DSpace community: 土木工程研究所

以離散元素法探討岩坡崩塌能量與臨界斜交角

title: 以離散元素法探討岩坡崩塌能量與臨界斜交角 abstract: 岩坡穩定性受岩體不連續面位態及工程配置角顯著影響，其中坡面傾向（??s）與不連續面傾向（????）之交角，又稱斜交角（|???? ? ??s|, oblique angle）為控制岩坡穩定性與破壞模式轉換之關鍵參數。本文採用PFC3D（Particle Flow Code in Three Dimensions）離散元素法（Discrete Element Method, DEM），建立含單一不連續面之合成岩坡模型，模擬不同斜交角（|???? ? ??s|）與岩坡條件下的崩塌行為，並以崩塌能量為量化指標，探討摩擦角（?j）、坡角（βs）、坡高（H）及不連續面傾角（βj）對崩塌能量與臨界斜交角的影響。模型涵蓋順向坡至逆向坡之完整斜交角範圍，並輔以極限平衡法 RocTopple 進行比對分析，以驗證破壞趨勢之合理性。研究結果顯示：（1）本文依據 PFC3D 模擬結果，建立平面破壞崩塌能量與臨界斜交角之連續函數，得以評估破壞模態轉換與崩塌能量。（2）平面破壞不利因子包含低斜交角、高坡角、高坡高、中等不連續面傾角及低摩擦角；傾覆破壞則以高斜交角、高坡角、高坡高、高不連續面傾角及低摩擦角為主要不利因子，當多項不利因子同時存在時，傾覆破壞崩塌能量將顯著上升，其潛在崩塌規模不亞於平面破壞。（3）在一般岩坡條件下，平面破壞臨界斜交角（γ_(cr,p)）約為 20?，與工程實務經驗及《水土保持技術規範》之順向坡定義相符；當岩坡處於多重不利條件時，臨界斜交角可能提升至約 40?。（4）本文依據 PFC3D 模擬結果，提出傾覆破壞臨界斜交角（γ_(cr,t)）判別式，並驗證其可視為既有現地調查經驗式形式。整體而言，本文之模擬結果顯示斜交角對崩塌能量與破壞模式具有關鍵控制作用，其趨勢與 SMR 位態評分調整一致，並進一步指出既有岩坡分類系統未充分納入摩擦角與坡高等影響因子之侷限性，顯示數值模擬方法於岩坡穩定性評估與工程應用上具有重要價值。關鍵字：離散元素法、異向性岩體、崩塌能量、臨界斜交角、連續函數 ;Rock slope stability is strongly influenced by the orientation of rock mass discontinuities and engineering configuration angles. Among these factors, the angle between the slope face dip direction (??s) and the discontinuity dip direction (????), referred to as the oblique angle (|???? ? ??s|), is a key parameter governing slope stability and the transition of failure modes. In this study, the discrete element method (DEM) implemented in PFC3D (Particle Flow Code in Three Dimensions) is employed to construct three-dimensional synthetic rock slope models containing a single discontinuity. Slope failure behaviors under different oblique angles and slope conditions are simulated, and collapse energy is adopted as a quantitative indicator to investigate the effects of discontinuity friction angle (??), slope angle (β?), slope height (H), and discontinuity dip angle (β?) on collapse energy and critical oblique angles. The models cover the full range of oblique angles from dip slopes to anti-dip slopes, and limit equilibrium analyses using RocTopple are conducted for comparison to verify the rationality of the observed failure trends. The results indicate that: (1) based on PFC3D simulation outcomes, continuous functions describing collapse energy and critical oblique angles for plane failure are established, enabling the evaluation of failure mode transitions and collapse energy levels; (2) unfavorable factors for plane failure include low oblique angles, high slope angles, large slope heights, intermediate discontinuity dip angles, and low friction angles, whereas toppling failure is primarily associated with high oblique angles, high slope angles, large slope heights, steep discontinuity dip angles, and low friction angles. When multiple unfavorable factors coexist, the collapse energy associated with toppling failure increases significantly, and the potential collapse scale is comparable to that of plane failure; (3) under general slope conditions, the critical oblique angle for plane failure (γ_(cr,p)) is approximately 20?, which is consistent with engineering practice and the definition of dip slopes in the Soil and Water Conservation Technical Regulations. When multiple adverse conditions are present, the critical oblique angle may increase to approximately 40?; (4) using PFC3D simulation results, a discriminant equation for the critical oblique angle of toppling failure (γ_(cr,t)) is proposed and verified to be a generalized form of existing empirical relationships derived from field investigations. Overall, the simulation results demonstrate that the oblique angle plays a critical controlling role in collapse energy and failure mode development. The observed trends are consistent with the orientation adjustment logic adopted in the Slope Mass Rating (SMR) system. Furthermore, this study highlights the limitations of existing rock slope classification systems, which do not explicitly incorporate friction angles and slope height, and underscores the importance of numerical simulation as a complementary tool for rock slope stability assessment and engineering applications. Keywords: discrete element method; anisotropic rock mass; collapse energy; critical oblique angle; continuous equation.

