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Strength grading of timber offers a number of advantages both to the designer and the supplier of timber. This study reveals characterization and grading of Nigerian grown Eku (Brachystegia eurycoma) timber using BS 5268 (2002). Specimens used in the experiment were obtained from sawmills in Kwara State, Nigeria. The samples were seasoned naturally...
Context in source publication
Context 1
... plates below show the test specimen arrangement for various mechanical/strength tests carried on the timber specie using Testometric Universal Testing Machine (UTM) of capacity 300kN in Agricultural and Biosystems Engineering Laboratory, University of Ilorin, Nigeria. Table 1 shows the statistical results for Brachystegia eurycoma such as the minimum, maximum, mean, standard deviation, coefficient of variation, 95% and 99% confidence limit of density at experimental moisture content are equally shown in the table. The mean value of the density was 1148.25kg/m 3 with standard deviation and coefficient of variation of 62.29kg/m 3 and 5.43% respectively. ...
Citations
... According to [7], Nigeria's forest reserves cover roughly 10 million hectares, or 10% of the country's total land area, which is estimated to be 96.2 million hectares. In contrast, Nigeria has an abundance of lumber [8] that, if used appropriately, will be of great advantage to the nation in terms of lowering the cost of construction [9,10,11]. ...
... The timbers studied are Brachystegia eurycoma (popularly called Eku in South Western Nigeria), Entandrophragma cylindricum (Sapele) and Gmelina Arborea (Melina). Brachystegia eurycoma is called by different names by different tribe in Nigeria, such as Okuen (Edo), Okung (E k), Achi (Igbo) [14], Dewen (Bini), Akpakpa or Apaupan (Ijaw) and Eku or Akalado (Yoruba) [10]. It is economically valuable tree mostly grown in tropical rain forest of West Africa [15]. ...
... It is a large tree and its branches are spreading in nature and are either irregular or twisted in shape [14]. Studies on Brachystegia eurycoma includes determination of its physical properties [15], Isolation, Characteristics and anti-oxidant activity of a Furo-Chromen-4-one from its seed [16], anti-diarrheal activity of the stem bark extract [14] and its characterization and grading [10]. However, none has compared the age and strength of the timber. ...
Timber is a material used for structural purposes in construction. Therefore, it is crucial to understand the characteristics of timber, particularly its strength and the factors that influence it. In this study, timbers studied were Brachystegia eurycoma (Eku), Entandrophragma cylindricum (Sapele) and Gmelina Arborea (Melina). A personal visit to the forest where they were freshly retrieved allowed for the collection of samples of timber from varied ages. By counting the number of annual growth rings, which are a combination of early wood and late wood, it was possible to establish the age of the wood. The acquired samples were cut to standard sizes in accordance with BS 373 1957 (Imprint 1999), 20mm X 20mm X 60mm for determining the maximum compressive strength parallel to grain, 20mm X 20mm X 300mm for determining the bending strength, and 20mm X 20mm X 20mm for static stress strength. Results obtained showed that Eku is better in compressive strength and Sapele is worthier in bending strength. The maximum compressive strength value was 49.31kN/m ² (at 45years), 45.89kN/m ² (at 60years) and 11.30kN/m ² (at 25years), maximum bending strength were 187.55kN/m ² (at 35years), 278.79kN/m ² (at 70years) and 176.36kN/m ² (at 20years) and shear strength were 10.05kN/m ² (at 50years), 9.22kN/m ² (at 70years) and 10.91kN/m ² (at 25years) for Eku, Sapele and Melina timbers respectively. In conclusion, it was determined that the strength of wood is influenced by the age of the wood.
... Nigeria is one of the countries that have timber in surplus quantity (Jimoh et al., 2017a natural resource is properly utilized, it will be of immense benefit to the country in terms of reduction in the cost of construction (Aguwa, 2012;Rahmon, et al., 2017;Ibitolu and Jimoh, 2017). Different wood species have different strength characteristics, and also within a species, these characteristics may vary. ...
... The need for local content in the construction of engineering infrastructure is now a serious engineering challenge in Nigeria. Due to vast quantities of local raw materials, which must be processed and used for cost-effective structures (Aguwa, 2016;Rahmon et al., 2017). ...
