scholarly journals Effects of Shape Memory Alloys on Response of Steel Structural Buildings within Near Field Earthquakes Zone

2020 ◽  
Vol 6 (7) ◽  
pp. 1314-1327
Author(s):  
Mahmoud Ahmadinejad ◽  
Alireza Jafarisirizi ◽  
Reza Rahgozar
Keyword(s):  
Shape Memory Alloys ◽  
Shape Memory ◽  
Base Isolation ◽  
Near Field ◽  
Seismic Zone ◽  
Isolation System ◽  
Residual Displacements ◽  
Rubber Bearing ◽  
Laminated Rubber Bearing ◽  
Isolation Systems

Base isolation is one of the effective ways for controlling civil engineering structures in seismic zone which can reduce seismic demand. Also is an efficient passive control mechanism that protects its superstructure during an earthquake. However, residual displacement of base-isolation systems, resulting from strong ground motions, remain as the main obstacle in such system’s serviceability after the earthquake. Shape Memory Alloys (SMA) is amongst the newly introduced smart materials that can undergo large nonlinear deformations with considerable dissipation of energy without having any permanent displacement afterward. This property of SMA may be utilized for designing of base isolation system to increase the structure’s serviceability. Here, a proposed semi-active isolation system combines laminated rubber bearing system with shape memory alloy, to take advantage of SMAs high elastic strain range, in order to reduce residual displacements of the laminated rubber bearing. Merits of the system are demonstrated by comparing it to common laminated rubber bearing isolation systems. It is found that the optimal application of SMAs in base-isolation systems can significantly reduce bearings’ residual displacements. In this study, OpenSees program for a three dimensional six-storey steel frame building has been used by locating the isolators under the columns for investigating the feasibility of smart base isolation systems, i.e., the combination of traditional Laminated Rubber Bearing (LRB) with the SMA, in reducing the structure’s isolated-base response to near field earthquake records are examined. Also, a new configuration of SMAs in conjunction with LRB is considered which make the system easier to operate and maintain.

Design of Shape Memory Alloy Damper for Base Isolated Structure

1997 ◽  
Author(s):  
Krzysztof Wilde ◽  
Paolo Gardoni ◽  
Yozo Fujino ◽  
Stefano Besseghini
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Base Isolation ◽  
Hysteretic Behavior ◽  
Isolation System ◽  
Rubber Bearing ◽  
Laminated Rubber Bearing ◽  
Base Isolation System ◽  
Rubber Bearings ◽  
Smart Base Isolation

Abstract Base isolation provides a very effective passive method of protecting the structure from the hazards of earthquakes. The proposed isolation system combines the laminated rubber bearing with the device made of shape memory alloy (SMA). The smart base isolation uses hysteretic behavior of SMA to increase the structural damping of the structure and utilizes the different responses of the SMA at different levels of strain to control the displacements of the base isolation system at various excitation levels. The performance of the smart base isolation is compared with the performance of isolation by laminated rubber bearings to assess the benefits of additional SMA damper for isolation of three story building.

scholarly journals The effect of seismic base isolation on structural response of a 12-story hotel building in Padang, Indonesia

2020 ◽  
Vol 156 ◽  
pp. 05026
Author(s):  
Fauzan ◽  
Afdhalul Ihsan ◽  
Mutia Putri Monika ◽  
Zev Al Jauhari
Keyword(s):  
Base Isolation ◽  
Response Spectrum ◽  
Soft Soil ◽  
Structural Response ◽  
Time History ◽  
Seismic Zone ◽  
Isolation System ◽  
Rubber Bearing ◽  
Seismic Base Isolation ◽  
The City

The amount of potential investment in Padang City, Indonesia since 2017 attracted many investors to contribute to the city. One of the investments is a 12-story hotel that will be constructed in By Pass Street of the city. The hotel is located in a high seismic zone area, so the seismic base isolation has been proposed to be used in the hotel building. The main aim of using a seismic base isolation device is to reduce the inertia forces introduced in the structure due to earthquakes by shifting the fundamental period of the structure out of dangerous resonance range and concentration of the deformation demand at the isolation system. An analytical study on the Reinforced Concrete (RC) hotel building with and without rubber bearing (RB) base isolation is carried out using the response spectrum and time history analysis methods. The results show that internal forces and inter-story drift of the building with high damping rubber bearing (HDRB) are lower than that of the fixed base with a remarkable margin. From this study, it is recommended to use the HDRB base isolation for medium and high rise buildings with soft soil in Padang City, Indonesia.

