This paper presents an experimental study on the strength and durability properties of Geopolymer concrete prepared using Ground Granulated Blast Furnace Slag (GGBS) and Black Rice Husk Ash (BRHA). The Geopolymer concrete was prepared with GGBS as the primary binder instead of cement and BRHA was replaced with GGBS at various proportions such as 10%, 20% and 30%. The effect of curing temperature on the compressive strength of Geopolymer concrete was studied in addition to the flexural and split tensile strengths. Studies on the durability performance under Sorptivity, Rapid Chloride Permeability Test and Accelerated corrosion were also made. The test results show that the strength of Geopolymer concrete increases with increase in curing temperature. Addition of BRHA in Geopolymer concrete beyond 10% retards the strength development yet the strengths are well above the target for up to 20% replacement levels. At the same time, addition of BRHA significantly improves the durability with reduced sorptivity and chloride permeability when compared to the control concrete. Higher corrosion initiation and delayed cracking time were observed up to 20% BRHA replacement in Geopolymer concrete.

Purpose: Lean construction is a technique that aims at reducing waste in construction and maximizing productivity. The purpose of this paper is to discuss the effectiveness of Lean technique in managing construction projects.Design/methodology/approach: A case study of structural steel erection project was chosen where the value stream mapping lean tool is applied and the possible improvement in productivity was observed. The current state of the activities in the erection process was mapped first which was followed by preparing the Future State Map of the activities after eliminating the non-value adding tasks.Findings: The modifications from Future State Map were carried out at the project and the results exhibited a substantial increase in productivity by reducing the project duration by 13 days which is about 30 per cent savings from the expected completion time after the implementation of Lean technique.Originality/value: Traditionally lean concept has been widely used in process-oriented manufacturing industry whereas it is relatively new to the project-oriented construction industry. This current research has focused on applying lean tool to a real time construction project at the site level and measuring its outcome practically. The results of this study are real and affirm the effectiveness of applying lean concept to construction projects. It will be major paradigm shift in terms of managing construction projects.

In recent years Asian Nations showed concern over the Life Cycle Assessment (LCA) of their civil infrastructure. This study presents a contextual investigation of a residential apartment complex in the territory of the southern part of India. The LCA is performed through Building Information Modelling (BIM) software embedded with Environmental Product Declarations (EPDs) of materials utilized in construction, transportation of materials and operational energy use throughout the building lifecycle. The results of the study illustrate that cement is the material that most contributes to carbon emissions among the other materials looked at in this study. The operational stage contributed the highest amount of carbon emissions. This study emphasizes variation in the LCA results based on the selection of a combination of definite software-database combinations and manual-database computations used. For this, three LCA databases were adopted (GaBi database and ecoinvent databases through One Click LCA software), and the ICE database was used for manual calculations. The ICE database showed realistic value comparing the GaBi and ecoinvent databases. The findings of this study are valuable for the policymakers and practitioners to accomplish optimization of Greenhouse Gas (GHG) emissions over the building life cycle.

Geopolymer concrete with ground granulated blast furnace slag and black rice husk ash An experimental study on the strength and durability properties of geopolymer concrete prepared using the ground granulated blast furnace slag and black rice husk ash is presented in the paper. The geopolymer concrete was initially prepared with ground granulated blast furnace slag as the primary binder instead of cement, and then blast furnace slag was replaced with black rice husk ash. The addition of more than 10 % of black rice husk ash in geopolymer concrete retards the strength development, although such strength values are still above the target strength for up to 20 % replacement levels.

Construction industry across the world has been facing immense challenges in improving its productivity and efficiency. In the path of continuous improvement, the companies are forced to impart new technologies and methods into their work culture. But still there is a fine line between what they have achieved and what they wanted to achieve. Lean Construction is an ideology designed to fill this fine line. The aim of this paper is to discuss the application of Lean techniques in construction management. A case study where the Lean concept is applied using Value Stream Mapping tool to reduce the cost of the design process of foundation for Gas Insulated Switchgear by improving the process productivity has been discussed. The current state of the activities in the design process was mapped first which was followed by preparing the future state map of the activities after eliminating the non-value adding tasks. The results exhibited a promising increase in productivity of about 30% after the application of Lean tool.

The potential contribution of district assemblies to improving health and safety in Ghana's construction industry has not been investigated. This paper attempts to identify the local government responsibilities that could influence health and safety performance in the construction industry and to develop a confirmatory factor model based on these responsibilities. The paper adopted a positivist philosophy and a deductive methodology. A literature search was conducted to identify the local government factors that could potentially impact health and safety performance in the Ghanaian construction industry. These factors were adapted and designed into a questionnaire, and the generated questionnaires were distributed to respondents for their feedback. It was identified using the relative importance index that “the development of sanctions for violating occupational health and safety statutory obligations,” “the institution of local government occupational health and safety approval and certification for new projects,” and “the creation of occupational health and safety departments and committees that are adequately resourced to assist the Department of Factories Inspectorate” were the three most important roles that district assemblies could play as partners to improve health and safety in the construction industry. Conversely, the multivariate analysis identified the evaluation of the safety policies and risk management plans of contractors and suppliers as the most important role local government institutions could play in improving health and safety in the construction industry. The result of the study suggests that local government efforts, when given the needed attention and support, could advance health and safety in the industry. The practical implication of the study is that it identifies the roles of district assemblies that could enhance health and safety in Ghana's construction industry. All district assemblies should consider implementing these health and safety initiatives in their districts and ensuring they are regularly enforced and evaluated.