The effect of cassava peel ash (CPA) on dessication-induced volumetric shrinkage of black cotton
soil (BCS) using three different compactive efforts was investigated. This paper presents the
laboratory investigation results when the CPA and moulding water contents are varied; 0, 4, 8, 12,
16, 20 and 24% CPA contents at 2% dry, Optimum Moisture Content (OMC), 2% wet and 4% wet
of optimum moisture content (OMC) using British Standard Light (BSL), British Standard Heavy
(BSH) and West African Standard (WAS) compactive efforts. Index properties, volumetric
shrinkage Strain (VSS) and Scanning Electron Microscopy (SEM) tests were carried out on natural
CPA treated black cotton soil. From the results, there are noticeable changes in the index
properties. The Plasticity Index (PI) produced minimum value of 11% at 16% CPA content, at the
same blend; the maximum values of MDD are 17.9 kN/m3
(BSL), 18.9kN/m3
(BSH) and
18.1kN/m3
(WAS), the minimum values of OMC are 13.4% (BSL), 9.8% (BSH) and 15.3%
(WAS). The outcome of the investigation revealed that at 16% CPA treatment, values of VSS
reduced by 73% (BSL), 92% (BSH) and 74% (WAS). SEM analysis also showed improved
bonding between the soil grains and inter-grain porosity closed up at 16% CPA treatment.
... Nigeria is one of the countries that have timber in surplus quantity (Jimoh et al., 2017a natural resource is properly utilized, it will be of immense benefit to the country in terms of reduction in the cost of construction (Aguwa, 2012;Rahmon, et al., 2017;Ibitolu and Jimoh, 2017). Different wood species have different strength characteristics, and also within a species, these characteristics may vary. ...
... The need for local content in the construction of engineering infrastructure is now a serious engineering challenge in Nigeria. Due to vast quantities of local raw materials, which must be processed and used for cost-effective structures (Aguwa, 2016;Rahmon et al., 2017). ...
BSTRACT
This study used the application of Geographic Information System (GIS) to analysed spatial
accessibility to Public Secondary Schools (PSSs) education in Osun West Senatorial District
(OWSD), Nigeria with a view to providing information that could enhance future secondary
school education planning and development. The specific objectives are to determine the
location of public secondary schools in the district and examine the area coverage.
Data for this study were obtained through direct field observation using the Global Positioning
System (GPS) to identify and examine coverage areas of these 116 PSSs in the study area,
settlements with PSSs were stratified into three categories based on population density: suburb
(less than 10,000 people), semi-urban (between 10,000-19,999 people) and urban (20,000
people and above). The data acquired were analysed using GIS and descriptive statistics.
Findings of the study established that across the settlements categories that PSSs at the buffer
of 1km Radius (Rs), majority (81.8%) were clustered in the urban while majority (20%) and
(70.0%) in both semi-urban and suburb were dispersed. Findings further revealed that majority
PSSs at the buffer of 2km Rs, in urban (64.8%) were clustered while 21.4% and 71.4% were
dispersed in the semi-urban and suburb. Moreover, findings showed that PSSs were clustered
at the buffer of 3km Rs (63.3%) in the urban and dispersed (23.1% and 69.2%) in both semi-
urban and suburb. Furthermore, it is evident from the findings that PSSs at the buffer of 4km
Rs, majority (55.9%) were clustered in the urban while majority (35.7% and 56.1%) in the
semi-urban and suburb were dispersed. The study concluded that PSSs were not evenly accessible in OWSD. It is therefore recommends that, Government, stakeholders and private
investors should come together to make PSSs education available to all category of settlements.
Keywords: Public Secondary Schools, Spatial Planning, Accessibility, Settlements Categorization
... Nigeria is one of the countries that have timber in surplus quantity (Jimoh et al., 2017a natural resource is properly utilized, it will be of immense benefit to the country in terms of reduction in the cost of construction (Aguwa, 2012;Rahmon, et al., 2017;Ibitolu and Jimoh, 2017). Different wood species have different strength characteristics, and also within a species, these characteristics may vary. ...
... The need for local content in the construction of engineering infrastructure is now a serious engineering challenge in Nigeria. Due to vast quantities of local raw materials, which must be processed and used for cost-effective structures (Aguwa, 2016;Rahmon et al., 2017). ...
... Nigeria is one of the countries that have timber in surplus quantity (Jimoh et al., 2017a natural resource is properly utilized, it will be of immense benefit to the country in terms of reduction in the cost of construction (Aguwa, 2012;Rahmon, et al., 2017;Ibitolu and Jimoh, 2017). Different wood species have different strength characteristics, and also within a species, these characteristics may vary. ...
... The need for local content in the construction of engineering infrastructure is now a serious engineering challenge in Nigeria. Due to vast quantities of local raw materials, which must be processed and used for cost-effective structures (Aguwa, 2016;Rahmon et al., 2017). ...
