Energy Dissipation Capacity of Friction-Type Reinforcing Members Installed at a Transmission Tower

2008 ◽  
Author(s):  
Ji-Hun Park ◽  
Byoung-Wook Moon ◽  
Sung-Kyung Lee ◽  
Kyung-Won Min
Keyword(s):  
Energy Dissipation ◽  
Local Deformation ◽  
Test Results ◽  
Transmission Tower ◽  
Transmission Towers ◽  
Tower Structure ◽  
Loading Tests ◽  
Energy Dissipation Capacity ◽  
Reliable Design ◽  
Cyclic Loading Tests

Friction-type reinforcing members (FRMs) developed for the purpose of enhancing the wind-resistant performance of transmission towers are tested experimentally. The FRMs, in the middle of which slotted bolted connections (SBCs) are installed, are placed on the outside of tower legs, and provide additional damping and stiffness to the tower structure under bending deformations. Firstly, the SBCs used in the FRMs are tested for various frictional sliding interface conditions. Secondly, the FRMs are installed on a 1/2 scale plane tower substructure and cyclic loading tests are conducted. Energy dissipation capacity and effects from local deformations of the FRMs and joint slips are investigated. From the test results, remarkable energy dissipation capacity, reaching to the 2.4 times of that before the installation of the FRMs, is observed. However, the local deformation of the SBC and joint slip should be prevented for more reliable design of the FRMs.

Experimental Research on Seismic Behaviors of T-Shaped Concrete-Filled Steel Tubular Frame Joints

2011 ◽  
Vol 368-373 ◽  
pp. 38-41 ◽  
Author(s):  
Cheng Xiang Xu ◽  
Zan Jun Wu ◽  
Lei Zeng
Keyword(s):  
Energy Dissipation ◽  
Axial Compression ◽  
Design Principle ◽  
Hysteretic Behavior ◽  
Loading Tests ◽  
Energy Dissipation Capacity ◽  
Concrete Joints ◽  
Cyclic Loading Tests ◽  
Seismic Behaviors ◽  
Better Than

To understand mechanical characteristics and seismic behaviors of T-shaped concrete-filled steel tubular (CFST) joints, cyclic loading tests were carried out on four 1/2-scale exterior joints of top floor. The study includes joints’ mechanical character, failure mode, hysteretic behavior, ductility, energy dissipation and stiffness degradation under different height of beam and different axial compression ratios. The results indicate that frame joints satisfy the design principle of stronger joints and weaker components. The hysteretic loops are plump, ductility and energy dissipation capacity is better than that of ordinary reinforced concrete joints. Axial compression ratios can influence seismic behaviors of frame joints to some degree.

Experimental Research on the Influence of the Pile Type and Stirrup on the Seismic Performance of PHC Piles

2012 ◽  
Vol 256-259 ◽  
pp. 2079-2084 ◽  
Author(s):  
Tie Cheng Wang ◽  
An Gao ◽  
Hai Long Zhao
Keyword(s):  
Energy Dissipation ◽  
Cyclic Loading ◽  
Seismic Performance ◽  
High Strength Concrete ◽  
High Strength ◽  
Loading Tests ◽  
Energy Dissipation Capacity ◽  
Pile Type ◽  
Cyclic Loading Tests ◽  
Reversed Cyclic

The influence of the pile type and the stirrup on the seismic performance was evaluated based on the results of reversed cyclic loading tests on the four prestressed high strength concrete (PHC) piles. It is indicated that the AB-type pile has the better seismic performance than the A-type pile from the results. The bearing capacity does not increase obviously with decreasing of the stirrup spacing and increasing of the stirrup diameter. The degradation of stiffness does not decrease significantly with decreasing of the stirrup spacing and increasing of the stirrup diameter. The energy dissipation capacity is improved with increasing of the stirrup diameter and decreasing of the stirrup spacing.

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.

scholarly journals Low-Cyclic Loading Tests of Self-Centering Variable Friction (SCVF) Brace

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Qingguang He ◽  
Yanxia Bai ◽  
Weike Wu ◽  
Yongfeng Du
Keyword(s):  
Finite Element ◽  
Friction Coefficient ◽  
Energy Dissipation ◽  
Cyclic Loading ◽  
Variable Friction ◽  
Loading Tests ◽  
Low Cyclic Loading ◽  
Energy Dissipation System ◽  
Cyclic Loading Tests ◽  
Dissipation System

A novel assembled self-centering variable friction (SCVF) brace is proposed which is composed of an energy dissipation system, a self-centering system, and a set of force transmission devices. The hysteretic characteristics and energy dissipation of the SCVF brace with various parameters from low-cyclic loading tests are presented. A finite element model was constructed and tested under simulated examination for comparative analysis. The results indicate that the brace shows an atypical flag-type hysteresis curve. The SCVF brace showed its stable self-centering ability and dissipation energy capacity within the permitted axial deformation under different spring and friction plates. A larger deflection of the friction plate will make the variable friction of this SCVF brace more obvious. A higher friction coefficient will make the energy dissipation capacity of the SCVF brace stronger, but the actual friction coefficient will be lower than the design value after repeated cycles. The results of the fatigue tests showed that the energy dissipation system formed by the ceramic fiber friction blocks and the friction steel plates in the SCVF brace has a certain stability. The finite element simulation results are essentially consistent with the obtained test results, which is conducive to the use of finite element software for calculation and structural analysis in actual engineering design.

