Awareness, benefits and drawbacks of net zero energy building practices: construction industry professional’s perceptions

In a bid to overcome climate change and global warming, the adoption of net zero energy building (nZEB) practices in construction projects has become a viable measure of reducing energy consumption and CO2 emissions in buildings. nZEB is a facility with a significantly lowered energy needs such that the rest of the energy requirements can be supplied by on-site or off-site renewable technologies. The present study therefore investigated the awareness, benefits and challenges confronting the actualization of nZEB in Nigeria construction industry. A cross sectional survey design was adopted wherein a close ended questionnaire was purposively administered online to construction industry professionals who have understanding of nZEB initiatives. Descriptive statistical tests were conducted, with the results showing about 9% and 25% of the selected professionals been not aware of nZEB concepts and have not been involved in the concept in their professional career. Further details revealed that reduction in the land use effect, reduction in vulnerability of power infrastructures to vandalism and economic competitiveness were dominant benefits of nZEB practices. However, low return on investment, conflict with public policy regulation and policy clarity, lack of evaluation and valuation processes were perceived as the top hindering factors to nZEB practices. The implication for practice is for construction stakeholders to participate and develop effective implementation strategies towards nZEB for could be ecological and economical friendly

Human resource accounting and organizational productivity of listed manufacturing firms in Nigeria

In many developing economies, studies have shown that meeting organizational productivity seems complex and characterized with several factors affecting the productive inputs, due to infrastructural deficits and extent of employees’ motivations capable of impeding productivity. Beyond these, adequate human resource accounting has been identified as a possible solution. However, the extent to which human resource accounting could impact on organizational productivity remains uncertain. Consequently, this study investigated the effect of human resource accounting on organizational productivity of listed manufacturing companies in Nigeria. An ex-post facto research design was employed, while from a population of 66, the study selected 20 manufacturing companies listed in Nigeria as of 31 December 2021, using purposive sampling technique. Data were extracted from the financial statements of the selected companies for a period of 15 years spanning from 2007 to 2021. Using panel data analysis, the study found that human resource accounting had a positive significant effect on organizational productivity of the listed manufacturing companies in Nigeria. Based on the results, the study recommended that managers should consider appropriate incentives capable of improving employees’ productivity and adopt adequate human resource accounting models to enhance organizational productivity

World Cancer Day 2021: building a coalition for cancer control in a high-risk state in Nigeria

Objective: World Cancer Day (WCD) observed annually every 4th February has become a rallying point to create awareness and galvanise action globally to fight cancer. This paper describes the activities carried out in the oil-rich Bayelsa State of Nigeria to commemorate WCD 2021. Materials and Methods: Two non-governmental bodies collaborated to organise a series of campaign activities. These included health talks in clinics and on air, and a road walk that enjoyed the participation of other stakeholders in cancer control in the state. Results: Health talks and screening for the leading cancers were carried out in clinics and religious houses in all the eight districts of the state. Radio and television stations hosted talks on cancer prevention and control and over a hundred persons participated in the road walk. A large audience was reached with key messages of the day through the different media deployed for the campaign. Conclusions: WCD 2021 was able to sensitise residents of Bayelsa State to the growing burden of cancer and stimulated them to action. With sustained effort and commitment of all stakeholders, the state may soon have a well-established Cancer Control Programme and set the pace for other states in Nigeria

Mechanical properties of high strength eco-concrete containing crushed waste clay brick aggregates as replacement for sand

Utilization of clay brick wastes for production of high strength eco-concrete enables the combat of raw resources depletion due to excessive mining as well as mitigating environmental pollution caused by demolition of old brick structures in an effort to achieve environmental sustainability in line with the sustainable development goals (SDGs). This study investigates the beneficial usage of crushed clay brick as partial replacement for natural sand in producing high strength eco-friendly concrete. The replacement percentages of the crushed clay brick in respect to sand are 0, 10, 20, 30, 40 and 50% by weight using a mix proportion ratio of 1:1:2 at a constant water-cement ratio of 0.25, aiming at the 28 days compressive strength of about 40 MPa. The chemical characterization of the crushed clay brick and cement was conducted via X-ray fluorescence (XRF). The mechanical properties tests were performed on about 80 specimens using 100 x 100 x 100 mm for cubes, 100 x 100 x 500 mm for beams and 100 x 200 mm diameter for cylinders after 7, 14 and 28 days of curing in water. Results showed that concrete containing crushed clay brick as partial replacement for sand compare favourably well with the control. Consequently, it is suggested that generated clay brick wastes can be crushed and used as replacement for natural sand for the production of eco-friendly high strength concrete

FORECASTING THE HAZARDS OF SEISMIC INDUCED BUILDING COLLAPSE IN LAGOS NIGERIA THROUGH QUALITY OF REINFORCING STEEL BARS

Building structures are built to support specific class of loads and the design process starts with the choice of the most appropriate combination of materials for optimal safety, economy, aesthetics and social benefits. Reinforced concrete, comprising of concrete and steel reinforcing bars, is one of the most commonly used materials in the built environment industry worldwide. The expected quality of these materials used to produce reinforced concrete must be such that they guarantee ductile behaviour during the expected lifetime of the built structure. However, this is not usually the case in Nigeria, as cases of building collapse due to poor quality materials has been increasingly reported. Also, recent earth tremors in various parts of Nigeria has brought to the fore the need to consider seismic effects in future building designs in Nigeria, which until these recent events was considered aseismic. This research attempts to predict the risks of seismic-induced building collapse in Lagos-Nigeria from the quality of steel reinforcing bars commonly adopted in Lagos. Adopting a uniform seismic intensity similar to the one measured recently in Nigeria, Monte Carlo simulation method was used, employing MATLAB software, to draw random data of building area, occupancy limits, construction quality and failure probability for the study area. Results obtained show that as the quality of steel reinforcement decreases, the area to be affected by a moderate seismic occurrence increases together with the number of people at risk. The implication of this finding is that measures need to be taken to ensure that quality construction materials are used for construction in Lagos in order to protect lives and minimize damage to properties from possible future earth tremor or earthquake

