bluuebunny/crossref_metadata_2025 huggingface dataset:
High-speed multi-parameter sensing system based on wireless passive SAW tags
Authors: Feng Yan , Zhang Yue , Gao Feng , Zhang Jikai , Ding Qingchen , Dong Shurong , Jin Hao , Xuan Weipeng , Luo Jikui
Published: June 2024

Wireless passive surface acoustic wave (WP-SAW) tags are widely used for onsite real-time monitoring of mechanical moving parts. However, the high running speed of some core parts results in fast variation of the sensing parameters such as stress or strain, which requires high sampling rate. This is challenging for WP-SAW because of its traditional frequency interrogation scheme by frequency sweeping, especially under high temperature. This paper proposed a high-speed sensing system based on WP-SAW tags for the real-time interrogation of multiple parameters including temperature, pressure and strain. The high-speed reading is achieved by interrogation with linear frequency modulated continuous waves, which can achieve a fast single cycle sampling time of 36.25 μs. The sensor tag is built by direct integration of a SAW resonator with a PCB spiral antenna. Langasite is chosen as the SAW substrate to achieve high working temperature. The temperature, pressure and strain sensing ranges of the wired SAW resonators are room temperature to 1000 °C, 0.1 MPa to 0.8 MPa and 0 μϵ to 1000 μϵ, respectively. The design of this wireless passive sensing system demonstrates a feasible monitoring solution that can be widely used in high-speed and high-temperature moving mechanical parts.
Validation of MAPS: a novel 6-degree-of-freedom position sensor for nanopositioning
Authors: Aras Richard , Dallas James , Heaps Edward , Varga László , Yacoot Andrew
Published: June 2024

Anemos’ multi-dimensional absolute position sensors (MAPS) consists of a photolithographically defined reference scale, a camera, and computer image processing that decodes the relative position of a camera to the scale. A series of experiments tested the novel opto-electronic sensor against traceable National Physical Laboratory optical interferometers (OI) with motion provided by nanopositioning stages. Initially, MAPS to OI agreement was verified to be within 5 nm in the lateral (XY) axes across 100 μm travel. However, when MAPS, OI, and stage position were correlated across much finer steps, MAPS demonstrated repeatability and noise below 100 pm, indicating that the larger discrepancies seen previously were due to Abbe effects, servo-mechanical, and other OI/MAPS-extrinsic factors. In a third experiment, the outputs of four orthogonally placed MAPS 6-degree-of-freedom (6DoF) sensors were correlated against each other, OI, and feedback from a single-axis stage. Here, MAPS displayed sub-nanometre agreement with other sensors, and consistency across independent MAPS sensors. A fourth experiment collected millions of MAPS sample points during repetitive 1 nm circular motion. Spectral analysis of these large datasets, correlations between noise in multiple axes and repeatability indicate MAPS may resolve single digit picometre movements. These results corroborate simulations and supports the feasibly of million-to-one position interpolation from the MAPS 5 μm-grid reference scale. This equates to an unprecedented 40-bit dynamic range since MAPS can sustain measurement resolution over metres of travel. Overall, the experimental series highlight the challenges of nanoscale calibration and benefit of full 6DoF sensing in real-world nano-positioning systems.
Joint moments of higher order derivatives of CUE characteristic polynomials II: structures, recursive relations, and applications
Authors: Keating Jonathan P , Wei Fei
Published: June 2024

In a companion paper (Keating and Wei 2023 Int. Math. Res. Not.
2024 9607–32), we established asymptotic formulae for the joint moments of higher order derivatives of the characteristic polynomials of CUE random matrices. The leading order coefficients of these asymptotic formulae are expressed as partition sums of derivatives of determinants of Hankel matrices involving I-Bessel functions, with column indices shifted by Young diagrams. In this paper, we continue the study of these joint moments and establish more properties for their leading order coefficients, including structure theorems and recursive relations. We also build a connection to a solution of the σ-Painlevé III

′

equation. In the process, we give recursive formulae for the Taylor coefficients of the Hankel determinants formed from I-Bessel functions that appear at zero and find some differential equations these determinants satisfy. The approach we establish is applicable to determinants of general Hankel matrices whose columns are shifted by Young diagrams.
Transport characteristic evaluation of runaway electrons in an ITER disruption simulation
Authors: Liu Shi-Jie , Wang Feng , Hu Di , Wang Zheng-Xiong ,   the JOREK team
Published: June 2024

In previous studies, it has been observed that the transport of energetic electrons decreases with increasing energy. This observation is a global and long-time-scale result, attributed to the space-averaged perturbations. In this work, we focus on the local and instantaneous transport characteristics of runaway electrons (REs) during the phase of tokamak disruption, with REs speeds close to the speed of light. To simulate the dynamics of REs, we utilize a particle tracing code called PTC. By coupling PTC with the MHD code JOREK, we are able to study the energy and spatial dependence of RE transport. Our investigations reveal that the finite orbit width (FOW) effect plays an important role in RE transport. This effect is influenced by the relative direction of the electron drift and the magnetic field line. Specifically, the FOW effect strengthens the transport when the drift direction aligns with the deflecting direction of the field line. And we compare the transport profiles among three time slices: at the beginning of the thermal quench, during the thermal quench, and at the beginning of the current quench. In this ITER disruption simulation, the perturbation scale is strong and

