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 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.

Estimation of Seismic Energy Dissipation for Steel Slit Shear Walls Considering Out-of-Plane Buckling

2021 ◽  
Author(s):  
Yiming Ma ◽  
Liusheng He ◽  
Ming Li
Keyword(s):  
Energy Dissipation ◽  
Shear Walls ◽  
Seismic Energy ◽  
Thickness Ratio ◽  
Design Parameters ◽  
Test Results ◽  
Loading Test ◽  
Aspect Ratios ◽  
Out Of Plane ◽  
Energy Dissipation Capacity

Steel slit shear walls (SSSWs), made by cutting slits in steel plates, are increasingly adopted in seismic design of buildings for energy dissipation. This paper estimates the seismic energy dissipation capacity of SSSWs considering out-of-plane buckling. In the experimental study, three SSSW specimens were designed with different width-thickness ratios and aspect ratios and tested under quasi-static cyclic loading. Test results showed that the width-thickness ratio of the links dominated the occurrence of out-of-plane buckling, which produced pinching in the hysteresis and thus reduced the energy dissipation capacity. Out-of-plane buckling occurred earlier for the links with a larger width-thickness ratio, and vice versa. Refined finite element model was built for the SSSW specimens, and validated by the test results. The concept of average pinching parameter was proposed to quantify the degree of pinching in the hysteresis. Through the parametric analysis, an equation was derived to estimate the average pinching parameter of the SSSWs with different design parameters. A new method for estimating the energy dissipation of the SSSWs considering out-of-plane buckling was proposed, by which the predicted energy dissipation agreed well with the test results.

Experimental Test of Welded Wide Flange Fuses

2018 ◽  
Vol 763 ◽  
pp. 414-422 ◽  
Author(s):  
Tony Y. Yang ◽  
Winda Banjuradja ◽  
Lisa Tobber
Keyword(s):  
Energy Dissipation ◽  
Longitudinal Direction ◽  
Elastic Stiffness ◽  
Design Parameters ◽  
Structural Components ◽  
Earthquake Energy ◽  
Aspect Ratios ◽  
Metallic Dampers ◽  
Energy Dissipation Capacity ◽  
Metallic Damper

Metallic dampers are one of the most prevalent structural components that are used to dissipate earthquake energy. A novel metallic damper, named Welded Wide Flange Fuse (WWFF), is proposed in this paper. WWFF utilizes commonly available welded wide flange sections to dissipate the earthquake energy through shear yielding of the web in the longitudinal direction, which makes the WWFF easy to be fabricated and efficient in providing high elastic stiffness and stable energy dissipation capacity. In this paper, a detailed experimental study was conducted to examine the influence on the design parameters (such as aspect ratios and slenderness ratios) on the component response (such as yielding force and elastic stiffness). The result shows that the WWFF has stable energy dissipation capacity which can be used as an efficient and robust metallic damper.

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.

EXPERIMENTAL STUDY AND APPLICATION OF METALLIC YIELDING–FRICTION DAMPER

2013 ◽  
Vol 07 (03) ◽  
pp. 1350012 ◽  
Author(s):  
GANG LI ◽  
HONG-NAN LI
Keyword(s):  
Energy Dissipation ◽  
Design Method ◽  
Seismic Energy ◽  
Small Scale ◽  
Friction Damper ◽  
Friction Behavior ◽  
Static Test ◽  
Good Ability ◽  
Friction Component ◽  
Friction Plate

In this paper, a new idea for designing the metallic yielding–friction damper (MYFD) is presented based on the principle that the metallic plate can be used for yielding and can be the friction component of the passive energy dissipation device (PEDD). This type of damper is so-called the MYFD, because it consists of yielding part and friction part. Phased energy dissipation is realized throughout the metallic yielding plate and friction plate combination where friction behavior is prior to yielding behavior. The quasi-static test with two small-scale MYFDs is carried out. Then, it is applied in an actual reinforced concrete building. The design method and fitting process of the MYFDs are introduced. In order to compare seismic responses of the building with and without the dampers, a dynamic analysis of the building under earthquakes is performed. The results show that the MYFD presented here possess good ability of seismic energy dissipation.

Optimum Design of a New Hysteretic Dissipater

2013 ◽  
pp. 274-299
Author(s):  
Dora Foti ◽  
Riccardo Nobile
Keyword(s):  
Energy Dissipation ◽  
High Capacity ◽  
Hysteresis Loops ◽  
Seismic Energy ◽  
Dissipated Energy ◽  
Seismic Action ◽  
Finite Element Software ◽  
Out Of Plane ◽  
Optimization Routine ◽  
Structural Parts

In this chapter, a new seismic protection device is proposed. It is designed to dissipate the energy entering a structure subject to seismic action through the activation of hysteresis loops of the material that composes it. These devices are characterized by a high capacity to absorb the seismic energy and the ability to concentrate the damage on it and, consequently, to keep the structure and the structural parts undamaged. Moreover, after a seismic event they can be easily replaced. In particular, this chapter proposes a new shear device that shows the plasticity of some areas of the device at low load levels. In order to maximize the amount of dissipated energy, the design of the device was performed by requiring that the material be stressed in an almost uniform way. In particular, the device is designed to concentrate energy dissipation for plasticity in the aluminum core while the steel parts are responsible to make stiffer the device, limiting out-of-plane instability phenomena. The geometric configuration that maximizes the energy dissipation has been determined using a structural optimization routine of finite element software.

