Seismic response of underground utility tunnels: shaking table testing and FEM analysis

With the main objective of providing basic information for calibration of analytical models and procedures for determining seismic response of historic stone masonry buildings, a shaking table testing program was undertaken at the Institute of Engineering of UNAM. A typical colonial temple was chosen as a prototype. The model was built at a 1:8 geometric scale. Increasing levels of seismic intensities were applied to the table. Main features of the measured response are compared in this paper to those computed though a nonlinear, finite element model; for the latter, a constitutive law corresponding to plain concrete was adopted for reproducing cracking and crushing of the irregular stone masonry, which could be considered as a conglomerate with low anisotropy. From the results of the analytical models, it was found that response is strongly governed by damping coefficient and tensile strength of masonry. Measured damping coefficients were found to significantly exceed those commonly used for modern structures. Observed damage patterns as well as measured response could be reproduced with a reasonable accuracy by the analytical simulation, except for some local vibrations, as those at the top of the bell towers.

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Real-time hybrid shaking table testing method for the performance evaluation of a tuned liquid damper controlling seismic response of building structures

Journal of Sound and Vibration ◽

10.1016/j.jsv.2006.12.006 ◽

2007 ◽

Vol 302 (3) ◽

pp. 596-612 ◽

Cited By ~ 55

Author(s):

Sung-Kyung Lee ◽

Eun Churn Park ◽

Kyung-Won Min ◽

Sang-Hyun Lee ◽

Lan Chung ◽

...

Keyword(s):

Performance Evaluation ◽

Seismic Response ◽

Real Time ◽

Shaking Table ◽

Building Structures ◽

Tuned Liquid Damper ◽

Testing Method ◽

Shaking Table Testing

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Effect of Acceleration on Wrap Faced Reinforced Soil Retaining Wall on Soft Clay by Performing Shaking Table Test

Proceedings of Engineering and Technology Innovation ◽

10.46604/peti.2020.4485 ◽

2020 ◽

Vol 15 ◽

pp. 24-34 ◽

Cited By ~ 1

Author(s):

Ripon Hore ◽

Sudipta Chakraborty ◽

Ayaz Mahmud Shuvon ◽

Mehedi Ahmed Ansary

Keyword(s):

Seismic Response ◽

Pore Water ◽

Empirical Data ◽

Retaining Wall ◽

Soft Clay ◽

Reinforced Soil ◽

Shaking Table ◽

Fixed Frequency ◽

Shaking Table Testing ◽

Sinusoidal Input

This research incorporates shaking table testing of scale wrap faced soil wall models to evaluate the seismic response of embankment. Currently the seismic designs of highway or railway embankment rely on little or no empirical data for calibrating numerical simulations. This research is working towards filling that empirical data gap. The specific purpose of the study was to evaluate the seismic response of constructed embankment model regarding the different input base accelerations with fixed frequency. A series of one-dimensional (1D) shaking table tests (0.05g, 0.1g, 0.15g and 0.2g), were performed on a 0.4 meters high wrap faced reinforced-soil wall model. Additionally, it was placed over 0.3 meters high soft clayey foundation. Predominantly, the influence of the base acceleration on the seismic response was studied in this paper. The physical models were subjected to harmonic sinusoidal input motions at a fixed frequency of 1 Hz, in order to assess the seismic behavior. The effects of parameters such as acceleration amplitudes and surcharge pressures on the seismic response of the model walls were considered. The relative density of the backfill material was kept fixed at 60%. The results of this study reveal that input accelerations and surcharge load had significant influence on the model wall, pore water pressure, and changes along the elevation. Acceleration response advances with the increase in base acceleration, so the difference being more perceptible at higher elevations. The pore water pressures were found to be high for high base shaking and low surcharge pressures at higher elevations. The results obtained from this study are helpful in understanding the relative performance of reinforced soil retaining wall under different test conditions resting on soft clay.

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Seismic Response for a One-Third Scale-Down Vertical Cylindrical Cask Specimen Using Shaking Table Testing

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.764-765.1119 ◽

2015 ◽

Vol 764-765 ◽

pp. 1119-1123

Author(s):

Wei Ting Lin ◽

Yuan Chieh Wu

Keyword(s):

Finite Element ◽

Friction Coefficient ◽

Seismic Response ◽

Harmonic Excitation ◽

Shaking Table ◽

Engineering Practice ◽

Spent Fuel ◽

Shaking Table Tests ◽

Finite Element Software ◽

Shaking Table Testing

This study is aimed to investigate the seismic behavior of the freestanding dry storage cask for spent fuel, several shaking table tests were conducted using a scaled cask model for a real assessment of the characteristics of the seismic response of the cask. First, the harmonic excitation test on the pedestal of the cask was performed to estimate the friction coefficient at the interface between the cask and the pad according to the sliding acceleration response of the pedestal. Then, tests for the seismic response of the cask were conducted for two different setups, the vertical cylindrical concrete cask (VCC) and the concrete cask with an add-on shield which has a square pedestal (VCC+AOS), respectively, using the artificial earthquakes compatible to the design spectrum. In order to verify the often-used analysis method for the seismic response of the cask in engineering practice, the explicit finite element software LS-DYNA was adopted to generate the finite element model of the scale cask with the cask/pad interface modeled by Coulomb’s law of friction and to simulate the shaking table tests. Results indicate that the utilized method gave reasonable cask responses if the variation of the friction coefficient at the cask/pad interface was small during the sliding process.

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