δ
B

/

B

is up to 0.05 at developed thermal quench stage. It is reasonable that the influence of FOW effect on transport is less than that of magnetic perturbation even if the energy of REs is about hundreds MeV and the orbit width is equal to or greater than the perturbation length. These analyses provide insights into the mechanisms of RE transport based on magnetic perturbations.
Turbulence generation in the solar corona through nonlinear interaction between 3D kinetic Alfvén wave and magnetic islands
Authors: Patel Garima , Uma R , Sharma R P
Published: June 2024

This study investigates the interaction between kinetic Alfvén waves (KAWs) and magnetic islands in solar corona region. KAWs and magnetic islands are believed to be one of the key players in the heating of the coronal plasma and particle acceleration. We have used the dynamical model for KAWs to simulate its propagation through magnetic islands. The equation is solved numerically by using the finite difference and pseudospectral technique for spatial and temporal variations. The simulation results have been studied and signatures of turbulent structures evolving with time have been observed. Turbulence plays a considerable role in tapping out magnetic energy to thermal energy. The plot of the energy spectrum as a function of wavenumber exhibits a power law behavior in the inertial range, characterized with an exponent around

−
5

/

3

. Beyond this range, the spectrum becomes steeper. In order to gain a more thorough knowledge of the physical processes that underlie the development of localized structures and to estimate the current sheet scale sizes, a semi-analytically model is also performed. The results indicate that the size of localized structures are comparable to ion gyro-radius, and different intensities of KAW further modify this length scale formed at different times. The purpose of the study is to acquire an understanding of the KAW propagation in magnetic islands and the way it contributes to the formation of turbulence and energy release in the solar corona. A comparative aspect of the non-linear interaction of 3D KAW with magnetic island and null point is also presented which shows that non-linear interaction of 3D KAW with null point, leads to rapid disorganization of the magnetic field and the creation of localized structures.
Online meta-learning approach for sensor fault diagnosis using limited data
Authors: Wang Lei , Huang Dukang , Huang Ke , Civera Marco
Published: June 2024

The accurate and timely diagnosis of sensor faults plays a critical role in ensuring the reliability and performance of structural health monitoring (SHM) systems. However, the challenge is detecting, locating, and estimating sensor faults in an online manner using limited training data. To resolve this problem, a novel approach for online sensor fault diagnosis is proposed for SHM. The proposed approach is based on meta-learning, which enables superior model generalization capabilities using limited data. The detection, localization, and estimation of typical sensor faults in an online manner can be achieved efficiently by the proposed approach. First, a one-dimensional convolutional neural network (1D CNN) is designed to detect and locate faulty sensors. The initial model parameters of the 1D CNN are optimized using a model-agnostic meta-learning training strategy. This strategy allows the acquisition of transferable prior knowledge, which can speed up the learning process on new sensor fault detection and localization tasks. The meta-learning strategy also enables efficient and accurate detection and localization of potential faulty sensors with limited data. After detecting and locating the faulty sensors, an online updating algorithm based on a dual Kalman filter is used to estimate the severity of sensor faults and structural states simultaneously. The proposed approach is demonstrated with simulated sensor faults that cover a numerical example and field measurements from the Canton Tower. The results show that the proposed approach is applicable for online sensor fault diagnosis in SHM.
A piezoelectric pump with composite chamber: using bluff body to improve its anti-clogging ability
Authors: Chen Song , Fang Xuan , Xie Yilei , Huang Zijian , Zhan Weijun , Kan Junwu , Zhang Zhonghua , Li Jianping
Published: June 2024

Piezoelectric pumps are widely used in biomedicine, chip cooling, fuel cells and so on. However, existing valve-based piezoelectric pumps suffer from the problem of easy clogging. In order to solve the problem, a piezoelectric pump with composite chamber (PPCC) is proposed. The composite chamber, consisting of drive chamber and flow chamber, which provides the PPCC with excellent output performance by amplifying the compression ratio. Meanwhile, a bluff body is set in the drive chamber, and the vortex flow around the bluff body is able to adsorb air bubbles and other impurities, preventing impurities from entering the drive chamber, the bluff body provides the PPCC with strong anti-clogging ability. Multi-physics field simulation is established, which verifies the PPCC is feasible. The fluid inside the pump chamber is simulated, and it is concluded that the 90-arc bluff body is optimal, favoring the formation of high-speed vortices. Furthermore, a prototype is fabricated and experimentally investigated. The experimental results show that the PPCC has excellent performance in pumping liquid and gas. At 300Vpp, the PPCC delivered a maximum flow rate of 235.9 ml min−1 for air and 24.07 ml min−1 for water. The anti-clogging ability of PPCC is verified through bubble resistance experiments, which demonstrates the composite chamber and bluff body effectively prevent foreign impurities from entering the drive chamber. The PPCC provides a new approach to microfluidic pumping devices.
Collimated beam formation in 3D acoustic sonic crystals
Authors: Vanel A L , Dubois M , Tronche C , Fu S , Wang Y-T , Dupont G , Rakić A D , Bertling K , Abdeddaim R , Enoch S , Craster R V , Li G , Guenneau S , Perchoux J
Published: June 2024

