Project/Area Number |
02805054
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
土木構造
|
Research Institution | YAMAGUCHI UNIVERSITY |
Principal Investigator |
MIURA Fusanori YAMAGUCHI UNIVERSITY, FACULTY OF ENGINEERING, PROFESSOR, 工学部, 教授 (60109072)
|
Project Period (FY) |
1990 – 1991
|
Project Status |
Completed (Fiscal Year 1991)
|
Budget Amount *help |
¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 1991: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1990: ¥1,000,000 (Direct Cost: ¥1,000,000)
|
Keywords | OFF-SHORE STRUCTURE / SEISMIC RESPONSE / ICE / NONLINEARITY / HYDRODYNAMIC PRESSURE / ANISOTROPY / SLIDING STABILITY / 地震応答解析 / 非線形解析 / 有限要素法 / 半無限要素 / 水との相互作用 / 動的相互作用 |
Research Abstract |
The purpose of this study is to investigate the effect of ice on the seismic response and dynamic stability against sliding of a large scale off-shore structure that is surrounded by thick ice. The general method for analyzing the nonlinear soil-structure-water-ice interaction system was proposed first. In the method, a simple semi-infinite element method is newly introduced to express the semi-infinitely extending water system. The accuracy of the method was demonstrated by using dam-water-foundation models. Then the nonlinear soil-structure-water-ice interaction system was analyzed by the two dimensional finite element method. In modeling the system, modified joint elements were used to simulate sliding phenomena at the interface between the soil and the structure base. The effect of the hydrodynamic pressure acting on the structural surface was examined by comparing the effect of virtual mass of water. Generally, the exact estimation of the hydrodynamic pressure gave the smaller response of displacements and velocities of the structure but larger accelerations than those obtained from the virtual mass method. The effect of the material nonlinearity of soil was examined. The effect was very small when the soil strength which was obtained from the laboratory test of the soil of the site. The effect of anisotropy of ice was also examined. The effect was not negligible when the ice becomes hard, i.e. the temperature was very low.
|