scholarly journals RESEARCH OF STRUCTURAL DAMAGE IN THE HYOGOKEN-NANBU EARTHQUAKE : Estimation of seismic energy input based on damage of structures

1998 ◽  
Vol 63 (503) ◽  
pp. 165-170 ◽  
Author(s):  
Haruyuki KITAMURA ◽  
Takayuki TERAMOTO ◽  
Kunio UKAI ◽  
Katsuhide MURAKAMI ◽  
Hiroshi AKIYAMA ◽  
...  
Keyword(s):  
Structural Damage ◽  
Energy Input ◽  
Seismic Energy

Seismic Analysis and Design of RC Frame With New Metallic Dampers

2006 ◽  
Author(s):  
Hong-Nan Li ◽  
Gang Li
Keyword(s):  
Energy Dissipation ◽  
Structural Damage ◽  
Seismic Analysis ◽  
Traditional Approach ◽  
Seismic Energy ◽  
Analysis And Design ◽  
Good Ability ◽  
Metallic Dampers ◽  
Energy Dissipated ◽  
Metallic Damper

Earthquake can make structures damaged and crumble. The traditional approach to seismic design has been based upon providing a combination of strength and ductility to resist the imposed loads. Thus, the level of the structure security cannot be achieved, because the disadvantage of the designing method is lack of adjusting capability subjected to an uncertain earthquake. The presence of some damping (energy dissipation) in buildings has been recognized and studied by professional researchers. Passive energy-dissipated system, as a category of vibration control methods, lead the inputting energy from earthquake to special element, thereby reducing energy-dissipating demand on primary structural members and minimizing possible structural damage. In this paper, a new idea of designing metallic damper is presented and realized through the improved dampers that are of a certain bearing forces in plane of plate and suitable energy-dissipating capability by making metallic dampers in different shapes. New types of metallic dampers are called as “dual functions” metallic damper (DFMD), because it not only provides certain stiffness in normal use for a building, but also are of good ability of the seismic energy-dissipation. The structural configuration and mechanical characteristics of the models and prototypes of the DFMDs are analyzed and experimented so as to verify the seismic performance of the dampers. Finally, the DFMDs applied to a new building in China are introduced and numerical results demonstrate the effectiveness of the DFMD.

scholarly journals Experimental Campaign of a Low-Cost and Replaceable System for Passive Energy Dissipation in Precast Concrete Structures

2020 ◽  
Vol 10 (4) ◽  
pp. 1213 ◽  
Author(s):  
Álvaro Mena ◽  
Jorge Franco ◽  
Daniel Miguel ◽  
Jesús Mínguez ◽  
Ana Carla Jiménez ◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Structural Damage ◽  
Low Cost ◽  
Precast Concrete ◽  
Seismic Energy ◽  
Structural Wall ◽  
Residential Structures ◽  
Energy Dissipation System ◽  
Seismic Tests ◽  
Dissipation System

This research develops a new low-cost energy dissipation system, capable of being implemented in residential structures in developing countries with high seismic activity, in which the current solutions are not economically viable. These residential structures are entirely made of precast concrete elements (foundations, walls, and slabs). A solution is developed that consists of a new connection between a precast foundation and a structural wall, which is capable of dissipating almost all the seismic energy, and therfore protecting the rest of the building from structural damage. To validate the solution, a testing campaign is carried out, including a first set of “pushover” tests on isolated structural walls, a second set of “pushover” tests on structural frames, and a final set of seismic tests on a real-scale three-storey building. For the first and second set of tests, ductility is analyzed in accordance with ACI 374.2R-13, while for the third one, the dynamic response to a reference earthquake is evaluated. The results reveal that the solution developed shows great ductility and no relevant damage is observed in the rest of the building, except in the low-cost energy dissipation system. Once an earthquake has finished, a precast building implemented with this low-cost energy dissipation system is capable of showing a structural performance level of “immediate occupancy” according to ACI 374.2R-13.

Seismic energy transmission to deep-founded structures

1971 ◽  
Vol 61 (3) ◽  
pp. 781-787
Author(s):  
Colin B. Brown
Keyword(s):  
Beneficial Effect ◽  
Shear Wave ◽  
Rayleigh Waves ◽  
Energy Input ◽  
Seismic Energy ◽  
Energy Transmission ◽  
Seismic Input ◽  
Wave Velocities ◽  
Shear Wave Velocities ◽  
Low Shear

abstract The predominant seismic energy input into structures is from Rayleigh waves. These attenuate rapidly with distance from the surface and are partially reflected and partially transmitted by a hole in the ground. A structure founded in such a hole may anticipate a smaller seismic input than a surface-founded structure. Estimates of such a reduction are given which indicate that only short buildings and material with low shear-wave velocities will provide the proper conditions for this beneficial effect.

