Faculty Publications

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Author: search.filters.author.Srinivasan, V.

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    Data Aggregation of Tweets and Topic Modelling Based on the Twitter Dataset
    (Association for Computing Machinery, 2021) Srinivasan, V.; Chandrasekaran, K.
    Twitter is one of the most popular online social networks. It has a relatively simple data model and an intuitive API to access Twitter data. This makes it easy to collect social data and analyse the patterns of online behaviour. Twitter has an impactful presence among politicians, entrepreneurs, news agencies, public figures, and this makes it a crucial playground for social discussion. The topics discussed on Twitter often lead to or are the cause of social events. Therefore, a lot of information can be inferred from Twitter data. This can be used by NGOs, government agencies or policymakers to develop meaningful understanding and respond to the emerging trends. In this project, I will discuss a method to aggregate tweets related to Elon Musk and Tesla from Twitter servers using the Twitter API in the form of a web crawler. The data obtained from the web crawler will be combined with a ready-made dataset containing similar information, and the datasets will be merged together. After collecting relevant tweet information, I will perform topic modelling using Latent Dirichlet Allocation (LDA) on his tweets to find out the most common topics tweeted by Elon Musk. © 2021 ACM.
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    Effect of High Temperature on the Compressional Wave Velocity of Two Sandstones with Different Grain Sizes
    (Springer Science and Business Media Deutschland GmbH, 2024) Manikanta, V.; Hasainar, H.; Badiger, N.K.; Kothari, V.; Bhat, A.; Srinivasan, V.
    Understanding rock behaviour at high temperatures can serve as vital information in restoring fire-damaged monumental structures. This knowledge is essential for engineering and construction purposes, as it allows for assessing rock stability and potential hazards and developing appropriate safety measures in areas with high temperatures. This study investigates the effect of different temperatures on two sandstones with varying grain sizes. The rock was first heated to a range of temperatures such as 35, 250, 500, 750, and 1000 °C. To identify the thermal damage of the rock samples, the Ultrasonic Pulse Velocity measurement instrument is used to identify the inner cracks. This research discusses the application of Ultrasonic Pulse velocity (UPV) to identify thermal damage and analyse related parameters of two different sandstones. The ultrasonic method is one of the simple and reliable techniques to understand the damage conditions of rocks. There were significant variations in the P-wave velocity with thermal treatment, it is observed that a negative trend developed in the primary wave velocity as the temperature increased. They give qualitative and quantitative inferences on the extent of damage caused by various environmental parameters, particularly heating. The data obtained from the present study were compared to check the confidence of regression models. The mean absolute percentage error method, the root mean square error method (RMSE), was carried out on thermal damage of rock samples. Probabilistic analysis was also conducted to estimate the damage on rocks at different confidence levels. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.
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    Effect of Heating and Fluid Saturation on Certain Physico-Mechanical and Fracturing Behaviour of Concrete
    (Springer Science and Business Media Deutschland GmbH, 2024) Gafur, I.A.; Anilkumar, A.; Parappalli, A.N.; Srinivasan, V.
    Understanding the fracturing characteristics of construction materials under varying environmental conditions is very important in considering the safety of infrastructural facilities for sustainable civil structures. Concrete has been extensively used in construction, and with recent advancements in offshore structures, its strength in adverse conditions is pivotal and hence requires significant attention. This study investigates the variation in the mechanical properties and fracturing behaviour of M25 concrete cubes under different environmental conditions. The cubes were subjected to five different conditions: heating, saturation, and a combination of heating and saturation. Saturation was carried out separately using water and brine solutions. Three cubes were cast for each condition. The physical properties included density and Ultrasonic pulse velocity, followed by mechanical testing for strength. Acoustic emission monitoring was carried out simultaneously along the mechanical testing. Acoustic emission techniques are used to visualize fracturing behaviour of concrete cubes. Fracture thresholds are established to find crack closure and elastic region, and regions of stable crack propagation and unstable crack propagation. The results show that the combination of heating and fluid saturation significantly impacts the physico-mechanical properties of concrete, reducing its compressive strength and increasing its susceptibility to fracture. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.
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    The Physical and Mechanical Properties of Closepet Granite After Thermal Treatments with Water and Brine Cooling Conditions
    (Springer Science and Business Media Deutschland GmbH, 2025) Raj, M.S.V.; Srinivasan, V.
    In recent years, efforts to utilize geothermal systems as a clean and renewable energy resource have gained considerable significance. This is due to unprecedented carbon emissions from the conventional fossil fuel system, which resulted in increased carbon footprints. Granite rocks, often prioritized for geothermal extraction, are relatively intact. Hence, such reservoirs require induced fracturing for the development of an enhanced geothermal system. Several studies have been carried out to clarify the fundamental behavior of rocks encountered in the geothermal energy systems and to assess their effectiveness during energy production. In this study, granite rocks belonging to the Closepet granitoid of Eastern Dharwar Craton were investigated for their physical and mechanical stability under different fluid conditions after heating to elevated temperature levels. This study experimentally investigates the influence of heating and cooling by different fluids on the physical and mechanical properties of Closepet granite. The granite specimens prepared as per international standards were heated at specific temperatures of 100℃, 200℃, 300℃, 400℃, and 500 °C. The heated samples were quenched in two different fluids, like brine and water. The influence of different cooling fluids on the physical properties like P-wave, bulk density, and the mechanical properties such as Uniaxial compressive strength (UCS), Brazilian tensile strength (BTS), Elastic modulus (E), and was determined experimentally. The damage introduced by the thermal treatment was evaluated from the arrived physical and mechanical parameters. The experimental results suggested that the physical and mechanical properties under brine quenching are more severe than those under the water cooling program. This study provides an insight into the enhanced effect of fracturing fluid on the behavior of rocks under geothermal energy production. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.
