Study on the Bending Strength of Solid and Glue-Laminated Timber from Three Selected Nigerian Timber Species

Structural timber is desirable for lightness, aesthetics and environmental friendliness. However harnessing timber for structural application can be daunting. Over decades, developed societies modified their sawn timber species by way of gluing in the forms of glued laminated beams and columns. In Nigeria, sawn timber is yet to be explored along these lines. This paper therefore assessed the suitability of Funtumia africana, Alstonia congensis and Antiaris toxicaria Nigerian timber species in the production of glue- laminated timber elements using polyvinyl acetate glue.  The glueability, physical and mechanical properties of solid and glue-laminated species were assessed and compared.  Bending strength and characteristic values of bending strength were determined. Results showed that the timber species were glueable and bending strength across the species was 65.22 N/mm2 vs 36.44 N/mm2; 26.15 N/mm2 vs 25 N/mm2; 14 N/mm2 vs 20 N/mm2 in solid vs glued laminated Funtumia Africana, Alstonia congensis and Antiaris toxicaria beams respectively in edge wise bending. The glued laminated elements across the species developed 55%, 95% and 143% of the solid wood strength. It was shown that the timber species were structurally glueable using polyvinyl acetate glue. The study has shown that the bending strengths of glue-laminated Nigerian timber species were of structural significance given the bending strength of 36.44 N/mm2, 25 N/mm2 and 20 N/mm2 in Funtumia africana (Ire), Alstonia congensis(Awun) and Antiaris toxicaria (Oriro). Keywords: Glueability, Glued laminated timber, Nigerian timber species, bending strengt

Evaluation of Bottle Bricks Walls Using Polyethylene Terephthalate (pet) Bottle as Bricks

There has been a considerable imbalance between the availability of conventional building materials and their demand in the recent past. On the other hand, the plastic waste is abundantly available and the disposal of waste Polyethylene Terephthalate Plastics (PET) is a big challenge, as repeated recycling of PET bottles poses a potential danger of being transformed and only a small proportion of PET bottles are being recycled. In this work an attempt has been made to access material for building walls in term of using pet bottles bricks in respect to using different filer material and test their suitability and also experimenting their compressive strength. This research identifies the various suitable materials for making bottles brick and make use of reviewed paper, relevant literature, archival data and material inspection as a method of study. The solution to finding the physical properties of bottle brick was carried out through collecting data and information through scrutinize material inspection and literature reviewing. This research concerns with subjective assessment of attitudes, qualities and behaviour of different material filled in PET bottles for making PET bottle brick walls. Also these suitable samples were collected and analyzed by experimenting the compressive strength of each of material filled in each PET bottle. At the end, it concluded that different factor affects the use of suitable filler such as availability of the material, cost of material among others. PET bottle brick has advantages such as high strength, low cost, load capacity, reducing waste and energy efficiency, PET bottle bricks can be more effective compared to some conventional wall building materials such as brick, sandcrete block and ceramic block

Assessment of Renewable Sources of Energy for Residential Estate in Lagos State

The study investigated the use of renewable energy sources for residential estates in Lagos state; identified the available energy sources in the study area, determined the factors influencing the choice and utilization of renewable sources in the study area and examined the level of satisfaction derived from the chosen energy source by residents of Lagos state. The study was aimed at investigating the possibility of making energy available for residential estates dwellers from renewable energy sources so as to enhance uninterrupted energy supply and promote sustainability. To achieve the aim and objectives of the study, both primary and secondary data were used. The study made use of primary data collected by administration of e-questionnaire (google form) to building users. Data collected included energy source used by residents, the level of awareness of residents about various renewable sources, average amount of money spent on energy monthly, daily hours of energy supply, level of satisfaction derived from energy sources used. Data collected were analyzed using Statistical Package for Social it was analyzed using frequencies, mean score and tables. The result from the sources of energy used by residents in Lagos state revealed that 74% of buildings make use of generators alongside the energy provided from national grids. The result from the number of hours of energy supply daily revealed that residents only have access to electricity being an end use of energy for maximum of 8 hours. The level of awareness of residents revealed that 51.7%, 21.2%, 17.2%, 10.3%, 17.7% and 30.5% of the respondents are well informed about a possibility of generating energy from solar, wind, biomass, geothermal, biogas, and hydropower respectively. To promote the use of energy generated from renewables, the study made recommendations for intensified awareness schemes on the socioeconomic and environmental benefits of renewable energy sources, adequate investment in critical areas of renewable R&D and policy adjustments to create an investor friendly environment to attract greater renewable energy investment

Assessing the Mechanical Performance of Ternary Blended Cement Concrete Incorporating Periwinkle Shell and Bamboo Leaf Ashes

