Geopolymer concrete is an alternative of ordinary Portland cement concrete made up of eco-friendly materials. This type of concrete assists in minimizing the greenhouse effects on the environment. Alkaline activator in geopolymer concrete plays an important role in the developing strength of concrete. This activator is made of sodium hydroxide and sodium silicate solution to different ratios with respect to molarity. The molarity of sodium hydroxide is crucial during the preparation of an alkaline activator. As the molarity of sodium hydroxide increase, the amount of sodium hydroxide increase which affect SS/ SH ratio. Fly ash plays a key role as the main source material in geopolymer concrete. GGBS is partially replaced with flyash to identify strength development of concrete. From the available studies, it is clear that the use of GGBS in fly ash always increases in strength of geopolymer concrete. However, the amount of GGBS should be restricted to the use of a huge extent to avoid the early setting of concrete. Moreover, it is understood that alkaline activators play a major role to develop bond between binders and aggregates. In this paper, few studies on the effect of alkaline activator with sodium hydroxide and sodium silicate under different curing with different molarities are discussed

Million tons of solid waste is being produced every year from various domestic and industrial activities in the Sultanate of Oman. Consequently, solid waste management has become one of the major challenges and environmental concern. Moreover, recent advancements and industrialization promoted the generation of various wastes such as municipal solid waste, e-wastes, industry waste etc. Scientific and sustainable recycling of industry byproducts as ingredients of concrete may protect environment and reduces the cost of construction. Cement Kiln Dust (CKD) is one of the byproducts of cement manufacturing process. In this study, an attempt was made to study the effect of CKD and Dune Sand (DS) on mechanical properties of M25 (1:1:2) grade of concrete. Experimental investigation was carried out to determine density, workability and compressive strength when Ordinary Portland Cement (OPC) is partially replaced with CKD varying from 0% to 50% with interval of 10%. In addition to this, Fine Aggregate (FA) was replaced with 20% of DS as constant. A standard water-cement ratio of 0.55 is maintained among all concrete mixes and tested at the age of 7 and 28 days. From the experimental results, it was noticed that replacement of CKD with OPC up to 30% and 20% of dune sand with fine aggregate has attained reasonable target strength of OPC concrete

Concrete is the most versatile and robust construction material available and has obtained a dominating position in construction. Today many reinforced concrete (RC) structures deteriorate owing to corrosion of reinforcement, just after a few years of completion reducing their service life. So it is essential to have the causes of deterioration highlighted, aiming at rectifying errors in design methods, construction procedures, material compositions as well as systematic planning of maintenance and repair procedures, to ensure more reliable structures in the future. Corrosion of steel reinforcement is because to two reasons; carbonation of concrete and/or chloride ingress in concrete. Carbonation reduces the concrete quality, results in additional shrinkage in the carbonated region, reduces the concrete`s ability to protect reinforcement from corrosion and develops in poor to medium quality concrete exposed to normal conditions within several months to several years of construction depending on conditions. The paper details a parametric study of service life assessment of RC structures based on service life model EXPERIMENTAL-REFERENCE for different exposure conditions based on European standard EN1992-1-1 "Eurocode2 (2004)”

Energy is the most important component of human life. Growing demand of energy due to rapid urbanization has focussed designer, building professionals and researchers to design energy efficient buildings and building envelopes. Energy efficient buildings encompasses various issues regarding energy, water, land and material conservation, together with environmental pollution and the quality of indoor and outdoor environment. Significant energy savings could be achieved through well designed building envelopes. This article strives to make an exhaustive review of the building envelope components and respective improvement from an energy efficiency perspective

Fluoride content in ground water is now a global problem, which affects more than 21states of India. Most of Ground water in the West Bengal and Eastern states are contaminated with Fluoride. Clean water use being a prime concern in many communities of developing country. Fortunately, efficient and cheap water purification systems are being utilized and tried to be accessed worldwide for easy access to clean water. The present work is deals with the usage of low-cost material such as rice husk ash, quartz sand etc., for removal of fluoride from water with various combinations which is benefit to human society for purification of water

Self compacting concrete (SCC) plays a significant role in construction industry as it reduces labor cost, results in faster construction and provides smooth finishing surface. In the present study, by combining the properties of self compacting concrete and fiber reinforced concrete that delivers high performance in many fronts. Fresh and hardened properties of self compacting concrete were determined through various experiments. Compressive strength and flexural strength are evaluated for the specimen casted with varying percentage of sisal fiber (0%, 0.25%, 0.5%, and 0.75%) and combination of % sisal fiber and 0.25% steel fiber after 7 days and 28 days of curing for M35 mix design. The study gives an insight into the influence of incorporation of sisal fibers and combination of sisal and steel fibers on the fresh and hardened properties of concrete

Delay is one of the principal measures of performance used to determine the level of service (LOS) at signalized intersections and several methods have been widely used to estimate vehicular delay. Very few studies only have been carried out to estimate delay at signalized intersections under mixed traffic conditions prevailing in developing countries like India. In the present study various problems associated with delay estimation under mixed traffic conditions in a developing country (India) and the methods to overcome them were discussed and an attempt was made to improve the accuracy estimating the same.

