本計畫主要執行三年，探討國內老舊民間建物與校舍特色，混凝土強度較低時RC結構物耐震行為，以及利用傳統RC擴柱補強後之耐震成效。計畫主要執行實尺寸RC構架實驗，利用申請者專長在大型構架實驗經歷，於前兩年進行，來探討以往未重視之混凝土強度很低問題，其RC構件抗彎與抗剪行為，是否適用於以一般混凝土構件經驗作評估。再者，上述問題常伴合構件鋼筋有缺失情況。故當急之務，則以實際RC實驗為基礎，討論極軟弱RC原型構架耐震性，以及RC擴柱補强後抗震提升能力。計畫第三年，則主要研究如何評估如此軟弱結構耐震行為。一般均以傳統結構推垮分析做評估，然而本研究將以桁架分析模式為基礎，可仔細模擬鋼筋有缺失RC構架之情況，這也是改進並延續申請者之前研究成果。雖然兩分析方法各有利弊，但本計畫思考如何結合桁架分析模式於傳統RC結構非線性推垮分析。相信本計畫執行完畢後，必能對國內老舊建物耐震評估與補強有所貢獻，這也是申請者申請本計畫目的。 The project is carried out for three years. The target of the research is to understand the seismic behavior of reinforced concrete structures with very low concrete strength and substandard reinforcing details. These structures are characterized as a typical Taiwan low-rise dwelling houses and school buildings constructed in the age of pre-1970s. Of particular interest is to know the seismic resistance performance after these nonductile buildings are retrofitted using the popular RC jacketing scheme, for many retrofit projects in high and elementary schools are underway. Full-scale RC column elements and frames will be tested for two years. This is because, nowadays, no such investigation on the RC nonductile buildings with very-low concrete strength is found. It is urgent to realize the behavior of these substandard buildings for the recent demand. Besides the experimental works, the assessment on the as-built nonductile building will be mainly studied for the final year. Truss analysis methodology is adopted into the main topic. So far the truss analogy is developed for few years and will be extended continuously. The nonductile behavior of the building with substandard reinforcement could be easily understood by means of truss analysis results. However, a traditional nonlinear pushover analysis is also used for comparison. Final conclusion would be focused on how to combine these two analytical methods in an effective way. Thus a better retrofit scheme can be proposed in the near future. 研究期間：10008 ~ 10107