Seismic Rehabilitation of Beam-Column Joints Using FRP Sheets and Buckling Restrained Braces

2013 ◽  
Vol 479-480 ◽  
pp. 1170-1174
Author(s):  
Hee Cheul Kim ◽  
Dae Jin Kim ◽  
Min Sook Kim ◽  
Young Hak Lee
Keyword(s):  
Shear Strength ◽  
Reinforced Concrete ◽  
Energy Dissipation ◽  
Seismic Performance ◽  
Reinforced Concrete Structures ◽  
Test Results ◽  
Seismic Rehabilitation ◽  
Buckling Restrained Braces ◽  
Column Joint ◽  
Energy Dissipation Capacity

The purpose of this study was to evaluate seismic performance of rehabilitated beam-column joint using FRP sheets and Buckling Restrained Braces (BRBs) and provide test data related to rehabilitated beam-column joints in reinforced concrete structures. The seismic performance of total six beam-column specimens is evaluated under cyclic loadings in terms of shear strength, effective stiffness, energy dissipation and ductility. The test results showed wrapping FRP sheets can contribute to increase the effect of confinement and the crack delay. Also retrofitting buckling restrained braces (BRBs) can improve the stiffness and energy dissipation capacity. Both FRP sheets and BRBs can effectively improve the strength, stiffness and ductility of seismically deficient beam-column joints.

Experimental Investigations on the Seismic Behavior of Precast Concrete Columns with Novel Box Connections

2019 ◽  
Vol 14 (02) ◽  
pp. 2050007
Author(s):  
Xizhi Zhang ◽  
Shengbo Xu ◽  
Shaohua Zhang ◽  
Gaodong Xu
Keyword(s):  
Energy Dissipation ◽  
Bearing Capacity ◽  
Failure Mode ◽  
Seismic Behavior ◽  
Load Transfer ◽  
Precast Concrete ◽  
Hysteretic Behavior ◽  
Experimental Investigations ◽  
Test Results ◽  
Energy Dissipation Capacity

In this study, two types of novel box connections were developed to connect precast concrete (PC) columns and to ensure load transfer integrity. Cyclic loading tests were conducted to investigate the seismic behavior of the PC columns with proposed connections as well as the feasibility and reliability of novel box connections. The failure mode, hysteretic behavior, bearing capacity, ductility, stiffness degradation and energy dissipation were obtained and discussed. The test results indicated that the all PC columns exhibited the ductile flexural failure mode and that the proposed connections could transfer the force effectively. The adoption of novel box connections could improve the deformation capacity and energy dissipation capacity of PC columns. A higher axial compression ratio could enhance the bearing capacity of PC column with proposed connection but would significantly deteriorate the ductility and energy dissipation capacity. Finite element models were developed and the feasibility of the models was verified by the comparison with the test results.

scholarly journals Experimental Study on the Seismic Performance of a Partition Damped Wall-Filled Frame Structure

2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Shuainan Zhai ◽  
Zuyin Zou ◽  
Zhanyuan Zhu ◽  
Zixing Zhang ◽  
Wei Liang ◽  
...  
Keyword(s):  
Failure Modes ◽  
Lateral Displacement ◽  
Steel Frame ◽  
Frame Structure ◽  
Comparison Analysis ◽  
Significant Damage ◽  
Loading Tests ◽  
Energy Dissipation Capacity ◽  
Mechanical Performances ◽  
Cyclic Loading Tests

In the past, earthquakes have caused significant damage to traditional masonry filler wall frame structures. To solve this problem, a new design scheme, the partition damping filler wall, is proposed in this paper to reduce the interaction between the filler wall and the frame structure. Low cyclic loading tests are carried out on the traditional and the new masonry filler wall frames. Besides, one full-scale-angled span layer frame without a filler wall is produced for comparison analysis. The mechanical performances of the different frames are studied, including the characteristics of the deformation failure modes, hysteretic curves, skeleton curves, rigidity degeneration, energy dissipation capacity, and the lateral displacement of the frame columns. The research results show that the partition damping filler wall can significantly decrease the diagonal bracing effect of the filler wall on the steel frame. Meanwhile, the setting of the low-strength mortar between the filler wall and steel frame and the arrangement of the damping layer can improve the stress distribution and delay the crack development of the wall. Furthermore, the stiffness degradation rate of the partition damping filler wall is obviously slower than that of the traditional masonry filler wall frame structure. In this paper, the partition damped wall-filled frame structure shows outstanding ductility and deformation capacity.

