臺灣博碩士論文加值系統

隧道交叉段具有複雜的三向度行為，以往只使用二維的數值分析，配合經驗及放大安全係數來探討實際屬於三向度的隧道交叉段行為，其實際狀況並不能全盤瞭解。本研究利用三向度的數值分析來模擬隧道交叉段開挖對主隧道的影響，分別探討聯絡道與主隧道為斜交45°及正交兩種型式交叉段，在不同岩體評分及不同側向壓力係數K下，分析交叉段力學行為之應力應變行為及影響範圍，並相互比較。本研究主隧道斷面為三心圓，隧道寬為17m，聯絡道斷面為馬蹄形，寬度為7m，主隧道與聯絡道以行車高程相同之方式交叉。研究發現破孔處之主隧道側壁應力變化大於未破孔之頂拱、仰拱應力變化，破孔處有很明顯的應力集中現象，同時在斜交交叉段，銳角側大於鈍角側，岩盤愈差應力影響範圍愈大。比較兩種不同隧道交叉型式中發現，斜交對主隧道影響大於正交，在地質愈差時愈明顯。

The behavior of cross connections between tunnel tubes should be three-dimensional, and is not suitable using two-dimensional numerical simulation, no matter how empirical judge or safety factor includes. Three-dimensional analysis of under different RMR and lateral stress ratio K. The cross section shape of main tunnel is triple-circular-arcs for main tunnel, and horse-shoe for cross connections. The widths of the main tunnel and cross connection are 17 and 7 meters respectively, and the circular centers The research results show that stress concentration is significant around the penetration region of cross connections, and the concentration is higher in the acute side than obtuse side for inclined cross connections. The influential region of cross connections depends on the rock condition, the region increases if RMR decreases, the tendency is significant if cross connections are located on poor rock.