcoal briquette. A laboratory experiment was conducted to determine the physico-chemical characteristics of the briquettes. This was done prior to the distribution of the briquette to potential users to collaborate their views or otherwise on the handling and burning characteristics of the charcoal briquette. A survey was undertaken a week later using questionnaires to access the willingness of the potential users to use the briquettes. Sixty respondents were purposively selected from households and the hospitality industry for the survey. Results of the physico-chemical assessment of the briquettes were as follows: length (75 to 120 mm), moisture content (5.7% dry basis), density (1.1 g/cm3 ), ash content (2.6%), fixed carbon (20.7%), volatile matter (71%) and calorific value (4,820 kcal/kg). Responses from the survey indicated that the briquette is easy to ignite, has a long burning time and has good heat output. Respondents also observed that the briquettes did not give off sparks and had less smoke and ash content as compared to the regular charcoal they often used. Finally, 93% of the respondents indicated their willingness to use the briquettes if the price was comparable to charcoal
  • Item
    Organizational issues and challenges of supervised industrial attachment of a technical and vocational teacher education program in Ghana
    (Asia‐Pacific Journal of Cooperative Education, 2009) Donkor, FRANCIS; Nsoh, STANISLAUS N.; Mitchual, STEPHEN J.
    The Technical and Vocational Teacher Education program of the University of Education, Winneba in Ghana, includes a compulsory supervised industrial attachment.  This gives student teachers the opportunity relate theory to practice and to enable them go out to prepare their students for success in further education and the workplace.  This paper which is part of a larger study that assessed the supervised industrial attachment focuses on organizational issues and the program’s challenges.  Data were collected from 13 lecturers, 90 students and 22 workplace supervisors through self‐ completion questionnaire.  The reported findings were based on four‐point Likert‐type items relating to organizational issues and challenges.  Data were analyzed using descriptive statistics, t‐test, ANOVA and Scheffe′s post hoc test.  The findings revealed dissatisfaction of stakeholders with weightings of assessment components, the practice of students finding their own placements, program duration, and lack of liaison officer.   Among the 10 items on organizational issues, only three produced statistically significant differences in respondents’ ratings.  The perceived challenges were lack of free access to machines and equipment, amount of money spent traveling to and from the workplace, and time spent on finding placement.  Among the five items on challenges, only one produced statistically significant differences in respondents’ ratings.  (Asia‐Pacific Journal of Cooperative Education, 10(1), 39‐56)
  • Item
    Spatial Planning and Climate Change Adaption in Coastal Regions: The Case of Vietnam1
    (International Federation of Surveyors, 2009) Boateng, Isaac
    Spatial planning in coastal regions has emerged as a major issue in the 21st century due to the potential impacts of the changing climate and the associated rising sea levels in coastal regions. This paper explores the potential impacts of climate change and the vulnerability of the coast of Vietnam based upon geodetic information and the present coastal development. It then discusses how sustainable spatial planning approaches could be used to reduce vulnerability to climate change and ensure sustainable coastal adaptation of Vietnam’s coastal zone. Based on a large-scale flood risk assessment, the study identified that non-structural approach could be used by Vietnam to adapt her low-lying coastline in the North and the South to climate change as this strategy enables vulnerable areas to be occupied for longer before eventual retreat. However, structural adaption policies could be pursued at the central coast which has high elevation and relatively hard geology. The paper revealed that sustainable and successful adaptation to climate change could be achieved if it is perceived as a process similar to spatial planning. It should be planed, implemented well in advance, monitored and evaluated before the occurrence of a natural disaster or an environmental change. Based on this, it recommended that Vietnam should develop and implement coastal adaptation policies now in order to forestalled huge impacts of future climate related disasters. The paper concludes that though coastal adaptation to climate change is a new phenomenon, it does apply key principles of spatial planning concepts and therefore recommended that spatial planning principles should be adopted for the development and implementation of sustainable coastal adaption policies to reduce the impacts of climate change.