Uncontrolled intersections are vital points on urban roads, the performance of which will influence the traffic flow on entire network. Delays to vehicles at urban uncontrolled intersections depend upon the several factors, the most important among these being major road approach volume, type of turning movement, and vehicular composition. The average delay caused to vehicles is an important measure to evaluate the performance of uncontrolled intersections. The performance of an uncontrolled intersection is described by the service delay experienced by low priority movements. Under mixed traffic conditions, the traffic compositions, apart from the conflicting traffic volume and proportion of turning traffic are vital factors influencing the service delay. Most of the earlier studies conducted on this subject, pertain to homogeneous traffic environment, and only a few studies with limited scope have been conducted under mixed traffic conditions. In this study, the service delay has been analyzed for the intersection located in Narsapur, Telangana. The level of service for the uncontrolled intersections taken under the study has been evaluated using the estimated average service delays.

Self-compacting concrete is being widely used across the globe because of its sublime fresh and hardened properties. With speedy industrialization and growth in construction activities, the demand for natural river sand increased drastically leading to its enormous depletion. Furthermore, the disposal of industrial waste into the land causes environmental imbalance. Based on these reasons, the approach for sustainable construction is on the rise. Hence, in order to protect the environment and promote sustainable eco-friendly development, researchers have conducted experimental investigation on the suitability of alternative fines as replacement of river sand. This paper puts forward a thorough review of the physical and chemical characteristics of industrial by-products, followed by their effect on the fresh and hardened properties of SCC. Studies reveal that there is an encouraging future for the use of alternative fines in SCC. The key objective of this paper is to assess the work done by past researchers on the incorporation of alternative fines in SCC, provide sizeable information and the portion of work that needs to be done for future research

Controlling seismic damage and improving performance are creative ideas of earthquake designing in which uses definite demonstrating of the structure together with techniques. One of the most important tools to dissipate energy is dampers that are able to reduce vibrations. Especially Fluid Viscous dampers (FVD) which are used to investigate the response of Reinforced Concrete building when they are subjected to lateral load like seismic. A structure might be viewed as serviceable in the event where it can be satisfied by transferring loads to foundation. Since earthquake loads are imposed on a structure, vibrations occur. To resist responses and absorb energy, Fluid Viscous Dampers is used. With Equivalent Static, Response Spectrum and Time history method, it is vital to identify characteristics by (ETABS) finite element program where Models having ordinary RC moment- resisting frame by square column cross- sections with and without FVD. In this evaluation, it is utilized in linear and non- linear analysis where ETABS, Version (18.0.2), has been used. The results are shown that dampers (FVD) dramatically reduce the lateral deflection and enhance the performance of the structure. They also cause a decrease in Time period of maximum Psuedo Spectral Acceleration (PSA) in Response spectrum curves, increasing the story stiffness and decreasing the story Shear. Therefore, adding FVD to RC buildings is effective utilization due to its dissipation of energy.

This study shows at  that in view of the high flexural strength, high values of compressive strength  and high values of split tensile strength, higher load carrying capacity and higher life expectancy, the combination of 10 to 20% marble dust replacement along with addition of 0.5 to 1% steel fibers  is ideal for design  of Pavement Quality Concrete (PQC). This study also shows developing pavement quality concrete mixtures incorporating marble dust as partial replacement of cement as well as steel fibers.

Air pollution is one of the major issues in the current scenario of the technologically advanced world environment due the effects on the environment. Air is polluted due to various industrial, transportation and production activities. The contaminated air with harmful gases becomes serious risk to all the living creature and plants on earth. It has become essential activity to monitor and control of the air pollution in the industrial and metropolitan areas. Many conventional monitoring approaches are being used for the evaluation and controlling of air quality. But there is need of efficient and real-time systems air quality monitoring models which collect information about the concentration of air pollutants and also give assessment of the air pollution of the monitored area. This paper reviews the study of air pollution factors, air pollutants and various air monitoring methods. It also includes the brief study of the advance technologies like Internet of Things’ (IoT) with various sensors and Machine Learning (ML) based Artificial Intelligence (AI) model for the air quality data collection and analysis of the data for prediction and control of the air pollution.

