摘要
为深入研究穿越土-岩复合地层的盾构隧道纵向地震响应,本文基于甬舟铁路金塘海底隧道跨海段盾构区间工程,构建了穿越土-岩交界地层盾构隧道的三维精细数值模型,并通过振动台试验进行了验证,计算了不同土-岩交界面夹角及刚度比对隧道纵向地震响应的影响。研究表明:(1)土-岩交界面显著影响隧道纵向地震响应,尤其在交界面和软土侧。(2)当土-岩交界面夹角从30°增大到90°时,隧道的变形和内力减小,但超过75°时软土侧负弯矩会增大,建议隧道穿越土-岩交界面的夹角选择在45°~75°之间。(3)土-岩刚度差异过大时,隧道会有过大的变形和内力,建议刚度比在1∶5~1∶20之间。(4)当盾构隧道穿越土-岩交界地层时,应将交界处作为隧道纵向抗震设计的关键控制截面,且在交界面前后10~20环管片处采取减震措施。
In orderto study the longitudinal seismic response of shield tunnel crossing soil-rock composite strata,the refined 3D numerical model based on the Yongzhou Railway Jintang submarine tunnel project is developed.Validated by shake table tests,the model analyzes the effects of different soil-rock interface angles and stiffness ratios on seismic response.Key findings include:(1)The interface significantly impacts seismic response,especially at the interface and soft soil side.(2)As the angle increases from 30°to 90°,tunnel deformation and internal forces decrease.But beyond 75°,negative bending moments on the soft soil side rise.Thus,an angle between 45°and 75°is recommended.(3)Large stiffness differences cause excessive deformation and forces,with a stiffness ratio of 1∶5 to 1∶20 advised.(4)When the shield tunnel crosses the soil-rock interface,the interface should be a key control section in seismic design,with mitigation measures applied within 10-20 lining rings around the interface.
作者
杨绍毅
封坤
沐海星
薛皓匀
郭文琦
曹翔鹏
Yang Shaoyi;Feng Kun;Mu Haixing;Xue Haoyun;Guo Wenqi;Cao Xiangpeng(Key Laboratory of Transporta-tion Tunnel Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China;China Railway Siyuan Survey and Design Institute Group Co.,Ltd.,Wuhan 430063,China)
出处
《土木工程学报》
CSCD
北大核心
2024年第S2期133-141,共9页
China Civil Engineering Journal
基金
中国国家铁路集团有限公司系统性重大项目(P2022G054)
国家自然科学基金(52078430)。
关键词
盾构隧道
土-岩交界地层
管片衬砌
纵向地震响应
数值模拟
shield tunnel
soil-rock boundary strata
segment lining
longitudinal seismic response
numerical simulation