We demonstrate strongly collimated beam formation, at audible frequencies, in a three-dimensional acoustic phononic crystal where the wavelength is commensurate with the crystal elements; the crystal is a seemingly simple rectangular cuboid constructed from closely-spaced spheres, and yet demonstrates rich wave phenomena acting as a canonical three-dimensional metamaterial. We employ theory, numerical simulation and experiments to design and interpret this collimated beam phenomenon and use a crystal consisting of a finite rectangular cuboid array of

4
×
10
×
10

polymer spheres 1.38 cm in diameter in air, arranged in a primitive cubic cell with the centre-to-centre spacing of the spheres, i.e. the pitch, as 1.5 cm. Collimation effects are observed in the time domain for chirps with central frequencies at 14.2 kHz and 18 kHz, and we deployed a laser feedback interferometer or Self-Mixing Interferometer – a recently proposed technique to observe complex acoustic fields—that enables experimental visualisation of the pressure field both within the crystal and outside of the crystal. Numerical exploration using a higher-order multi-scale finite element method designed for the rapid and detailed simulation of 3D wave physics further confirms these collimation effects and cross-validates with the experiments. Interpretation follows using High Frequency Homogenization and Bloch analysis whereby the different origin of the collimation at these two frequencies is revealed by markedly different isofrequency surfaces of the sonic crystal.
Monogamy of quantum correlations shared in a cavity-freeoptomechanical system
Authors: Hmouch Jamila , Amazioug Mohamed , Nassik Mostafa
Published: June 2024

In this work, we discuss the monogamy property of quantum correlations (entanglement and steering) distributed in a cavity-free optomechanical system. In a tripartite pure Gaussian state, we verify the hierarchy of the studied quantum correlations. We investigate in detail the CKW-type monogamy inequalities, based on Gaussian Rényi-2 entropy entanglement, as well as, Gaussian steering. We quantify genuine tripartite entanglement by using the minimum residual Gaussian entanglement. In addition, we consider the minimum residual Gaussian steering as a quantifier of genuine tripartite steering. Our results indicate that, in the one-mode versus two-mode Gaussian state, the correlations hierarchy was respected; in the considered pure state, the monogamy of entanglement and steering distribution was proven and the studied genuine tripartite correlations have similar time evolution under the same conditions.
Optical intensity figures of merit of insulator-metal-insulator and metal-insulator-metal thin-film stacks
Authors: Raşeev Georges
Published: June 2024

This paper discusses the quality factors Q and the intensity figures of merit (IFoM) evaluating the intensity and leakage of modes of the reflection flux and of the plane-wave and locally excited transmitted fluxes of insulator-metal-insulator (IMI) and metal-insulator-metal (MIM) 2D planar thin-film stacks, here air-Au-glass and air-Au-SiO2-Au-glass stacks respectively. These thin film stacks sustain a single surface plasmon polariton (SPP) and multiple planar waveguide (PWG) modes. The Q and IFoM of the 3D dispersion graph (in-plane wave vector k

ρ
/k
0 ∈ [0, 1.52]/frequency ω ∈ [0.5, 2.7] eV/observable dispersion) are calculated and analyzed along 2D cuts where either the in-plane wave vector k

ρ
/k
0 or the frequency ω are varied the other independent variable being kept fixed. Here these two cuts are called spatial (ω fixed) and frequency (k

ρ
/k
0 fixed) domains. Due to a lower leakage, the Q and IFoM of the IMI and MIM thin film stack modes are significantly larger in the spatial domain than in the frequency domain. In the spatial domain the IMI and MIM stack modes dominate at low and high frequencies respectively. In the frequency domain, the Q and IFoM of a MIM stack mode is always larger than that of an IMI stack. Our results span a large domain of frequencies in the SPP and RPP region and of the in-plane wave vector whereas the results in the literature presented above concern only particular laser frequencies and limited in-plane wave vector values. Our Q and IFoM of the 2D planar thin film stack modes, obtained with optimized independent variables, are larger than those of other planar thin film stacks but smaller than some 2D/3D nano scale samples with an involved geometry. The simplicity of producing these simple IMI and MIM stacks permit their use in the applications.
Design and development of a first order reversal curve measurement enabled variable temperature vibrating sample magnetometer
Authors: Pratheek  , Badiger Hanamanta , Sah Nutan Kumari , Joshi Rajeev S , Bhat Subray V , Hegde Balachandra G
Published: June 2024