機場護送員人力規劃暨彈性排班最佳化之研究

title: 機場護送員人力規劃暨彈性排班最佳化之研究 abstract: 航空產業疫情期間經歷長期低迷，許多機場被迫縮減營運規模，而隨著全球疫情和緩與航空產業復甦，各國面臨旅客流量快速攀升趨勢，其中協助行動不便旅客於機場順利完成搭機流程，機場護送員扮演重要角色。實務上，現今傳統為人工調度方式，缺乏整體規劃，容易導致資源浪費或服務品質下降，造成旅客等待時間過長，以及機場服務品質下降等問題。因此，如何靈活且有效調度護送員，為機場決策者需要面臨與解決之問題。本研究結合時空網路與數學規劃方法，於滿足實務限制條件下，以最小化總人力成本為目標，提出彈性排班策略，構建機場護送員人力規劃模式，同時發展流量分解方法以公平指派任務。鑑於求解問題規模龐大，難以於合理時間內利用數學規劃軟體求出最佳解，故本研究採用 C++程式語言及 CPLEX 數學求解軟體，配合鬆弛固定演算法概念設計三階段啟發式方法以有效求解。最後，針對不同參數條件下進行敏感度分析與方案分析，結果顯示本研究發展之模式與演算法皆具成效良好。期望本研究能解決實務人力規劃問題，協助機場決策者做出抉擇，並將研究結果供學術界參考。;The aviation industry experienced a prolonged downturn during the COVID-19 pandemic, forcing many airports to scale down their operations. As the global pandemic subsides and the aviation sector gradually recovers, countries are now facing a surge in passenger traffic. Among the various operational needs, escort staff play a crucial role in assisting passengers with reduced mobility(PRMs) to complete the airport boarding process smoothly. In practice, current escort staff scheduling primarily relies on manual dispatching, lacking systematic planning. This often leads to inefficient resource allocation, increased passenger waiting times, and a decline in overall service quality. To address these challenges, this study integrates time-space network modeling with mathematical programming techniques to develop a flexible escort staff scheduling strategy under realistic operational constraints, aiming to minimize total labor costs. A flow decomposition approach is proposed to ensure fair task assignment among staff. Given the large-scale nature of the problem, obtaining optimal solutions through exact mathematical programming within a reasonable time frame is difficult. Therefore, a three- stage heuristic method based on the Relax-and-Fix algorithm is designed and implemented using C++ and solved with CPLEX. Sensitivity and scenario analyses are conducted under various parameter settings, and the results demonstrate the effectiveness of both the proposed model and solution algorithm. This study aims to support airport decision-makers in resolving practical manpower planning challenges and to contribute valuable insights for future academic research.

以耦合數值模型探討岩坡塊體運移能量與被動式整治工程之力學反應

title: 以耦合數值模型探討岩坡塊體運移能量與被動式整治工程之力學反應 abstract: 本研究以數值耦合模型以及能量觀點，探討逆向楔形岩坡受弱面性質影響引致破壞時，塊體運移過程與崩落撞擊攔石柵之受力情況。現地楔形岩坡常由多組弱面切割，因外在因素導致塊體運移崩落，而不同弱面參數會導致塊體崩落率與運移崩落各類能量比例不同，此外，本研究亦透過攔石柵之變形情況與應力分佈位置，討論最佳之工程整治策略。本研究以經離心模型驗證之數值模型探討楔形岩坡在不同弱面參數與重力場影響下，塊體崩落機制與能量變化之關係。由於各模型坡體體積有所差異，因此本研究亦以單位體積能量進行模型間之比較，就崩落機制而言，交線傾伏角為控制塊體崩落機制之主因，當交線傾伏角較小，塊體多以滑動的形式崩落，當交線傾伏角較大，塊體多以翻倒碰撞的形式崩落。就能量觀點而言，交線傾伏角對模型能量變化之影響較為顯著，位能會在短時間內降低。在節理間距減半的情境下，因塊體接觸頻繁，彈性接觸能佔比較多。在高重力場下，塊體總能量則明顯變大，且崩落事件多使動能在不同時間點皆有變化；塊體的破碎程度與交線傾伏角為影響塊體在攔石柵前堆積狀況之主因，同時也影響防護網之受力位置與立柱之拉壓應力分佈，在高重力場下攔石柵所受之應力明顯較大且分佈範圍也較廣。最後，本研究以台2線83K一處倒懸岩坡現地條件下進行模擬，觀察塊體運移堆積之能量變化與攔石柵所受之應力，並對其整治策略進行建議，研究結果指出，此處邊坡於極限狀況下，初始運動塊體以位能轉換為動能，但塊體開始堆積碰撞後，位能主要轉為碰撞之彈性能、摩擦能，而碰撞消耗之阻尼能則為最小。 ;In this study uses numerical modeling to investigate the impact forces acting on rockfall barriers caused by block failures from wedged rock slopes along weak planes. The analysis focuses on block barrier interactions, including block overtopping behavior and stress distribution within the barrier system, to evaluate effective mitigation strategies. In natural slopes, wedge failures are commonly induced by multiple discontinuity sets, and variations in weak plane characteristics significantly affect block release likelihood and rockfall energy. This study uses a numerical model validated by a centrifugal model to explore the relationship between the block collapse mechanism and energy change of a wedge slope under the influence of different weak planes parameters and gravity fields. In this study, energy values are normalized by volume energy density to enable comparisons among different models. Regarding the collapse mechanism, the plunge angle is the primary factor controlling the collapse mechanism. When the intersection line plunge angle is small, the blocks tend to collapse by sliding; when the plunge angle is large, the blocks tend to collapse by overturning and colliding. From the energy perspective, the plunge angle plays a crucial role in energy changes, leading to rapid loss of potential energy. Reduced joint spacing increases elastic contact energy due to frequent block collisions. The higher gravitational field significantly increases the total energy, and multiple landslide events cause kinetic energy to vary at different times. Finally, this study conducted a field simulation at the 83K section of Provincial Highway No. 2. The results show that, under extreme conditions, the potential energy of the initially moving blocks is first converted into kinetic energy. After block collisions and accumulation, potential energy is mainly converted into collision energy and frictional energy, while the damping energy dissipated during the collision is minimal.

