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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]

Expansive soils present substantial challenges in civil engineering because they undergo volume fluctuations with changes in water content, mainly affected by the clay mineral montmorillonite. Nanotechnology has rapidly and widely improved, finding applications across all engineering fields. This study focused on enhancing soil engineering performance using lime alone and the impact of varying quantities of nanosilica with lime in the soil, focusing on engineering parameters like Atterberg limits, maximum dry density, optimum moisture content, and unconfined compressive strength over curing periods of 7, 14, and 28 days. In this study, the basic properties of soil were initially determined. Then, lime was mixed with soil in different proportions of 2%, 4%, 6%, and 8% according to the dry weight of the soil. Based on strength criteria, soil mixed with 4% lime gives the best results. Keeping the lime content constant at 4%, nanosilica was added to the soil. These findings suggest modifications in the amended soil's plasticity, compaction characteristics, and strength with the minor addition of nanosilica to lime-mixed black cotton soil. The enhancement in strength of expansive soils relies on the amount of lime and nanosilica and the duration of curing. After conducting tests, it was found that the optimal quantities for lime and nanosilica through strength performance tests are 4% and 3%, respectively. The research asserts that adding nanosilica to lime notably improves the mechanical properties of black cotton soil. Scanning electron microscopy and X-ray diffractometer analyses support these findings, revealing variations in the character and strength of the CSH phase over curing time. These conclusions offer wide-ranging relevance for projects seeking to enhance the engineering properties of soft soils. Practical Applications: Soil with 4% lime and 3% nanosilica gives good results, and the use of lime in soil stabilization contributes to the reduction of environmental pollution. The cost of nanosilica for real projects demands huge quantities. From an economic and commercial perspective, nanosilica liquid and lime are generally considered cost-effective for most practical applications. However, nanosilica with lime is recommended in areas where durability is important. Lime with soil is used to strengthen the soil in pavements and embankments; for example, when strengthening black cotton soil used for an embankment with a top width of 2 m, height of 6 m, side slope of 1:1, and length of 1 m, the volume is calculated as 48 m³. For soil +4% lime +3% nanosilica, the dry density is 17.1 kN/m³ and the moisture content is 14.9%. Considering this, the mass of the sample is obtained as 943 kN. Consequently, the required quantities are 38 kN (3,872 kg) lime, 28 kN (2,435 L) nanosilica liquid, and 877 kN (89,443 kg) of soil in its dry state. The cost of lime and nanosilica liquid depends on the location. [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 presence of discontinuities in the rock mass is extremely crucial in many engineering applications of rock mechanics. The estimation of the joint roughness coefficient (JRC) utilising easily accessible camera-friendly devices and application software has recently gained prominence. The joint roughness coefficient of a jointed rough surface may be calculated using either contact methods (physically contacting the surface to get the profile) or non-contact methods (extraction of the profile without physically touching the surface using laser profilometry or 3D laser scanning and photogrammetry techniques). The 3D laser scanner is widely used for its accuracy in obtaining the surface topography of rock masses; however, the practice is often uneconomical due to the high equipment cost. In this study, the smartphone photogrammetry technology is used to extract the three-dimensional surface topography of a jointed rough surface in order to evaluate the JRC. For the comparative study, the surface profile was retrieved using a surface profilometer, 3D scanner and photogrammetry method. The JRC values for the surface profiles gathered through smartphone photogrammetry, 3D scanning and surface profilometer have been estimated using visual analysis, fractal dimension and statistical techniques. The study found that the surface profile generated using the photogrammetric approach utilising smartphone delivers more realistic profiling than the surface profilometer because of the lower least count and greater precision. The predicted JRC values for smartphone photogrammetry profiles agreed well with the JRC values obtained for 3D scanner and surface profilometer profiles. [ABSTRACT FROM AUTHOR]