The construction industry (CI) has a significant impact on the environment and on climate change due to the emission of greenhouse gases like carbon dioxide. Globally accepted Sustainable Development Goals (SDG), specifically SDG 7 (Access to Affordable, Reliable, Sustainable and Modern Energy for All), SDG 9 (Industry, Innovation and Infrastructure), and SDG 11 (Sustainable Cities and Communities) stress the responsible utilization of energy in various industries, including construction. The CI uses almost half of the world’s produced energy. Therefore, this research presents insights into the efficient use of energy in the building sector and shows how energy efficiency can be achieved by altering different parameters and components like orientation, materials, glazing, and HVAC systems through a case study of a hospital building in Green Building Studio (GBS). This paper also aims to use the Building Information Modelling (BIM) approach to make environmentally sustainable decisions to reduce energy waste in projects. Initially, beneficial factors of BIM on green buildings were identified in the literature and later ranked, based on expert opinions collected using a set of questionnaires. Average Index was used for data analysis. The identified benefits were validated by conducting energy analyses on a hospital model through 3D BIM. It was concluded that a substantial share of energy cost, carbon dioxide (CO2), and electricity can be saved using this approach. It was determined that a quick and sustainable design process, improved energy efficiency, enhanced building performance, and provision of better design alternatives are the key benefits of the adoption of BIM by such projects. A Cronbach’s alpha value of 0.822 was obtained, which further validates the results. The proposed approach may lead future structures to be sustainable and enriches the culture of energy-efficient green buildings.

Concrete is highly utilized construction material around the globe and responsible for high depreciation of the raw materials. Consumption of this material in construction industry is arching upward day by day. On the other hand, debris of demolished concrete structures are being dumped as waste. For developing countries such waste is not a good sign and need its proper utilization by recycling it into useful product. In this consequence, this study is an attempt to utilize demolished waste concrete by converting into coarse aggregates. This research was conducted on recycled cement concrete aggregates of demolished structures and Rice Husk Ash (RHA). The purpose of this experimental study is to analyze the mechanical properties of concrete; when cement is partially replaced with RHA and natural aggregates by recycled aggregates (RA). In this study, the cement was replaced by RHA up to 10% by weight of cement. For experimental purpose, total 135 concrete specimens were prepared, cured and tested in Universal Testing Machine (UTM). Finally, laboratory results were compared in terms of compressive and splitting tensile strength made with normal and recycled coarse aggregates. All the specimens were prepared at 1:1.5:3 with 0.50 w/c ratio and tested at 7, 14, 21, 28 and 56 days curing ages. It is observed from experimental analysis that the workability of fresh normal concrete is 7% and 10% greater than recycled aggregates concrete blended with 10% RHA and only recycled aggregates concrete without RHA respectively. The compressive strength increases up to 6%, whilst splitting tensile strength increases 4% at 56 days curing, when the cement is replaced 10% by RHA. It is, further, concluded that with more than 10% RHA replacement with cement, the compressive strength decreases. This study would help the construction experts to use such wasted concrete into useable production of new concrete projects.

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In construction project management, the contractor plays a primary role. Selection of the contractor is a matter of concern for clients as this is a key player who ensures better performance of a project. This paper structurally investigates the literature from credible databases and renowned journals from 2000 to 2018 in matters related to contractor selection. This investigation sets to accomplish three objectives. Firstly, it includes the identification of criteria and sub-criteria and their organization into a proper classification. Secondly, it highlights the types of decision-making techniques applied in articles published on contractor selection. The third objective covers a detailed investigation of current saturation and gaps of this area of study around the globe. The findings of the research are critically discussed in the light of the literature. As very limited work has been carried out in the area of contractor selection, this paper fills this gap in knowledge in the context of a structured review.

The purpose of this study is to explore Vygotsky's contribution to the socio-cultural theory in the field of education in general, and applied linguistics in particular. The study aims to elaborate the impact of social-cultural theory in the existing body of literature. The study also reviews implications and applications of socio-cultural theory in second language acquisition (SLA). Moreover, this study also critiques the basic concepts of the theory and how far these concepts have been implicated in the domain of research. The central focus is to explore and to critically understand central ideas such as Zone of Proximal Development, mediation, scaffolding, internalization, and private speech. The socio-cultural theory focuses on what learners learn and the solution to their learning problems. Socio-cultural theory has made a great effect on learning and teaching languages. It also regards learning second language as a semiotic process where participation in socially mediated activities is very important (Ellis, 2000). Vygotsky (1987) singled out and studied the dynamic social surroundings which indicate the connection between teacher and the child. Moreover, he focused on the social, cultural and historical artifacts which play a pivotal role in the children's cognitive development as well as their potential performance. The study concludes with the idea of Williams & Burden (1997) that socio-cultural theory suggests that education should be associated with learning to learn and making learning experiences meaningful and relevant to the learner. The study also suggests some pedagogical implications and offers teaching and learning practices in relation to socio-cultural theory.