In this paper we present the design, construction and calibration of a sensitive vibrating sample magnetometer (VSM) and temperature variable setup with a capability to measure magnetization of magnetic materials from 100 K to 400 K with First Order Reversal Curve (FORC) measurement facility. It uses a bipolar power supply to energize an electromagnet capable of attaining ±1 Tesla field, subwoofer speaker for vibrating the sample and the induced voltage in four coil setup is measured by a lock-in amplifier. All hardware is controlled by a customized LabView program. The cryostat is designed such that the temperature can be varied continuously from 100 K to 400 K using liquid nitrogen up to room temperature and forced nitrogen gas/air for high temperatures study. We report here the VSM sensitivity of up to 10−2 emu/gm and can measure much weaker signals. The FORC protocol in this system is implemented via a dedicated virtual instrument in LabView capable of magnetic field reversal and termination at appropriate point to study domain nucleation field. The detailed analysis of the data is done using the open-source resources. We present the FORC measurement for Co0.5Zn0.5Fe2O4, a ferrimagnet. To establish the sensitivity of the instrument we present the results of magnetization measurement with temperature and phase transition study of La0.4Ca0.6MnO3 and La0.75Sr0.25MnO3.
Extended rubber-elasticity model for non-Gaussian isotropic hyperelasticity of polyelectrolyte hydrogels undergoing curl-to-stretch transition
Authors: Shi Weilin , Lu Haibao , Fu Yong-Qing
Published: June 2024

The nature of extremely high stretchability in hydrogels with a non-Gaussian elasticity has been extensively investigated. However, there are few studies on curl-to-stretch transitions of condensed polymer networks in polyelectrolyte hydrogels and their non-Gaussian hyperelasticity. In this study, an extended rubber-elasticity model was developed to investigate different mechanical behaviors, e.g., S-shaped and J-shaped stress-elongation ratio curves, where the condensed polymer networks in polyelectrolyte hydrogels undergo a curl-to-stretch transition and present a non-Gaussian isotropic hyperelasticity. A free-energy equation was formulated to describe the curl-to-stretch transitions and their thermomechanical conformations of condensed polymer networks, based on the free energy functions of elasticity, electrostatics and hydrophobicity. A constitutive relationship between stress and elongation ratio was then proposed to describe the non-Gaussian isotropic hyperelasticity in polyelectrolyte hydrogels, and effects of segment number, charged segment fraction and salt concentration on the mechanical behaviors were studied. Moreover, a segmental length criterion of condensed polymer networks was proposed to distinguish the S-shaped and J-shaped stress-elongation ratio curves. Finally, experimental data reported in literature were applied to verify the effectiveness of the proposed theoretical models. This study aims to provide a new thermomechanical criterion for non-Gaussian isotropic hyperelasticity in polyelectrolyte hydrogels undergoing the curl-to-stretch transition.
Analytical and numerical calculation of the effect of edge states of the Kane-Mele model on the RKKY interaction
Authors: Alsayyid Y , Ahmadi J , Soltani M , Rashedi G
Published: June 2024

In this paper, we investigate the Kane-Mele model and endeavor to demonstrate, through analytical calculations, how the presence of topological edge states influences the RKKY interaction. We illustrate that the effect diminishes as one moves away from the edges. To facilitate our analytical approach, we initially utilize a one-dimensional wire exhibiting linear dispersion for each spin as an approximation to the Kane-Mele model. We examine its impact on the RKKY interaction. Subsequently, we establish a correspondence between the edge states of the Kane-Mele model and a one-dimensional quantum wire model, wherein the coupling strength diminishes with increasing distance from the edges. Finally, we compare the analytical results with numerical findings obtained using the Landauer-Buttiker formulation.
Influence of temperature-dependent density inhomogeneity on the stability of atmospheric stratified fluids
Authors: Kaladze T D , Misra A P
Published: June 2024

The stability of atmospheric stratified fluids is revisited to study the influence of the temperature-dependent density inhomogeneity due to thermal expansion in the Earth’s lower atmosphere (with heights 0 to 50 km) under the action of gravity. Previous theory in the literature [Phys. Lett. A 480 (2023) 128 990] is modified and advanced. It is found that the Brunt-Väisälä frequency associated with internal gravity waves is modified, leading to new instability conditions of vertically stratified fluids. The possibility of the onset of Rayleigh-Bénard convective instability is also discussed, and the influences of the modified Brunt-Väisälä frequency and the density and temperature gradients on the instability growth rates are studied.
Bose–Einstein distribution temperature features of quasiparticles around magnetopolaron in Gaussian quantum wells of alkali halogen ions
Authors: Zhang 张 Xin 鑫 , Sarengaowa 萨 仁高娃 , Han 韩 Shuang 爽 , An 安 Ran 然 , Zhang 张 Xin-Xue 新雪 , Ji 纪 Xin-Ying 新颖 , Jiang 江 Hong-Xu 红旭 , Ma 马 Xin-Jun 新军 , Li 李 Pei-Fang 培芳 , Sun 孙 Yong 勇
Published: June 2024

We have applied strong coupling unitary transformation method combined with Bose–Einstein statistical law to investigate magnetopolaron energy level temperature effects in halogen ion crystal quantum wells. The obtained results showed that under magnetic field effect, magnetopolaron quasiparticle was formed through the interaction of electrons and surrounding phonons. At the same time, magnetopolaron was influenced by phonon temperature statistical law and important energy level shifts down and binding energy increases. This revealed that lattice temperature and magnetic field could easily affect magnetopolaron and the above results could play key roles in exploring thermoelectric conversion and conductivity of crystal materials.
Towards electrophysiological measurement of presence in virtual reality through auditory oddball stimuli
Authors: Savalle Emile , Pillette Léa , Won Kyungho , Argelaguet Ferran , Lécuyer Anatole , J-M Macé Marc
Published: June 2024