  • Item
    Organizational issues and challenges of supervised industrial attachment of a technical and vocational teacher education program in Ghana
    (Asia‐Pacific Journal of Cooperative Education, 2009-10-01) Donkor, Francis; Nsoh, Stanislaus N; Mitchual, Stephen Jobson
    The Technical and Vocational Teacher Education program of the University of Education, Winneba in Ghana, includes a compulsory supervised industrial attachment.  This gives student teachers the opportunity relate theory to practice and to enable them go out to prepare their students for success in further education and the workplace.  This paper which is part of a larger study that assessed the supervised industrial attachment focuses on organizational issues and the program’s challenges.  Data were collected from 13 lecturers, 90 students and 22 workplace supervisors through self‐ completion questionnaire.  The reported findings were based on four‐point Likert‐type items relating to organizational issues and challenges.  Data were analyzed using descriptive statistics, t‐test, ANOVA and Scheffe′s post hoc test.  The findings revealed dissatisfaction of stakeholders with weightings of assessment components, the practice of students finding their own placements, program duration, and lack of liaison officer.   Among the 10 items on organizational issues, only three produced statistically significant differences in respondents’ ratings.  The perceived challenges were lack of free access to machines and equipment, amount of money spent traveling to and from the workplace, and time spent on finding placement.  Among the five items on challenges, only one produced statistically significant differences in respondents’ ratings.  (Asia‐Pacific Journal of Cooperative Education, 10(1), 39‐56
  • Item
    Assessment of supervised industrial attachment of a technical and vocational teacher education program in Ghana
    (Asia‐Pacific Journal of Cooperative Education, 2009-10-01) Donkor, Francis; Nsoh, Stanislaus N; Mitchual, Stephen J
    The Technical and Vocational Teacher Education program of the University of Education, Winneba in Ghana, includes a compulsory supervised industrial attachment (SIA). This gives student teachers the opportunity to relate theory to practice and to be well prepared upon completion to prepare their students for success in further education and the workplace. This paper which is part of a larger study that assessed the SIA program focuses on the attainment of program objectives and program usefulness. Data were collected from 13 lecturers, 90 students and 22 workplace supervisors through a self‐completion questionnaire. The reported findings were based on four‐point Likert‐type items relating to the attainment of program objectives (5 items) and program usefulness (5 items). Descriptive statistics, one‐ way analysis of variance at 0.05 level of significance and Scheffe′s post hoc test were used to analyze the data. The results showed that lecturers, students and workplace supervisors rated highly elements of program usefulness and the attainment of program objectives. Additionally, there was uniform agreement in the responses of respondents as there were no statistically significant differences in their ratings of all the items relating to attainment of program objectives and program usefulness except for their ratings regarding the opportunity for host organizations to reduce recruitment and training costs of workplace staff during attachment (Asia‐Pacific Journal of Cooperative Education, 10(1), 1‐17)
  • Item
    THE BEST PRACTICE FOR COASTAL ADAPTION PLANNING: A SURVEYOR’S PERSPECTIVE
    (Publication of FIG Commission 8 Working Group 8.4, 2010) Boateng, Isaac
  • Item
    Estimating the fluvial sediment input to the coastal sediment budget: A case study of Ghana
    (University of Portsmouth, 2011-08) Boateng, Isaac; Bray, Malcolm; Hooke, Janet
    Knowledge of fluvial sediment supply to the coastal sediment budget is important for the assessment of the impacts on coastal stability. Such knowledge is valuable for designing coastal engineering schemes and the de velopment of shoreline management planning policies. It also facilitates understanding of the connection between rivers in the hinterland and adjoining coastal systems. Ghana's coast has many fluvial sediment sources and this paper provides the first quantitative assessments of their contributions to the coastal sediment budget. The methods use largely existing data and attempt to cover all of Ghana's significant coastal rivers. Initially work was hindered by insufficient direct measured data. However, the problem was overcome by the application of a regression approach, which provides an estimated sediment yield for non-gauged rivers based on data from gauged rivers with similar characteristics. The regression approach was effective because a regional coherence in behaviour was determined between those rivers, where