The encumbrance of constructing on a swampy terrain

All through the ages, the provision of shelter has remained an ever-present challenge of mankind. Perennial difficulties of shelter provision are posed by varying strains dependent of numerous conflicting factors. Civil engineering and other specialty of science and humanity join hands in providing solutions to man’s basic housing and infrastructural needs, thereby adding values to what nature has provided. Constructing on different terrains cost different amount of resources and energy. This research evaluates the burden of constructing on swampy terrain. Mende-Maryland in Lagos is adopted as the area of study. This research analyzed the methods of constructing a duplex on a swampy terrain and modelled the behaviour of the same structure on a normal terrain. Successively, the economic burden of constructing on a swampy terrain is compared to that of constructing on a normal terrain. The result showed that constructing on a swampy terrain is a cost intensive process with the cost of pile foundation alone taking about 38 percent of the whole cost of construction when compared to the 17 percent cost of raft foundation for a normal terrain. This cost will go higher when the cost of engaging experts and equipment for soil consolidation, construction of superstructures on weak terrain and extra safety measures are computed

Response surfaces for properties of concrete with clay brick powder as substitute for cement

This study examined the application of pulverize clay brick wastes as alternative constituent for Portland cement replacement in green concrete production using the response surface methodology (RSM). The adopted response surface approach is central composite design (CCD). The statistical models were developed between the concrete constituents (clay brick powder and water cement ratio) and their response variables (slump, compressive and split tensile strength). Relationships were established and mathematical models in terms of actual factors from predicted responses were developed. The influence of the considered factors on the properties of response were visually observed from the contour and response surface plots. The statistical models of experimental values clearly depict that the obtained experimental values are in close agreement with the predicted values, which validates the response surface models with desirability value of 1. The results show that pulverized clay brick waste have significant influence on the properties of concrete than the water cement (w/c) ratio, however, a declining trend was seen for all analyzed concrete properties. In addition, this study showed that the pulverized waste brick can be used as alternative substitute for Portland cement up to 20% in the production of sustainable concrete

Perceived crime and traffic safety is related to physical activity among adults in Nigeria

Background: Neighborhood safety is inconsistently related to physical activity, but is seldom studied in developing countries. This study examined associations between perceived neighborhood safety and physical activity among Nigerian adults. Methods: In a cross-sectional study, accelerometer-based physical activity (MVPA), reported walking, perceived crime and traffic safety were measured in 219 Nigerian adults. Logistic regression analysis was conducted, and the odds ratio for meeting health guidelines for MVPA and walking was calculated in relation to four safety variables, after adjustment for potential confounders. Results: Sufficient MVPA was related to more perception of safety from traffic to walk (OR = 2.28, CI = 1.13-6.25) and more safety from crime at night (OR = 1.68, CI = 1.07-3.64), but with less perception of safety from crime during the day to walk (OR = 0.34, CI = 0.06- 0.91). More crime safety during the day and night were associated with more walking. Conclusions: Perceived safety from crime and traffic were associated with physical activity among Nigerian adults. These findings provide preliminary evidence on the need to provide safe traffic and crime environments that will make it easier and more likely for African adults to be physically active

Conformity of steel rebar used for reinforced concrete in Nigeria to the British Standards’ Benchmarks

Selection of construction materials are normally based on their ability to support design loads all through the service life of the structure to be built. For a reinforced concrete structure, the prime choices fall on the quality of concrete and steel reinforcing bars. Concrete is a composite of cement matrix which fills the space between aggregates and binds them together. Concrete quality fluctuates considerably for various reasons such as immense variability of constituent materials’ properties, the skill of the producer, placement procedure and environmental issues. Concrete is universally accepted for its excellent compressive strength. Concrete’s poor tensile strength is normally combined with the high tensile strength of steel reinforcing bar, providing a reinforced concrete composite that is universally accepted for construction. Steel is manufactured in specialized plants and the properties are controlled and certified by the manufacturer. The designer is, therefore, more confident in specifying steel quality complying with a relevant standard, while the choice of concrete mixes is not easy. Nevertheless, concrete and steel complement each other, compensating the weaknesses in the properties of the two materials, thereby making it a universal accepted construction material that has built the world’s most buildings and infrastructure. But due to the frequent cases of the collapse of reinforced concrete buildings and infrastructure in Nigeria, a study of the properties of steel samples available in Nigeria is essential. The scope of this research is on factors that influence the ductility of reinforced concrete, i.e., the properties of steel rebar. This study considers the yield strength and the chemical properties of the three most common diameters of steel rebar used in Nigeria. The results show some deviations in mechanical characteristics and chemical properties of some of the samples. This confirms that some of the samples fell short of the BS codes’ benchmarks for steel rebar