Proposal for an Efficient Damping System for High-Rise Buildings in Major Earthquakes

2016 ◽  
Vol 11 (1) ◽  
pp. 106-117
Author(s):  
Katsuhide Murakami ◽  
◽  
Masato Ishii ◽  
Kentaroh Miyazaki ◽  
Yasuhiro Tsuneki
Keyword(s):  
Vibration Control ◽  
Protection Mechanism ◽  
High Rise ◽  
Aspect Ratios ◽  
Individual System ◽  
Combined Use ◽  
New Type ◽  
Viscous Mass ◽  
Shearing Deformation ◽  
Damping Effects

Recent vibration resistant designs for buildings in Japan often adopt a vibration control structure with dampers arranged in the framework. Generally, the dampers are arranged in the building’s core in a geometry that works most effectively to protect against story shearing deformation. It is already known, however, that the above-mentioned arrangement of dampers does not provide good damping effects for the upper stories of high-rise buildings with large aspect ratios, because the protection mechanism is designed to decrease the shearing deformation components of the building’s horizontal deformation caused by its horizontal loads. A new type of dampers, called force-restricted tuned viscous mass dampers (FRTVMD), has been recently developed for such circumstances, amplifying the deformation of viscous dampers with their tuned mass effects. This paper, therefore, first presents a tuned mass damper (TMD) system, effective for high-rise buildings with large aspect ratios against great earthquakes, and then proposes a new vibration control structural system capable of generating better damping effects with FRTVMD. In addition, we review its characteristics and effects by analyzing its vibration response, as well as verify that a combined use of such vibration control structural systems will generate far greater damping effects than an individual system.

Combined Use of Enterocystoplasty and a New Type of Artificial Sphincter in the Treatment of Urinary Incontinence

1996 ◽  
Vol 156 (2S) ◽  
pp. 622-624 ◽  
Author(s):  
Salvador Vilar C. Lima ◽  
Luiz Alberto P. Araujo ◽  
Fabio O. Vilar ◽  
Carmen L. Kummer ◽  
Eduardo C. Lima
Keyword(s):  
Urinary Incontinence ◽  
Artificial Sphincter ◽  
Combined Use ◽  
New Type

scholarly journals Wind-Induced Vibration Control of High-Rise Structures Using Compound Damping Cables

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Jianda Yu ◽  
Zhibo Duan ◽  
Xiangqi Zhang ◽  
Jian Peng
Keyword(s):  
Vibration Control ◽  
Damping Ratio ◽  
Viscosity Coefficient ◽  
Structural Vibration ◽  
Vibration Displacement ◽  
High Rise ◽  
Main Cable ◽  
Small Vortex ◽  
Wind Induced Vibration ◽  
Fluctuating Wind

Based on the vibration reduction mechanism of compound damping cables, this study focuses on the wind-induced vibration control of high-rise structures with additional mass at the top. The differential equation of motion of the system under the action of the composite damping cable is established, and the analytical solution of the additional damping ratio of the structure is deduced, which is verified by model tests. The vibration response of the structure under the action of simple harmonic vortex excitation and randomly fluctuating wind loads is studied, and the effect of different viscous coefficients of the dampers in the composite damping cable and different installation heights of the damping cable on the vibration control is analyzed. The results show that a small vortex excitation force will cause large vibrations of low-dampened towering structures, and the structure will undergo buffeting under the action of wind load pulse force. The damping cable can greatly reduce the amplitude of structural vibration. The root means square of structural vibration displacement varies with damping. The viscosity coefficient of the device and the installation height of the main cable of the damping cable are greatly reduced.

scholarly journals Impact of Gust and Tectonic Drags on Irregular High Rise Structures

2020 ◽  
Vol 9 (9) ◽  
pp. 427-439
Keyword(s):  
Urban Infrastructure ◽  
High Rise ◽  
Aspect Ratios ◽  
Irregular Structures ◽  
Dynamic Forces ◽  
Gust Loads ◽  
Irregular Buildings ◽  
Structural Failures ◽  
The Impact ◽  
Base Width