direct measured data were available. The results of the assessment revealed that Ghana's coast is dissected by many south-draining rivers, stream and lagoons. These rivers, streams and lagoons supply significant amounts of sediment to coastal lowlands and therefore con tribute importantly to beaches. Anthropogenic impoundment of fluvial sediment, especially the Akosombo dam on the Volta River, has reduced the total fluvial sediment input to the coast from about 71×106 m3 /a before 1964 (pre-Akosombo dam) to about 7×106 m3 /a at present (post-Akosombo dam). This sharp reduction threatened the stability of the east coast and prompted an expensive ($83 million) defence scheme to be implemented to protect 8.4 km-long coastline at Keta. Sections of Ghana's coast are closely connected to the hinterland through the fluvial sediment input from local rivers. Therefore, development in the hinterland that alters the fluvial sediment input from those local rivers could have significant effects on the coast. There is the need, therefore, to ensure that catchment management plans and coastal management plans are integrated or interconnected
  • Item
    GIS assessment of coastal vulnerability to climate change and coastal adaption planning in Vietnam
    (Springer, 2011-09-21) Boateng, Isaac
    t Vietnam's coastal zone provides a diverse range of natural resources and favourable conditions for social and economic development. However, its coastal ecosystems are highly vulnerable, due to several natural coastal hazards, over-exploitation and other human activities. In spite of diverse interventions, Vietnam's coastal zone continues to experience signifi- cant damage from floods, erosion and typhoons. These hazards are being intensified by climate change and associated rising sea levels. This paper assesses the potential vulnerability of Vietnam's coast to climate change and discusses possible adaptation policies and plan to reduce the impacts. GIS analysis was used for the assessment of coastal vulnerability. Related literature was reviewed to develop detailed understanding of coastal adaptation to climate change. Adaptation policies and plans were appraised to identify potential coastal adaptation policies and plans that could be adapted by Vietnam. It was identified that vulnerability of the coastal zone of Vietnam could not be attributed only to climatic factors, but also to the physical condition of the coastline. Much of Vietnam's coastline, particularly, areas around the Red River delta and the Mekong River have elevations below 1 m. These coastlines are largely developed and serve as economic centres of the country, which makes the coast more vulnerable to climate change and the rising sea level. The paper concluded I. Boateng (El) School of Civil Engineering and Surveying, University of Portsmouth, Portland Building, Portland Street, Portsmouth POI 3AH, United Kingdom e-mail: Isaac.boateng@port.ac.uk that a non-structural approach (coastal buffer zones, building houses on stilts, storm warning systems, growing of flood-resistant crops and elevated storm shelters with medicine and food storage) could be used by Vietnam to adapt her low-lying coastline around the two deltas to climate change as this strategy enables vulnerable areas to be occupied for longer before eventual retreat. However, for these policies to be successful, it should be planned, implemented well in advance, monitored and evaluated o
  • Item
    Analyses of Bending Moment Effect on the Floors of Modeled High Rise Buildings
    (Research India Publications, 2012) Danso,Humphery
    Computer modeling aims at transforming the design process of buildings worldwide from the use of 2D to 3D, 4D and 5D design and coordination technologies. To investigate realistic values of bending moment and normal forces, a full three-dimension (3D) analysis is needed in order to obtain correct values, therefore the state of stress within a floor is more complex, in addition to the normal stresses due to bending which is huge and in most cases must be considered if failure is to be avoided. The purpose of this research is to study and compare the effect of bending moment on floors of modeled high rise buildings on elastic ground and firm ground. The research design was exploratory which made use of Complex Program Lira to design and calculate 18-storey residential buildings. The results indicate that for both models the maximum bending stress occurred at the first floors whiles the minimum bending stress occurred at the top floors. The bending stresses from second floor to the top floor are the same for each model. The model with elastic base foundation has high bending stress as compared to the model with firm base foundation by 30% for first floors and 28% for the subsequent floors. It could therefore be concluded that bending moment effect on the floors was greater in the model with elastic base than the model with firm base.
