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題 名 | 木材壓縮試驗時試體表面溫度之變化=Changes in Surface Temperature of Wood Specimens during Compression Testing |
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作 者 | 黃國雄; 熊如珍; 郭美吟; | 書刊名 | 臺灣林業科學 |
卷 期 | 16:2 2001.06[民90.06] |
頁 次 | 頁125-132 |
分類號 | 436.187 |
關鍵詞 | 紅外線熱像儀; 熱像; 表面溫度; 壓縮試驗; Infrared thermography; Thermal image; Surface temperature; Compression test; |
語 文 | 中文(Chinese) |
中文摘要 | 本研究計畫旨在探討紅外線熱像儀應用於木材非破壞試驗之可行性,即木材受外力 產生變形時,由其表面溫度之變化檢測其缺點或破壞位置。試驗中採用杉木、扁柏、肖楠、 泡桐、柳桉與櫸木等六樹種為試材。參照CNS 453木材壓縮試驗法進行縱向壓縮試驗與橫向 壓縮試驗,使用紅外線熱像儀測定試體表面溫度之變化,由試果檢討試體之壓縮變形、破壞 與溫度上升之關係。 由縱向壓縮試驗六種試材之破壞情形與其熱像得知試體破壞位置與試體表面溫度上升之 位置一致,顯示木材於縱向壓試驗中,當試體破壞時將所儲存之能量釋放出而使其破壞位置 之表面溫度明顯上升,當在比例限度以下時,試體表面最高溫度幾乎沒有上升,而在比例限 度以上接近最大載重,其表面最高溫度僅略上升0.3-0.4°C,隨著應變之增加,試體之表面最 高溫度則隨應變之增大而明顯上升,當試體破壞即載重下降之瞬間,其表面最高溫度上升至 最大。在試驗中表面最高溫度之上升程度依樹種而不同,如櫸木之表面最高溫度上升了14.9° C,而扁柏則上升了7.9°C。 在橫向壓縮試驗中,應力於比例限度下時試體表面最高溫度無明顯上升,而應力於比例 限度以上時試體表面最高溫度則隨應變之增加而增大,但其增大之程度較縱向壓縮者明顯減 小,僅約為1°C且受樹種之影響較不顯著。 |
英文摘要 | The objective of this project was to investigate the feasibility of usinginfrared thermography in nondestructive evaluation of wood defects or failure. The surface temperature of wood specimens of China fir (Cunninghamia lanceolata), Taiwan hinoki (Chamaecyparis taiwanensis), Taiwan incense cedar (Libocedra formosana), Taiwan paulownia (Paulownia taiwaniana), red meranti (Shorea spp.), and Taiwanzelkova (Zelkova serrata) under longitudinal and lateral compression loading was measured with a thermographic device. The relationships between the compression strain and fracture of the specimen, and the temperature rise are discussed. In the longitudinal compression test, the location of the surface temperature rise closely corresponded with the site of fracture of the specimen. The temperature on the surface of a specimen remained almost unchanged below the proportional limit and rose only about 0.3-0.4°C from that time until near the maximum load. An obvious increase in temperature occurred with a further increase in the compression strain accompanied by a decrease in load. The highest temperature was detected at the instant that the specimen failed. The temperature rises observed in this study differed with the species of wood tested; for example, 14.9 and 7.9°C increases were detected for Taiwan zelkova and Taiwan hinoki, respectively. In the test of lateral compression, the temperature rise on the surface of the wood specimen was not significant within the proportional limit but increased significantly with increasing compression strain above the proportional limit. The temperature rises were not significantly affected by the species of wood and were about 1°C which were smaller than those observed in the longitudinal compression test. |
本系統中英文摘要資訊取自各篇刊載內容。