以經驗方法評估潛盾隧道施工引致之地表沉陷

Abstract

本研究之第一部份是蒐集國內外潛盾隧道施工沉陷監測資料進行分析整理，建議於不同土層內，不同型式、不同直徑潛盾機，於不同深度下開挖，所引致隧道中心線上方之地表最大沈陷量(Smax)。第二部份則是根據本研究所提出地表最大沉陷量之範圍，以此結果配合Peck（1969）之沉陷槽寬度參數（i），以常態分佈曲線更合理的預估單隧道施工造成之地表沉陷槽。關於左右平行雙隧道施工引致之地表沉陷，若雙隧道間之距離夠遠，本研究提出之經驗方法亦可以用來評估平行雙隧道施工引致之地表長期沉陷槽。本研究最後依據台北捷運中和線之地表沉陷監測資料，嘗試以經驗方法估算其潛盾隧道開挖造成之地表沉陷。分析結果顯示監測沉陷值大都落在預測範圍內，顯示本論文所建議經驗方法之可用性。

Base on field monitoring data, this study investigates the range of the maximum surface settlements by statistics of the field data. According to the shield machine used and soils excavated, the cases have been divided into six different types: EPB in cohesive soils, EPB in cohesionless soils, open shield in cohesive soils, open shield in cohesionless soils, slurry shield in cohesive soils and slurry shield in cohesionless soils. Combining settlement-trough width parameter " i " suggested by Peck in 1969, a more reasonable empirical method is proposed to predict the ground surface settlement troughs. In this method, the effects of tunnel depths and tunnel diameters on settlement are included. In the last part, the construction of shield tunnels for Chungho Line of Taipei Rapid Transit Systems (TRTS) is discussed. The empirical method is used and compared with the monitored settlement data. The estimated troughs are in fairly good and agreement with field monitored data for tunnels at different depths.