EFFECT OF VERTICAL STIFFNESS AND FOUNDATION UPLIFT ON THE SEISMIC RESPONSE OF BUILDING STRUCTURES

In recent decades, the application of semi-active control strategies has gained much attention as a way to reduce the seismic response of civil infrastructures. However, uncertainty in the modeling process of systems with possible partial or total failure during an earthquake is the main concern of engineers about the reliability of this strategy. In this regard, adaptive control algorithms are known as an effective solution to adjust control parameters with different uncertainties. In the current study, the efficiency of the simple adaptive control method (SACM) is investigated to control the seismic response of building structures in the presence of unknown structural damage and fault in the sensors. The method is evaluated in 20-story steel moment resisting frames with different arrangement of smart dampers and sensors with various damage and fault scenarios. The results show that the SACM control system can effectively reduce the maximum inter-story drift of the structure in all different assumed magnetorheological damper arrangements. Furthermore, combination of a Kalman–Bucy filter with the SACM improves robustness of the controller to the uncertainties of sensors faults and damages of structural elements.

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Effects of Vertical Stiffness of Rubber Bearings on the Vertical Seismic Response of Isolated High-rise Building

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/218/1/012001 ◽

2019 ◽

Vol 218 ◽

pp. 012001

Author(s):

Lei Zhang ◽

Zhengfei Chang ◽

Xingjie Zhang ◽

Gang Wang

Keyword(s):

Seismic Response ◽

Vertical Stiffness ◽

High Rise ◽

High Rise Building ◽

Rubber Bearings

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Seismic Response Control for Four High-Rise Building Structures Using Connected Control Method

Volume 1: 21st Biennial Conference on Mechanical Vibration and Noise, Parts A, B, and C ◽

10.1115/detc2007-35180 ◽

2007 ◽

Author(s):

Kazuto Seto ◽

Chinori Iio ◽

Shigeru Inaba ◽

Shingo Mitani ◽

Fadi Dohnal ◽

...

Keyword(s):

Seismic Response ◽

Active Control ◽

Control Method ◽

Control Force ◽

Building Structures ◽

Response Control ◽

Control Approach ◽

Seismic Response Control ◽

High Rise ◽

Lq Control

This paper presents a vibration control method for multiple high-rise buildings against large earthquake motion. This method is called as “Connected Control Method (CCM)” and has the merit of obtaining enough control force to protect high-rise buildings from large earthquakes using passive and semiactive devices. In this paper, first a modeling approach for four scaled building structures is shown and effectiveness of the CCM using LQ control approach for them is demonstrated by seismic response control results. Next, in order to reduce the supplied power, a semi-active control approach in place of active control is applied for the CCM. For this purpose, a new MR damper is developed and designed to have a close performance with results of the LQ control. This performance is verified by measured frequency responses.

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Seismic Response Analysis of Multi-Story Steel Frames Using BRB and SCB Hybrid Bracing System

Applied Sciences ◽

10.3390/app10010284 ◽

2019 ◽

Vol 10 (1) ◽

pp. 284 ◽

Cited By ~ 3

Author(s):

Rong Chen ◽

Canxing Qiu ◽

Dongxue Hao

Keyword(s):

Seismic Response ◽

Seismic Analysis ◽

Steel Frames ◽

Residual Deformation ◽

High Energy ◽

Response Analysis ◽

Building Structures ◽

Seismic Capacity ◽

Story Drift ◽

Bracing System

Multi-story steel frames are popular building structures. For those with insufficient seismic resistance, their seismic capacity can be improved by installing buckling-restrained braces (BRBs), which is known for high energy dissipation capacity, and the corresponding frame is denoted as BRB frame (BRBF). However, BRBFs are frequently criticized because of excessive residual deformations after earthquakes, which impede the post-event repairing work and immediate occupancy. Meanwhile, self-centering braces (SCBs), which were invented with a particular purpose of eliminating residual deformation for the protected structures, underwent fast development in recent years. However, the damping capability of SCBs is relatively small because their hysteresis is characterized by a flag shape. Therefore, this paper aims to combine these two different braces to form a hybrid bracing system. A total of four combinations are proposed to seek an optimal solution. The multi-story steel frames installed with BRBs, SCBs, and combined braces are numerically investigated through nonlinear static and dynamic analyses. Interested seismic response parameters refer to the maximum story drift ratios, maximum floor accelerations, and residual story drift ratios. The seismic analysis results indicate that the frames using the combined bracing system are able to take the advantages of BRBs and SCBs.

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