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In this paper, the mechanical and durability properties of aerated blocks are discussed. Aerated blocks are prepared using different cementitious materials with an alkaline solution in the absence of aluminium powder. The proportions of raw materials are chosen after performing two mix trials P1 and P2, keeping the density of the blocks constant at 800 kg/m3. Each mix is further tested under six curing mechanisms, namely, normal water curing, humidity chamber curing (at 50°C and 70% relative humidity) for 6 h and 10 h, curing by oven drying at 180°C for 6 h and at 80°C for 24 h and using an accelerated curing tank (ACT) at 65°C ± 5°C for 10 ± 2 h; this is termed trial 1. In trial 2, the best curing mechanism is taken and construction and demolition wastes (CDW) are substituted at different proportions in place of fly ash in both the mix proportions. In addition, trial 3 investigates the best mix proportions by substituting glass powder at 50% and 100% with fly ash and CDW, respectively. It is observed from experiments that aerated blocks manufactured with 50% CDW and heat curing by ACT showed high mechanical and durability properties after 7 days of hardening. [ABSTRACT FROM AUTHOR]

The global concern about water quality in coal mining operations is a significant issue. It presents detrimental water-related threats, including pollution, acid mine drainage, and habitat destruction. In this study, an attempt has been made to evaluate the water quality for domestic, irrigation and industrial purposes in the coal mining province of Mahan catchment area, with a particular focus on the impact of coal mining activities. 50 samples from pre-monsoon season of 2018, collected from dug well, tube well, mine water and river water were analyzed. The findings indicate that water in the study area exhibits acidic characteristics, with pH values below the desirable range for drinking water. Elevated electrical conductivity, total dissolved solids, sulphate, total hardness and chloride concentrations are observed, particularly around core mining regions. For irrigation suitability, the study reveals that most of the samples are suitable, based on parameters such as sodium percentage (Na%) sodium adsorption ratio (SAR), magnesium hazard (MH), Kelly's index (KI), permeability index (PI), and residual sodium carbonate (RSC). However, majority of the samples collected from core mines show an elevated range of Na% (>80), SAR (>60), MH (>50), KI (>1), PI (>100), RSC (>2.5) and PS (>5) indicating potential soil permeability issues and crop damage, which restrict its suitability for agricultural use. Furthermore, the assessment of water for industrial suitability by analyzing the scaling and corrosion indices, such as the Langelier index (LI), aggressive index (AI), Ryznar index (RI), Puckorius index (PI), and corrosivity ratio (CR) highlights the presence of a corrosive tendency in majority of the water samples, particularly in the mining areas. [ABSTRACT FROM AUTHOR]

The Eastern Indian Gangetic Plains are characterized by a primarily nature-dependent region blessed with an enormous supply of mineral resources. The region is witnessing a rapid transition in its demographic structure because of rapid industrialization. The region provides a classic example of an area which shows a trend reverse to that observed globally, as far as the frequency of extreme precipitation events is concerned. This paper provides a risk characterization of the entire region, based on the empirical behavior shown by data available so far, in addition to predictions based on theory of extreme values. The long-term behavior prediction is made with an aim to provide policy makers ample time and direction to develop suitable disaster prevention measures. The focus is primarily on extremely high rainfall events, their frequency, trend and estimated long-term behavior. The study corroborates the stability assumption behind the Indian monsoon, and also provides an indication of the expected long-term as well as short-term threats. This study provides a unique application of the extreme value theory to help in developing a threat map for a region whose population is known to be highly impacted by any significant deviations from a normal monsoon. [ABSTRACT FROM AUTHOR]

Hydrologic simulations of different models have direct impact on the accuracy of discharge prediction because of the diverse model structure. This study is an attempt to comprehend the uncertainty in discharge prediction of two models in the Ghatshila catchment, Subarnarekha Basin in India. A lumped Probability Distribution Model (PDM) and semi-distributed Soil and Water Assessment Tool (SWAT) were applied to simulate the discharge from 24 years of records (1982–2005), using gridded ground based meteorological variables. The results indicate a marginal outperformance of SWAT model with 0.69 Nash-Sutcliffe (NSE) for predicting discharge as compared to PDM with 0.62 NSE value. Extreme high flows are clearly depicted in the flow duration curve of SWAT model simulations. PDM model performed well in capturing low flows. However, with respect to input datasets and model complexity, SWAT requires both static and dynamic inputs for the parameterization of the model. This work is the comprehensive evaluation of discharge prediction in an Indian scenario using the selected models; ground based gridded rainfall and meteorological dataset. Uncertainty in the model prediction is established by means of Generalized Likelihood Uncertainty Estimation (GLUE) technique in both of the models. [ABSTRACT FROM AUTHOR]