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Due to immense infrastructure development activities, a study on the vibration generated by heavy machinery, construction activities, highway and railway traffic movements has gained importance in recent years. The present study investigates the influence of shape on the system and vibration transmission characteristics of block machine foundations under dynamic loading. A series of block vibration tests were conducted on model foundations laid on the local soil available at IIT Kanpur, India, to evaluate the system characteristics of machine foundations. The vibration transmission characteristics of the foundations were investigated using a 3D finite element (FE) analysis. Three different shapes of foundation (circular, square, and rectangular) were considered for the intended purpose. The effect of the loading intensity on various parameters such as natural frequency, soil stiffness, and damping coefficient was investigated. In addition, the shape effect of foundations on the dynamic shear strain, shear modulus, and the elastic uniform compression coefficient was suitably assessed. The efficiency of a wave barrier in mitigating the machine-induced vibration was investigated. It can be observed that the shape of foundations significantly influences the system characteristics. The circular and square foundations perform better than the rectangular foundation at higher loads. In contrast, the vibration transmission characteristics of block foundations are unaffected by the shape of the foundations. The transmission ratio decreases with an increase in the frequency at the pick-up points located away from the vibration source. It can be noted that the absolute damping varies significantly in the presence of the wave barrier at higher frequencies.

Utilisation of fly/pond ash has been a great concern across the world over the last two and half decades. Therefore, a need arose to evolve an effective and sustainable procedure to utilise such hazardous waste material. This work explores the judicious addition of fibre and kaolinite in pond ash-based geopolymers. The shear strength parameters, peak deviatoric stress, stress–strain relationships and microstructure of such geopolymers were investigated and reported. In this study, the geopolymer paste was cast in a mould and an unconsolidated undrained triaxial test was performed on the sample. Pond ash- and pond ash–kaolinite-based geopolymers are found to exhibit excellent strength. It is observed that the strength of geopolymers increases with increase in the level of kaolinite. It is additionally observed that an addition of fibres enhances the ductility and strength of simple pond ash-based geopolymers, whereas with an increase in the kaolinite level, the impact of fibres on the strength of pond ash–kaolinite-based geopolymers becomes negligible.

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