|
碩士論文公告區 |
||
| 年度： | 90 | |
| 姓名： | 洪英州(Yin-Chou Hung) | |
| 論文題目(中)： | 地下室開挖形狀對震波散射問題之數值研究 | |
| 論文題目(英)： | Numerical Analysis of Wave Scattering ffect Due to Shape of Basement Excavations | |
| 摘要(中)： | ||
| 在921地震後，經觀察發現，半開挖式地下室結構損毀情形大部分比全開挖式結構嚴重。在影響因素中，學者普遍認為導致此種現象之主要因素為震波入射於不規則地形產生散射及繞射現象引起地表位移放大效應。因此，探討如何降低震波入射於不規則地形之地表位移已成為重要的課題。 本文利用二維頻率域邊界元素法解析六種開挖形式及地下室嵌於無限半平面表面在受P，SV波或Rayleigh波入射後對開挖形式或地下室表面位移變化情形並加以評估，討論及分析，以作為日後施工時之參考。在分析比較不同開挖形式及地下室位移變化中，除在高頻時，左半開挖形式造成的水平及垂直位移比全開挖形式及右半開挖形式還大。所以可推估地震來時半開挖形式中，若半開挖側與入射方向同側時會發生較大的位移反應。而三種開挖形式在頻率較低時，因散射及繞射效應較不明顯，所以在水平位移平均比及垂直位移平均比差距都較小。而高頻時則依照各種入射波及入射角而有不同散射及繞射效應，所以水平位移平均比及垂直位移平均比差距較大。 |
||
| 摘要(英)： | ||
| Field observations after 921 earthquake show that the irregular basement has serious damage because of amplification of ground motion. Profession think that one of the principal causes for the damage may be attributed to the amplification of incident waves by local irregular topography. This paper is to study the wave scattering of P, SV and Rayleigh waves in the excavation or the basement embedded in homogeneous, elastic and isotropic half plane by using the 2-D frequency domain boundary element method. The influence of key parameters, such as the shape of excavation or basement, frequency, and angle of incidence on surface ground motion are studied in detail. In the higher frequency, the displacement amplitude ratio of left-half excavation is larger than that of right-half excavation and open excavation. In lower frequency, the difference of the displacement amplitude ratio between three excavation types may be ignored, for the reason of less scattering or diffraction of waves. However, the effects of the scattering and diffraction of waves, the displacement amplitude ratio are more influenced in the higher frequency. |
||
| 檔案： | 沒有相關檔案 | |
| 相關連結： | http://ethesys.lib.cyut.edu.tw/ETD-db/ETD-search-c/view_etd?URN=etd-0718102-165527 | |