淺層崩塌不安定性評分表之建立-以臺北市為例

Establishment of Score Rating Chart on Failure Potential for Shallow Landslides - A Study Based on Taipei Data

何彥德(Yan-De Ho)

指導教授 ： 劉家男

國立暨南國際大學/科技學院/土木工程學系/碩士(2017年)

摘要

近年隨著經濟發展，都會區向外延伸，山坡地的開發及利用已行之有年，受自然因素影響，邊坡易產生崩塌與地層滑動，危及坡地居民安全，導致民眾生命財產嚴重損失。臺北市政府為有效的進行坡地災害管理，已開始推行轄內自然邊坡風險評估及分級管理工作，針對淺層崩塌、落石、弧形滑動、平面型滑動等四類常見之山坡地地質災害類型進行風險分級管理。北市自然邊坡的風險分級是透過風險評分表進行，考量登錄的潛感邊坡數量多，先以表單中能於室內作業取得資料之因子進行初步篩選作業，將資料區分為是否需進一步關注。邊坡風險評分雖有既定表單，惟評分表之鑑別度尚需加以探討。
本研究探討北市邊坡風險評分中的不安定評分表單之鑑別度，並特別針對初篩使用的表單部分進行探討。本研究的基礎資料為依據表單所需因子萃取所得參數建立的資料庫，鑑別度的評析則透過不安定指數法進行，並輔以假設檢定成果進行判視。研究發現，數個前人研究建議的不安定評分表若未經適度修正無法直接應用於台北市的淺層崩坍潛感邊坡。台北市現行使用的初篩表單鑑別度有限，本研究檢視兩類表單精進修正後之成果。第一類方法為透過專家會議進行表單之修正，共計有兩個修正後之版本，經檢討發現其鑑別別度並無改善。第二類方法為以實際的邊坡資料，檢算相關因子之配分及權重，此方式始能有效提升評分表單之鑑別度。顯見評分鑑別度與實際資料具高度依附性，不安定評分表中因子之分級與權重配分最好經由實際資料來建立，實務上可能先取得邊坡資料庫再發展評分表單為較合理之作業程序。

關鍵字

淺層崩塌 ； 風險評估 ； 風險評分法 ； 不安定指數法

並列摘要

Use of slope land often is needed along with the development of metropolis. Ex-tensive use of slope land increased the potential of slope related disaster, hence it be-comes an important issue for the authority to implement effective means for slope safety management. The Taipei City has implemented an initiative to assess and group registered natural slopes with hazard susceptibility. The aim was to administrate the potential hazardous spots based on the level of landslide risks. Risks of the registered slopes were assessed using a risk scoring method. Since the amount of registered slopes is significant, a first approach was to carry out a first screening based on only portion of the scoring items. Although risk scoring sheet has been adopted, the effec-tive of the assessment approach has not be investigated.
This study investigate the effective of the risk scoring sheet for potential assess-ment. Specifically, items used in the first screening will be the focus of this study. The effective is examined using the multivariate analytic index with additional information from the hypothesis testing. Several preciously proposed instability scoring sheet were examined against the Taipei shallow landslide inventory. It is found that existing scor-ing methods can not be directly applied to slopes in Taipei without further modification. Upon examination, the effective of the instability scoring sheet in use for the Taipei city is limited. Two approaches were considered for improvement of the current scoring sheet. The first approach is to revise the scoring sheet through a panel of experts, and two revised versions were obtained. However, it is shown that no significant important were resulted in these revised version. The other approach is to revise the score alloca-tion and recalculate the weight for each factor based on the inventory data. It is found that a significant improvement can be achieved, and the effectiveness of the scoring sheet is highly related to the slope characteristics. It is recommended that the ap-proach on instability scoring might need to be changed, where the scoring system is developed after acquiring the slope inventory.

並列關鍵字

Shallow Landslides ； Risk Assessment ； Risk Scoring Method ； Multivariate Analytic Method

參考文獻

1. 內政部建築研究所(2008)，既有山坡地住宅社區邊坡擋土設施安全診斷基準之研究，研究報告。

2. 黃慶生、李咸亨(2004)，台北地區天然邊坡快速安全評估系統與指標之研究，國立台灣科技大學營建工程系碩士論文。

3. 許煜煌、林美聆(2002)，以不安定指數法進行地震引致坡地破壞模式分析，國立台灣大學土木工程學研究所碩士論文。

4. 陳昆廷、蔡光榮、王宣惠、林欽川(2008)，多變量不安定指數分析法應用於屏東山區道路邊坡崩塌潛感評估模式之建置研究，中興工程季刊，第100期，pp.65-72。

5. 邱禮理、蔡光榮、陳怡睿(2010)，多變量不安定指數結合GPS/GIS應用於高雄壽山坡地社區邊坡破壞風險評估模式之建置，長榮大學土地管理與開發學系碩士論文。