... Alamu, and Agbeja (2011) stated that forest reserves take possession of approximately 10 million hectares, standing for about 10% of a land area of approximately 96.2 million hectares in Nigeria. If this natural resource is properly utilized, it will be of immense benefit to the country in terms of reduction in the cost of construction (Aguwa, 2012;Rahmon, et al., 2017;Ibitolu and Jimoh, 2017). Different wood species have different strength characteristics, and also within a species, these characteristics may DOI:10.36108/laujoces/0202/40(0170) ...
... The need for local content in the construction of engineering infrastructure is now a serious engineering challenge in Nigeria. Due to vast quantities of local raw materials, which must be processed and used for cost-effective structures (Aguwa, 2016;Rahmon et al., 2017). Construction activities based on these locally available raw materials are major steps towards industrialization and economic independence for developing countries. ...
As a result of increase in population growth and urbanization, the demand for timber in construction industry has exponentially increased. Common and popular timber in the industry do not meet up with the high demand and attention has been shifted to unpopular timber species such as Bush mango (Irvingia gabonensis) and Ire (Funtumia elastica) but their properties are yet to be fully researched and documented. This research therefore aimed at characterizing and grading of two less-used timber species in Kwara State, Nigeria for structural applications. The selected timber species were obtained from Irewolede Sawmill in Ilorin, Kwara State and various test specimens were prepared according to the BS 373: 1957 using Small Clear Size Specimens of Timber. A total of 200 specimens free from visible defects were used for the determination of the strength properties using the Universal Testing Machine of 300 kN capacity at the Department of Agricultural and Biosystems Engineering, University of Ilorin in accordance with BS 373: 1957 (revised in 1999). It was revealed that Bush mango and Ire had average moisture contents of 13.95 and 12.71%, respectively. For density classification, Bush mango and Ire were classified as medium and light wood, respectively. Bush mango and Ire were therefore graded according to NCP 2 (1973) and BS 5268 (2002) and assigned to their corresponding strength classes. Hence, Bush mango can be applied as bridge beam and railway sleepers while Ire can be used for lightweight furniture.
... Structural timber is the timber used in framing and load-bearing structures, where strength is the major factor in its selection and use (Aguwa, et al., 2015;Jimoh, et al., 2017). Most woods used in the building construction are softwoods but in structures like bridges and railway sleepers, hardwoods are specially used (Karlsen and Slitskouhov, 1989;Rahmon, et al., 2017). The main characteristic of these timbers under investigation is their buckling characteristics when subjected to compressive load (Jimoh, et al., 2018). ...
Structural reliability was examined on the lesser-used species such as Arere (Triplochiton scleroxylon) and Emi (Vitellaria paradoxa) which can be good substitute to the well-known species. The strength and physical properties of these timber species were determined to predict the suitability of the species as structural material. Twenty lengths of timber species of 50 x 50 mm cross-section were purchased from timber market in Ilorin, Nigeria. The prevailing environmental conditions during the test were 31oC and 64% relative humidity. The properties tested included; air dry density, moisture content and compressive strength parallel to grain of twenty (20) test specimens each of lengths, 200, 400, 600 and 800 mm done in accordance with the British Standard BS 373 (1957). Mean air-dried moisture content for Arere and Emi were 14.48 and 15.89 % respectively. Mean density of Arere and Emi were 514.32 and 1147.75 kg/m3 respectively. The reliability index of Arere and Emi timber species are 0.64 and 0.65 respectively for a service life of 50 years, assuming all other design conditions are met
... Nigeria is one of the countries that have timber in surplus quantity (Jimoh et al., 2017a natural resource is properly utilized, it will be of immense benefit to the country in terms of reduction in the cost of construction (Aguwa, 2012;Rahmon, et al., 2017;Ibitolu and Jimoh, 2017). Different wood species have different strength characteristics, and also within a species, these characteristics may vary. ...
... The need for local content in the construction of engineering infrastructure is now a serious engineering challenge in Nigeria. Due to vast quantities of local raw materials, which must be processed and used for cost-effective structures (Aguwa, 2016;Rahmon et al., 2017). ...
