2023-08-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/673132為了避免斷層錯動災害，房屋與結構物須避開斷層旁一定範圍，然而部分線性構造物例如高速公路、隧道或擋土結構等公共基礎建設，北到南延伸，則無法避免的必需通過斷層帶。傳統剛性混凝土構造物，對地表差異沉陷與角變量具有較低容許值，在斷層錯動作用下，因地表產生劇烈變形而導致剛性結構物受損或倒塌。本研究取以柔克剛的概念，提出以柔性加勁工法減緩斷層錯動災害的構想，以加勁構造物做為跨斷層段之公路路堤與基礎，以減緩斷層錯動引致地表變形之影響，達到減災與防災之目的。 本研究申請書規劃一三年期研究計劃，將利用一系列物理試驗與數值分析探討加勁結構物在斷層錯動作用下之力學行為與設計方法。第一年計畫將進行加勁基礎的砂箱模型試驗、隨增加斷層的錯動量，觀察地表變形特徵，剪裂帶發展，與加勁材受力。並透過改變不同土壤與加勁材參數條件(如土層厚度、加勁材層數、張力強度、勁度、與鋪設長度等)以了解上述參數對減緩斷層錯動引致地表變形之效果。第二年計畫將進行離心機試驗研究，探討不同覆土應力與上部構造物載重對加勁基礎在斷層作用下之影響。第三年將以有限元素法模擬加勁構造物應用於國道4跨車籠埔斷層段之實際案例，探討上部加勁路堤與下部加勁基礎之互制關係。此外透過數值參數分析結果，也將提出最佳化設計方法(如加勁材抗張強度與鋪設長度)，以提供後續加勁構造物抗斷層作用實務設計上參考使用 To avoid surface faulting hazards, the construction of buildings and structures within a site-specific fault setback is restricted by laws. However, linear infrastructures (such as highways, tunnels, and retaining structures) inevitably must cross the areas that may undergo surface fault rupture. Conventional rigid reinforced concrete structures have low tolerance to ground differential settlement and angular distortion. When faulting occurs, the rigid RC structures could be damaged or collapsed due to substantial ground movement and surface rupture. In this proposal, the use of a geosynthetic-reinforced soil (GRS) structure, a ductile and flexible structure, to traverse the surface fault rupture zone is proposed as an effective disaster mitigation measure for surface faulting hazards. The GRS structure consists of a GRS embankment and an underlying GRS foundation. The GRS foundation is adopted to reduce the extent of fault-induced angular distortion to an acceptable level. The GRS embankment is to accommodate the differential settlement at the ground surface and maintain its stability and serviceability. Accordingly, this proposal plans a three-year research project to investigate the performance, reinforcing mechanism, and design methods of GRS structures across a fault. In the first year, a series of model tests will be conducted to study the performance of GRS structures subjected to fault movement, considering various parameters such as foundation soil thickness, reinforcement layer, tensile strength, stiffness, and length. As fault movement increases, the characteristics of ground deformation, propagation of shear rupture, and mobilization of reinforcement tensile force are observed and investigated. This study aims to investigate the effect of the GRS foundation on reducing the fault-induced angular distortion at the ground surface. In the second year, centrifuge tests will be performed to evaluate the effect of soil overburden pressure and surcharge on the performance of the reinforced foundation subjected to fault movement. In the third year, finite element analyses will be performed to simulate a real case in which a GRS structure is constructed as an embankment of Highway No. 4 to crossing the Chelungpu fault. The highlight of the numerical study is to investigate the mutual interaction mechanism between GRS embankment and GRS foundation. Besides, optimal design methods will be developed to determine the reinforcement tensile strength and length against reinforcement breakage and pullout caused by fault movement. Design implications and recommendations based on the results and findings from this research will be proposed to benefit the practical design of GRS structures against fault movement.地工合成材;加勁構造物;斷層錯動災害; 差異沉陷;角變量;減災工法;Geosynthetics; Geosynthetic-reinforced soil structure; Faulting Disaster; Differential settlement; Angular distortion; Disaster Mitigation Techniques