Regulation of a water resource system is one of the challenging tasks due to uncertainty involved in demand and supply. It may be due to changes in the climatic conditions, living standards of people, land-use patterns and even because of changes in technology. The problem becomes even more complicated if the objectives pertaining to demand and supply are multiple and conflicting in nature. Therefore, this paper deals with regulation of water resources system based on "if-then" fuzzy logic-based rules which interlinks concepts of interpolative reasoning, logical implications and certain inference tools to infer knowledge about a water resource system using linguistic descriptions. Reasonable inferences have been drawn using concept of tautologies viz. modulus ponens and modulus tollens. Finally, the model is applied to a practical case study in order to demonstrate effectiveness of the proposed logic. The main motive of this study is to demonstrate applicability of fuzzy inference system for regulating operations of water resource systems.

Extensive studies have been reported on the development of service-life prediction of reinforced concrete structures in the last two decades. Service life of a reinforced concrete structure is dependent on the corrosion process, specifically chloride threshold value. Chloride threshold value is a distinctive property and is dependent on several factors such as the supplementary cementitious material used, presence of surface cracks, water to binder ratio, type of steel reinforcement, exposure conditions, measurement methods, etc. Although chloride threshold value is an influential parameter in service-life prediction, a definitive chloride threshold value considering these factors is not reported in the existing literature and standards. Moreover, values adopted in many analytical tools for service life predictions based on the type of steel reinforcement alone are not appropriate and leads to inaccurate calculations. There is a gap in the available literature in understanding the selection of suitable chloride threshold values to be adopted for a specific system. Therefore, it is imperative to study the variation of chloride threshold value with exposure conditions as well as other influencing parameters, to achieve proper service life prediction. In the paper, several influencing parameters on chloride threshold value and its significance on prediction method are comprehensively reviewed. Moreover, suitable recommendations are highlighted for Indian and international standards at the later part of the study.

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The construction of high rise buildings and tunnels has necessitated concrete pumping to long distances. Concrete pumping is a complex physico-chemical process that results in the formation of different layers with distinct characteristics inside the pipe. A thin cement paste/mortar layer formed at the concrete-pipe interface, called the lubrication layer (LL) is considered vital for facilitating concrete pumping. Engineering the pumping process involves understanding the origin, controlling the onset, magnitude and velocity of the LL. However, the formation, evolution, and characteristics of LL are still largely unexplored. This paper presents comprehensive review of the mechanistic origins of LL, its influencing parameters, and the measured data on LL thickness using various techniques till date. It is attempted to find the overall link between the different theories such as shear induced particle migration (SIPM), wall depletion theory etc. in terms of concrete rheology. Further, the paper also provides a fundamental understanding of the different mechanisms involved in the formation of LL, with the help of different theories put forth by researchers in the field of particle rheology. Based on the insights derived from the discussions, recommendations have been made for future research directions in concrete pumping.