旋喷桩加固技术在某隧道风积砂地层中的应用  

Application of Jet Grouting Reinforcement to Tunneling in an Aeolian Sand Stratum

作　　者：徐智[1] 胡蔓宁[1] 

机构地区：[1]中交第一公路勘察设计研究院有限公司,西安710075

出　　处：《现代隧道技术》2013年第3期158-162,共5页Modern Tunnelling Technology

摘　　要：风积砂具有结构松散、粘聚力小、抗剪强度低等特点,在外力作用下极易松散变形。文章介绍了在某隧道风积砂地层中,采用常规长管棚注浆加固方案存在掌子面漏砂严重、变形难以控制以及施工进度缓慢等不足;提出通过在地表采用竖直旋喷桩加固洞周围岩、在洞内采用水平旋喷桩进行超前支护,能防止漏砂、有效控制变形并提高施工进度。现场监控量测结果表明,采用长管棚注浆加固方案引起的隧道拱顶沉降值、周边收敛值分别是采用旋喷桩加固方案引起拱顶沉降值、周边收敛值的6.5倍和3.6倍;两方案工期相比,前者是后者的1.9倍。这说明采用旋喷桩加固风积砂,对控制隧道变形、提高施工工期,优势是非常明显的。Aeolian sand features a loose structure as well as low cohesive force and shear strength, which means that it is apt to become loose and deformed under external force. This paper presents the deficiencies of conventional long pipe roof grouting reinforcement for tunneling in aeolian sand, including serious sand leakage, diffieuhy controlling the deformation at the tunnel face, and a long construction period. These deficiencies may be overcome by using a ver- tical jet grouting pile on the ground for surrounding rock reinforcement and a horizontal jet grouting pile in the tunnel for advanced support. Site monitoring and measurements show that crown settlement and peripheral convergence in- duced by long pipe roof grouting reinforcement are 6.5 times and 3.6 times that induced by jet grouting pile reinforce- ment respectively. Furthermore, the construction duration with the pipe roof scheme is 1.9 times longer than that with jet grouting

关 键 词：隧道 风积砂 旋喷桩 应用 

分 类 号：U455.49[建筑科学—桥梁与隧道工程]