Post-earthquake fast damage assessment using residual displacement and seismic energy: Application to Mexico City

2021 ◽  
pp. 875529302110218
Author(s):  
Pablo Quinde ◽  
Amador Terán-Gilmore ◽  
Eduardo Reinoso
Keyword(s):  
Mexico City ◽  
Structural Damage ◽  
Residual Deformation ◽  
Seismic Energy ◽  
Field Evaluation ◽  
Quantitative Information ◽  
Maximum Displacement ◽  
Residual Displacement ◽  
Plastic Energy ◽  
Earthquake Assessment

The simplicity, timeliness, and reliability of a post-earthquake assessment are fundamental for decision-makers in emergency management. An adequate risk assessment will help during the recovery and, therefore, increases the resilience of the community. Although within this context, the walk-down damage survey with the correct filling of evaluation forms and use of processing-data tools make possible a pertinent post-earthquake assessment, it is desirable to have measurable parameters that can complement the visual field evaluation with quantitative information. In some cases, basic quantitative measures, such as crack width, are not enough to make pertinent structural damage assessments. This article presents a fast and simple methodology to estimate the median maximum displacement and plastic energy demands on simple single-degree-of-freedom systems from the residual displacement they exhibit after being subjected to ground motions generated in the lakebed zone of Mexico City. Based on this, a discussion is offered on how a post-earthquake assessment can be improved by complementing the visual and measured information gathered on an existing structural system after an intense ground motion, with estimates of its maximum and cumulative plastic deformation demands derived from its residual deformation.

Characteristics of Earthquake Input Energy of a Subway Station Structure Based on Probability Density Evolution Method

2020 ◽  
pp. 2041014
Author(s):  
Z. Q. Liu ◽  
Z. Y. Chen ◽  
H. Zhao
Keyword(s):  
Probability Density ◽  
Energy Input ◽  
Underground Structure ◽  
Seismic Energy ◽  
Stochastic Methods ◽  
Underground Structures ◽  
Density Evolution ◽  
Probability Density Evolution Method ◽  
Dissipation Mechanism ◽  
Probability Density Evolution

Understanding seismic energy input and dissipation mechanism is necessary for energy-based seismic design of complex underground structures. Due to the intrinsic uncertainty of ground motion, stochastic methods are usually needed. In this paper, we study the seismic energy input and dissipation mechanism in an underground structure using the probability density evolution method (PDEM). It is found that the cumulative hysteretic energy dissipation ([Formula: see text] of the underground structure is reduced by 55% compared with the above-ground structure due to soil constraint. The columns, walls and slabs at the bottom of the underground structure have a high demand for [Formula: see text], which are vulnerable spots of the structure.

scholarly journals Unbonded Post-tensioned Precast Concrete Walls With Rocking Connections: Modeling Approaches and Impact Damping

2021 ◽  
Vol 7 ◽  
Author(s):  
Dimitrios Kalliontzis ◽  
Maryam Nazari
Keyword(s):  
Structural Damage ◽  
Precast Concrete ◽  
Seismic Energy ◽  
Shake Table Tests ◽  
Modeling Approaches ◽  
Supplemental Damping ◽  
Rocking Walls ◽  
Rocking Wall ◽  
Wall System ◽  
Impact Damping

Over the past two decades, precast concrete members have been utilized in seismically resilient structures. In developing these structures, different techniques have been used for connecting the precast members to the foundation. In building construction, unbonded post-tensioning (PT) tendons can anchor a precast wall to the foundation, resulting in the so-called rocking wall system. The rocking wall system develops a dry connection with the foundation and provides moment resistance by means of the PT tendons. The PT tendons remain elastic when the wall is subjected to design-level ground motions to preserve the re-centering capability of the wall. Moreover, the structural damage is concentrated near the wall toes and can be minimized with proper detailing of the toes. Rocking wall systems can consist of a Single precast Rocking Wall (SRW), which uses no supplemental damping, or walls with supplemental damping in the form of viscous or hysteretic energy dissipating devices. In addition to the supplemental damping, rocking walls dissipate the seismic energy through their impacts on the foundation base, their inherent viscous damping, and the hysteresis of concrete near the wall base. While the investigation of rocking walls continues to gain interest, there is no widely accepted means of modeling their dynamic behavior. This paper investigates two popular approaches for modeling rocking walls with and without supplemental damping: the finite element method and analytical modeling. The ability of the two approaches to capture the local and global responses of the walls is evaluated against shake table tests of walls with multiple-level intensity base motions. Next, the behavior characteristics of the two modeling approaches and their ability to simulate impact damping are discussed.

