Seismic and Wind Analysis of RCC Building with Different Shape of Shear Wall and Without Shear Wall

In India, about 50-60% of the total area is vulnerable to the seismic activity. Earthquakes are the vibrations or the motion of the ground due to release of energy. The vibrations or ground motion are the important factors to analyze and design, the earthquake resistant structure. So, to reduce the impact of earthquake different efforts has been done in this field. Basically, earthquake exerts lateral as well as vertical forces so to dissipate those forces and the vibration in system earthquake resistant structure has been design. The design of earthquake resistant structures depends on providing stiffness, strength and inelastic deformation which withstand the earthquake forces. As the height of the structure increases the lateral loads acted on the structure increases and decrease in the stiffness, so to counteract those shear walls and different damping devices has been used. Keywords: IS Code 1892-Part-1:2016; U - Section, Z- Section, H-Section, T-Section

Normalized Ratcheting Diagram Under Sinusoidal Vibration Waves

Ratcheting is a progressive incremental inelastic deformation or strain which can occur in a component that is subjected to variations of mechanical stress, thermal stress, or both. This study concentrated on the ratcheting occurrence of the piping model under the combined effect of constant external force and dynamic cyclic vibrations. Bent solid bars represented piping models, and sinusoidal acceleration waves were loaded. Characteristics of seismic loads between load-controlled and displacement-controlled properties were studied from the viewpoint of the frequency ratio of the forcing frequency to the natural frequency of the piping model. Besides, the ratcheting occurrence conditions of the beam and the piping model were compared in one normalized diagram to display the general mechanism of ratcheting with the consideration of the effect from the difference of shape and material. Results show that ratcheting occurs easily with a lower frequency ratio in both beam and piping models. In addition, it is meaningful to use beam models to understand the ratcheting mechanism of piping models. Describing the occurrence of ratcheting using the normalized ratcheting diagram for different components is feasible.

A compilation and characterisation of lithics in kimberlite and common maar-diatremes and tephra ring deposits

Maar-diatreme volcanoes are the second-most common type on land, occurring in volcanic fields within all major tectonic environments. Their deposits typically contain an abundance of lithic fragments quarried from the substrate, and many contain large, deep-sourced lithic fragments that were erupted to the surface. Primary volcaniclastic deposits fill the diatreme structure formed during eruption. There is negligible inelastic deformation of diatreme-adjacent country rock, indicating that country rock is removed to create the diatreme structures, either by being shifting downward below observable levels, ejected upward to contribute to surficial deposits, or dissolved and hidden in magma erupted or intruded at depth. No previous study has systematically reviewed and analysed the reported lithic fragments of maar-diatreme systems. We present a comprehensive compilation from published work of lithic characteristics in maar ejecta rings and in diatreme deposits of both common and kimberlite maar-diatremes. For maar-diatremes and their tephra ring deposits, we find no correlations among lithic clast sizes, shapes, depositional sites, and excavation depths. This is difficult to reconcile with models involving systematic diatreme deepening coupled with tephra-ring growth, but consistent with those involving chaotic explosions and mixing. Larger amounts of data are needed to further examine how these types of volcanoes operate.

Effect of reverse thermoelastic phase transformation on stress of onset of structural deformation in titanium nickelide

The experimental study results of the dependence in the stress value of the onset of the structural deformation on the degree of the reverse phase transformation occurring after the complete direct martensitic transformation in titanium nickelide are described. It is established that these results are qualitatively and quantitatively correctly described in the framework of the model according to which the maximum value of the intensity of the intrinsic inelastic deformation of the martensitic part of the representative volume of the shape-memory alloy is used as a parameter of isotropic hardening.