As the population is growing and land becomes limited and new materials and construction technologies are built together, structural structures of this nature are growing larger and smaller, which are prone to two types of dynamic forces, tectonic drags and wind powers. In developing countries like India the exponential growth of the urban population has prompted a reassessment of the value of high – rise irregular buildings. For the construction of high - rise irregular buildings, the impact of gust loads is to be remembered. In India, gust caused numerous structural failures. IS 875:2015 Part-3 considers the gust loads on various kinds of irregular structures and IS 1893 (Part-1):2016 recognizes tectonic drags. The study focuses on peculiar constructions of different aspect ratios i.e. the impact of tears and tectonic drags. H / B ratio, with H being the overall construction system height; and B being the base width of the structure frame using STADD , Structure mass irregularities using E-TABS; from this paper we are examining the impact of wind (gusts), seismic (tectonical) load on building height by changing the number of floors with a the aspect rate. H / B ratio Many researchers design a system that is immune to tectonic drags, but the tectonic drag framework can not be built without causing damage. A large proportion of existing urban infrastructure is composed of vertical irregular structures.

scholarly journals Parameters and design optimization of the ring piezoelectric ceramic transformer

2015 ◽  
Vol 05 (03) ◽  
pp. 1550022 ◽  
Author(s):  
Jiří Erhart
Keyword(s):  
High Efficiency ◽  
Strong Electric Field ◽  
Resistive Load ◽  
Optimum Load ◽  
Aspect Ratios ◽  
Transformation Ratio ◽  
Ring Segment ◽  
New Type ◽  
Transformation Parameters ◽  
Piezoelectric Ceramic Transformer

Main aim of the presented paper is the theoretical analysis and experimental verification of the transformation parameters for the new type of nonhomogeneously poled ring transformer. The input part is poled in the thickness direction and output part in the radial direction. Two transformer geometries are studied — the input part is at inner ring segment, or it is at the outer ring segment. The optimum electrode size aspect ratios have been found experimentally as [Formula: see text] for the ring with aspect ratio [Formula: see text]. The fundamental as well as higher overtone resonances were studied for the transformation ratio, the optimum resistive load, efficiency and no-load transformation ratio. Higher overtones have better transformation parameters compared to the fundamental resonance. The new type ring transformer exhibits very high transformation ratios up to 200 under no-load and up to 13.4 under a high efficiency of 97% at the optimum load conditions of 10 [Formula: see text]. Strong electric field gradient at the output circuit is applicable for the electrical discharge generation.

Research on a New Type of Energy Dissipation Brace

2011 ◽  
Vol 71-78 ◽  
pp. 3816-3820
Author(s):  
Jie Yjing Sui ◽  
Wen Feng Liu
Keyword(s):  
Energy Dissipation ◽  
Dynamic Response ◽  
Vibration Control ◽  
Dynamic Behavior ◽  
Control Test ◽  
Magnification Factor ◽  
New Type ◽  
Energy Dissipation Devices

This paper presents one new configuration called little-character-toggle-brace. This paper analyses the effect of different toggle-brace position in the story and different angle of the toggle-brace to the magnification factor and provides the damping radio of the structure. Based on vibration control test of the structure with energy dissipation devices, the dynamic behavior and dynamic response of the structure with little-character brace, diagonal brace or little-character- toggle-brace have been investigated. The different control effects of the structure with the different energy dissipation braces have been studied. The result demonstrates that the little-character-toggle- brace is the best energy dissipation brace.

Shake Table Test of Complex High-Rise Building Equipped with Torsional Vibration Control Device

2012 ◽  
Vol 446-449 ◽  
pp. 3889-3893
Author(s):  
Bin Zhao ◽  
Juan He ◽  
Hui Gao ◽  
Xu Gang Chen
Keyword(s):  
Vibration Control ◽  
Torsional Vibration ◽  
Shake Table Test ◽  
Scale Model ◽  
Shake Table ◽  
Test Results ◽  
Torsional Mode ◽  
High Rise ◽  
High Rise Building ◽  
Local Space

For many high-rising buildings, large local space is very useful for its special function needs, such as conference hall and hotel lobby. The shake table test results of a high-rising building with large local space show that the dynamic characteristics of such structure are complex and the torsional mode becomes the first mode, while the torsional responses under earthquake excitation, especially of the floor just above the large local space, are very remarkable. In this paper, the bidirectional Tuned Mass Damper (TMD) is employed for reducing the torsional vibration of such complex high-rise building structure. A reduced-scale model is design and constructed. A series of shake table tests are carried out and the test results indicate that the TMD system is very effective in torsional vibration control of structural system.

Sign in / Sign up

Export Citation Format

Share Document