Objective. Presence is an important aspect of user experience in virtual reality (VR). It corresponds to the illusion of being physically located in a virtual environment (VE). This feeling is usually measured through questionnaires that disrupt presence, are subjective and do not allow for real-time measurement. Electroencephalography (EEG), which measures brain activity, is increasingly used to monitor the state of users, especially while immersed in VR. Approach. In this paper, we present a way of evaluating presence, through the measure of the attention dedicated to the real environment via an EEG oddball paradigm. Using breaks in presence, this experimental protocol constitutes an ecological method for the study of presence, as different levels of presence are experienced in an identical VE. Main results. Through analysing the EEG data of 18 participants, a significant increase in the neurophysiological reaction to the oddball, i.e. the P300 amplitude, was found in low presence condition compared to high presence condition. This amplitude was significantly correlated with the self-reported measure of presence. Using Riemannian geometry to perform single-trial classification, we present a classification algorithm with 79% accuracy in detecting between two presence conditions. Significance. Taken together our results promote the use of EEG and oddball stimuli to monitor presence offline or in real-time without interrupting the user in the VE.
Numerical modelling of sawteeth and sawtooth-free regime
Authors: Yu Q. , Günter S. , Lackner K.
Published: June 2024

To better understand the sawteeth physics and the sawtooth-free regime associated with the hybrid scenario in tokamak experiments, numerical calculations up to quasi-steady state have been carried out for realistic middle-size tokamak plasma parameters, including the bootstrap current perturbation and basing on both the single- and two-fluid equations with the large aspect ratio approximation. Two types of the sawtooth crash are found in multiple sawteeth simulations: (1) For a low equilibrium bootstrap current fraction, the crash is caused by the internal kink mode, as expected; (2) When the bootstrap current density fraction is larger than 10% in the core region, however, the crash is caused by the non-ideal double kink mode, in contrary to the conventional understanding. In this case, a non-monotonic radial profile of the safety factor

q

with two

q
=
1

surfaces emerges before the crash, caused by the bootstrap current density and plasma resistivity perturbations, although the original equilibrium has only single q = 1 surface. In both types of sawtooth crashes, the crash time in two-fluid simulations is tens of microseconds, as observed in experiments. Furthermore, for a relatively low ion density and finite bootstrap current density fraction, a transition from the sawtooth to the sawtooth-free regime is found, in which flat

q

profiles with the

q

value being about unity in the central region, similar to that observed in hybrid scenario experiments, are maintained by the dynamo effect. To enter into the sawtooth-free regime in two-fluid simulations, a much larger Alfvén velocity than that in single-fluid simulations is required due to the diamagnetic drift.
Corrigendum: On the τ-p Transform and Seismic Data (2024 J. Phys.: Conf. Ser. 2701 012087)
Authors: Hjouj Fawaz
Published: June 2024

Please see Article PDF for corrigendum text.
Evaluation of Seismic Response on Small-Scale Reinforced Concrete Frame Using Small-Scale Low-Cost Equipment’s
Authors: Senthil K , Yadav Manav , Singh Talwinder , Sharma Rachit
Published: June 2024

The security of the infrastructures is an important part and the responsibility of the nation. Therefore, the study is focused on investigating the seismic response of small-scale buildings through the shake table test. The small scale reinforced concrete building of two storey was modelled through the experiment as well as numerical simulations considering 40 MPa concrete strength. The size of the slab was 600 × 600 mm and thickness were 40 mm. The cross section of the column was 50 × 50 mm whereas the height was 300 mm. The galvanized wire was used as main reinforcement and stirrups bar having tensile strength 875 MPa and yield strength 636 MPa. The small-scale building frame was tested under the small-scale shake table which is working with adjustable speed by varying the voltage. The seismic waves were varied by considering different voltages such as 20, 40, 60 and 80V using the shake table. In order to minimize the percentage of error, more than 20 sets of observations were made at each of the voltage levels. The frequency of seismic waves such as 0.175, 0.348, 0.511 and 0.692/s was produced corresponding 20, 40, 60 and 80V, respectively. The displacement of slabs on the ground floor, first, second and third floor was recorded using the LVDT for the duration of 50 sec. The maximum top storey displacement was 50.45, 51.70, 55.31 and 61.04 against the frequency of 20, 40, 60 and 80V respectively. It was observed that the storey drift was ground, first and second floor was 0.42, 0.47 and 0.85, respectively at 60V. The numerical analysis was performed using ABAQUS finite element software incorporating concrete damage plasticity model and elasto-plastic model for concrete and reinforcement bar, respectively. The predicted storey drifts were found to be in good agreement with the experimental results corresponding to 60V. Further, the maximum peak positive acceleration predicted from the simulation was 4.72, 3.03 and 1.93g, respectively at the third (top), second (middle) and first slab (bottom), respectively.
Seismic Crack Analysis in Bridge
Authors: Sahu Lokesh , Mishra Abhishek
Published: June 2024

