Load-Deflection Analysis of RC Beam Strengthened by External Steel Plate

外貼鋼板補強之鋼筋混凝土梁載重位移分析

林文山(Wen-Shan Lin)

《中華技術學院學報》 36期 (2007/06) Pp. 1-16

https://doi.org/10.7095/JCIT.200706.0001

摘要

本文利用Brason所提出之有效慣性矩，加以修正來預測外貼鋼板補強之鋼筋混凝土梁之載重位移分析，其載重位移曲線可視為四線性曲線，各分界點分別為混凝土開裂點、補強鋼板降伏點、拉力筋降伏點和混凝土壓碎點，利用基本之材料力學、鋼筋混凝土力學及割線模數觀念，將鋼板和鋼筋降伏後，以其割線模數比(平均值)n(下標 p)=(平均值)E(下標 p)/E(下標 c)和(平均值)n(下標 s)=(平均值)E(下標 s)/E(下標 c)取代未降伏之割線模數比n(下標 p)=E(下標 p)/E(下標 c)和n(下標 s)=E(下標 s)/E(下標 c)來決定降伏、開裂後之轉換斷面的慣性矩，求出上述點之載重及位移，文中並舉詳細計算例過程，其預測結果與實驗和有限元素法相比較有很好的吻合度，顯示利用割線模數比來修正Brason所提出之有效慣性矩，可有效預測外貼鋼板補強之鋼筋混凝土梁之載重位移分析。

關鍵字

鋼板補強鋼筋混凝土梁 ； 載重位移曲線 ； 割線模數

並列摘要

This paper presents the RC beams strengthened by external steel plate have been analyzed by modified Brason's equation to predict load-deflection curve. Estimation of the yielding of both steel plate and steel bar point in the load deflection curve is attained using the elementary procedures of strength of materials. But using the secant modulus concept, the replace a secant modular ratio (average)n(subscript p)=(average)E(subscript p)/E(subscript c) and (average)n(subscript s)=(average)E(subscript s)/E(subscript c) with modular ration n(subscript p)=E(subscript p)/E(subscript c) and n(subscript s)=E(subscript s)/E(subscript c) to determine cracked transformed section moment of inertia when after yielding of both steel plate and steel bar. The scope of the study is limited to RC beam strengthened by steel plates externally bonded to the tension face that exhibits the flexure mode of failure. Comparing calculated load-deflection responses with experimental data and finite element prediction reported in previous literature checked the accuracy of proposed procedure.

並列關鍵字

RC beam strengthened by external steel plate ； load-deflection curve ； secant modulus