NEW STRUCTURAL SYSTEM FOR EARTHQUAKE RESILIENT DESIGN

2013 ◽  
Vol 07 (03) ◽  
pp. 1350013 ◽  
Author(s):  
XILIN LU ◽  
YUANJUN MAO ◽  
YUN CHEN ◽  
JINGJING LIU ◽  
YING ZHOU
Keyword(s):  
Basic Function ◽  
Shaking Table ◽  
Original Position ◽  
Structural System ◽  
Coupling Beams ◽  
New Approach ◽  
Resilient Design ◽  
Rubber Bearings ◽  
Energy Dissipation Devices ◽  
Short Time

The concept of self-centering structure and replaceable structural member or fuse is a new approach of earthquake resilient structural design. The new structural system is not only capable of preventing from failure of the structure and life safety of the occupants during earthquakes, but also quickly restoring its basic function in a short time following earthquakes. Restoring the original position through self-weight or pre-stressing forces, this kind of structures is defined as a rocking or self-centering structure. The replaceable elements of the other new kind of structural system, which includes coupling beams, energy dissipation devices, and rubber bearings and so on, are designed to be inelastic or failure, like a fuse, and to protect the main structure from damage in the region of high seismicity. The authors of this paper will report three different tests on new earthquake resilient structures, which are shaking table tests on a self-centering RC frame, quasi-static cyclic tests on RC wall with replaceable coupling beams and the ones with replaceable foot parts. All of the three new kind structural systems present an efficient resilient ability under severe horizontal forces in the tests.

Sub-Structure Pseudo-Dynamic Response Test of a Pseudo-Elastic Bracing System Made of Shape Memory Alloy

2005 ◽  
Vol 297-300 ◽  
pp. 628-634 ◽  
Author(s):  
Kenichi Ohi ◽  
Jae Hyouk Choi
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Original Position ◽  
Small Displacement ◽  
Structural System ◽  
Dynamic Tests ◽  
System A ◽  
Hysteretic Damper ◽  
Bracing System ◽  
Fail Safe

This paper deals with shape memory alloy. As a first step to assess the applicability of this kind of alloy in a structural system, a tension bar made of this kind of alloy that exhibits pseudo-elasticity at room temperature is used herein as a passive bracing system. This paper describes sub-structure pseudo-dynamic tests on pseudo-elastic bracing system with hysteretic damper. A pseudo-elastic bracing system is better to be used with other hysteretic elements such as a hysteretic damper. A damper provides energy dissipation within small displacement levels, and a pseudo-elastic bracing system works in turn as a back-up/fail-safe system when an accidental failure of damper or damper interface occurs, and also it helps to pull back the structure to the original position by uninstalling the damper after earthquake.

scholarly journals Earthquake forecasting and its verification

2005 ◽  
Vol 12 (6) ◽  
pp. 965-977 ◽  
Author(s):  
J. R. Holliday ◽  
K. Z. Nanjo ◽  
K. F. Tiampo ◽  
J. B. Rundle ◽  
D. L. Turcotte
Keyword(s):  
Temporal Variations ◽  
Earthquake Forecasting ◽  
Earthquake Risk ◽  
Decision Threshold ◽  
New Approach ◽  
Pi Method ◽  
Time Prediction ◽  
Short Time ◽  
Large Earthquakes ◽  
Proven Method

Abstract. No proven method is currently available for the reliable short time prediction of earthquakes (minutes to months). However, it is possible to make probabilistic hazard assessments for earthquake risk. In this paper we discuss a new approach to earthquake forecasting based on a pattern informatics (PI) method which quantifies temporal variations in seismicity. The output, which is based on an association of small earthquakes with future large earthquakes, is a map of areas in a seismogenic region ("hotspots'') where earthquakes are forecast to occur in a future 10-year time span. This approach has been successfully applied to California, to Japan, and on a worldwide basis. Because a sharp decision threshold is used, these forecasts are binary--an earthquake is forecast either to occur or to not occur. The standard approach to the evaluation of a binary forecast is the use of the relative (or receiver) operating characteristic (ROC) diagram, which is a more restrictive test and less subject to bias than maximum likelihood tests. To test our PI method, we made two types of retrospective forecasts for California. The first is the PI method and the second is a relative intensity (RI) forecast based on the hypothesis that future large earthquakes will occur where most smaller earthquakes have occurred in the recent past. While both retrospective forecasts are for the ten year period 1 January 2000 to 31 December 2009, we performed an interim analysis 5 years into the forecast. The PI method out performs the RI method under most circumstances.