In 2008 Nepal earthquake, in a bridge was developed crack in girder. Displacement of the girder was also cause of earthquake. In bridge study earthquake motions records from close to the bridge site and motions inputs for the bridge’s time history analysis. Stresses of the girder are taken into account in the bridge model. Crack process and affects of crack held in discussion. For high stress zone different seismic inputs are taken. The result show that fracture develop when the girder’s tensile stress surpasses concrete tensile strength during earthquake excitations.
Seismic performance enhancement of base isolated RC building incorporating Cu-Al-Be and FNCATB based SMA
Authors: Baidya S , Roy B K
Published: June 2024

The introduction of smart materials used for enhancing the seismic performance of buildings has gained popularity in recent times. Shape memory alloy (SMA) is a classic example of smart material which is used to enhance performance and overcome various drawbacks of traditional base isolation systems such as the lack of recentering ability and very high isolator displacement which causes the pounding effect. SMA possesses a distinctive characteristic to endure exceptionally high levels of strain during the loading phase, and upon unloading the strain, no permanent deformation is perceived. In most of the studies and applications, nitinol (Ni-Ti) is used as SMA material. However, it has a higher manufacturing cost and is unable to retain its superelastic property in extremely low temperatures. Due to such limitations, different combinations of materials are studied and tested to be used as a replacement for Ni-Ti SMA and out of which copper-aluminium-beryllium (Cu-Al-Be) and a ferrous-based alloy (FNCATB) materials are significant as these SMAs are relatively less expensive to produce and also their superelasticity property is shown in a wide range of temperatures. So, in this study, the optimal seismic performance of a multi-storeyed base isolated RC building is evaluated under a set of real earthquake loads with these two SMAs. The base isolation is modelled in combination with rubber bearing and SMA (Cu-Al-Be and FNCATB), known as shape memory alloy rubber bearing (SMARB). The top floor acceleration and the isolator displacement are evaluated using these two types of SMAs and the responses are compared. The optimal values of normalized forward transformation strength of SMA materials (FS0
) are evaluated through a bi-objective optimization study to minimize the top floor acceleration as well as the isolator displacement of the isolated building. An evolutionary optimization algorithm, particle swarm optimization is used to solve the optimization problem. The results obtained in this study indicate that the Cu-Al-Be SMA is marginally more effective in reducing the isolator displacement and the FNCATB SMA performs more efficiently in controlling the top floor acceleration of the isolated building. The optimal value of FS0
is also higher for the Cu-Al-Be based SMARB isolation system.
Yield Line Analysis of Two Way Reinforced Concrete Slab of Three-Sides Supported with Various Loading Conditions
Authors: Kumar Shobhit , Rai Anjali , Jain Nitin
Published: June 2024

Yield line analysis is a powerful method used in structural engineering to evaluate the ultimate load-carrying capacity and failure mechanisms of reinforced concrete slabs. in this study finite element method is used to analyze three side supported(fixed) slab with concentrated loading on different location to find yield line pattern of slab. The finite element software Ansys is used to analysis the slab. this study performed on total five model or specimens. concentrated loading is positioned as-in centre of slab, shifted along central-line along the length, shifted along central-line transverse to the length.

ANSYS R2 is used to simulate and analyse the structural behaviour of different models. The analysis aimed to define the yield line pattern and compare the behavior of slab for different loading condition. Overall the objective of study structural behaviour and to find the yield line pattern of slab subjected to concentrated loading at different locations.
Treatment of Bamboo for Sustainable Construction Practise: A Comprehensive Review
Authors: Sain Amit , Gaur Arun , Khichad Jeetendra Singh , Somani Prakash
Published: June 2024

Bamboo is a versatile and sustainable natural resource that has been used for centuries by numerous cultures. Untreated bamboo, on the other hand, has limitations in terms of durability, strength, and decay resistance, which limit its usage in specific conditions. To overcome these restrictions and realise its full potential, researchers have investigated various bamboo treatment methods. This research presents an overview of bamboo treatment methods, effects on their performance, and emphasises possible uses in a variety of construction practises. The study looks into the usage of synthetic resin and synthetic rubber as bamboo protective coatings. These coatings improve durability, water repellence, dimensional stability, mechanical strength, and fungal growth resistance. They are also simple to use and contribute to environmentally friendly practises. To protect bamboo from fungal deterioration and insect infestation, chemical substances such as boron-based additions, zinc chloride, sodium pentachloro-phenate, and copper-chrome-arsenic (CCA) are employed as preservatives. These chemicals increase the longevity of bamboo while also ensuring its structural integrity. The use of epoxy resins to improve the tensile strength of bamboo composites is also being observed. It increases flexural and compressive strength by improving adhesion between bamboo fibres and the matrix. The use of epoxy glue also retains the natural strength and durability of bamboo. Heat treatment of bamboo entails treating it to high temperatures in order to enhance its qualities such as dimensional stability, hardness, and resistance to decay and insect assault. Heat-treated bamboo is used in building, furniture, flooring, and composite materials. Understanding and implementing these treatment procedures can help to encourage the wider use of bamboo as a sustainable and environmentally friendly construction material. The findings of this study have the potential to drive decision-making, encourage innovation, and have a positive impact on the environment, society, and economy. Bamboo may be used as a viable alternative to traditional materials in a variety of sectors by exploiting its unique qualities and improving its durability and strength.
Experimental study on mechanical characteristics of engineered cementitious composites (ECC) using bacillus pumilus
Authors: Solanki V P , Priyan K , Patel N A , Bhatt P M
Published: June 2024

