摘要
新意法是一种以控制隧道超前核心土变形为核心理念的软岩隧道设计、施工指导方法。结合桃树坪大断面软岩隧道工程,通过数值模型模拟隧道周边超前支护、掌子面前方围岩加固、拱脚补强3种隧道加固方式,得出大断面软岩隧道施工中合理的新意法施工加固参数,并对比桃树坪隧道实际施工参数,结合监测数据对其采用的新意法隧道加固参数进行评价与分析。结果表明,单纯进行隧道拱部超前支护很难发挥其梁效应与拱效应,控制掌子面的稳定与位移;软岩隧道的掌子面需用长超前支护进行加固,但加固密度要达到一定数值后加固效果才会显著;相比掌子面锚杆,掌子面旋喷桩可以与超前核心土形成强度更高的复合体,显著地提高超前核心土的承载能力;锁脚旋喷桩可以比锁脚锚杆获得更好的临时封闭成环效果。
With the core idea of controlling the advance core deformation around the tunnel, ADECO-RS approach is an instructional design and construction method for soft-rock tunnels. Combining with the actual construction conditions of a soft-rock tunnel project with large section （ Taoshuping tunnel）, the reasonable reinforcement parameters of soft-rock tunnel with large section based on ADECO-RS approach are obtained by numerical simulation of pre-support around tunnel, reinforcement of the core rock at tunnel face and strengthening of arch springing. The reinforcement parameters of Taoshuping tunnel are evaluated and analyzed with the monitoring data and comparison between the monitoring data and the simulation result. The results show that （1） it is difficult to make the pre-support play the role as the beam and arch to control the stability and deformation of the tunnel face if only reinforcing the rock around the tunnel arch; （2） the reinforcement of soft-rock tunnel face requires long advanced support and the effect will be significant after the reinforcement density reaches a certain value; （3） compared to the tunnel face anchor bolts, the horizontal churning piles and the advance core soil can be mixed together and turn into a complex with higher strength which can significantly increase the bearing capacity of the core soil; （4） feet-lock churning piles can achieve better closed-structure result than the feet-lock bolts .
出处
《公路交通科技》
CAS
CSCD
北大核心
2013年第3期105-110,共6页
Journal of Highway and Transportation Research and Development
基金
国家自然科学基金项目(50978016)
关键词
隧道工程
软岩隧道
数值模拟
新意法
加固参数
水平旋喷桩
tunnel engineering
soft-rock tunnel
numerical simulation
ADECO-RS approach
reinforcement parameter
horizontal chemical churning pile
