【摘要】 由导流洞改建而成的永久泄洪洞,在堵头末端存在导流洞与泄洪洞交汇的不利情况。结合紫坪铺2#导流洞工程,运用三维非线性有限元方法,重点研究三种工况条件下该区域岩体的变形和稳定性,揭示了开挖过程中不同支护型式以及导流洞封堵后库水对该区域岩体的作用与影响程度。结果表明:导流洞与泄洪洞交汇区域的岩体应重点支护,锚杆的长度应适当加长,有条件时应进行全断面混凝土衬砌。更多还原

【Abstract】 There is adverse spatial stress distribution at the end of the plug of diversion tunnel, which is to be transformed into permanent spillway tunnel. In combination with the 2# Diversion Tunnel Plug of Zipingpu Hydroproject, 3D nonlinear Finite Element Method (FEM) is used to analyze the deformation and stability of surrounding rock in the nearby region under three operation conditions. The action and influence extent that different supporting types and water impoundment exert on during excavation are discussed.It shows that the rock in the intersection between diversion tunnel and spillway tunnel should be supported emphaticslly and the length of anchor should be lengthened properly, the concrete lining is necessary. 更多还原