Faculty Publications
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Item Experimental studies on Iron-ore tailing based interlocking paver blocks(2012) Ravi Kumar, C.M.; Anil, A.; Prashanth, M.H.; Venkat Reddy, D.Interlocking concrete block pavers (ICBP) has been extensively used in many of the countries due to concern with durability. They are utilized in a variety of commercial, municipal and industrial applications. The superior engineering properties, low maintenance, ease of placement and removal, aesthetic appeal and immediate availability are the primary reasons for choosing concrete block pavement over other paving surfaces. ICBP are colored using iron oxide pigments. The present investigation details the properties of ICBPs mixed with iron ore tailings as a partial replacement for cement. The paper discusses the experimental studies on strength characteristics and water absorption of iron ore tailings based concrete paver blocks by considering actual area and plan area and results has been compared with that of conventional concrete paver blocks. © 2012 Cafet-innova technical society. © 2012 Cafet-Innova Technical Society.Item A study on the factors influencing the load transfer efficiency in concrete block pavements(2012) Thameel, S.S.; Amar Kumar, D.S.N.V.; Pancharathi, P.Concrete Block Pavements (CBP) are essentially precast blocks arranged in a specific pattern over a sub base and interlocked with graded bedding and jointing sand. The block size and shape, joint gap and joint filling sand size and laying pattern influence the effectiveness of the interlocking or the distribution of wheel loads. The measure of effectiveness - Load Transfer Efficiency (LTE), is the ratio of deflection between a loaded block to an adjacent unloaded block. In the present LTE study, joint filling sand of three particle sizes (1.18, 0.6 and 0.3mm), laying patterns of two types [stretcher and basket weave), concrete mixes with four variations (cement, cement with 20% fly ash, cement with steel fibre (0.5%) and cement with both fly ash and steel fibre] were tested. The test section consisted of 100 mm x 200 mm x 100mm blocks fixed over a 20 mm thick bed of 4.75 mm sand. A wet mix macadam layer over the sub grade supported the blocks. The study revealed that the joint filling with 0.6 mm sand gave a higher LTE than the other two sizes. The basket weave resulted in a higher average LTE than the stretcher bond and incorporating steel fibre and fly ash in concrete also showed an increase in the LTE.Item Implementation of model free fuzzy control on a novel magnetorheological elastomer-based handle for a rotary hammer(Institute of Physics, 2025) Kamath, N.; Shenoy, K.; Susheelkumar, G.N.; Gangadharan, K.V.This study presents a novel application of a Magnetorheological Elastomer-based handle (MREH) designed to improve the user’s comfort, specifically by reducing hand-arm vibrations. Various control logics were used on the MREH system attached to a rotary hammer to fully utilize the ability to adapt to various operating conditions, and each logic’s performance was evaluated. On/Off, PID, and fuzzy methods have been implemented in real-time. A case-based control logic where the frequency of the rotary hammer is given as an input to the control logic is developed to reduce the decision time as the events occur at a higher rate for on/off and fuzzy. PID gains are obtained directly from the experimental setup through PID autotuning. The performance of these logics is evaluated by performing a drilling operation on a M45 concrete block. Further, the fuzzy logic is investigated by operating at different locations on the same block. Based on the present research, fuzzy logic has demonstrated superior performance in aligning with the system by exhibiting a maximum 3 Hz increase from the natural frequency © 2025 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.Item Residual strength estimation of RC columns subjected to elevated temperatures from stress block parameters(Emerald Publishing, 2025) Akkannavar, C.S.; Prashanth, M.H.Purpose: In structural fire engineering, the design of columns is done either by prescriptive approaches or by empirical equations derived from experimental research. Performance-based design is the emerging methodology for designing structures under fire, which is case-specific. There is a need to develop design equations from first principles to design/find the residual strength of the column at elevated temperatures. The present study aims to develop equations from stress block parameters to find the residual strength of reinforced concrete (RC) columns subjected to elevated temperatures. Design/methodology/approach: The stress-strain variation across the cross-section of the RC column is determined at elevated temperatures. Based on the updated stress distribution diagram, stress block parameters are derived for various depths of neutral axis (NA) and different temperatures. Using updated stress block parameters, Pu-Mu interaction curves are generated for elevated temperatures. The results are verified against conventional methods and experimental results. Findings: The load-carrying capacity calculated from the proposed methodology is analogous to the experimental results. The methodology can be utilized to estimate the residual strength of RC columns subjected to elevated temperatures. Originality/value: The work done here attempts to develop the equations to estimate the residual strength of the column. The work involves calculating the strength of columns subjected to fire curves. © 2024, Emerald Publishing Limited.