  • Item
    Construction Workers’ Satisfaction with Work Provision Requirement Dimensions in Ghana’s Construction Industry
    (International Journal of Engineering and Technology, 2012) Danso, Humphery.
    This paper, sought to empirically assess and analyze workers’ satisfaction with different dimensions of work provision requirement of the construction industry in Ghana. It involved a cross-sectional survey that used a self-administered structured questionnaire administered to five hundred respondents of building construction workers. The findings indicate that though workers are satisfied with some work provision requirement dimension items significantly, most of the workers are very dissatisfied with working environment and work benefit of the work provision requirement in Ghana. The management of construction firms in Ghana and policy makers are called upon to focus and redirect attention and effort to ensuring that work provision requirement that workers are dissatisfied with are improved significantly to meet workers expectations. The paper contributes to the general body of knowledge in the area of workers’ satisfaction in developing countries particularly in Ghana’s construction industry. Theoretical and managerial implications are discussed.
  • Item
    An assessment of the physical impacts of sea-level rise and coastal adaptation: a case study of the eastern coast of Ghana
    (University of Portsmouth, 2012) Boateng, Isaac
    Sea-level rise is a major coastal issue in the 21st century because many of the world’s built assets are located in the coastal zone. Coastal erosion and flooding are serious threats along the coast of Ghana, particularly, the eastern coast where the Volta delta is located. Past human interventions, climate change and the resultant rise in sea-levels, increased storm intensity and torrential rainfall have been blamed for these problems. Accelerated sea-level rise and storm surge pose serious threat to coastal habitat, bio diversity and socio-economic activities in the coastal zone of Ghana and elsewhere. There is the need for an holistic assessment of the impacts of sea-level rise on the coast zone in order to formulate appropriate adaptation policies and strategies to mitigate the possible effects. Using the eastern coast of Ghana as a case study, this paper assesses the physical impacts of accelerated sea level rise and storm surge on the coastal environment. It evaluates adaptation policies and plans that could be implemented to accommodate the present and any future impacts. Field investigation and Geographic Information System (GIS) are among the methods used for the assessment. The outcome of the assessment has provided compre hensive knowledge of the potential impacts of accelerated sea-level rise and storm surge on the eastern coast. It has facilitated identification of management units, the appraisal of alternate adaptation policies and the selection of the best policy options based upon the local conditions and environmental sustainability. Among other things, this paper reveals that the eastern coast of Ghana is highly vulnerable to accelerated sea-level rise and therefore, requires sustainable adaptation policies and plans to manage the potential impacts. It recommends that various accommodation policies, which enable areas to be occupied for longer before eventual retreat, could be adapted to accommodate vulnerable settlements in the eastern coast of Ghana.
  • Item
    Performance characteristics of enhanced soil blocks: a quantitative review
    (Talor&Francis, 2012) Danso, Humphery
    Several studies have focused on improving the properties of soil blocks/bricks due to perceived and real strength and durability limitations. A review of 56 published studies is presented on the effect of stabilization on the performance characteristics of soil blocks. The review found that few studies have been conducted on durability properties of enhanced soil blocks as compared with physico-mechanical properties. Fibre-enhanced soil blocks tended to have peak performance with an optimal content that achieved maximum performance. The maximum performance improvement was generally less than a doubling of the strength of the soil without the fibres. Binders showed a continual improvement with greater concentrations, so much greater improvements can be obtained if the economic and social costs can be justified. Both fibres and binders have variable performance on water absorption with both reductions and increases possible. Generally, both fibre and binder inclusion in soil blocks enhance the performance characteristics of the blocks. Binders are typically more effective on a mass-fraction basis. However the supply of fibres is usually at a lower cost and a reduced environmental impact, and therefore may have a better performance on a per-cost or per-impact basis.
