- 期刊
考慮海床地層參數變異性之離岸風場CPT場址放大效應評估
EVALUATION OF SITE-SPECIFIC AMPLIFICATION EFFECT AT CPT SITE IN OFFSHORE WIND FARM CONSIDERING THE VARIABILITIES OF SITE VELOCITY PROFILE AND NONLINEAR PROPERTIES
摘要
一般地震危害度分析得到之場址設計反應譜係屬工址參考岩盤露頭反應譜，但實際離岸風機支撐結構之海下基礎可能僅深入海床沉積土層而未深入岩盤，需考慮風機工址地層對震波之放大效應。本研究針對彰化外海離岸風場CPT場址實際案例，以不同回歸期之均布危害度反應譜作為輸入運動，同時考量海床波速剖面以及地層材料之非線性性質的變異性，進行海床地盤受震反應分析，得出在不同地震回歸期下該場址放大函數之統計結果。本研究所建立之評估流程，可供現行台灣離岸風場開發設計驗證相關地震力評估工作的參考，而分析所得之放大函數亦可作為建立場址地表危害度曲線與後續風機耐震風險評估應用。
並列摘要
The design response spectrum of Offshore Wind Farm (OWF) obtained from the probabilistic seismic hazard analysis is identified as the outcropping motion of site reference rock. At OWF site usually with shallow soft layers which shear wave velocity is less than the reference bedrock defined in PSHA, a site response analysis should be performed to assess the site amplification effect and obtain ground seismic responses. This study is based on the actual case of the CPT site in Changhua offshore wind farm. Using the Uniform Hazard Response Spectra (UHRS) as input motion and considering the variability of seabed wave velocity profile and non-linear properties of the seabed material, the site response analysis is performed to evaluate site-specific amplification effect. The evaluation process established by this study could be a reference for the current work related to the development and verification for the seismic demand of OWF in Taiwan.