本研究以無限小元素分析法，分析及探討裂縫長度對混凝土與碳纖維結合邊界裂縫尖端點之奇異性應力及補強效果的影響；發現奇異性階數λ值為0.5，因此裂縫長度對奇異性階數沒有影響；裂縫長度與梁長比（a╱L）小於0.125時，對補強效果影響不大，但a╱L介於0.125~0.35時，補強效果急劇下降，a╱L大於0.45時，補強構材則失去應提供之強度與韌性，應再加以維修。In this research, the analysis concept of infinitely small element is applied to derive the stiffness matrix of two dimensional plane elements and combine the equilibrium equations to simplify the unknown parameters. These derived equations are used to analyze and investigate the singularity and reparable efficiency in which affected by silt length on the interface of concrete and Carbon Fiber. The analysis results show that the λ of singular order is 0.5. The values of singular order are not affected by silt length. However, the reparable efficiency is influenced by silt length. At the rate of silt length and length of beam less than 0.125, the efficiency of mend has taken less effect. However, at the rate from 0.125 to 0.35, the efficiency decreases urgently. When the rate is greater than 0.45, Carbon Fiber lost the strength and ductility. Thus, structure should be repaired again
