世界各國有關於鹼-骨材反應的試驗規範，主要以量測砂漿棒(ASTM C227或ASTM C1260)或混凝土角柱(ASTM C1293)試體在特定環境條件下(包括溫度、溼度或鹼性溶液)膨脹量再繪製成膨脹歷時曲線。傳統的量測方式乃採用刻度式比長儀或多點式應變計，所獲得的數據僅為長度變化量，本研究嘗試利用平台式掃描器擷取鹼-骨材反應試體影像，經過處理可獲得膨脹量，且可將數位影像加以保存。本研究結果顯示，利用掃描器擷取影像作為膨脹量量測，具可行性。此外，不同齡期所擷取的試體表面影像，亦可探究裂縫生長行為，由於掃描之影像具有良好的解析度，可在肉眼尚無法看出裂縫時，即能利用影像放大的方式，清楚在影像上判讀裂縫，影像除可判讀亦具有良好的保存性，相當適合試驗後的後續追蹤檢核。以掃描器擷取影像判讀膨脹量方法，除具上述優點外，與多點式應變計相較，另具有資料可檢核、費用便宜與維修方便等優點。 Most of the standard test methods for potential alkali reactivity of aggregate around the world measure the expansion of mortar bars (ASTM C227 or ASTM C1260) or concrete prisms (ASTM C1293) with comparators or multi-length strain gauge set under certain conditions (inclusive of temperature, moisture or alkaline supply) and draw the curve of expansion to time duration. The result can only show the change in length. This research tends to use a scanner to get a surface image of a specimen with AAR, which can be analyzed for expansion and stored digitally. Result include that it's application to measure the expansion of specimen with digital image required with a commercial scanner. With images acquired from same specimen in different time, one can trace the crack development. With higher resolution images, one can zoom in to recognize the crack even if it is too small to recognize with bare eyes. Digital images can be easily stored and traced back for data checking. In comparison with multi-length strain gauge set, the method of image measurement spends less, gets more, and easy to maintain a good quality of measurement.