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    An Investigation on the Influence of Thermal Damage on the Physical, Mechanical and Acoustic Behavior of Indian Gondwana Shale
    (Springer, 2020) Srinivasan, V.; Tripathy, A.; Gupta, T.; Singh, T.N.
    In the present study, the effect of thermal treatment on the physical, mechanical and fracturing behavior of Gondwana shale samples from India was investigated. Acoustic Emission signals were used to identify the changes brought in by temperature variations on the crack damage zones and failure attributes in shale. The results suggested that mechanical parameters such as uniaxial compressive strength, tensile strength (?t), elastic modulus, mode-I fracture toughness (KIC), cohesion, and brittleness index (B1) exhibited a strong negative correlation with thermal damage (Dt). But, the internal angle of friction and brittleness index (B2) showed a reasonable positive relation with thermal treatment. The deformation of the shale was dominated by its clay mineral enrichment, the characteristics of which changed with heating. The intensity of fracturing as observed from acoustic signals was chiefly controlled by the orientation of bedding planes and the degree of thermal treatment. The initiation and propagation of macro-crack were found to be greatly influenced by the degree of thermal damage. Under compression, thermally damaged samples showed similar deformation pattern, while under Brazilian tensile load, the deformation path became inconsistent with increasing temperatures. It was observed that thermal damage in tested shale decreased the layer compaction, which eased the fracturing intensity, thereby reducing the overall strength of the samples. The present investigation concludes that even a slight change of the thermal conditions can substantially alter shale fracturing behavior and failure attributes posing serious safety concerns of deep geo-engineering structures. © 2020, Springer-Verlag GmbH Austria, part of Springer Nature.
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    An experimental study on rock damage and its influence in rock stress memory in a metamorphic rock
    (Springer, 2020) Srinivasan, V.; Gupta, T.; Ansari, T.A.; Singh, T.N.
    Rock stress memory, often referred as Kaiser effect, in rocks can be an effective tool to estimate the in situ stress conditions, if the uncertainties in rock damage and its behavior during loading conditions are properly understood. In view of this, the present study is an attempt to investigate the variations in rock stress memory, i.e., the Kaiser effect in a metamorphic rock under multi-stage uniaxial compression. The khondalite rock samples from Eastern Ghats Mobile Belt (EGMB) belonging to southeastern part of Indian subcontinent having complex geological history are examined. The effects of multi-stage compression on the damage evolution and subsequent variations in rock stress memory are investigated. The samples were categorized into different levels of rock stress memory, depending on the stress the rock was able to withhold after loading stages. The damage evolution in the tested rocks was predominantly controlled either by initial loading or failure stress. Higher damage imparted by initial loading and intense fracturing could be the possible reason for poor stress memory function in the investigated rock. Felicity ratio, an indicative of rock damage with stages of loading, supported the observation that rock damage was dominant during initial loading stage. Rock heterogeneity has played a dominant role in decay of Kaiser effect, with intense fracturing during subsequent loading stages in the investigated rocks. To summarize, Kaiser effect can be used to infer rock damage and stress conditions, provided the geological history of the region is also taken into consideration. With rocks from complex geological conditions, Kaiser effect or rock stress memory should be supported by other tools to infer in situ stress, but the method can be effectively used to understand the stress changes and damage mechanism of multiple loading. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
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    Experimental study on failure and fracturing attributes of granite after thermal treatments with different cooling conditions
    (Elsevier B.V., 2022) Srinivasan, V.; Hasainar, H.; Singh, T.N.
    Thermal damage is one of the fundamental mechanisms affecting the stability of rocks encountered in many deep geo-engineering ventures such as nuclear waste isolation, geothermal extraction etc. In the present study, the findings on influence of heating and subsequent cooling conditions on the fracturing and mechanical behaviour of an Indian granite are discussed. The granite samples from Jalore region of India were heated from room temperature to 600 °C followed by slow cooling and water quenching treatments. It was observed that rapid cooling through quenching had a greater impact on strength, elastic properties than slow cooling rate. Moreover, a drastic shift in terms of fracturing thresholds was witnessed, as a function of both temperature and sudden thermal shock experienced by rock at higher cooling rate. The simultaneous AE monitoring results suggested an early crack damage at higher thermal regimes. With help of microscopic observations, it was observed that inter-granular crack boundaries widened with increasing thermal damage experienced by minerals under both cooling conditions. However, the fracturing process was intense under rapid cooling treatment due to the invasion of water due to quenching which accelerated severe intra-crack growths, especially at higher thermal stress because of the rapid cooling rate than the slow cooling. The increased intensity of thermal cracks with temperatures and with variation in cooling rate was inferred as the primary reason for decay of rock characteristics. This was very well supplemented by decay in strength properties and changes in fracturing attributes of the tested granite as inferred from acoustic monitoring. © 2022