大跨度地下厂房岩锚梁结构施工过程受力与变形计算和监测分析

重庆乌江彭水水电站地下厂房纵轴线与薄层、陡倾角灰岩、夹软弱页岩层走向呈0°交角布置，岩性自稳时间短、卸荷变形快，对布置在高边墙上的锚梁结构的安全极为不利。针对岩体加载和卸荷过程中的力学性质的本质区别，为分析岩体卸荷规律对布置在洞室高边墙上梁体结构安全的影响，掌控岩锚梁结构的安全度，施工中选取厂房区域的典型地段作为计算剖面，采用有限差分法模拟地下厂房的开挖、加固和岩锚吊车梁的建造及运行状态，重点分析主厂房围岩与支护及岩锚吊车梁的变形及受力状态。通过受力计算分析以指导施工，借助安全监测数据分析，表明梁体结构安全可靠。

Calculation and Monitoring Result Analysis of Stress and Deformation of Rock Anchor Beam of Large Span Underground Power Plant

The angle between the longitudinal axis of the underground power plant of Pengshui Hydropower Station on Wujiang River in Chongqing and the strike of the thin-stratified steep-inclined limestone containing weak shale is 0° and the surrounding rock mass has poor self-support capability and quick unloading deformation,which is extremely unfavorable to the safety of the anchor beam structure installed on the high side walls.The influence of the rock mass unloading on the rock anchor beam structure installed on the high side walls is analyzed on basis of the mechanical behavior of the rock mass during loading and unloading.In order to control the safety of the rock anchor beam of the power plant,the typical sections of the power plant are selected as calculation profile and simulation is made on the excavation and reinforcement of the power plant and on the construction and operation of the rock anchor beam by finite difference method.The deformation and stress of the surrounding rock mass and support structure of the power plant and the deformation and stress of the rock anchor crane beam are analyzed in detail.The calculation and analysis provides guidance to the construction.The monitoring data indicates that the beam structure is safe and reliable.