Effects of Damper Force Ranges and Ground Motion Pulse Periods on the Performance of Semi-Active Isolation Systems

2003 ◽  
Author(s):  
Henri Gavin ◽  
Julie Thurston ◽  
Chicahiro Minowa ◽  
Hideo Fujitani
Keyword(s):  
Ground Motion ◽  
Large Scale ◽  
Base Isolation ◽  
Near Field ◽  
Shaking Table ◽  
Isolation System ◽  
Active Isolation ◽  
Isolation Systems ◽  
Fail Safe ◽  
Strong Ground

A large-scale base-isolated steel structural frame was tested at the shaking table laboratory of the National Research Institute for Earth Sciences and Disaster Prevention. These collaborative experiments featured auto-adaptive media and devices to enhance the performance of passive base isolation systems. The planning of these experiments involved determining appropriate device control methods, the development of a controllable damping device with fail-safe characteristics, and the evaluation of the performance of the controlled isolation system subjected to strong ground motion with pronounced near-field effects. The results of the planning study and their large-scale experimental confirmation provide guidelines for the development and implementation of auto-adaptive damping devices for full scale structures.

Seismic Evaluation of Base Isolated System Equipped with Shape Memory Alloys

2013 ◽  
Vol 831 ◽  
pp. 110-114
Author(s):  
S. Alvandi ◽  
M. Ghassemieh
Keyword(s):  
Shape Memory Alloys ◽  
Shape Memory ◽  
Seismic Isolation ◽  
Passive Control ◽  
Structural Model ◽  
Base Isolation ◽  
Base Shear ◽  
Seismic Evaluation ◽  
Isolation System ◽  
Base Isolation System

Seismic isolation system is an example of passive control system that effectively improves the performance of structures. This research discusses the seismic performance of a elastomeric base isolation system which provide the combined features of vertical load support, horizontal flexibility and energy absorbing capacity, utilizing shape memory alloys that provides re-centering force and additional damping in the system. Also this paper compares the effect of such alloys with memory effect and/or superelasticity (with pre-straining) in base isolated structure. To provide such comparison, a nonlinear structural model has been developed on some benchmark control problems and some health monitoring evaluation criterias are used. The smart base isolation utilizes the different responses of shape memory alloys at several levels of strain to control the displacements of the rubber bearing and base shear at excitation level. Furthermore the proposed based isolation systems has enhanced performance in terms of response reduction and re-centering capacity.

scholarly journals Mitigation of Earthquake Responses Using SMA Supplemented Base-Isolation Devices for Benchmark Building

2021 ◽  
Vol 2 (4) ◽  
pp. 22-30
Author(s):  
Ashish R. Akhare
Keyword(s):  
Degrees Of Freedom ◽  
Base Isolation ◽  
Near Field ◽  
Evaluation Criteria ◽  
Time History ◽  
Base Shear ◽  
Comparative Performance ◽  
Isolation System ◽  
Seismic Control ◽  
Isolation Systems

