921地震霧峰、太平地區液化及下陷調查分析

Liquefaction and Settlement in Wufeng and Taiping Counties during Chi-Chi Earthquake

褚炳麟(Bin-Lin Chu) ； 張益銘(Yi-Ming Chang) ； 陳冠閔(Kuan-Min Chen) ； 徐松圻(Sung-Chi Hsu) ； 張錦銘(Chin-Ming Chang)

《地工技術》 77期 (2000/02) Pp. 19-28

https://doi.org/10.30140/SG.200002.0001

摘要

921集集大地震在台中縣內除了造成台中港數個沉箱碼頭因液化而導致地層下陷與滑移外，靠近沿海之清水鎮及大肚鄉亦有液化噴砂災情，且由於此次地震之震央位於台灣中部地區加上強度之大及延時極長，致使連靠近西部麓山帶之霧峰鄉及太平市也發生因液化而導致嚴重災害。本文針對霧峰鄉及太平市液化之範圍及相關災情作一詳細介紹及初步分析。液化除了冒水噴砂外，尚有地層及房屋下陷、傾斜、水平位移，以及側向擴展等現象，主要液化噴砂位置則大多位於河道之兩側，且在河流彎道之沉積側居多。而可能發生液化之深度及及噴砂性質，可由所蒐集到之鑽孔資料及粒徑分析結果得到間接證實。

關鍵字

液化 ； 地震 ； 下陷 ； 側向擴展

並列摘要

Soil liquefaction due to Chi-Chi earthquake was found at Taichung harbor and several counties along the coast in Taichung. As a result of this strong earthquake occurred at the middle of Taiwan and the duration was long enough, the counties, Wufeng and Taiping, next to the western mountain areas also had serious damages due to soil liquefaction. Locations of soil liquefaction and corresponding damages in these two counties are investigated and described in this paper. There are several phenomena associated with soil liquefaction can be observed, they are sand blows, settlement and inclination of ground or buildings, lateral movement and spreading, and flow failure. The major places of sand blows are found to locate close to or beside the rivers, especially the sedimentation side of a river. The possible depths of liquefaction and soil properties are analyzed using collected boring log data and results of grain size distribution of the sand blow.

並列關鍵字

liquefaction ； earthquake ； settlement ； lateral spreading