A Novel Approach to Nanoscale Materials Synthesis Using Industrial Laser Processing of Organosilazane Liquid Precursors

1990 ◽  
Vol 206 ◽  
Author(s):  
Tongsan D. Xiao ◽  
Peter R. Strutt ◽  
Kenneth E. Gonsalves
Keyword(s):  
Ceramic Powder ◽  
Average Diameter ◽  
Current Approach ◽  
Powder Materials ◽  
Materials Synthesis ◽  
Laser Plume ◽  
New Approach ◽  
Novel Approach ◽  
Liquid Precursors ◽  
Short Time

ABSTRACTA new approach has been developed for the synthesis of nanoscale ceramic powder materials from liquid organosilazane precursors. This technique, by exploiting fast kinetic chemical and physical reactions, makes it possible to synthesize significant quantities of material in a relatively short time. In the current approach aerosols of a silazane monomer, (CH3SiHNH)n, (n = 3 or 4), of mol. wt. 280–320, are injected into the beam of a cw industrial CO2 laser to obtain nanoscale ceramic powders. Injection of the aerosol into the laser-beam results in a high-temperature plume. Rapid condensation of the molecular precursor species emerging from the laser plume results in the formation of preceramic polymer particles, with an average diameter of 62 nm. One attractive feature of this process is that 70 wt.% of the liquid precursor is converted into nanoscale powders. Another feature is that only a further 10 wt.% loss occurs during post thermal treatment to form the end-product.

scholarly journals PENYULUHAN DEMAM BERDARAH DENGUE (DBD) KEPADA PELAJAR-PELAJAR DI PERGURUAN KRISTEN METHODIST-2 RANTAUPRAPAT

2021 ◽  
Vol 2 (1) ◽  
pp. 33-41
Author(s):  
Saharnauli Janna Verawaty Simorangkir
Keyword(s):  
Dengue Virus ◽  
Dengue Fever ◽  
Mosquito Vectors ◽  
Public Concern ◽  
New Approach ◽  
Dengue Disease ◽  
Agents Of Change ◽  
Agent Of Change ◽  
Short Time ◽  
Activity Method

Abstrak Penyakit demam berdarah merupakan salah satu masalah kesehatan di Kota Medan yang cenderung menimbulkan kekhawatiran masyarakat karena perjalanan penyakitnya cepat dan dapat menyebabkan kematian dalam waktu yang singkat. Penyakit demam berdarah adalah penyakit yang disebabkan oleh virus dengue. Virus ini ditularkan melalui vector nyamuk. Pendekatan pemberantasan demam berdarah yang berwawasan kepedulian masyarakat merupakan salah satu alternatif pendekatan baru dalam rangka pengendalian penyebaran penyakit ini. Tujuan dari kegiatan ini adalah untuk memberikan penjelasan kepada pelajar-pelajar yang diharapkan dapat menjadi agent of change di lingkungannya dalam pemberantasan penyakit DBD ini. Metode kegiatan ini dilaksanakan dalam bentuk penyuluah, tanya jawab dan games. Kegiatan ini dinilai cukup berhasil. Indikator keberhasilannya adalah berdasarkan antusiasme peserta untuk bertanya dan feedback dari peserta yang menyatakan penyuluhan ini dinilai menarik dan bermanfaat. Kesimpulan dari kegiatan ini adalah melalui keilmuan yang dimiliki dapat digunakan untuk membantu memberikan pemahaman mengenai penyakit-penyakit kepada masyarakat, yang pada akhirnya dapat mendorong partisipasi masyarakat dalam pencegahan penularan dan pertambahan kasus-kasus penyakit tertentu di masyarakat Abstract Dengue fever is one of the health problems in Medan City which tends to cause public concern because the disease progresses quickly and can cause death in a short time. Dengue fever is a disease caused by the dengue virus. This virus is transmitted by mosquito vectors. The approach to eradicating dengue fever with a public concern is an alternative to a new approach to control the spread of this disease. The purpose of this activity is to provide explanations to students who are expected to become agents of change in their environment in eradicating this dengue disease. This activity method was carried out in the form of counseling, question and answer and games. This activity was considered quite successful. The success indicator was based on the enthusiasm of the participants to asked questions and feedback from the participants who stated that this counseling was considered interesting and useful. The conclusion of this activity was that through the knowledge that is owned it can be used to help provide an understanding of diseases to the community, which in turn can encourage community participation in preventing the transmission of certain diseases in the community.