The study investigates the mechanical properties of concrete incorporating Periwinkle Shell Ash (PSA) and Bamboo Leaf Ash (BLA) as cementitious binders. Concrete cube (100mm) prepared from a standardized prescribed mix of 1:2:4, batch by volume was taken as the reference mix. The cement component in the reference mix was replaced with combined % weight of periwinkle shell ash (10-30%) and bamboo leaf ash (10% fixed) given five blended mixes. Water-cement ratio of 0.60 was adopted for the reference and blended mixes. A total of 144 cube specimens were evaluated for compressive and tensile splitting strength at four curing ages up to 56 days. The results indicated that the compressive strength generally increases with curing age, and that the mix containing 80% cement-10%PSA-10%BLA, outperformed that of the reference mix at 28 and 56 days. The tensile splitting strength increase with curing age and decreases as the % weight of PSA increases from 15% to 30%. A higher tensile splitting strength value was attained with mix 2 than the reference mix at 14, 28 and 56 days.  The regression equation for the strengths relationship was obtained as FSP = 0.141 (Fcu) 0.873. The study concluded that mix 2 proportion is adequate for the production of ordinary structural mix concrete. Keywords: periwinkle shell ash, bamboo leaf ash, blended cement concrete, compressive strength, tensile Splitting strengt

Assessing the Employee Well-Being and Performance in Small-Sized Construction Organization

Performance in paid work has for many years been studied as an important form of individual and group behavior, with researchers and practitioners often aiming for its enhancement through job design, staff selection and development, or shaping managerial style and organizational culture. In parallel with this interest in performance, psychologists in employment settings have also worked to understand the sources and consequences of well-being, motivation and performance. These three variables are examined together in the assessing the employee well-being in small-sized construction organization in Ekiti State. Employee well-being is considered as an important tool for enhancing worker’s performance and construction sector is not an exception. It has been empirically established that well-being has positive impact on construction worker’s performance. Moreover, empirical studies have shown that performance in the sector has been decreasing globally. This study therefore aims at understand the demanding working environment of the construction industry and the factors which lead to employees being troubled. The researcher was of the opinion that an improved well-being of employees can significantly improve the organization productivity. Quantitative research design was employed with same questionnaire administered on the population covered. Random sampling techniques were used to select small-sized construction organization sampled from a selected population in Ekiti State, Nigeria. Purposive sampling was used to administer questionnaires to various employees. 75questionnaires were administered to employee collectively and 70 was filled and returned which constitute 93.3% success rate. Questionnaire was designed in Likert scale of 1-5. Analysis was done by statistical packages for social sciences version 17. Descriptive statistics which include mean percentile and tables were used to present the data. One Way Analysis of Variance was used to determine whether there is relationship between well-being and organization performance. Data analysis and results on the factors affecting small-sized construction organization employee well-being indicates that there is a statistically significant linear relationship between well-being and performance. The result also revealed that there is a positive and significant relationship between well-being and employee’s performance which reinforces the reinforcement and expectancy theory of remuneration especially the concept of Thorndike’s Law of Effect meaning a response followed by a reward is more likely to recur in the future. The study concluded that well-being has impact on employees and organization performance and recommend that the employers of labor both private and government must not take the well-being of their employees for granted because it will result in low productivity

Strength Characteristics of Rice Husk and Corn Cob Ash Blended Cement Concrete

The study investigates the mechanical properties of concrete incorporating Rice husk Ash (RHA) and Concorb Ash (CCA) as cementitious binders. Concrete cubes was prepared from a standardized prescribed mix of 1:2:4. The cement component in the reference mix was replaced with combined % weight of rice husk ash and corncob ash. The physical and chemical composition of RHA and CCA were examined as well as the workability and compressive strength properties of varying percentage of RHA and CCA blended cement concrete. Water–cement ratios of 0.6, was adopted for the reference and blended mixes. A total of 75 concrete cubes of different percentages by weight of combination of RHA and CCA to Portland cement in the order of 0%, 10%, 20%, 30%, and 40% were cast. The strength measurements of concrete were performed at the ages of 7, 14, 21, 28 and 56 days. The results revealed that compressive strength increased with increase in curing age but decreased as the RHA and CCA contents increased. The compressive strength of concrete cubes with the combination of RHA and CCA was lower at early stages but improves significantly up to 56 days. The highest compressive strength was 22.94N/mm2 and 26.27N/mm2 at 56 days for 0% and 10% combination of RHA and CCA respectivelyBased on the test results the study concluded that 10% RHA and CCA content is adequate as supplementary cementitious material for blended concrete