以數值耦合模型探討隧道與管線受逆斷層錯動之變形與力學反應

title: 以數值耦合模型探討隧道與管線受逆斷層錯動之變形與力學反應 abstract: 本研究主要探討線形地中結構物，如隧道或維生管線受逆斷層錯動時產成的管土互制行為，並整合機率式斷層位移，據以評估適當的工程對策，以保護位於斷層錯動潛勢區中的地中結構物。本研究利用離散元素法軟體PFC3D與有限元素法軟體FLAC3D進行耦合模擬，模擬隧道與維生管線於逆斷層錯動時的力學反應，包括維生管線於覆土層中，經斷層錯動所受張、壓應力破壞之情形，以及隧道對覆土層剪裂帶發展的影響，數值模擬結果與既有離心機實驗(Baziar et al., 2014)進行比對驗證。隨後，延伸分析不同斷層傾角及隧道與斷層走向交角對結構物的影響，識別出造成損壞最嚴重的情境，並引入既有工程對策進行分析。研究結果指出高傾角逆斷層錯動相比低傾角錯動，對線形地中構造物會造成更高風險。當斷層與隧道軸向平行時且位於斷層剪裂帶中時，隧道會有最嚴重的受力破壞。斜交隧道受力略小於正交隧道，但正交隧道的應力集中處更好掌握，應力方向也比較單純，有利於工程對策的設計。以高傾角斷層走向與隧道軸向平行的模型設定，比較純輸水鋼管與使用工程對策保護的複合地中構造物之變形與力學反應，發現混凝土隧道與CLSM對於輸水管線之保護效果顯著。本研究亦設計全尺寸現地模型，並引入「大安溪大甲溪聯通管計畫」的現地參數與工程設計，運用 CLSM回填材、SPF鋼管可以形成明顯的弱帶，將變形量集中於設計區域內，有助於維持聯通管計畫的整體輸水能力，並提升輸水鋼管之服務年限與服務性能。;Fault rupture poses a significant hazard to geotechnical structures located near fault zones. However, it is often challenging to completely avoid fault displacement zones during the alignment planning of geotechnical infrastructures such as tunnels and pipelines. Therefore, this study aims to investigate the soil-pipeline interaction behavior subjected to reverse faulting and to evaluate appropriate engineering countermeasures to protect critical geotechnical infrastructures located within fault-prone areas. This research utilizes a coupled modeling approach by PFC3D with FLAC3D to simulate the mechanical response of tunnels and pipelines under reverse fault ruptures. The numerical results are validated against existing centrifuge test data (Baziar et al., 2014). Following validation, the study explores the effects of varying fault dip angles and the intersection angles between tunnel alignment and fault strike to identify the most critical scenarios. The most severe structural damage occurs when the tunnel is axially aligned with the fault and located within the fault shear zone. While obliquely crossing tunnels experience slightly lower stresses than orthogonally crossing ones, the latter allows for more predictable stress concentration zones and simpler stress directions, which are advantageous for designing mitigation strategies. Finally, A full-scale field model is developed based on a currently ongoing construction project. By incorporating CLSM and SPF pipes, a deliberately designed weak zone is intoduced to concentrate deformations within a targeted region. This strategy effectively preserves the water conveyance capacity of the interconnection pipeline system and significantly enhance both the service life and performance reliability of the infrastructure.