  • Item
    DEVELOPMENT OF KILN-DRYING SCHEDULES AND WITHIN TREE VARIABILITY IN THE PHYSICAL PROPERTIES OF TWO LESSER-KNOWN TIMBER SPECIES IN GHANA
    (College of Agriculture and Natural Resources, 2012) Effah, Bernard
    Decreasing supply of most commercial wood as raw material inspires the forest products industry to look for other wood species which have similar or greater commercial values but are not currently utilized by the forest products industry. Wood is versatile and the oldest building material used by man. But there is limited knowledge about the properties of a large proportion of timber-grade wood species. Proper utilization of a particular wood species must be based on both basic properties and processing properties. Drying is one of the most important processing properties, because a proper drying process will be the main key to utilize efficiently and ensure high quality wood products. Cola nitida (Bese) and Funtumia elastica (Funtum) are two lesser- known species in Ghana that are not used for commercial timber purposes. The overall objective of this study was to develop kiln-drying schedules for Cola nitida (Bese) and Funtumia elastica (Funtum), as well as assess the variability of the physical properties as the basis for determining the potential uses that may encourage the utilization and promotion of these lesser known species. The basic properties were determined based on British Standard 373 (1957), whiles the drying schedules were determined using the quick drying test method developed by Terazawa (1965). The main statistical tools used were Descriptive Statistics and Analysis of Variance (ANOVA). Variation in physical properties was analyzed within the trees of the two species. Three trees each per species were used in the study. Results of the study showed that initial moisture content were 66.6% and 79.4% for Cola nitida and Funtumia elastica respectively. The basic density of Cola nitida was 623.8 kg/m3 and 499.6 kg/m3 for Funtumia elastica. According to TEDB (1994), Cola nitida is a Medium-Heavy species and Funtumia elastica a Medium Weight species. Mean total tangential shrinkage from green to oven-dry was 7.25 and 6.78% for Cola nitida and Funtumia elastica, respectively. Mean partial tangential shrinkage from green to 12% MC is very small (under 2.5%) for Cola nitida and medium (4.0-5.5%) for Funtumia elastica. The corresponding mean partial radial shrinkage values also showed that shrinkage was very small (under 1.0%) for Cola nitida and medium (2.0–3.0%) for Funtumia elastica. The shrinkage values for the two species compared favourably with those of some locally used species for timber production (like Scottellia coriacea and Lannea welwitschii), and therefore could be considered suitable for timber utilization. The drying schedules also comformed to those of Sterculia rhinopetala and Alstonia boonei as proposed by Ofori and Brentuo (2010b). Checks in the early stages of drying were less severe in both Cola nitida and Funtumia elastica samples (Class 3). There were no honeycombing (Class 1) in both Cola nitida and Funtumia elastica species. There was no deformation (Class 1) in both Cola nitida and Funtumia elastica species. Experimental dry kiln schedules for lumber of thickness up to 38 mm corresponding to two Madison schedules were proposed: Cola nitida (T10- C4) and Funtumia elastica (T10 – D4). The results of the analysis of variance (ANOVA) revealed that the three axial sections of the trees showed significant differences at 5% probability level (p < 0.05). The technical values of the study results compared favourably with technical values of some locally used species for timber production (like Scottellia coriacea and Lannea welwitschii), and therefore could be considered suitable for timber utilization.
  • Item
    Assessment of the Awareness of Structural Computer Aided Design Programs of Universities in Ghana
    (EuroJournals Publishing, 2012) Danso,Humphery
    The few past decades have seen the use of Computer Aided Design (CAD) software application in the area of built environment. In view of this, more CAD software programs have been developed to design and analyze buildings and structures. This makes CAD an important part of the design and construction industry. This paper reports the assessment of the level of awareness and usage of structural CAD programs by students in Universities offering Civil Engineering and related programs in Ghana. The design used for this study was survey which relied on questionnaire to generate data for the analysis and discussions. The study established that the respondents knew the General CAD programs of which 69.9% knew AutoCAD. However, majority (64.8%) of the respondents did not know about any of the Structural CAD software packages, indicating a low awareness level of Structural CAD software programs. Recommendations are made for the inclusion of Structural CAD programs in the courses of the Universities offering Civil Engineering and related programs in Ghana.