Estimating Seismic Energy in Structure with Wavelet Transform

2010 ◽  
Vol 163-167 ◽  
pp. 3958-3963
Author(s):  
Mei Ling Xiao ◽  
Liao Yuan Ye ◽  
Yun Fen Li ◽  
Yan Li
Keyword(s):  
Wavelet Transform ◽  
Energy Input ◽  
Wavelet Coefficient ◽  
Ground Motions ◽  
Linear Structure ◽  
Seismic Energy ◽  
Acceleration Process ◽  
Single Degree Of Freedom ◽  
Single Degree ◽  
Time Histories

This study proposed a wavelet method for estimating seismic energy in single-degree-of-freedom (SDOF) structure. With the recent development of wavelet-based procedures for structure seismic response, which the displacement and velocity of linear SDOF structure can be expressed with wavelet transform of acceleration process, it is easy to estimate seismic energy in SDOF linear structure, and strain, kinetic, damping energy and energy input based on wavelets introduced in a range of time and frequency assigned to the wavelet coefficient, Expressions have been derived for (i) the equation of motion. (ii)the wavelet coefficients of the response processes. By using these principles, a linear SDOF structure which subjected to 1988 LanCang-GenMa earthquake ground motions is analyzed, time-histories of strain, kinetic, damping energy and energy input for various ranges of frequencies are identified.

Earthquake-Resistant Design of RC Frame With “Dual Functions” Metallic Dampers

2007 ◽  
Author(s):  
Hong-Nan Li ◽  
Gang Li
Keyword(s):  
Energy Dissipation ◽  
Inelastic Deformation ◽  
Structural Damage ◽  
Seismic Energy ◽  
Good Ability ◽  
Out Of Plane ◽  
Metallic Dampers ◽  
Metallic Damper ◽  
Dual Functions ◽  
Metallic Plates

Earthquake can make structures damaged and crumble. The traditional approach to seismic design has been based upon providing a combination of strength and ductility to resist the imposed loads. Thus, the level of the structure security cannot be achieved, because the disadvantage of the designing method is lack of adjusting capability subjected to an uncertain earthquake. The presence of some damping (energy dissipation) in buildings has been recognized and studied by professional researchers. Passive energy-dissipated system, as a category of vibration control methods, lead the inputting energy from earthquake to special element, thereby reducing energy-dissipating demand on primary structural members and minimizing possible structural damage. One of the most effective mechanisms available for the dissipation of input energy of a structure during an earthquake is through the inelastic deformation of metallic substances. Added damping and stiffness (ADAS) elements are designed through the flexural yielding deformation of steel plates. Metallic material is a popular (and inexpensive) choice for an energy dissipation device because of its relatively high elastic stiffness, good ductility and its high potential for dissipating energy in the post-yield region. The idea of utilizing separate metallic dampers in a structure to absorb a large portion of the seismic energy began with the conceptual and experimental work by Kelly et al.. Numerous different types of energy-absorbed devices have been proposed, for example, X-shaped and triangular plate dampers by Whittaker et al. The normal metallic damper is to use the out-of-plane bending deformation of metallic plate to provide damping for structure to reduce its dynamic response to environmental loadings. Since the bending curvature produced by a force, which is perpendicular to the metallic plates of damper applied at the ends is uniform over the full height of the plate, the plate can inelastically deform well without deflection concentration. However, the inelastic deformation of the damper may occur even subjected to a relatively small disturbance (wind or earthquake) since the out-of-plane stiffness of metallic plates of damper is very small. As a result, it has to be replaced after the disturbance. How to improve the stiffness of metallic dampers is an important issue. In this paper, a new idea of designing the metallic damper is presented, i.e. the metallic damper with “dual functions”, and the quasi-static tests with the dampers are carried out. Design and fitting process of the reinforced concrete frame with dual functional metallic damper are introduced. A three-dimensional frame structure model is made with ADPL language in ANSYS program. Seismic responses of the structure with and without metallic damper are calculated and compared. The results show that the metallic dampers with the “dual functions” presented here not only provide certain stiffness in the normal application, but also are of good ability of the seismic energy dissipation.

Seismic Energy Demands in Steel Moment Frames

2016 ◽  
Vol 847 ◽  
pp. 210-221
Author(s):  
Selcuk Dogru ◽  
Bora Aksar ◽  
Bulent Akbas ◽  
Jay Shen ◽  
Onur Seker ◽  
...  
Keyword(s):  
Ground Motion ◽  
Structural Damage ◽  
Seismic Energy ◽  
Degree Of Freedom ◽  
Nonlinear Time History Analysis ◽  
Input Energy ◽  
Moment Frames ◽  
Steel Moment Frames ◽  
Energy Parameters ◽  
Energy Demands

This study presents an energy approach to the seismic evaluation of steel moment resisting frames. A structure subjected to strong ground motion is supposed that it shows nonlinear behavior. Energy parameters is a way to specify the structural damage. Input energy is depend on the characteristics of the structure and ground motion. Structural design can be defined as the equilibration of the input energy and the energy dissipation capacity of the structure. Structures subjected to eartquake are supposed to dissipate all the input energy. Studies based on energy concepts are usually applied to single-degree-of-freedom (SDOF) system. For multi-degree-of-freedom (MDOF), more researches and new simpler methodologies are still needed in performance based evaluation including energy parameters. In this study , low – medium and high rise steel moment frames and will be studied in linear and nonlinear time history analysis. The results obtained from these analysis are reviewed for seismic energy demands.

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