About 6 million tonnes of plastic waste is generated in India and the toxic truth about these wastes that they are non biodegradable. India is the second largest populated country so as the use of resources is par to maximum and so as the generation of waste respectively. To adapt the sustainability between the resources available and the reusable waste, consuming plastic waste for recycling and reusing is fruitful for future generation. The organic polymer, plastic with high mass of molecules includes the substances like polyethylene terephthalate (PET) and polyvinyl chloride (PVC) while polystyrene and polymethyl methacrylate is much used plastic compound. As per the studies, plastic is added to bitumin in two ways that is dry process and wet process, in both these processes dry process is preferred because it is less expensive compared to wet process and also wet process requires large areas which is not easily approachable. While approaching to plastic, waste of plastic is shredded first and heated up to melting point then mixed with bitumin to make the composite material which is known as plastic modified bitumin (PMB). Performing the laboratory experiments it is studied that 5-7.5% PET can be mixed with bitumin for road construction and adding plastic in bitumin helps in improving the rheological properties of bitumin and with this replacement it helps in less consumption of bitumin which in turn saves the resources and also best way of disposing the plastic waste. This review presents the plastic waste is used to adapt sustainability to maintain economic approach and to recycle and reuse the plastic waste as the best deed of disposal. It also seeks the attention of the environmentalist and the scientist to work upon the emission of toxic gases in the environment which endangers lives causing diseases to living beings after the plastic roads are laid.

Many countries shut themselves off from the work due to the novel corona virus disease pandemic (COVID-19) that hit the world severely in the first quarter of 2020. The nationwide lockdown in India was imposed on March, 25, 2020, to curb spread of COVID– 19. Since the industries and people's activities have been shut off for a month or more in many parts of the world, it is expected to show  some improvement in the prevailing conditions in the aforementioned spheres of environment. Here, a comparative assessment of pollution levels during pre-lockdown and lockdown periods was made through analysis of data generated from 36 Real Time Water Quality Motoring Systems. It showed overall improvement in water quality of River Ganga especially with regard to increased Dissolved Oxygen (DO) and reduced nitrate concentration. This may primarily be attributed to absence of industrial wastewater discharge, agricultural runoff and increased fresh water flow. The reduction in Biochemical  Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) concentration was relatively less due to continued discharge of domestic wastewater into the river, with estimated quantity of 3500 MLD (Million Litres per Day) of sewage, out of which 1100 MLD is treated. Industrial effluent is estimated to be about 300 MLD, which is about 9% of total wastewater being discharged into the river every day. Reduced activities at Ghats and entrainment of solid organic waste into the river may also have contributed to better water quality.

In the current world scenario, the sites used for excavating natural aggregates are continuously getting depleted due to mining. Sustainable development is one of the main concerns for developing countries, especially in the field of building construction. While the mining sites of the aggregates are getting depleted, their prices of the aggregates are steadily increasing. Wastes generated from demolished structures are creating lots of pressure on land-filling. Recycling of the aggregates, which are generated from the demolished structures become the perfect solution for sustainable development. However, unlike natural aggregates, the structure of recycled aggregates is highly fractured. This affects the strength and durability properties of concrete made with recycled aggregates. Carbonation is one of the major durability concerns. The carbonation does not depend only on the recycled aggregate content. Concrete is a mixture of cement, water, aggregates, and additives. They all have a complex relationship with the mix proportion of the concrete. The main objective of this paper is to model the complex relationship of the mix proportion of the recycled aggregate concrete and the carbonation of the concrete. The data available for the durability properties of recycled aggregate concrete is often very limited. Thus, there is a need for multi-nation data analytics and problems like uniformity in the techniques of testing and results have to be sorted out. Linear models that are developed from the least square regression analysis are often ineffective in modeling the complex relationship of the carbonation of natural and recycled concrete. Machine learning algorithms are very effective in modeling such complex relationships with regards to the durability of recycled aggregate concrete. This paper aims to evaluate the effectiveness of the model generated from the linear regression and the artificial neural network and to evaluate the model in terms of accuracy and consistency.

The present paper focuses the experimental work done in accessing the durability of geopolymer concrete compared to conventional concrete in sulphate media. The molarity used for the preparation of geopolymer specimens is 12. The grade chosen for the investigation was M-30. The alkaline solution used for present study is the combination of sodium silicate and sodium hydroxide solution with the ratio of 2.50. The test specimens were 150x150x150 mm cubes, cured in ambient room temperature. The performance evaluation of the specimens were assessed by immersing geopolymer concretes (GPC1, GPC2) and OPC specimens in 5% magnesium sulphate solution separately, periodically monitoring surface deterioration and depth of dealkalization, changes in weight and strength over a period of 15, 30, 45, 60 and 90 days. The test results indicate that the geopolymer concrete has an excellent resistance to sulphate attack when compared to conventional concrete. Thus we can say that the production of geopolymers have a relative higher strength, excellent volume stability and better durability.