Infrasonic Nanocrystal Formation in Amorphous NiTi Film: Physical Mechanism, Reasons and Conditions

The physical mechanism, reasons and conditions of nanocrystal formation in an amorphous NiTi metal film, stimulated by infrasonic action, are formulated. Nanostructural elements of an amorphous medium (relaxation centers) containing disordered nanoregions with two-level systems are considered to be responsible for this process. When exposed to infrasound, a large number of two-level systems are excited, significantly contributing to inelastic deformation and the formation of nanocrystals. The physical mechanism of the nanocrystallization of metallic glass under mechanical action includes both local thermal fluctuations and the additional quantum tunneling of atoms stimulated by shear deformation. A crystalline nanocluster appears as a result of local atomic rearrangement growing increasingly exposed to infrasound. It is possibly unstable in the absence of infrasound. When the radius of the nanocluster reaches a critical value, a potential well appears, in which a conducting electron is localized to form a phason (stable nanocrystal). Estimated values of the phason’s radius and the depth of the nanometer potential well is about 0.5 nm and 1 eV, respectively. It forms a condition of stable phason formation. The occurrence of the instability of the amorphous state and following transformation to the nanostructured state is based on the accumulation of the potential energy of inelastic deformation to a critical value equal to the latent heat of the transformation of the amorphous state into the nanostructured state.

A Compilation and Characterisation of Lithic Populations in Common and Kimberlite Maar-Diatremes and their Tephra Ring Deposits

Maar-diatreme volcanoes are the second-most common type on land, occurring in volcanic fields within all major tectonic environments. Their deposits typically contain an abundance of lithic fragments quarried from the substrate, and many contain large, deep-sourced lithic fragments that were erupted to the surface. Primary volcaniclastic deposits fill the diatreme structure formed during eruption. There is negligible inelastic deformation of diatreme-adjacent country rock, indicating that country rock is removed to create the diatreme structures, either by being shifting downward below observable levels, ejected upward to contribute to surficial deposits, or dissolved and hidden in magma erupted or intruded at depth. No previous study has systematically reviewed and analysed the reported lithic fragments of maar-diatreme systems. We present a comprehensive compilation from published work of lithic characteristics in maar ejecta rims and in diatreme deposits of both common and kimberlite maar-diatremes. For maar-diatremes and their tephra ring deposits, we find no correlations among lithic clast sizes, shapes, depositional sites, and excavation depths. This is difficult to reconcile with models involving systematic diatreme deepening coupled with tephra-ring growth, but consistent with those involving chaotic explosions and mixing. Larger amounts of data are needed to further examine how these types of volcanoes operate.

Inelastic Deformation of Copper Nanoparticle Based Joints and Bonds

The inelastic deformation properties of sintered metal nanoparticle joints are complicated by the inherent nanocrystalline and nanoporous structures as well as by dislocation networks formed in sintering or under cyclic loading. Creep rates of sintered nanocopper structures were found to be dominated by the diffusion of individual atoms or vacancies, while dislocation motion remained negligible up to stresses far above those of practical interest. Rapid sintering of one material led to unstable structures the creep of which could be strongly reduced by subsequent annealing or aging. Longer sintering of another material led to more stable structures, but creep rates could still be strongly enhanced by subsequent work hardening in mild cycling.

Molecular Dynamics Simulations of Titanium Dioxide as Model System for Size Effects in Aerosol Deposition

Up to now, the role of particle sizes on deformation features of ceramic particles in aerosol deposition (AD), is not fully understood. For distinguishing general features, two-dimensional molecular dynamics (MD) simulations are applied to study associated phenomena. The nanoparticles are assumed to have original sizes of 10-300 nm and to impact the substrate at velocities of 100-800 m/s. The applied Lennard-Jones potential for the modelled nanoparticles were adjusted to mimic the mechanical properties of TiO2-anatase. For small particles, the simulations reveal three different impact behaviors of (i) rebounding, (ii) bonding and (iii) fragmentation based on initial size and impact velocity, whereas, the larger ones do not show the bonding behavior. The upper limit of the bonding regime shrinks with increasing particle sizes, the field then diminishing for the largest ones. The different impact phenomena were analyzed by evolution of the stress, strain and temperature fields. Stress and strain field results showed that “localized inelastic deformation” occurred at particle sites spreading from the interface to the substrate to the particle core. Calculated temperature fields show a local rise of around 1200 Kelvin due to the inelastic deformation, which is probably sufficient for thermal activation of further deformation features.