“The Death of Liberal Internationalism?: Donald Trump, Walmart, and the Two Koreas”

2018 ◽  
Vol 25 (2) ◽  
pp. 169-197
Author(s):  
Mitchell B. Lerner
Keyword(s):  
United States ◽  
The United States ◽  
Business Practices ◽  
Short Term ◽  
New Approach ◽  
Liberal Internationalism ◽  
The People ◽  
Modern Business ◽  
Short Time

The election of Donald J. Trump unsettled many areas of U.S. foreign policy, but few more than the nation’s relationship with Korea. This article argues that the Trump administration’s vision for the world represents a stark break from the tradition of liberal internationalism and instead seeks to take the United States down a path that reflects the modern business practices of giant American corporations. A suitable label for this vision, as the following pages will show, is “Walmart unilateralism.” This framework abandons the traditional American policies of nation building and alliances based on shared ideological values. Instead, it embraces a more short-term approach rooted in financial bottom lines, flexible alliances and rivalries, and the ruthless exploitation of power hierarchies. This new approach, this article concludes, may dramatically transform the American relationship with Korea. Walmart unilateralism in Korea almost certainly will have some short-time positive ramifications for the United States, but its larger failure to consider the history and values of the people living on the Korean Peninsula may generate serious long-term problems for the future experience of the United States in the region.

Usage of Comprehensive Learning Particle Swarm Optimization for Parameter Identification of Structural System

2015 ◽  
Vol 5 (2) ◽  
pp. 1-15 ◽  
Author(s):  
Hesheng Tang ◽  
Lijun Xie ◽  
Songtao Xue
Keyword(s):  
Particle Swarm Optimization ◽  
Particle Swarm ◽  
Shaking Table ◽  
Structural System ◽  
Swarm Optimization ◽  
New Strategy ◽  
Limited Output ◽  
Table Model ◽  
Swarm Intelligence Based Algorithm ◽  
Shear Building

This paper introduces a novel swarm intelligence based algorithm named comprehensive learning particle swarm optimization (CLPSO) to identify parameters of structural systems, which could be formulated as a multi-modal numerical optimization problem with high dimension. With the new strategy in this variant of particle swarm optimization (PSO), historical best information for all other particles is used to update a particle's velocity. This means that the particles have more exemplars to learn from, as well as have a larger potential space to fly, avoiding premature convergence. Simulation results for identifying the parameters of a five degree-of-freedom (DOF) structural system under conditions including limited output data, noise polluted signals, and no prior knowledge of mass, damping, or stiffness are presented to demonstrate improved estimation of these parameters by the CLPSO when compared with those obtained from standard PSO. In addition, the efficiency and applicability of the proposed method are experimentally examined by a twelve-story shear building shaking table model.

Shaking Table Tests of Full Scale Base-Isolated Structures

2002 ◽  
Author(s):  
C. S. Tsai ◽  
B. J. Chen ◽  
T. C. Chiang
Keyword(s):  
Structural Control ◽  
Control Strategies ◽  
Steel Structure ◽  
Seismic Energy ◽  
Full Scale ◽  
Shaking Table ◽  
Shaking Table Tests ◽  
Natural Period ◽  
Rubber Bearing ◽  
Rubber Bearings

