Magnitude Of Horizontal Displacement Research Articles

Multi-Story Volumetric Blocks Buildings with Lower Frame Floors

This article presents the results of experimental studies of the stress–strain state of volumetric blocks based on the underlying frame structures. The aim of the research is to evaluate the stress–strain state and the nature of damage development as a result of an increase in the load up to a critical level. Based on the analysis of the nature of the damage, recommendations have been developed to strengthen the destruction zone. Data were collected on the redistribution of stresses and deformations, the formation of cracks and joint openings, the magnitude of horizontal displacements, and the failure mode of volumetric blocks and floor frames. Five full-scale volumetric blocks were tested under the loading of hydraulic jacks, differing in concrete type, reinforcement, presence of doors, and dimensions of the stylobate beams. When the volumetric modules were supported by a frame floor the results revealed that the maximum destructive load of 10,462 kN was observed in the first specimen; the horizontal displacements of the walls decreased by 13–18 mm, and there was a decrease in the crack opening width to 0.5 mm. The cracks decreased the strength of the walls, leading to a redistribution of the compressive stresses and their increase in the support zone. The most significant compressive strains in concrete in the corner parts of longitudinal walls were in the range of (600–620) × 10−6, and in the middle part of the walls, 370 × 10−6 were observed. Furthermore, the largest cracks caused significant horizontal displacements (deplanation) of the walls, which decreased the stiffness of the conjunction of longitudinal walls with the floor slab and created an additional eccentricity of the vertical force. Based on the findings, the correlation between the measured parameters of each specimen at all stages of vertical load increase is demonstrated and illustrated in graphs of the measured parameters. The importance of quantity compliance with the initial rigid connection between the longitudinal wall and ceiling plate has been estimated.

Structural Styles of Thrust Zones of the Urals and Pay-Khoi Foredeep

The article presents an interpretation of geophysical data characterizing the structure of the frontal fold and thrust zones of the Urals and Pay-Khoi, which show the diversity of structural styles of deformations in the study region. The following structural styles of deformations are considered: classical-style thrust zones, which are in-sequence thin-skinned imbrication systems (i); areas of distribution of wedge-shaped allochthons, composed of duplex tectonic plates that are not reflected in the sub-surface layers (ii); inversion zones where faults associated with Ural rifting are transformed into thrust faults (iii); areas whose structure is determined by the deformation of salt diapirs and extrusion of salt (iv); zone, tectonic thickening of the Precambrian complexes overlain by the Paleozoic cover (v). Interpretation of historical and new data on the structure of fold belts makes it possible to significantly update understanding of the structure and development of areas such as zones of wedge-shaped thrusts, areas of development of squeezed salt diapirs, and areas where reactivation and tectonic thickening of Precambrian complexes occurred due to the reactivation of pre-existing faults. New seismic data provided constraints on the magnitude of horizontal displacements in the thrust zones as well as timing of shortening. For the first time they have revealed the development of arrays of small-scale protothrusts.

A FEM-BEM interactive coupling for modeling the piezoelectric health monitoring systems

In this research, finite element and boundary element methods are coupled together to model the interaction of a piezoelectric ceramic working as an actuator with an elastic material. Piezoelectric-elastic material's interaction occurs in smart structures. This work is aimed at determining the actuation effects being transferred from the actuators to the host and the resulting overall structural response. To obtain the amount of these actuations, the system of the host structure and an actuator has been modeled by using coupled finite element boundary element method in frequency domain. The host structure, which is assumed as an isotropic elastic solid region is modeled as a half space. The piezoelectric ceramic region is modeled by the 3-D finite element method, while the elastic half space with boundary element method. Finite element model of piezoelectric ceramic and boundary element model of the elastic half space are coupled together at their interface such that the vibrations of the piezo-actuator induce vibrations in the elastic half space. A couple of examples are given to show the induced displacement field around the piezo-actuator on the surface of the elastic medium. The results show that high jump in magnitude of horizontal displacements at the corners of the actuator attached to the structure occurs, which is an indication of high stress concentration, of the shear stress type at the corners. This stress concentration sometimes causes complete debonding of the actuator from the base structure. By using the suggested BEM-FEM coupled model for actuators with different dimensions or material properties much useful information concerning the amount of actuation and load transfer can be obtained. The presented work is a step towards modeling of structural health monitoring systems.