|摘要: ||近幾年來，地震工程之國際發展趨勢正朝向所謂「性能導向地震工程」 (performance-based earthquake engineering, PBEE) 之大方向邁進，期能發展出一套使結 構物具有可預期之性能表現的設計方法。而位移設計法即為此性能設計要求下，較佳 之解決方案，因為控制了位移就等於是控制了結構物之變形與損壞程度。因此，地震 性能設計法（performance-based design，PBD）已成為目前世界各國工程設計規範的主 流，也將是台灣工程設計規範未來要走的方向。在國內，一般對於橋樑與建築等構造 物之耐震性能及設計方法有較多的探討，但對於土工結構物（如路堤、擋土牆）等鐵、 公路交通工程中不可或缺的土石構造物則較少論及。事實上，土工結構在過去的地震 歷史中，有非常多的破壞案例(含土壤液化破壞）。因此，土工結構的耐震性能表現， 及相應的設計方法，仍須投注相當心力進行較深入的研究！ 此外，九二一集集地震後，內政部(2005)新頒布之「建築物耐震設計規範及解說」， 及研議中之鐵路橋梁、公路橋梁規範等，均將設計地震提高為三級地震，增加考慮2500 年回歸期之最大考量地震。若無性能設計規範的配合，欲採用較大危害等級之最大考 量地震來作土工結構之耐震設計，將有實質上之困難。再者，不同場址條件所引致之 場址效應（site effect），也對土工結構之受震反應有很大的影響。因此，為了切合實務 設計上之需求，並強化國內在大地地震工程有關性能研究的內涵及不足之處，本研究 將利用氣象局之自由場強震測站所收集之完整的強震紀錄，及國家地震工程研究中心 所建置之強震測站地質資料庫，以路堤及擋土牆二類土工結構為重點，規劃三年的研 究期程，希望在土工結構之受震易損性評估（以變位為耐震性能指標），及其與場址條 件之關係上，進行較深入的研究與探討。屆時，此本土性資料的研究成果，將可作為 未來增修現行耐震設計規範中，有關土工結構耐震性能評估方法的參考。|
In these years, performance-based earthquake engineering (PBEE) has become the international development trend of earthquake engineering. The displacement-based design approach is the best algorithm for PBEE. Accordingly, seismic performance-based design (PBD) has become the main stream of the seismic design codes for civil engineering. It will be the future trend of the engineering codes in Taiwan. Although earthwork structures are one of the common structures in railway and highway engineering, there have been more studies concerning PBD for bridge and building structures than for earthwork structures. In fact, there are many destructive damages of earthwork structures based on the observations in the past earthquake events. Thus, the seismic performance of earthwork structures needs to be studied in depth. Additionally, in Taiwan, the new seismic design codes for buildings and bridges have incorporated a higher level of design earthquake with a return period of 2500 years after Chi-Chi earthquake. It will have great impact to the analysis and design of the earthwork structures. Furthermore, the seismic response of earthwork structures is affected by site effects greatly. Therefore, in order to meet the requirements of design practice, and enhance the research intensity of geotechnical earthquake engineering associated with PBD, this research will attempt to explore the problem. Currently, there are 686 free field seismograph stations set up by Central Weather Bureau (CWB) and more than 350 boreholes data of CWB strong motion stations investigated by National Center for Earthquake Engineering (NCREE) are ready at hand. Strong ground motions are recorded for each earthquake, and site conditions are explored for every CWB strong motion stations year by year. These records and site information can provide an abundant database for setting up a site classification criterion suitable for Taiwan, and for performing site response analyses to consider the site effects and evaluate the seismic response of earthwork structures. Thus, a three-year research program is planned to study the seismic fragility of earthwork structures in terms of displacement, and its relationship to the site conditions. The results thus obtained can provide a more reasonable approach for analysis and design practice of earthwork structures, and will be beneficial to be a reference basis for modifying the seismic design codes met the objectives of PBEE and PBD in the future.