隨著營建技術發展，多種工法及新穎材料逐漸應用於結構物上，且縮短工期、節省人力逐漸被重視，預鑄工法因而大量投入於現地中。本研究以超高性能纖維混凝土(Ultra-High Performance Concrete，以下簡稱UHPC)作為預鑄版材料，具有超高抗壓及抗拉強度，其內含之短纖維可有效強化受拉與受壓韌性，提升開裂強度與控制裂縫發展，並改善傳統混凝土脆性剝落問題，提升結構物耐震性能。利用UHPC卓越的力學特性，在不改變斷面大小前提下，同時探討UHPC預鑄版於RC柱新建預鑄模板工法與補強工法之有效性。
本研究方法採用柱構件之反覆側推載重試驗，以ACI 318-19設計並製作6做縮尺鋼筋混凝土柱，其中包含：2座控制組，分別設計為撓曲破壞控制之新建柱及剪力破壞控制之補強柱；2座以UHPC預鑄版作為模板直接進行核心混凝土澆置之新建柱試體，實驗參數為預鑄版內鋼筋網有無延伸進上下基礎；2座補強試體，分別以UHPC預鑄版進行包覆補強及UHPC場鑄補強，於軸壓比皆為0.2相同條件下，探討各種工法之耐震性能。
結果顯示，使用UHPC預鑄版作為新建模板工法，極限側向強度可提升43%~46%，使用UHPC預鑄版進行包覆補強與UHPC場鑄補強皆可提升65%，且所有試體韌性皆大幅提升，極限位移可達7%以上，更使柱體破壞模式從剪力破壞轉變為撓曲破壞。此外，預鑄版補強工法可達到與場鑄補強相近之效益，更可簡化施工過程並縮短工期。經實驗證實，本研究提供之新型UHPC預鑄版工法，均能有效提升整體構件之耐震性能。

Ultra-High Performance Concrete (UHPC) has ultra-high compressive, tensile strength and excellent crack width control ability. This study utilizes the excellent mechanical properties of UHPC to explore the effectiveness of the novel precast UHPC parts into the newly-built RC columns and retrofitting shear-deficient RC columns without changing the size of the cross-section. A number of RC columns were built, and experimentally tested under displacement reversals. The experimental parameters of the newly-built columns are extending or not the longitudinal rebars within the UHPC formwork into the foundation, and the retrofitted columns are designed with different reinforcing methods(cast-in-place UHPC jackets or installation of precast UHPC jackets). The result shows that under same axial ratio of 0.2, using precast UHPC parts as formwork, the ultimate lateral strength can be increased by 43%~46%, precast UHPC jackets and cast-in-place UHPC jackets for retrofitting columns can be both improved the ultimate lateral strength 65%. The toughness of all specimens has been greatly improved, the ultimate displacement can reach more than 7%, and even change the failure mode from shear failure to flexural failure. In addition, precast UHPC jackets can achieve similar benefits as cast-in-place UHPC jackets, and simplify the construction process and shorten the construction period. Experiments have confirmed that the novel precast UHPC parts provided in this study can overall improve the seismic performance.

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