- 學位論文
預鑄節塊橋柱試驗及行為研究
Experimental Studies of Precast Segemental Concrete Bridge Piers
摘要
摘要 橋梁預鑄節塊工法是一結合預鑄產製及機械化吊裝的施工方 式，其在生產上由於採預鑄方式製造，因此品質控制較為穩定。此一 工法在橋梁上部結構已行之多年，然對下部結構而言，因礙於地震帶 的使用疑慮，因此雖然此一工法具有低環境衝擊、高機械化作業以及 快速施工等優點，但目前台灣仍處於學術研究階段，有待進一步排除 施工障礙及疑慮。 本研究以後拉式預鑄工法橋柱為對象，探討後拉式預鑄橋柱於地 震帶應用的可行性，研究中針對四組大尺寸橋柱試體進行探討，其內 容包括無握裹的後拉式預力鋼腱橋柱以及有握裹的後拉式部分預力 鋼腱橋柱兩種，另外臨界斷面也採用不同的設計，以探討柱底半預鑄 介面、全預鑄介面以及鋼筋續接方式的影響。此外針對節塊介面的剪 力傳遞機制，也透過不同的介面剪力設計，了解其設計需求。而高達 11 公尺的試體製造與組立， 更可模擬真實橋柱的施工狀況， 評估未 來實際施工時的可能瓶頸， 以作為實務應用參考。 研究結果顯示本研究所發展之握裹性鋼腱預鑄節塊橋柱，在採用 適當的消能鋼棒的設計下，具有低殘餘變形及可觀的塑鉸消能，可應 用於地震頻繁地區。至於全預力無握裹性鋼腱橋柱，雖然具有低殘餘 變形的優點，但其消能能力不佳且強度偏低，在應用上宜搭配其它消 能機制較無應用的疑慮。
並列摘要
Abstract In the past 30 years, the use of post-tensioned precast segmental concrete in bridges has proven to be economical and durable. Similar techniques have been successfully applied to bridge piers in non-seismic regions. In many cases, post-tensioned substructure may allow construction that would otherwise become impossible due to either site or architectural constraints. Examples include bridges to be constructed in mountain areas or viaducts in urban area. In order to apply the precast segmental substructures into seismic regions, a two-year research program have been carried out at NCREE since Sep. 2001. This paper briefly described the test results of four large-scale post-tensioned precast segmental columns. The specimens consisted of 10 hollow rectangular precast segments which are scaled down from 50 m height piers in a moderate-span bridge. Post-tensioned tendons are used to stress the match-cast units. The fist one is a pure-tendon specimen pre-tensioned by eight 12.7 mm tendons. As commonly understood, pure-tendon columns pinched significantly with little energy dissipation capacity. The other three columns were combined tendons with mild steel bars in the bottom segments to improve the abilities of energy dissipation. Satisfactory test results were obtained. Lateral force was successfully transmitted through joints without using either shear keys or epoxies. The strength and ductility of the last three tested columns can meet the latest seismic design provisions in Taiwan.