摘要
风火山隧道最突出的技术问题是隧道全部穿越多年冻土、含冰量高,施工的原则是保护冻土、减少人为因素对冻土层的热扰动。针对洞口浅埋段含冰量高、覆盖层薄、热扰敏感性强的特点,研究了相应的施工技术;针对防水、保温结构的施工,提出了无钉法铺设的新工艺;多年冻土隧道施工掌子面保持负温有利于围岩稳定,而支护混凝土要求正温有利于质量的保证,因此采用控温技术来解决温度需求的矛盾;施工爆破对冻土的影响是造成围岩损伤以及爆炸后产生巨大的热能影响冻土的热平衡关系,为减小爆破的影响,采用微振动爆破技术,并采用盐水炮泥封堵炮孔来降温防尘;为了解决冻土隧道湿喷混凝土技术难题,研制了复合型抗冻速凝剂;低温、低压、缺氧使机械效率严重下降,为此研究了合理的机械选型和配套作业线;研究成果确保了风火山隧道的施工质量。
The uppermost technique problem in Fenghuoshan Tunnel is tunnel entirely traversing permafrost. The principle of tunnel construction is protecting permafrost and reducing heat disturbing because of artificial factor. In allusion to specialty of high ice contain, thin soil and high heat sensitivity in tunnel shallow burying segment, relevant construction technologies are studied. According to characteristics of construction of waterproof and insulating, the new laying craftwork of ＂naught nail method＂ is advanced. The negative temperature around the working face of tunnel in permafrost is propitious to surrounding rock stabilization, and positive temperature is propitious to guarantee quality of concrete, so, the technology of temperature control is adopted to solve the conflict of temperature. Influences on permafrost in blasting construction are the damage of the surrounding rock and tremendous heat energy to influence the heat balance of permafrost. To reduce the effects smooth explosion is adopted, and brine mud is applied to block up explosion holes in order to cool and dustproof. To solve the technique problem of wet jet concrete in permafrost tunnel construction, composite fast concreting medicament is developed. Low temperature, low press and lack oxygen make machine efficiency to descend badly, so logical machine choosing model and matching line is studied. Research results ensure construction quality of Fenghuoshan tunnel.
出处
《施工技术》
CAS
北大核心
2008年第10期59-64,107,共7页
Construction Technology
关键词
隧道
青藏铁路
多年冻土
施工技术
tunnel
Qing-zang railway
permafrost
construction technology
