混凝土建物長年使用產生的表面損壞可以透過目視檢測辨識損壞狀況，但是檢測倚賴專業人員經驗且具危險性。近年來深度學習蓬勃發展已在各領域廣泛應用，可使用深度學習影像辨識模型輔助檢測。因此本研究的目標為建立一套實時辨識鋼筋混凝土表面裂縫與鋼筋外露的深度學習模型。
本研究主要分為兩部分，第一部分是建立裂縫圖像辨識模型，模型包含6層的神經網路，其正確率可以達到99.1%。第二部分是建立混凝土損壞影像辨識模型，採用Keras函式庫建立的YOLOv3神經網路，使用不同條件的樣本，逐步增加損壞類別，損壞類型包含裂縫、鋼筋外露以及裂縫分支。透過mAP、loss及影片檢測效果評估模型，最後再使用效果最好的模型進行實時辨識的測試。
影像辨識模型的分為四種：一般裂縫模型、橋梁裂縫模型、兩類損壞模型及三類損壞模型。一般裂縫模型分為三種條件，皆採用3510張樣本訓練，其中包含同樣數量的正負樣本，以不同類型的照片取代同樣比例的負樣本，其中加入建築照取代負樣本的模型裂縫AP最高，可以達到83.61%，但影片效果不佳，所以並未繼續採用此作法。橋梁裂縫模型在一般裂縫模型的基礎上繼續加入橋梁檢測照片，裂縫AP最高為69.38%，影片效果更優於一般裂縫模型，所以採用此作法繼續加入鋼筋外露的類別。兩類損壞模型所有類別mAP最高可以達80.57%，且影片效果也最好，最後採用此類模型進行實時辨識的測試。三類損壞模型加入裂縫分支的類別，以探討該裂縫分類法對於裂縫辨識成效的影響。針對上述模型做定量分析及影片效果比較後，最終以兩類損壞模型作為實時辨識系統的效果測試。
實時辨識的測試場所選於台南市安南區鹽水溪周邊橋梁，測試採用手機視訊電腦進行，並另外拍攝影片進行影像辨識，比較實時辨識與影片辨識的差異。結果顯示，鋼筋外露與裂縫在實時辨識與影片辨識中皆有相當良好的辨識成效。

Visual inspection is one of the commonest approaches in the field of Structural Health Monitoring (SHM). However, the works rely heavily on the inspectors’ knowledge and experience leading to subjective assessments. On the other hand, with the rapid development of the Convolution Neural Network (CNN), deep learning technique has been widely adopted for damage detection. In this study, a real-time concrete surface damage detecting system was developed based on YOLOv3 network. The influences of using different types of datasets for training on the accuracy of the models was also investigated.
The study is divided into three parts: image, video and real-time objects detection. First, an image classification model is developed for the recognition of the cracked and uncracked concrete images. Second, for the object detection in video, YOLOv3 was used for the crack and spalling detection using different types of datasets. The model with the best performance was therefore adopted for the real-time surface damage detection.
Consequently, four locations in Tainan City were selected for the validation of the real-time damage detection model. The results show that the real-time damage detection model has an outstanding performance with an AP of 79.78% in the detection of concrete crack and AP of 81.35% for the exposed rebar damages.

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