The efficiency of traditional isolation bearings is doubted for near-field earthquakes because these bearings undergo large displacement. A comparative study of different base isolation systems of base-isolated benchmark building is carried out in the present study. The study is based on assumption that buildings are bi-directionally acted upon by near-field earthquakes for assessing their relative performance in seismic control of the benchmark building. The time history variations of important response parameters and evaluation criteria of the benchmark building has been studied for assessing the effectiveness of the isolation systems. The Shape Memory Alloy (SMA) is utilized with elastomeric bearings and friction bearings to study the effectiveness of SMA wires with different isolators. The benchmark building is modelled as a discrete linear elastic shear structure having three degrees of- freedom at each floor level. Time domain dynamic analysis of this building has been carried out with the help of constant average acceleration Newmark’s method and equilibrium of non-linear forces has been taken care by fourth order Runge-Kutta method. The comparative performance of various isolation systems has been studied with uniform and hybrid combinations. The hybrid combination of SMA supplemented bearings works out the better isolation system keeping in view of the percentage reduction in evaluation criteria for smart base-isolated benchmark building. Furthermore, it is shown that, the functionality of SMA wire is not efficient with Lead Rubber Bearing system, as it is able to control displacement but increases the acceleration, base shear, story drift and isolation forces.

Finite-Element Analysis of Laminated Rubber Bearing Used in Base-Isolation System

1992 ◽  
Vol 65 (1) ◽  
pp. 46-62 ◽  
Author(s):  
Mineo Takayama ◽  
Hideyuki Tada ◽  
Ryuichi Tanaka
Keyword(s):  
Finite Element ◽  
Energy Density ◽  
Strain Energy Density ◽  
Strain Energy ◽  
Base Isolation ◽  
Isolation System ◽  
Strain Energy Density Function ◽  
Rubber Bearing ◽  
Laminated Rubber Bearing ◽  
Base Isolation System

Abstract A realistic mechanical model was proposed for the laminated rubber bearing, one of the most important structural members in the base-isolation system. The model was analyzed by means of the finite-element method (FEM), up to the range of large deformation under high compressive load. The physical characteristics of the rubber material was modeled using a strain-energy-density function based on the biaxial elongation tests. The load-deformation relationship calculated by FEM using such strain-energy-density function agreed well with experimental results. Based on the simulated stress and strain distributions in the laminated rubber bearing, a mechanism of supporting the vertical load during horizontal deformation was proposed.

The Seismic Response Analysis of Isolation Structure with Shape Memory Alloy Re-Centring Dampers

2011 ◽  
Vol 99-100 ◽  
pp. 81-90
Author(s):  
Xiao Yu Miao ◽  
She Liang Wang ◽  
Yu Jiang Fan
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Seismic Response ◽  
Time History ◽  
Response Analysis ◽  
Property A ◽  
Isolation System ◽  
Rubber Bearing ◽  
History Analysis ◽  
Laminated Rubber Bearing

Shape memory alloy (SMA) is provided with preferable damp capacity at pseudo-elasticity state, applying this property, a SMA re-centring damper is introduced by some scholars. In this paper, the new isolation system combining the above damper with laminated rubber bearing is proposed, so as to obtain preferable isolation character and re-centring capacity. To illustrate the feasibility and effectiveness of the proposed system, the following work is done: First, according the constitution model of SMA at pseudo-elasticity state the program is compiled, then the mechanical behavior of damper is simulated and the hysteretic curve is obtained. Based on the above, a linear restoring model for SMA re-centring damper is put forward. And then, the program based on the theory of story model for shear tape is compiled to conduct elasto-plastic time history analysis of practical structure examples, According to the results, the seismic response of structure is significantly reduced, and the fully re-centring capacity after earthquake is obtained by this isolation system.

Hysteresis Loops of Base Isolation System - An Overview

2021 ◽  
Vol 879 ◽  
pp. 189-201
Author(s):  
M.A. Amir ◽  
N.H. Hamid
Keyword(s):  
Earthquake Engineering ◽  
Structural Damage ◽  
Base Isolation ◽  
Numerical Models ◽  
Hysteresis Loops ◽  
Human Beings ◽  
Rc Buildings ◽  
Isolation System ◽  
Base Isolation System ◽  
Isolation Systems

Recently, there are a lot of technological developments in the earthquake engineering field to reduce structural damage and one of them is a base isolation system. The base isolation system is one of the best technologies for the safety of human beings and properties under earthquake excitations. The aim of this paper is to review previous research works on simulation of base isolation systems for RC buildings and their efficiency in the safety of these buildings. Base isolation decouples superstructure from substructure to avoid transmission of seismic energy to the superstructure of RC buildings. The most effective way to assess the base isolation system for RC building under different earthquake excitations is by conducting experiment work that consumes more time and money. Many researchers had studied the behavior of base isolation system for structure through modeling the behavior of the base isolation in which base isolator is modeled through numerical models and validated through experimental works. Previous researches on the modeling of base isolation systems of structures had shown similar outcomes as the experimental work. These studies indicate that base isolation is an effective technology in immunization of structures against earthquakes.

