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Understanding the dynamics of rock mass behavior necessitates the study of seismic waves generated by various sources of vibration within rocks. Joints and fractures are prevalent in rock masses and substantially impact their dynamic response to seismic waves. The present study has identified natural rubber latex (NRL) as an effective energy-absorbing medium in the rock masses for limiting wave propagation across the joint. Gypsum plaster has been used to replicate the natural rocks as a model material for conducting this study. The damping properties of rock mass have been determined using split shear plate (SSP) and resonant column (RC) tests. The mechanical response of intact gypsum plaster and NRL has been examined using resonant column testing. The influence of the thickness of the NRL layer on the damping characteristics of the jointed rock mass was studied by varying the thickness of the NRL layer within the joints from 2 to 5 mm. Using RC testing, the variations of shear moduli and damping ratios with different thicknesses of NRL have been studied. The variations of transmission coefficient (T), absorption coefficient (A), and reflection coefficient (R) with variable NRL thickness have been investigated utilizing SSP testing. The findings of the present study can be applied to developing numerical models that can anticipate the behavior of rock masses under dynamic loading conditions and for utilizing the NRL as an effective energy-absorbing material in the rock mass to reduce the vibrations that are transmitted to the structures. Practical Applications: The utilization of natural rubber latex (NRL) as an infill material in rock masses presents promising practical applications across various engineering domains. Its application extends to tunneling, mining, and stabilizing rock slopes. In tunneling and mining, NRL aids in increasing ground stability and controlling water intrusion during excavation, thereby enhancing safety and efficiency. In addition, it proves beneficial in stabilizing roofs and walls and preventing water and gas infiltration in mining operations. NRL reinforces joints within rock masses, reducing permeability and enhancing structural integrity. NRL stands out for its environmentally friendly and sustainable nature compared to synthetic polymers. Research indicates that NRL-stabilized soil has a lower carbon footprint than traditional cement-stabilized soil, thus offering an ecofriendly solution. Moreover, NRL presents opportunities for repurposing waste materials and reducing the environmental impact of concrete production. This study pioneers the application of NRL for vibration damping in jointed rocks, expanding the understanding of its dynamic properties under shear wave propagation. Through resonant column and split shear plate tests, this research explores the influence of NRL thickness on wave propagation, providing valuable insights for engineering practices in rock-dominated environments. [ABSTRACT FROM AUTHOR]

Assessing the dynamic properties of rocks remains a foundational pursuit in the field of rock engineering, providing crucial insights into their mechanical behaviors across a spectrum of loading conditions, including static, cyclic, and dynamic scenarios. This paper expounds upon the utilization of the nonresonance (NR) torsional shear test and its implications for understanding rock responses, particularly in the context of low and medium loading rates. The NR method serves as a pivotal tool for investigating model rock materials subjected to loading conditions characterized by low frequencies and amplitudes. Renowned for its efficacy, this method allows the simultaneous determination of two critical dynamic parameters: shear modulus (G) and damping ratio (D), all at a specific loading frequency. It has been ascertained that the loading rate increased as the loading frequency and applied amplitude of loading increased. With increasing loading rate, the shear modulus consequently increased while the damping ratio decreased. It is observed that the dynamic responses of both ramp and sinusoidal loading waveforms increase concurrently with the amplitudes of the applied torque and loading frequencies. The sinusoidal waveform exhibits greater dynamicity than the ramp waveform at a certain loading rate. Furthermore, this study delves into the intricate analysis of the nonlinear viscoelastic dynamic response exhibited by rocks, utilizing the modified hyperbolic (MH) model and the Ramberg–Osgood (RO) model as analytical tools. The findings derived from curve fitting exercises unequivocally underscore the superior applicability of the Ramberg–Osgood model, particularly in characterizing modulus reduction behavior. Conversely, the modified hyperbolic model emerges as the preferred choice for comprehensive damping ratio analyses. This study enhances the comprehension of rock dynamics and responses under diverse loading conditions, contributing valuable understanding to rock engineering. Insights into loading and strain rate effects aid informed decisions and preventive measures for rock deformation and collapse risks. Practical Applications: This research suggests vital findings regarding the response of intact model materials to various dynamic loading conditions, providing significant insights for comprehending the mechanical response of rock structures exposed to cyclic loading conditions, which have the potential to create weaknesses in rocks resulting in untimely failures. The research can be utilized to assess the response of rocks in the context of seismic incidents, specifically those characterized by shear waves at particular frequencies. This study evaluates the response of rocks during earthquakes by establishing a correlation between the amplitude of torsional shear loading and the peak ground displacement linked to seismic events. In addition to its seismic implications, this research aids in advancing accurate predictive models and instruments that assess the stability and integrity of rock formations under different loading rates—a consequence of the symbiosis between frequency and amplitude. Professionals may ensure efficient risk mitigation, make well-informed decisions, and execute preventative measures concerning rock collapse and deformation by virtue of their comprehensive awareness of the delicate relationship between loading rate and dynamic rock properties. Incorporating the findings into engineering design standards and codes can bring about substantial improvements, augmenting the overall reliability and protection of rock structures. [ABSTRACT FROM AUTHOR]

The study of site-specific dynamic properties of soil holds vital importance in many geotechnical engineering problems for the region holding high active seismicity. The Sutlej River basin, a valley and high-risk seismic zone in the north-eastern part of the Punjab state, has been considered for the study. The site-specific shear modulus reduction curves and material damping ratio curves for a range of shear strain amplitudes have been developed under varying experimental conditions of confining pressure, relative density, and loading frequency using the resonant column (RC) tests and cyclic torsional shear (CTS) tests. The study addresses the usage of two testing approaches, i.e., resonant column test (RC) and cyclic torsional shear test (CTS), for the estimation of shear modulus and damping ratio values at varying shear strain amplitudes. The regression analysis has been performed for the two testing techniques viz. RC and CTS to study the sensitivity of shear modulus values and material damping ratio values towards varying experimental conditions. The shear modulus and damping ratio values determined from cyclic torsional shear tests were observed to have great dependency on the frequency of loading. The knowledge of site-specific dynamic properties will support practical interpretation for the geotechnical engineering problems in the region. • The resonant column and cyclic torsional shear testing of Sutlej river sand have been performed under varying experimental conditions to analyze the dynamic properties. • Site-specific shear modulus reduction and damping ratio curves have been developed under varying relative density, confining pressure, and loading frequency conditions. • The influence of frequency of cyclic torsional shear loading on shear modulus and damping ratio has been analyzed. • The modified hyperbolic model has been used to assess the non-linear dynamic behaviour of sand. [ABSTRACT FROM AUTHOR]