Shaking table test and analysis method on ultimate behavior of slender base-isolated structure supported by laminated rubber bearings

This paper describes the dynamic damage test of a reinforced concrete (RC) wall structure with seismic isolation sysytem. It has been expected that seismically isolated structures are damaged in sudden when the accelerations of the structures exceed a certain level by hardening of the rubber bearings. However, the response behavior and the damage mode have not been observed by experimental test yet. So, shaking table tests were carried out at “E-Defense”, equipping the world’s largest shaking table, located at Miki City, Hyogo prefecture, Japan. The specimen was composed of an upper structure of 600 ton by weight and six lead-rubber bearings (LRBs) of 505 mm in diameter which provide both stiffness and hysteretic damping. The upper structure consisted of a RC mass and four RC walls with counter weight. The RC wall structure was designed so that the damage of the RC wall occurred between the shear force at the hardening of the rubber bearings and that at their breaking. The dimensions of the RC wall were 1600 × 800 × 100 mm (B × H × t). The reinforcement ratios were 2.46% in vertical by D13 (deformed reinforcing bar, 13 mm in diameter) and 1.0% in horizontal by D10. The shaking table test was conducted consecutively by increasing the levels up to 225% of tentative design earthquake motion. Consequently, because of the increase of the structural response by the hardening of the rubber bearings, the damage of the wall structure with seismic isolation system suddenly happened. In addition, the preliminary finite element analysis simulated the test results fairly well, which were the restoring force characteristics, the crack patterns of the RC wall structure and such.

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Applicability of Seismic Fatigue Evaluation by JSME Code Case, NC-CC-008

Volume 8: Seismic Engineering ◽

10.1115/pvp2019-93123 ◽

2019 ◽

Author(s):

Akihito Otani ◽

Izumi Nakamura ◽

Tomoyoshi Watakabe ◽

Masaki Morishita ◽

Tadahiro Shibutani ◽

...

Keyword(s):

Evaluation Method ◽

Shaking Table Test ◽

Shaking Table ◽

Evaluation Methodology ◽

Response Analysis ◽

Analysis Method ◽

Seismic Evaluation ◽

Fatigue Evaluation ◽

Conservative Result ◽

Current Rule

Abstract A Code Case, JSME S NC1, NC-CC-008, in the framework of JSME Nuclear Codes and Standards has been published. New seismic evaluation methodology for piping by utilizing advanced elastic-plastic response analysis method and strain-based fatigue criteria has been incorporated into the code case. It can achieve more rational seismic design than the current rule. This paper demonstrates validity and applicability of fatigue evaluation method proposed in the code case. Experimental results of a shaking table test for a piping model is used for comparing the evaluation by the current rule with one by the code case. As a result, it is confirmed that the code case can provide a rational and conservative result in the fatigue evaluation of piping. Moreover, cycle counting in the fatigue evaluation was examined for further progress of the code case.

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Comparative Study on Nonlinear Earthquake Response of Girder Isolated Bridges with LRB and Model Shaking Table Test

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.706-708.472 ◽

2013 ◽

Vol 706-708 ◽

pp. 472-477

Author(s):

Jie Dong Zhan ◽

Xin Tong Li ◽

Yang Li

Keyword(s):

Seismic Response ◽

Shaking Table Test ◽

Experimental Results ◽

Shaking Table ◽

Vertical Force ◽

Isolation System ◽

Nonlinear Seismic Response ◽

Girder Bridges ◽

Deformation Properties ◽

Rubber Bearings

Abstract: The thesis is aimed to study the characteristics nonlinear seismic response of the isolated continuous girder bridges with LRB. Inorder to achieve the aim, force- deformation properties of the LRB is considered as bilinear first, the bouc-wen model is adopted to imitate the force nonlinear deformation behavior of LRB, and by using Finite element method, the motion equation of the Isolation system of continuous girder bridge is established, then some shaking table tests towards the model of isolated continuous girder bridges with LRB is done. On this basis of it, by comparing the experimental results and calculation results, such as the acceleration and displacement of deck, vertical force of bearing, and the relationship between the Isolation layer displacement and the Level force displacement of the Bearing, we can see that the difference between the analytical results and the experimental results are very small. The results show that the calculation method can analyze Nonlinear Seismic Response of isolated continuous girder bridges with LRB efficiently. But when the vertical earthquake component is larger ,whether the results of the Vertical tension are produced or not, designing the Rubber bearings should be considered.

