Science and Technology Magazine

For scientist and engineers

Nirmal Raj Joshi

  • Safety of deteriorated structures

    Safety of deteriorated structures

    By

    Nirmal Raj Joshi
    in ,

    The collapse of various civil engineering structures-such as bridges, dams, and buildings-has become a common occurrence in recent years, often attributed to aging and material degradation (refer to relevant news reports). Many of these structures were constructed decades ago, with assumed service lives typically ranging from 50 to 80 years. For instance, the design life…

  • Use of genetic algorithm for optimum proportioning of concrete

    Use of genetic algorithm for optimum proportioning of concrete

    By

    Nirmal Raj Joshi
    in , ,

    Genetic Algorithms (GAs) have emerged as a robust optimization technique within civil engineering, particularly in the design of concrete mix proportions. Their inherent ability to address complex, multi-objective, and nonlinear optimization problems makes them well-suited for this application. Conventional mix design methodologies often rely on iterative, trial-and-error approaches that are both time-consuming and may fail…

  • Implementing AI in civil engineering

    Implementing AI in civil engineering

    By

    Nirmal Raj Joshi
    in , ,

    Artificial intelligence (AI) is rapidly transforming civil engineering by offering innovative solutions that enhance efficiency, safety, and sustainability across a variety of applications. From optimizing structural designs to predicting maintenance needs and improving construction management, AI technologies are reshaping traditional practices. By analysing vast datasets, AI enables engineers to make informed decisions, leading to smarter…

  • Fatigue stress and RC deterioration

    Fatigue stress and RC deterioration

    By

    Nirmal Raj Joshi
    in ,

    Fatigue stress represents a critical factor in the progressive deterioration of reinforced concrete (RC) structures, particularly under conditions involving repeated loading and corrosive environments. The synergistic interaction between fatigue and corrosion, commonly referred to as corrosion-fatigue, significantly intensifies the degradation of structural materials, thereby diminishing overall structural integrity and long-term durability. Fatigue stress originates from…

  • Radius of earth (classical trigonometry)

    Radius of earth (classical trigonometry)

    By

    Nirmal Raj Joshi
    in ,

    Suppose that, while lying on a beach near the equator watching the sun set over a calm ocean, you start a stopwatch just as the top of the sun disappears. You then stand, elevating your eyes by a height H=1.7m, and stop the watch when the top of the sun again disappears. If the elapsed…

  • Techniques to make transparent wood

    Techniques to make transparent wood

    By

    Nirmal Raj Joshi
    in , , ,

    Transparent wood represents a major breakthrough in materials science, blending the inherent qualities of wood with improved optical transparency. This is accomplished by removing lignin-the component responsible for light scattering-through specialized processing techniques. Glycerol infiltration One effective technique for producing transparent wood involves the infiltration of glycerol into wood specimens. In a notable study, poplar…

  • History hydroelectricity in the Philippines

    History hydroelectricity in the Philippines

    By

    Nirmal Raj Joshi
    in

    The Philippines, an archipelago blessed with abundant water resources, has relied on hydroelectricity as a major source of renewable energy for over a century. From its early beginnings during the American colonial period to its current role in the nation’s sustainable energy strategy, hydroelectric power has significantly shaped the country’s economic and industrial development. However,…

  • Early days of FEA

    Early days of FEA

    By

    Nirmal Raj Joshi
    in

    During the 1940s, the world was embroiled in World War II, and the demands for more advanced and efficient aircraft surged. Aircraft engineering faced challenges due to the increasing complexity of designs, as manufacturers aimed to build planes that were lighter, faster, and more durable. This pressure led to the development and early application of…

  • Cavitation effect in concrete

    Cavitation effect in concrete

    By

    Nirmal Raj Joshi
    in

    Cavitation is a physical process that leads to surface pitting caused by the collapse of vapour bubbles, which results in a sudden rise in local pressure. In this article, we explore how this phenomenon can damage concrete. Damages by cavitation Cavitation can damage the concrete in the following ways: Shock Waves Generated by Bubble Implosion:…

  • Science of engineering tapes

    Science of engineering tapes

    By

    Nirmal Raj Joshi
    in , ,

    When one thinks about tapes, one might imagine a simple roll of something sticky. But dive into the aisles of a hardware store, and you’ll find a world of tapes with unique powers—some strong enough to fix a broken car bumper, others designed to hold up in the rain, and some even with colours and…