基于增量法的隧道洞口边坡微型钢管桩-锚杆支护效果分析  

Analysis of the Support Effect of Micro Steel Pipe Pile-Anchor Bolt at Tunnel Portal Slope Based on the Incremental Method

作　　者：许晓静 宋战平[1,2,3] 田小旭 丁立波 孙引浩 赵俊波 XU Xiaojing;SONG Zhanping;TIAN Xiaoxu;DING Libo;SUN Yinhao;ZHAO Junbo(School of Civil Engineering,Xi'an University of Architecture and Technology,Xi'an 710005;Shaanxi Key Laboratory ofGeotechnical and Underground Space Engineering,Xi'an 710005;Research Institute of Tunnel and Underground Structure ngineering,Xi'an University of Architecture and Technology,Xi'an 710005;China Road and Bridge Corporation,Beijing 100011;The First Engineering Co.,Ltd.,China Railway 20th Bureau Group Co.,Ltd.,Suzhou 215151)

机构地区：[1]西安建筑科技大学土木工程学院,西安710005 [2]陕西省岩土与地下空间工程重点实验室,西安710005 [3]西安建筑科技大学隧道及地下结构工程研究所,西安710005 [4]中国路桥工程有限责任公司,北京100011 [5]中铁二十局集团第一工程有限公司,苏州215151

出　　处：《现代隧道技术》2024年第6期118-128,共11页Modern Tunnelling Technology

基　　金：国家自然科学基金资助项目(52178393);陕西省创新能力支持计划-创新团队(2020TD-005).

摘　　要：微型钢管桩-锚杆联合支护具有施工方便、结构简单、布置灵活等优点,在滑坡治理以及基坑防护工程中得到广泛应用,但在隧道洞口边坡中的应用较少。为研究微型钢管桩-锚杆支护在隧道洞口边坡的支护效果,依托格鲁吉亚1号隧道项目,采用增量法对微型钢管桩-锚杆的支护效果进行数值模拟研究并结合现场监测数据进行分析。结果表明:采用考虑施工过程的增量法对微型钢管桩-锚杆支护体系进行模拟更加合理;在破桩施工后,边坡最大位移为10.20 mm,锚杆最大轴力为339.42 kN,小于锚杆设计轴力420.14 kN,所选特征桩的侧向最大位移为9.90 mm,最大弯矩为31.26 k N·m,低于弯矩设计值84.80 kN·m;边坡竖向位移的实际监测结果与数值模拟结果均显示其呈现“V”形分布且二者数据较吻合;左、右隧道拱顶沉降分别为11.11 mm、8.01 mm,水平位移分别为2.33 mm、1.30 mm。微型钢管桩-锚杆支护体系已成功运用于格鲁吉亚1号隧道项目,保证了隧道洞口段施工的安全。The combined support system of micro steel pipe pile and anchor bolt,due to its advantages such as con-venient construction,simple structure,and flexible layout,is widely used in landslide remediation and foundation pit protection projects,but its application in tunnel portal slopes is less common.Based on the Georgia No.1 Tunnel project,the incremental method is used to conduct a numerical simulation study of the support effect of the micro steel pipe pile-anchor bolt system at tunnel portal slopes,and the simulation results are analyzed in conjunction with field monitoring data.The research results show that the incremental method considering the construction pro-cess is more reasonable for simulating the micro steel pipe pile-anchor bolt support system.After the pile breaking construction,the maximum displacement of the slope is 10.20 mm,the maximum axial force of the anchor bolt is 339.42 kN,which is less than the design axial force of the anchor bolt of 420.14 kN.The maximum lateral displace-ment of the selected characteristic pile is 9.90 mm,and the maximum bending moment is 31.26 kN·m,which is lower than the design bending moment value of 84.80 kN·m.The actual monitoring results of the vertical displacement of the slope and the numerical simulation results both show a"V"shaped distribution and the data are consistent.The crown settlements of the left and right tunnels are 11.11 mm and 8.01 mm,respectively,and the horizontal displace-ments are 2.33 mm and 1.30 mm,respectively.The micro steel pipe pile-anchor bolt support system has been suc-cessfully applied to the Georgia No.1 Tunnel project,ensuring the construction safety of the tunnel portal section.

关 键 词：隧道工程 增量法 微型钢管桩-锚杆 隧道洞口边坡 支护效果 

分 类 号：U455.7[建筑科学—桥梁与隧道工程]