scholarly journals Effect of column foot tenon on behavior of larch column base joints based on concrete plinth

BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 6648-6667
Author(s):  
Xiaoli Han ◽  
Jian Dai ◽  
Wei Qian ◽  
Baolong Li ◽  
Yuanjun Jin ◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Hysteretic Behavior ◽  
Timber Structures ◽  
Test Results ◽  
Rotational Angle ◽  
Static Test ◽  
Energy Dissipation Capacity ◽  
The Moment ◽  
Reversed Cyclic ◽  
Column Base

The wooden columns in timber structures of ancient buildings have column foot tenons of various sizes. The main reason for these differences is their use for different roof loads. Six full-scale specimens with different sizes of column foot tenon were designed and manufactured. The tree species used for the specimens was larch. The quasi-static test was conducted on the specimens that were used in timber structures of ancient buildings. The effects of column foot tenon size on the mechanical properties of larch wooden columns were studied. The moment-rotational angle hysteretic curves, moment-rotational angle skeleton curves, ductility, stiffness degradation, energy dissipation capacity, slippages between the wooden column and the plinth, and the damage of the column foot tenons were examined. The test results showed that the column foot tenon played an important role in the mechanical behavior of the wooden column under low-cycle reversed cyclic loading. The rotation of the column foot tenon improved the energy dissipation capacity of the wooden column. As the rotational angle of the column base increased, the column foot tenon had different degrees of damage. Different sizes of column foot tenon had their own advantages and hysteretic behavior.

scholarly journals Experimental and Theoretical Investigations of a Displacement-Amplified Torsional Damper

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Huimin Mao ◽  
Xueyuan Yan ◽  
Xiangliang Ning ◽  
Shen Shi
Keyword(s):  
Energy Dissipation ◽  
Frame Structure ◽  
Seismic Capacity ◽  
Strong Earthquakes ◽  
Theoretical Investigations ◽  
Good Energy ◽  
Loading Tests ◽  
High Damping Rubber ◽  
Cyclic Loading Tests ◽  
Theoretical Analyses

In this work, a displacement-amplified torsional damper (DATD) is proposed for improving the seismic capacity of the beam-column joints of a frame structure. The proposed DATD uses common steel, lead, and high-damping rubber. This damper exhibits good energy dissipation under small earthquakes. Under strong earthquakes and large displacements, the strengthening of the high-damping rubber can improve the overall stiffness of the damper and increase the energy dissipation. In order to investigate the performance of the proposed DATD, theoretical analyses, simulations, and cyclic loading tests were performed, and their results were compared, showing an overall good agreement.

scholarly journals Assessment of material strain limits for defining plastic regions in concrete structures

2009 ◽  
Vol 42 (2) ◽  
pp. 86-95 ◽  
Author(s):  
Adam F. Walker ◽  
Rajesh P. Dhakal
Keyword(s):  
New Zealand ◽  
Concrete Structures ◽  
Local Deformation ◽  
Plastic Hinges ◽  
New Approach ◽  
Ductility Factor ◽  
Loading Tests ◽  
Cyclic Loading Tests ◽  
Beam Height ◽  
Reversed Cyclic

The New Zealand Structural Loadings Standard, until its latest revision, used the structural ductility factor as a measure of the deformation demand of all potential plastic hinges in a structure. In the new version of New Zealand Standard for Earthquake Actions (NZS 1170.5:2004) the detailing of potential plastic regions is determined according to the local deformation demand in these regions. The change has been prompted by evidence that the structural ductility factor gives a poor indication of the demand on individual plastic regions. This new approach has also been adopted by the revised New Zealand Concrete Structures Standard (NZS 3101:2006) which classifies potential plastic regions into three categories (namely ductile, limited ductile and nominally ductile) based upon their inelastic deformation demand specified in terms of material strain limits. The material strain limits currently set in NZS 3101:2006 for the three categories of plastic regions are based on limited experimental evidence and need a closer revision. This paper tries to obtain more justifiable values of material strain limits based on experimental data. In this research, reversed cyclic loading tests of beams are conducted to compensate for a lack of data in the nominally ductile range of detailing. Based on the results of the tests conducted, curvature limits for nominally ductile plastic hinges are derived. Combining the experimental results collected from literature and the tests conducted in this project, updated material strain limits for the three categories of plastic regions are proposed. To unify the design process for all types of plastic regions, curvature limits for nominally ductile plastic hinges are also proposed as the multiple of first yield curvature (similar to the existing approach for the other two categories of plastic regions) rather than the existing approach of specifying allowable compressive (concrete) and tensile (rebar) strain limits for nominally ductile plastic regions. To further simplify the process, the representative value of first yield curvature is approximated as two times the yielding strain to the beam height ratio, thereby relieving the designers from having to conduct section analysis to estimate neutral axis depth.

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