Cementitious materials are the most common construction material globally. Even though deterioration cannot be prevented once the service life has begun, it still calls for maintenance and repair work, which is frequently labor and resource-intensive. Bacteria and fibres can be used to fix these issues. In this study, Bacillus pumilus bacteria is impregnated in concrete with 107 Cfu/g concentration. Glass fibres are used with 1% in ECC. To find mechanical characteristics like compressive, tensile, and flexural strength, tests were run at 7 and 28 days curing time intervals. The mechanical strengths of ECC are enhanced by the combination of fibres and bacteria due the high bridging ability, increase the bonding performance linking fibres, fill voids, enhances compactness.
Application of Waste Cooking Oil as a Rejuvenator for Aged Bitumen
Authors: Singhal Prachi , Gupta Archana Bohra
Published: June 2024

Bitumen/asphalt is used as a binder in flexible pavements. It is obtained from petroleum which is a non-renewable source of energy. Therefore, use of recycled asphalt pavement (RAP) is sustainable and economical as it replaces the fresh bitumen in the mix design. Stiffness of bitumen increases after aging due to environmental effects. Therefore, use of aged bitumen in construction of RAP causes increase in thermal crackling. To overcome this stiffening effect and to increase the self-healing properties of bitumen, certain materials in the form of rejuvenators can be added. Organic oils such as waste cooking oil (WCO) can be added to recycled bitumen to soften it by replacing lost maltenes and saturates. In this study, varying percentages of WCO are added to the RAP mix and its physical and rheological properties are evaluated by various tests. The results of the study indicate that properties of naturally aged bitumen and artificially aged bitumen improvise when waste cooking oil is added to them in a limited quantity. The addition of waste cooking oil as a rejuvenator improves properties of aged bitumen such as viscosity, softening point, penetration and ductility, but can decrease the Marshall stability of the mixture if too much WCO is added. The optimum range for adding WCO was found to be around 4% for thin film oven aged bitumen and around 6% for naturally aged bitumen. The rejuvenated material can be used in the construction of low-cost roads. Treatment of waste oils can also be done to remove the Free Fatty Acids (FFAs) from the waste oil. One such process applied in this study is the process of Transesterification. After testing, it was found that the properties didn’t vary substantially upon treatment of waste cooking oil. So, it is not recommended as it also increases the cost of the project.
Utilization of construction demolition waste as partial replacement in concrete: An experimental study
Authors: Semwal Ashish , Yadav Prince , Bano Samreen
Published: June 2024

The construction industry generates a significant amount of waste, which presents a significant challenge for waste management. This waste includes construction and demolition waste (CDW), crushed aggregate, mortar, crushed brick, stones, etc. Reusing and recycling these wastes can reduce waste disposal and save natural resources. This research paper explores the study of the combined replacement of recycled coarse aggregate (RCA) and recycled fine aggregate (RFA) with varying proportions and evaluates the feasibility and optimum proportion of waste material as a partial replacement. Mechanical properties such as compressive strength, split tensile strength, and flexural strength the of all specimens were tested as a combined replacement of RCA (0%, 25%, 50%, 75%, 100%) and RFA (0%, 10%, 20%, 30%, 40%) for M30 grade concrete. Furthermore, SEM, EDX, of mortar were analysed to determine the microstructure characteristics of the materials.
Comparative Study of PPC M40 Grade Bacterial Concrete (Bacillus Subtilis) & Conventional Concrete
Authors: Singh Himanshu Kumar , Rai Anjali , Jain Nitin
Published: June 2024

Concrete’s activity lifespan begins to decrease as soon as cracks begin to form, which are unavoidable regardless of mix design or formulation. Self-healing concrete by microbiologically induced calcium carbonate precipitation is one such method to prevent cracks from causing structural degradation because they gradually allow water and other materials to pass through. Numerous technologies and studies are being developed to address this issue. Concrete of this kind is capable of initiating biological activity autogenously and repairing itself. Experimental testing is done in this study to demonstrate how the Bacillus Subtilis bacteria affect the properties of PPC M40 grade concrete. The experiment consisted of comparing OPC (ordinary Portland cement), PPC (Portland pozzolana cement), and BACTERIA STIMULATED PPC CONCRETE of the same grade (M40). Bacteria (Bacillus subtilis) were used in PPC concrete in volumes of 10 ml, 20 ml, and 30 ml, with concentrations of 10^8 cells per ml, in order to determine the optimal dose for maximum strength. At 7 days, 14 days, and 28 days, samples of concrete were subjected to compressive strength, split tensile strength, and flexural strength tests. The experimental outcomes show that PPC-based bacteria(30ml) actuated substantially shows a limit of 30% increment in compressive strength, 29.88% increment in flexural strength and an 11.9% increment in split tensile strength than conventional concrete. The Scanning Electron Microscope (SEM) technique demonstrated the growth of nanoparticles of filler material that are calcite precipitates, which densifies the concrete and increases its strength. This confirmed the presence of calcite deposition.
Phase Changing Material (PCM) based envelope materials for energy efficient buildings
Authors: Yamini Sloka P , Amalan Sigmund Kaushik S
Published: June 2024

