摘要
基于新建隧道群下穿福州绕城公路东南段董奉山既有隧道工程,运用三维有限元研究新建隧道群施工对既有隧道的影响,分别从爆破和静力施工阶段两个方面进行综合分析。结果表明:新建隧道的开挖进尺控制在1.5 m,最大允许装药量控制在7.54 kg,爆破震速可控制在3 cm/s以内,特大断面隧道群施工对新建隧道的爆破震速在安全可控范围内;既有隧道的最大变形为2.9 mm,围岩主应力的前后变化值为1.50%以内,衬砌应力的最大应力变化值为4.17%,特大断面隧道群施工对新建隧道的影响不大。最后,根据分析结果提出施工期的保障措施。
In this paper,three-dimensional finite element is used to study the influence of new tunnel group construction on the existing tunnel based on the new tunnel group underneath passing the existing Dongfengshan tunnel engineering in the southeast section of Fuzhou ring road.The analysis method is carried out from two aspects of blasting and static construction stage.The results show that in order to make the blasting vibration speed of the new tunnel under the control of large cross-section tunnel group construction within the safe and controllable range,the excavation footage of the new tunnel shall be controlled within 1.5 m,the maximum allowable charge shall be controlled within 7.54 kg,and the blasting vibration speed shall be controlled within 3 cm/s.The maximum deformation of the existing tunnel is 2.9 mm,the change value of the main stress of the surrounding rock is within 1.50%,the change value of the maximum stress of the lining is 4.17%,and the construction of the large cross-section tunnel group has little influence on the new tunnel.Finally,according to the analysis results,the guarantee measures during the construction period are put forward.
作者
洪永佳
HONG Yongjia(Fuzhou Planning Design&Research Institute,Fuzhou 350100,China)
出处
《路基工程》
2020年第6期54-59,共6页
Subgrade Engineering
关键词
隧道群
下穿高速公路隧道
数值分析
爆破震速
变形
应力
tunnel group
underpass the highway tunnel
numerical analysis
blasting vibration
deformation
stress
