Journal of Korean Society of Steel Construction (한국강구조학회 논문집)

Korean Society of Steel Construction (한국강구조학회)
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Flexural-Torsional Free Vibrations of Circular Strip Foundation with Variable Breadth on Pasternak Soil

Pasternak지반으로 지지된 변화폭 원호형 띠기초의 휨-비틀림 자유진동

  • 이병구 (원광대학교 토목환경도시공학부) ;
  • 박광규 (대전대학교 토목공학과) ;
  • 강희종 (원광대학교 대학원 토목환경공학과) ;
  • 윤희민 (원광대학교 대학원 토목환경공학과)
  • Received : 2007.06.13
  • Accepted : 2007.09.20
  • Published : 2007.10.27
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Abstract

This paper deals with flexural-torsional free vibrations of the circular strip foundation with the variable breadth on Pasternak soil. The cross-section of the strip foundation is chosen as the rectangular one with the constant thickness and variable breadth, which is symmetrical about the mid-arc. Also, the foundation that supports the circular strip is modeled as the Pasternak soil with the shear layer. Ordinary differential equations accompanying the boundary conditions are derived. In the governing equations, the transverse, rotatory and torsional inertias are included. These equations are solved numerically and four lowest frequencies are obtained. In the numerical results, the effects of foundation parameters on frequencies are extensively investigated. It is expected that the theories and numerical results of this study can be used in the dynamic design of strip foundations.

이 논문은 Pasternak지반으로 지지된 변화폭 원호형 띠기초의 휨-비틀림 자유진동에 관한 연구이다. 띠기초의 단면은 단면깊이는 일정하고, 단면폭은 1차식으로 변화하는 변화폭을 갖는 직사각형 단면으로 채택하였다. 띠기초의 지반은 Winkler지반에 전단층을 갖는 Pasternak지반으로 모형화하였다. 이러한 원호형 띠기초의 자유진동을 지배하는 상미분방정식과 경계조건을 유도하였다. 자유진동의 관성항으로는 휨관성, 회전관성 및 비틀림관성을 고려하였다. 상미분방정식을 수치해석하여 4개의 최저차 고유진동수를 산출하였다. 수치해석의 결과로 띠기초의 변수들이 고유진동수에 미치는 영향을 고찰하였다. 이 논문의 결과는 띠기초의 동적 설계에 매우 유용한 자료를 제공할 수 있을 것으로 기대된다.

Keywords

Acknowledgement

Supported by : 원광대학교

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