Application of Semi-Active Oil Damper System to Base Isolation Systems

2002 ◽  
Author(s):  
Takashi Kawai ◽  
Yasuo Tsuyuki ◽  
Yutaka Inoue ◽  
Osamu Takahashi ◽  
Koji Oka
Keyword(s):  
Base Isolation ◽  
Shaking Table ◽  
The Other ◽  
Damping Coefficient ◽  
Damping Force ◽  
Mass Model ◽  
Maximum Acceleration ◽  
Rubber Bearing ◽  
Single Mass ◽  
Isolation Systems

This paper deals with one of the applications of the Semi-Active Oil Damper system, which applies base isolation systems reducing the maximum acceleration. The theory of the Semi-Active Oil Damper system is based on Karnopp Theory. The theory has been actually now in use for a Semi-active suspension system of the latest Shinkansen (New trunk lines) trains to improve passenger’s comfortable riding. Various experiments have been conducted using a single mass model whose weight is 15 ton on the shaking table. This model is supported by the rubber bearing. The natural frequency is 0.33Hz of this system. Two Semi-Active Oil Damper were installed in the model and excited the table for one horizontal direction. The maximum damping force of each Semi-Active Oil Damper used for the model is 4.21 kN. The damper can change the damping coefficient by utilizing two solenoid valves. Therefore, the dynamic characteristic of the damping force has two modes. One is a hard damping coefficient and the other is a soft one. It was confirmed that the maximum acceleration of the Semi-Active Oil Damper system can be reduced more than 20% in comparison with the passive Oil Damper system in our tests.

scholarly journals Pengaruh Penggunaan Base Isolation High Damping Rubber Bearing Pada Struktur Beton Bertulang

2020 ◽  
Vol 6 (2) ◽  
pp. 181-194
Author(s):  
Syahnandito ◽  
Reni Suryanita ◽  
Ridwan
Keyword(s):  
Base Isolation ◽  
Isolation System ◽  
Rubber Bearing ◽  
High Damping Rubber Bearing ◽  
Base Isolator ◽  
Base Isolation System ◽  
High Damping Rubber

Salah satu cara yang dapat dilakukan adalah menggunakan peredam beban gempa dengan sistem isolasi dasar (base isolation system). Penggunaan base isolation system  pada bangunan dapat mengisolasi perambatan getaran akibat gempa dari tanah ke struktur atas bangunan menggunakan komponen berbahan karet. Tujuan penelitian ini adalah untuk menganalisis pengaruh penggunaan sistem isolasi dasar berupa High Damping Rubber Bearing pada periode dan gaya geser dasar  struktur beton bertulang. Objek penelitian adalah bangunan hotel 15 lantai dengan ketinggian 62,9 m. Penelitian diawali dengan pemodelan struktur menggunakan aplikasi ETABS v2016 sehingga didapatkan periode dan gaya geser dasar struktur fixbase. Tahap selanjutnya memberikan gaya pada model struktur dengan isolasi dasar High Dumper Rubber Bearing sehingga didapatkan periode dan gaya geser dasar struktur dengan base isolator. Hasil analisis pada struktur fixbase didapatkan periode sebesar 4,212 detik, dengan gaya geser dasar didapatkan sebesar 1470,725 ton. Sedangkan hasil analisis pada struktur dengan base isolator didapatkan periode sebesar 5,500 detik, dengan gaya geser dasar didapatkan sebesar 1286,071 ton. Maka dapat disimpulkan bahwa pada struktur dengan base isolator terjadi peningkatan periode sebesar 30,58 %, sedangkan gaya geser dasar terjadi penurunan 12,56 %.

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