Behavior of Circular Flexible Foundations under Dynamic Loading

博士 === 國立臺灣科技大學 === 營建工程系 === 97 === In foundation vibration problems, the assumption of foundations being rigid is not always valid. Hence, this dissertation develops a new modal flexibility method and an efficient ring method to efficiently calculate modal impedance functions and evaluate dynamic...

Full description

Bibliographic Details
Main Authors: Chin-Kang Hou, 侯志剛
Other Authors: Shi-Shuenn Chen
Format: Others
Language:en_US
Published: 2009
Online Access:http://ndltd.ncl.edu.tw/handle/64181946808424914285
id ndltd-TW-097NTUS5512093
record_format oai_dc
spelling ndltd-TW-097NTUS55120932016-05-02T04:11:47Z http://ndltd.ncl.edu.tw/handle/64181946808424914285 Behavior of Circular Flexible Foundations under Dynamic Loading 圓形柔性基礎承受動態載重之行為 Chin-Kang Hou 侯志剛 博士 國立臺灣科技大學 營建工程系 97 In foundation vibration problems, the assumption of foundations being rigid is not always valid. Hence, this dissertation develops a new modal flexibility method and an efficient ring method to efficiently calculate modal impedance functions and evaluate dynamic response of a circular flexible foundation subjected to horizontal, vertical, and rocking motions. The displacement of flexible foundations is expressed in terms of modal shapes corresponding to free vibration of a circular plate, and dynamic interaction effects between the foundation and the underlying soil are represented using modal impedance functions. Comparing with existing solutions, both developed methods are found to provide accurate results with less computational effort. Verified by SASSI program, it is also found that the coupling effect between horizontal and rocking motions can be considered adequately by the proposed methods. In addition, parametric analysis are performed to investigate the influence of the load distribution, the vibration frequency range, the foundation mass, boundary-contact condition, and the relative stiffness between the foundation and the soil medium on the dimensionless modal response. The required numbers of modes for different load distributions and the relative stiffness ratio and justification for flexible foundations to be considered as rigid are suggested. Besides, the modal impedance functions and approximate solutions for the dynamic displacement of flexible foundations can be easily obtained, and the effect of flexible foundations can also be quickly evaluated. Shi-Shuenn Chen 陳希舜 2009 學位論文 ; thesis 139 en_US
collection NDLTD
language en_US
format Others
sources NDLTD
description 博士 === 國立臺灣科技大學 === 營建工程系 === 97 === In foundation vibration problems, the assumption of foundations being rigid is not always valid. Hence, this dissertation develops a new modal flexibility method and an efficient ring method to efficiently calculate modal impedance functions and evaluate dynamic response of a circular flexible foundation subjected to horizontal, vertical, and rocking motions. The displacement of flexible foundations is expressed in terms of modal shapes corresponding to free vibration of a circular plate, and dynamic interaction effects between the foundation and the underlying soil are represented using modal impedance functions. Comparing with existing solutions, both developed methods are found to provide accurate results with less computational effort. Verified by SASSI program, it is also found that the coupling effect between horizontal and rocking motions can be considered adequately by the proposed methods. In addition, parametric analysis are performed to investigate the influence of the load distribution, the vibration frequency range, the foundation mass, boundary-contact condition, and the relative stiffness between the foundation and the soil medium on the dimensionless modal response. The required numbers of modes for different load distributions and the relative stiffness ratio and justification for flexible foundations to be considered as rigid are suggested. Besides, the modal impedance functions and approximate solutions for the dynamic displacement of flexible foundations can be easily obtained, and the effect of flexible foundations can also be quickly evaluated.
author2 Shi-Shuenn Chen
author_facet Shi-Shuenn Chen
Chin-Kang Hou
侯志剛
author Chin-Kang Hou
侯志剛
spellingShingle Chin-Kang Hou
侯志剛
Behavior of Circular Flexible Foundations under Dynamic Loading
author_sort Chin-Kang Hou
title Behavior of Circular Flexible Foundations under Dynamic Loading
title_short Behavior of Circular Flexible Foundations under Dynamic Loading
title_full Behavior of Circular Flexible Foundations under Dynamic Loading
title_fullStr Behavior of Circular Flexible Foundations under Dynamic Loading
title_full_unstemmed Behavior of Circular Flexible Foundations under Dynamic Loading
title_sort behavior of circular flexible foundations under dynamic loading
publishDate 2009
url http://ndltd.ncl.edu.tw/handle/64181946808424914285
work_keys_str_mv AT chinkanghou behaviorofcircularflexiblefoundationsunderdynamicloading
AT hóuzhìgāng behaviorofcircularflexiblefoundationsunderdynamicloading
AT chinkanghou yuánxíngróuxìngjīchǔchéngshòudòngtàizàizhòngzhīxíngwèi
AT hóuzhìgāng yuánxíngróuxìngjīchǔchéngshòudòngtàizàizhòngzhīxíngwèi
_version_ 1718254470583812096