This paper used the Institutional Analysis and Development (IAD) framework in tandem with
Knowledge Management (KM) tools and Robert Owen’s Principles of Industrialisation (ROPI)
to analyze the missing links in developmental strategies in Africa. The missing links resonate
around the neglect of the potentials and capabilities of endogenous knowledge tools and
techniques on the one hand and the problem of disconnect between African governments,
universities, private/industrial sector and peasant farmers on the other hand. The type of
resources within an environment, to a large extent and other things being equal, determines the
fortunes of the people in that environment. It is on this note that this paper argues that Africa
is endowed with diverse environmental and natural resources upon which African universities
should base their intellectual inquiry for the application of endogenous knowledge,
entrepreneurship and appropriate technology in turning raw materials into products rather being
an importing continent. This paper shows findings of several studies and adopts pragmatic and
problem-solving models to demonstrate principles and practices needed to make adaptive
education resolve technologically-related environmental challenges in Africa. The paper,
thereafter, charts a course of action that could be taken to ensure that African universities
become “organic” in their activities and use endogenous knowledge as agents of change to
impact positively on economic developmental transformation. It is in the light of this exigency
that this paper suggests African Endogenous Knowledge Development Model and the
mechanism for taking theories to the streets for self-reliant development and technologically
inclined and environmentally friendly community in Africa.
... Nigeria is one of the countries that have timber in surplus quantity (Jimoh et al., 2017a natural resource is properly utilized, it will be of immense benefit to the country in terms of reduction in the cost of construction (Aguwa, 2012;Rahmon, et al., 2017;Ibitolu and Jimoh, 2017). Different wood species have different strength characteristics, and also within a species, these characteristics may vary. ...
... The need for local content in the construction of engineering infrastructure is now a serious engineering challenge in Nigeria. Due to vast quantities of local raw materials, which must be processed and used for cost-effective structures (Aguwa, 2016;Rahmon et al., 2017). ...
Description
Installation of capacitors in power networks are generally used for the improvement of the network power factor, improvement of the voltage profile and the voltage stability index, maximizing flow through cables and transformer, and minimization of total power loses due to the compensation of the reactive component of power flow. These benefits depend to a very large extent on the size and location of the capacitor in the radial distribution network as wrong placement can lead to the opposite effects. Furthermore, the appropriate placement of capacitors will reduce the total capacitor costs and the running expenses of Distribution Companies (DISCOs). In this paper, the problem of optimal placement and sizing of capacitor in the buses of Nigerian distribution network is addressed. The proposed methodology uses the Cuckoo Search Algorithm (CSA) to determine the size and the location satisfying the operating constraints. To demonstrate the capability of the proposed method, it was tested Imalefalafia 32 bus radial distribution network of the Ibadan Electricity Distribution Company (IBEDC). The simulation results obtained with compensation was compared with that of the base case (without compensation) and found to be encouraging.
... Alamu, and Agbeja (2011) stated that forest reserves take possession of approximately 10 million hectares, standing for about 10% of a land area of approximately 96.2 million hectares in Nigeria. If this natural resource is properly utilized, it will be of immense benefit to the country in terms of reduction in the cost of construction (Aguwa, 2012;Rahmon, et al., 2017;Ibitolu and Jimoh, 2017). The strength of a timber depends on its species and the effects of certain growth characteristics (Jimoh et al., 2017b). ...
... The need for local content in the construction of engineering infrastructure is now a serious engineering challenge in Nigeria. This is because vast quantities of local raw materials, which must be processed and used for cost-effective abound (Aguwa, 2016;Rahmon et al., 2017;Zziwa et al., 2016). Construction activities based on these locally available raw materials are major steps towards industrialization and economic independence for developing countries. ...
Broad range of research works have been carried out over the past few years and these have resulted in
comprehensive information on materials properties of various species of timber in Nigeria. There is still
research gap to cover many useful but unpopular timber species, therefore this research work is meant at
characterising two commonly used timber species in Nigeria; Isoberlinia doka (Babo/Doka) and
Anogeissus leiocarpus (Ayin) for structural use as well as comparing their properties with other known
timber species. The logs of wood used were obtained from Irewolede Sawmill, from where tests specimen
were prepared in accordance with BS 373:1957. A total of 240 test specimens were prepared from the
timber species and Laboratory tests were carried out on these specimens using 100 kN Universal Testing
Machine (UTM) at the National Centre for Agricultural Mechanization (NCAM), Ajase Ipo Road, Ilorin,
Kwara State, to determine some of the physical and mechanical properties of the timber species. The
strength properties tested includes: bending strength (MOR), modulus of elasticity (MOE), tensile strength,
shear strength, compression strength (both parallel and perpendicular to grain) and cleavage strength while
the physical properties tested include moisture content, specific gravity, and density. The results obtained
show that the timber species are hardwood of higher strength classes (between strength classes D30 – D70)
when compared with BS 5268:2002 whereas, Ayin is stronger than Babo timber species according to NCP
2:1973.
