交通/水工隧道中基于预应力锚固系统的及时主动支护理念及其技术实现  

Timely-active Support Theory and Its Application in Transportation/Hydraulic Tunnels Based on Pre-stressed Anchorage System

作　　者：汪波[1] 喻炜 刘锦超 王振宇[1] 徐建强 吴德兴 WANG Bo;YU Wei;LIU Jin-chao;WANG Zhen-yu;XU Jian-qiang;WU De-xing(Southwest Jiaotong University,MOE Key Laboratory of Transportation Tunnel Engineering,Chengdu 610031,Sichuan,China;East China Investigation and Design Institute Under CHECC,Hangzhou 310014,Zhejiang,China;Zhejiang Provincial Institute of Communications Planning,Design&Research Co.Ltd.,Hangzhou 310006,Zhejiang,China)

机构地区：[1]西南交通大学交通隧道工程教育部重点实验室,四川成都610031 [2]中国电建集团华东勘测设计研究院有限公司,浙江杭州310014 [3]浙江省交通规划设计研究院有限公司,浙江杭州310006

出　　处：《中国公路学报》2020年第12期118-129,共12页China Journal of Highway and Transport

基　　金：四川省重点研发项目(2019YFG0001);国家自然科学基金项目(51878571);甘肃省科技计划项目(19ZD2GA005);中国国铁集团科技研究开发计划项目(P2019G038-4)。

摘　　要：为实现新奥法充分调动围岩承载能力这一核心理念,能够实现及时主动支护的锚固体系是关键。基于此,从及时主动支护技术的内涵及作用机理分析入手,对预应力构件及早施加主动支护阻力,以增强岩体自承载能力,从而实现变形控制的作用机理进行了阐述;以滇中引水工程楚雄段柳家村隧洞为依托,对比分析了主、被动支护作用效应,验证了主动支护对于围岩位移及塑性区发展的有效控制;针对具有长期服役要求的交通/水工隧道,结合不同岩体状况,提出为实现及时主动支护,在一般岩体中建议采用端头机械锚固+自由段水泥砂浆锚固的锚固形式,在软弱破碎岩体中则建议采用端头树脂锚固+自由段水泥砂浆锚固的锚固形式。上述2种锚固形式一方面通过临时性端锚及早施加预应力以实现及时主动支护,另一方面在洞室变形基本稳定后进行后期注浆,在有效防止预应力损失的同时,使得锚固体系具有良好的耐久性,为基于预应力锚固体系的及时主动支护理念在交通/水工隧道工程中的成功应用奠定了坚实的基础。To actualize the key theory and fully utilize the self-bearing capacity of the surrounding rock in the New Austrian Tunneling Method,the anchorage support system,a type of timelyactive support,is designated as the core in this study.Therefore,the contents and mechanism of timely-active support technology are analyzed first.The deformation is excellently controlled with the pre-tensioned components by applying the support force swiftly to strengthen the rock.The effects between the active and passive supports are compared based on the conditions of the Liujiacun Tunnel of the water diversion engineering in Chuxiong,central Yunnan.It has been proven that the deformation and plastic zone development of surrounding rock can be optimally controlled using active support.To realize timely-active support while considering the properties of the rocks in the long-term service transportation and hydraulic tunnels,the anchorage type of resin head with the posterior cement mortar segment in normal rock as well as that of mechanical head in soft fractured rock is proposed.On one hand,the temporary anchoring head realizes the timely-active support.On the other hand,the posterior cement mortar is injected after the deformation becomes stable.This method does not only prevent pre-stress loss but also creates a cement mortar with great durability.The proposed anchorage types make it possible to apply the timely-active support theory in long-term underground engineering services.

关 键 词：隧道工程 交通/水工隧道 及时主动支护 预应力锚固体系 锚固形式 

分 类 号：U45[建筑科学—桥梁与隧道工程]