Conventional earthquake resistant designs depend on strengthen and ductility of the structural components to resist induced forces and to dissipate seismic energy. However, this can produce permanent damage to the joints as well as the larger interstory displacements. In recently years, many studies on structural control strategies and devices have been developed and applied in U. S. A., Europe, Japan, and New Zealand. The rubber bearing belongs to one kind of the earthquake-proof ideas of structural control technologies. The installation of rubber bearings can lengthen the natural period of a building and simultaneously reduce the earthquake-induced energy trying to impart to the building. They can reduce the magnitude of the earthquake-induced forces and consequently reduce damage to the structures and its contents, and reduce danger to its occupants. This paper is aimed at studying the mechanical behavior of the stirrup rubber bearings (SRB) and evaluating the feasibility of the buildings equipped with the stirrup rubber bearings. Furthermore, uniaxial, biaxial, and triaxial shaking table tests are conducted to study the seismic response of a full-scale three-story isolated steel structure. Experimental results indicate that the stirrup rubber bearings possess higher damping ratios at higher strains, and that the stirrup rubber bearings provide good protection for structures. It has been proved through the full-scale tests on shaking table that the stirrup rubber bearing is a very promising tool to enhance the seismic resistibility of structures.

Shaking Table Tests of Critical Equipment With Simple Isolators

2006 ◽  
Author(s):  
C. S. Tsai ◽  
Wen-Shin Chen ◽  
Shih-Hsien Yu ◽  
Chen-Tsung Yang
Keyword(s):  
Shaking Table ◽  
Original Position ◽  
Economic Losses ◽  
High Tech ◽  
Shaking Table Tests ◽  
Restoring Force ◽  
Ground Acceleration ◽  
Maximum Displacement ◽  
Natural Period ◽  
Energy Absorbing

Because the earthquake is one kind of non-predictable calamity and happens suddenly, its disaster and consequence are larger than other calamities. Mankind must face not only the emotional effects caused by earthquakes, but also the damage to the structure and substructure systems. The fire, damaged pipeline systems cased by earthquake and the destruction of the semiconductor, equipment or microelectronics in high-tech factories will cause an enormous and a chain of economic losses. Therefore, there is a need of an economical and efficient method to protect equipments from earthquake damage. Namely, in addition to promoting the earthquake-resistant capacity of structures, it is also important to ensure the safety of the expensive equipment and facilities. In this study, it is aimed at developing a new simple isolator with appropriate damping for critical equipment. The basic principle of the simple isolator is to lengthen the natural period of equipment, and simultaneously to reduce the earthquake-induced energy and the displacement of the isolator by additional damping. A series of shaking table tests for critical equipment isolated with simple isolators were carried out in the Department of Civil Engineering, Feng Chia University, Taichung, Taiwan. From these test results, it is illustrated that the simple isolator can reduce more than 80% responses of accelerations under earthquakes with peak ground acceleration of above 0.450g. Therefore, the simple isolator can be recognized as a feasible and promising way in mitigating the seismic responses of equipment. In addition, the simple isolator possesses enough energy absorbing capacity to reduce its maximum displacement and the restoring force to bring the isolator back to the original position without significant residual displacement.

Shaking Table Test of Passive Controlled Structure With New Friction Damper

2007 ◽  
Author(s):  
Tadashi Mikoshiba ◽  
Chikahiro Minowa ◽  
Takanori Sato ◽  
Li Shao ◽  
Toshio Chiba
Keyword(s):  
Shaking Table Test ◽  
Large Earthquake ◽  
Shaking Table ◽  
Frame Structure ◽  
Friction Damper ◽  
Damping Characteristics ◽  
High Tension ◽  
Test Frame ◽  
Controlled Structure ◽  
Energy Dissipation Devices

Under the effect of a large earthquake, the range of plastic comes into the column and the beam of the frame structure. By using energy dissipation devices, it is possible to reduce the response and the damage of the structure. A friction type damper which was a compact form and had high damping characteristics, was developed. It was made of steel plate, aluminum sliding plate, rubber washer and high tension bolt. To validate the performance of the new damper, the elemental tests and the shaking table test were conducted. In the shaking table test, frame structure composed of full scale member with friction damper was excited by actual seismic wave. As a result, it was found effective and had a high damping performance. This paper mainly reports the results of the shaking table test.

Resilient Design of Buildings with Hysteretic Energy Dissipation Devices as Seismic Fuses

2019 ◽  
pp. 77-103 ◽  
Author(s):  
Arturo Tena-Colunga ◽  
Héctor Hernández-Ramírez ◽  
Horacio de Jesús Nangullasmú-Hernández
Keyword(s):  
Energy Dissipation ◽  
Hysteretic Energy ◽  
Resilient Design ◽  
Energy Dissipation Devices
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