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Experimental Investigation on Mid-Story Isolated Structures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.163-167.4014 ◽

2010 ◽

Vol 163-167 ◽

pp. 4014-4021

Author(s):

Xiang Yun Huang ◽

Fu Lin Zhou ◽

She Liang Wang ◽

Liu Han Wen Heisha ◽

Xue Hai Luo

Keyword(s):

Dynamic Characteristics ◽

Shaking Table Test ◽

Base Isolation ◽

Shaking Table ◽

Dynamic Responses ◽

Seismic Responses ◽

Isolation Technique ◽

Vertical Stiffness ◽

Isolation Layer ◽

Rubber Bearings

Isolation technique has been acceded as a part of the China Seismic Code for Design of Buildings. In this code, the limitations for using isolation design are very strict, superstructure must be regular and the isolation layer must be located on the top of base (base isolated structure). Because of the needs of architecture and function or the feasibility of technique, some limitations have been broken in recent projects. Sometimes isolated layer can be set on the intermediate story, so-called the mid-story isolated structure. According to the characteristic of structure, isolation layer of mid-story isolated structure is set on a place where the structure’s vertical stiffness is suddenly changed, as like the top of the first story, middle story, conversion story of the structure. Laminated rubber bearings (LRB) are adopted as an isolation layer. Because the isolation layer is set on intermediate story, the whole structure is divided into superstructure and substructure; the structure’s dynamic characteristics are changed. The mechanism of mid-story isolated structure appears different characteristic compared with base isolation. The aim of mid-story isolation is not only to reduce seismic responses of superstructure, but also to reduce seismic responses of the substructure. Theoretical analysis and the shaking table test of the mid-story isolated structure were carried. And the response of mid-story isolated structure is discussed by comparing with the response of base-isolated structure and base fixed structure. The key problems of mid-story isolated structure are the force condition and the interaction of the structure up and below the isolation layer. Many factors, such as the number of story, mass, stiffness of superstructure and substructure, parameter of the isolation layer, have influence on the seismic behavior of the mid-story isolated structure. The optimum combination relationship of these factors is presented and dynamic characteristics and dynamic responses are investigated.

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EVALUATION ON DAMAGE AND RESIDUAL PERFORMANCE OF LEAD RUBBER BEARINGS AFTER THE SHAKING TABLE TEST

Journal of Structural and Construction Engineering (Transactions of AIJ) ◽

10.3130/aijs.79.731 ◽

2014 ◽

Vol 79 (700) ◽

pp. 731-740

Author(s):

Seiji NAGATA ◽

Shuichi YABANA ◽

Kenji KANAZAWA ◽

Kazuta HIRATA ◽

Katsuhiko UMEKI ◽

...

Keyword(s):

Shaking Table Test ◽

Shaking Table ◽

Lead Rubber Bearings ◽

Residual Performance ◽

Rubber Bearings

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Acceleration Data Acquisition and Analysis Method of Shaking Table Test

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.724.205 ◽

2015 ◽

Vol 724 ◽

pp. 205-212 ◽

Cited By ~ 1

Author(s):

Shao Feng Chai ◽

Ping Wang ◽

Zhi Jian Wu ◽

Jun Wang ◽

Gao Feng Che

Keyword(s):

Data Processing ◽

Test Data ◽

Shaking Table Test ◽

Damping Ratio ◽

Shaking Table ◽

Amplification Coefficient ◽

Response Analysis ◽

Analysis Method ◽

Stability And Instability ◽

Sine Sweep

Shaking table test is an important means of simulated earthquake in laboratory, slope shaking table test data provide a scientific basis for analysis of dynamic stability and instability mechanism of slopes. Sine vibration table test data processing is different from general frequency domain analysis method, need real-time data processing in time domain. Taking the sine sweep test conditions, which is one of the conditions in "Earthquake landslide and slope prevention and control technology research on shaking table test", as an example. Describes the layout of sensors in shaking table test and the reasons; Sine sweep test load and aim; and listed the steps and methods of the sine sweep test in data processing; Through the processing and analysis of test data identified the vibration frequency of model and shaking table system is 30Hz, damping ratio is 2.06%; Analysis and calculation of the different sections of the slope and position of the amplification coefficient. A methodological guidance for shaking table test and dynamic response analysis of the slope is provided.

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