Phase Changing Materials (PCM) are innovative solutions in building design to regulate temperatures and reduce energy consumption. They offer diverse properties and can be incorporated through methods like direct incorporation, encapsulation, and more. Macro encapsulation is the prevailing trend due to its practicality and availability. This research undertakes a systematic literature review to examine the integration of PCMs with building envelopes, specifically focusing on various aspects across different climate zones in India. The primary objective is to investigate the macro encapsulation of PCMs and utilization in facades, analysing their performance in diverse Indian climate zones. The research compares incorporation methods, efficacy, advantages, and disadvantages, highlighting the relationship between PCMs and climate. Indian cities such as Delhi, Mathura, Ahmedabad, and Gurgaon are compared based on PCM selection, thermophysical properties, and incorporation techniques. The study emphasises the importance of proper macro encapsulation placement in building facades, considering weather conditions and direct sunlight. Lastly, the study provides a comprehensive overview of the limitations associated with different types of PCMs for building envelopes, drawing insights from specific examples in the Indian context. This research contributes to informed decision-making for architects, engineers, and policymakers seeking to enhance buildings’ thermal comfort and energy efficiency.
Development of sustainable pavement: an experimental study of stone mastic asphalt prepared with warm mix additives and reclaimed asphalt pavement
Authors: Kranthi Kiran Raj N , Ramesh A
Published: June 2024

Premature failures in flexible pavements, such as low-temperature stripping, medium-temperature fatigue cracking, and high-temperature rutting, pose significant challenges. In order to address these issues and environmental challenges, the use of Reclaimed Asphalt Pavement (RAP) mixtures surface layers is being encouraged. However, the utilization of RAP in surface layer as Stone Mastic Asphalt (SMA) SMA mixtures results into higher stiffness and fracture failure. In this context, experimental studies were conducted on SMA mixes with varying percentages of RAP (0%, 20%, 30%, and 40%) and cellulose fibers. Warm Mix Asphalt (WMA) technologies are also explored as an alternative to conventional Hot Mix Asphalt (HMA) to reduce energy consumption, carbon emissions, and ensure long-term sustainability.

The experimental approach involves the use of Polymer-Modified Binder (PMB 70) modified with warm mix additive and inclusion of cellulose fibers in SMA mixes so as to prevent asphalt drain down. The mixes were prepared using Marshall Mix design, and various techniques, including moisture susceptibility, rutting resistance and resilient modulus (RM) and were employed for comparison with control mixes.

The findings reveal that the SMA Mix containing 30% RAP exhibits superior resistance to moisture sensitivity and rut depth. Furthermore, the same mix displays significantly elevated resilient modulus values. Thus, the mix is showing promising results in mitigating premature failures and promoting more sustainable pavement solutions.
Behaviour of Masonry with Flyash Bricks
Authors: Mishra Renu , Kumar Praveen
Published: June 2024

Bricks will always be needed for construction, but as land use intensifies, soil for making bricks will become scarcer. Though fly ash bricks are available from last few years, but the experimental data regarding behaviour of masonry made with such bricks are limited. In the realm of structural design, the compressive strength of masonry stands as a crucial property, while the modulus of elasticity under uniaxial compression assumes equal importance, particularly when addressing concerns related to the deformation of masonry structures. The aim of the experimental investigation reported in this paper is to determine modulus of Elasticity (E) for fly ash brick masonry under axial compression through testing prisms with height to the least lateral dimension ratio of prisms between 2 to 4. Comparison of the same is reported with that of the masonry with conventional burnt clay bricks. The test results revealed that the strength and E of masonry with the alternative bricks (flyash) are in almost similar range to those with burnt clay bricks.
Characterisation of red mud as an embankment material for high-volume utilisations
Authors: Yashmin S S , Sinha A K
Published: June 2024

Red mud is an industrial by-product generated from the aluminium production industries while processing the bauxite ores to produce hydrated alumina. The global production of aluminium was approximately 140 million tonnes in 2022, generating almost 206 million tonnes of red mud (roughly 1.5 times), while 6.5 million tonnes of alumina and 9.1 million tonnes of red mud in India. Its utilisation in the field is eminently less than its humongous generation, leading to increased dumping on natural grounds. Hence, an attempt has been made to explore the feasibility of red mud for embankment construction, which is a high-volume utilisation. A comprehensive literature review has been carried out regarding the application of red mud in embankment construction. Physical and geotechnical properties were reported pertaining to embankment construction. The physical properties presented in the paper include viz. scanning electron microscope, Fourier transform infrared spectroscope and Raman spectroscopy. Geotechnical properties included in the paper are specific gravity, gradation, consistency limits, compaction, shear strength, permeability, and consolidation. The results obtained from the researchers have been compared among the different red mud obtained worldwide, including India. The geotechnical properties of different red mud were compared with the IRC/MoRTH/MoRD specifications. It was observed that it is an alternative to natural soil for embankment construction. It provides ample room for its utilisation in embankment construction, saving the natural soil and the landscapes that otherwise would turn into dumping grounds of red mud. This study aims to solve the dual challenges of waste management and sustainable development while exploring new possible utilisation of the material in the infrastructural development of the country.