Ayodeji Ogunde

Factors Militating Against Prompt Delivery of Construction Projects in Lagos Megacity, Nigeria: Contractors’ Perspective

Abstract Delay is a common issue faced in the construction industry all over the world especially in developing countries. The aim of this study is to evaluate factors causing delays and their effects on construction projects in Lagos Mega City, Nigeria from the contractors’ perspective. It is predicated on the incessant delay experienced by contractors on construction projects. Purposive sampling method was adopted for the study;. Quantitative data was obtained by administration of One hundred (100) structured questionnaires distributed to contractors of construction project sites in Lagos State and Qualitative data was obtained from interview of key management personnel of the companies and journals. Ranking analysis of the 33 major causes of delays identified through literature review using Relative Importance Index (RII) showed that cash flow problems during construction (RII=4.81), clients’ financial difficulties (RII=4.47) and poor procurement (RII=4.40) were the most importantt causes of delays in construction project sites in Lagos State, Cost overrun (RII=4.92), late payment (RII=4.59) and project extension (RII=4.45) were predominant effects of delay in construction project. Hypotheses testing on relationship between shortage of skilled labour, improper equipment during construction and delay in construction project using One-Way ANOVA showed positive correlation. For improved efficiency and effective project delivery in the industry, proper payment from client (RII=4.78), competent project managers (RII=4.64), the use of experienced subcontractors and suppliers (RII=4.48) should be encouraged to mitigate against delay in construction projects.

Data on factors influencing the cost, time performance of the Industrialized Building System

The data article provides the factors that influence the cost; time performance of the Industrialized Building System (IBS), its prospects and challenges. A survey technique was used for this research. Structured Questionnaires were administered to occupants of prefabricated buildings and interviews were conducted with the professionals in the building industry. Statistical Package for Social Sciences (SPSS version20) was used to analyse the data obtained from the questionnaires. The variables were ranked based on Relative Importance Index (RII) calculation. The Data indicated that IBS would be more economical if used for mass production.

Data on the pozzolanic activity in coconut shell ash (CSA) for use in sustainable construction

The data presented herein are results of the research summary of the investigation for pozzolanic activity in coconut shell ash (CSA) towards a sustainable construction. The data article provides information on the properties of Coconut Shell Ash that are indicative of pozzolanic activity as stated in ASTM C618-15 (2015) [1], BS EN 197-1 (2011) [2] and Joshua et al. (2018) [3]. The data are the physical property of the sand used in determining the binder strengths and the chemical and physical properties (oxide composition and Strength Activity Indices respectively) of the pulverized, calcined and sieved Coconut Shell Ash.

Data of the properties of rebar steel brands in Lagos, Nigerian market used in reinforced concrete applications

The data presented herein are compilations of the research summary of “Assessment of the Quality of Steel Reinforcement Bars Available in Nigerian Market” (Joshua et al., 2013) [1]. This data article provides information on the properties and cost of steel rebars used in reinforced concrete in Lagos, Nigeria. The data is based on the properties of 12 mm rebar brands which are the most used steel diameter in construction and they include actual diameters, yield strengths, ultimate strengths, ultimate/yield strength ratio, ductility and the cost of each brand. This data also contains the limiting standard properties of the highlighted properties in this data.

Pulverized Calcined Clay and Carbide Waste as Alternative Binder in Concrete and Mortar Applications for Sustainable Construction

Portland cement (PC) based concrete is the world’s most consumed man-made material and this consequently puts lots of demand on cement as a binder. The CO2 gas emission during cement clinker production has placed this important material into non-environmental-friendly classification with quest for greener alternatives being on the rise. A recent study showed combination of Pulverized Calcined Clay (PCC) and Calcium Carbide Waste (CCW) as possible alternative for total PC replacement with resulting appreciable mortar strength but delayed setting times and lower strength than PC mortars. This paper reports on effects of PCC-CCW as alternative binder on strength properties of mortars. The mortar mixes had superplasticizers added to reduce water/binder ratio while the CCW was treated to reduce impurities with a view to improving the strength development and a bid to mitigate the observed setbacks of earlier study. The pozzolanic activity indices of the PCC was determined via X-Ray Fluorescence(XRF) and strength determination (strength activity index). The PCC was combined with Purified CCW to determine the binder’s strengths at varying PCC:CCW replacements to determine the prescribed mix combination for optimum strength. Improved optimised mortar strength of 13.11MPa was achieved compared to 11.89MPa in the previous study