吊橋檢測與安全評估之研究

吊橋(Suspension Bridges)造型優美、節省材料，尤其適用於施工不便又需大跨度的山區;相對於混凝土橋，其開挖面積少、工期短、經費省又少破壞生態，然而大部份吊橋並非屬公路系統，目前尚未納入「臺灣地區橋梁管理資訊系統」(Taiwan Bridge Management Systems,TBMS)中，因此國內吊橋維護管理至今尚無一定的制度及標準，也因為如此，這些吊橋隨著時光的流逝，尤其是缺乏長期必要監測和相應的養護情況下，已陸續出現許多損傷案例，甚至無示警斷裂。由於吊橋沒明確專責的管理單位，因此維護管理的權責劃分，存在極大的模糊地帶。但是行走吊橋的居民或遊客的生命安全卻不該因為權責不清而有所減損。桃園縣復興鄉彌榮吊橋為日治時期的吊橋，竣工時間已不可考，橋長約170m，為三光地區居民通行要道(機車及人行)，惟因年久失修，近年發現多處構件疑有損傷，復興鄉公所為確保居民甚或觀光旅客通行的安全，並能讓這座與在地族人有著濃郁歷史記憶與情感的老吊橋再現新生命，故辦理本吊橋檢測。本研究針對如何建立吊橋基本資料及吊橋檢測資料，並進一步討論吊橋安全評估所必須的儀器檢測項目，這些項目包含:混凝土強度測試錘(Schmidt Hammer)、應力波(Stress Wave)、纜索硬度(Cable Hardness)、三維雷射掃描(3D Laser Scanning)等技術。期能利用有限經費，提供吊橋安全與否的足夠訊息。本文雖只針對單一吊橋進行討論，但相信檢測方法與結果討論，亦適用於其他同類型吊橋。關鍵字:吊橋基本資料、吊橋檢測資料、衝錘、纜索硬度、三維掃描

關鍵字

吊橋基本資料；吊橋檢測資料；衝錘；纜索硬度；三維掃描

並列摘要

Suspension bridges of cable sway bridges are elegant and resource saving especially for inaccessible and mountainous roads. Excavation areas are small with short construction durations, requires minimal funding and has a relatively smaller ecological impact. However, most suspension bridges are not classes as part of the roadway networks and are not yet included in the Taiwan Bridge Management Information System (TBMS). Domestically, no maintenance standards exist for suspension bridge maintenance. Due to this, damages without warning fractures have been identified due to the absence of long-term monitoring. There are no explicit management units for suspension bridges and as such public safety is jeopardized due to a lack of management and degradation. In Fuxing Township of the Taoyuan County, the Mi-Rong Suspension Bridge was constructed in the Japanese Colonial period. The data of completion of the bridge is no longer traceable. The bridge spans for 170 meters and severs as a pedestrian and motorized scooters crossing for the citizens of the San Guang area. Despite the many years of disrepair and suspected damage to the bridge, the city council has reassured the citizens in its usage for residential and tourist traffic. A new phase of testing was initiated due to the rich history and background of the suspension bridge. Keywords: suspension bridge basic data, suspension bridge inspection data, rope hardness, three dimensional scanning.