scholarly journals Metallic Slit-Plate Dampers: Damage Evaluation with Metal Magnetic Memory Technique and Application to Structures with Rocking Columns

Metals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 953 ◽  
Author(s):  
Chihab Abarkane ◽  
German Ríos-García ◽  
David Gale-Lamuela ◽  
Francisco Rescalvo ◽  
Antolino Gallego ◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Damage Index ◽  
Magnetic Memory ◽  
Metallic Materials ◽  
Concrete Frames ◽  
Metallic Dampers ◽  
Energy Dissipation Capacity ◽  
Metallic Slit ◽  
Cost Efficient ◽  
Metallic Damper

Inelastic deformation of metallic materials is one of the most effective mechanisms for the dissipation of energy input to a structure by an earthquake. Metallic dampers are special devices that resort to this source of energy dissipation, proving to be a cost-efficient solution for the seismic protection of structures. Two important issues arise when implementing metallic dampers in real structures: (1) Inelastic deformations cause damage that must be quantified after an earthquake to decide upon their eventual replacement; (2) dampers must possess an energy dissipation capacity large enough to endure severe earthquakes. This paper focuses on a particular type of metallic damper consisting of slit-plates made of stainless steel, applied to reinforced concrete frames with rocking columns at the first story. In particular, a new damage index based on the metallic magnetic memory (MMM) method is proposed and validated experimentally to quantify the damage of slit plate dampers subjected to cyclic loadings. Further, the seismic response of a frame with rocking columns that incorporate the damper is obtained to demonstrate that it can endure severe earthquakes without failing, and to emphasize the relevance of the proposed MMM damage index that would make its replacement after a severe earthquake unnecessary.

scholarly journals The Experimental Analysis Of An Innovative Yielding Metallic Damper

2015 ◽  
Vol 11 (2) ◽  
pp. 38-45 ◽  
Author(s):  
Vasile-Mircea Venghiac ◽  
Mihai Budescu
Keyword(s):  
Experimental Study ◽  
Energy Dissipation ◽  
Seismic Energy ◽  
Seismic Protection ◽  
Frame Structures ◽  
Shake Table ◽  
Natural Phenomena ◽  
Steel Frame Structures ◽  
Energy Dissipation Capacity ◽  
Metallic Damper

Abstract One of the most destructive natural phenomena is the earthquake. These events destroy lives, goods and disrupt human activities. For this reason the anti-seismic protection of buildings is a very important and of interest subject in Civil Engineering. In the case of structures with a low seismic energy dissipation capacity (for example steel frame structures with Slimdek composite floors), this problem becomes more complicated due to the requirement of dampers. In this paper an experimental study is presented regarding an innovative yielding metallic energy dissipation device, proposed by the author. An experiment is carried out on a shake table. By studying the results from the experiments and from the previous carried out numerical analysis we can conclude that this device provides a high anti-seismic protection for this type of structures.

scholarly journals Effects of mortar compressive strength on out of plane response of unreinforced masonry walls

2021 ◽  
Vol 20 (2) ◽  
pp. 371-381
Author(s):  
Atabak Pourmohammad Sorkhab ◽  
◽  
Mesut Küçük ◽  
Ali Sari ◽  
◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Unreinforced Masonry ◽  
Infill Wall ◽  
Infill Walls ◽  
Clay Bricks ◽  
Mortar Strength ◽  
Load Carrying ◽  
Out Of Plane ◽  
Structural Behaviors ◽  
Major Crack

In this study, the out-of-plane response of infill walls that are widely used in Turkey and the surrounding regions were experimentally investigated. Several out-of-plane wall tests were performed in the laboratory, with the walls specimens produced with lateral hollow clay bricks (LHCB) and different mortar qualities. The walls were tested in their out-of-plane (OOP) direction under static load conditions and evaluated based on the load-bearing and energy dissipation capacities, crack propagations, mortar strengths, and initial stiffnesses. These walls are experimentally investigated to understand the effects of the mortar strength on the infill wall structural behaviors and to assess the effectiveness of the out-of-plane strength formulations. It was found that when the mortar strength is low, the first major crack occurs at the mortar, however, because of the arch mechanism efficiency in this situation the OOP load-carrying and energy dissipation capacities of unreinforced walls can be significantly increased. When the first major crack in the wall occurs in the brick itself, the arc mechanism is provided with delicate sections in the brick, which leads to strength decreasing in the walls. In this case, excessive deviations occur in the out-of-plane strength formulations estimates. This study shows that the arc mechanism, the damage start region and progress can change significantly unreinforced masonry (URM) infill walls behaviors.

Sign in / Sign up

Export Citation Format

Share Document