金門海砂軍事設施存活因素之探討

A Study of Survival Factors of Kinmen Beach Sand Military Facilities

林世強(Shyh-Chyang Lin)

《國立金門技術學院學報》 2期 (2007/02) Pp. 61-72

https://doi.org/10.7057/JNKIT.200702.0061

摘要

近年台灣地區曾因發生嚴重之海砂屋問題，而衍生住宅糾紛與社會問題，然而金門自從民國三十八年至今所興建之建築物與軍事設施皆使用海砂，雖有海砂屋問題但軍事設施中混凝土剝落與鋼筋鏽蝕情形較少，其原因與機理十分值得探討與研究，本文即針對此課題進行深入瞭解，以發掘金門海砂軍事設施存活之主要因素。本研究主要針對金門各軍事碉堡、軍用營舍、防空洞與部份廢棄民房進行混凝土鑽心取樣，所得樣本量測其中性化深度、抗壓強度、氯離子含量等數據，並以此推斷金門海砂屋耐久之機理與因素。根據所獲結果與參考金門工程特性，本研究推論金門海砂軍事設施得以耐久而較少剝落情形之因素，主要為載重單純與鋼筋保護層等二項因素，由於金門並非位於主要地震帶，地震之發生相當稀少，因此結構物載重簡單較無預期外之作用力，且因軍事設施皆為厚實結構，鋼筋保護層厚度充足，混凝土不易產生裂縫，因此而阻斷水氣入侵之路徑使得建築物得以耐久而鋼筋不易鏽蝕，至於其他耐久因素亦於本文中有深入之討論。

關鍵字

海砂屋 ； 混凝土 ； 氯離子 ； 金門

並列摘要

Beach sanded buildings have caused serious social problems in Taiwan. Since 1949 Kinmen has been widely using beach sand on reinforced concrete structures but there has not been severe failure of the buildings, especially military structures. This study is aimed to find out the reasons and mechanism of the durability of beach sanded military structures in Kinmen.To prevent any confrontation from the local residents, the concrete samplings were taken from abandoned military buildings and some civilian houses. The samples were then tested for their depths of carbonated zones, Chloride ions contents and compressive strength.Based on the results of the experiment and the features of concrete construction in Kinmen, it was found that abundant concrete cover and lack of large loadings in Kinmen are two major causes to make Kinmen's beach sanded military structures durable. Without earthquakes and other irregular loadings, micro-cracks in non-high rise buildings wouldn't extend to provide routs for moisture and oxygen to get into concrete. This mechanism would therefore prevent beach sanded concrete from spalling or even structural failure.

並列關鍵字

Beach sanded building ； Concrete ； Chloride ； Kinmen