摘要
盾构隧道的施工会引起周边地层的沉降和位移,从而对周边建构筑物产生影响,因此在项目实施前通常要对隧道开挖的影响进行评估。依托浙江宁波某在建管廊盾构工程项目,利用MIDAS GTS商业有限元分析软件模拟盾构隧道临近既有电力工作井施工过程,通过改变周边地层(等代层)刚度反映盾构施工扰动。数值分析研究表明,地层损失率对电力井的内力变形影响非常显著,随着地层损失率的增加,电力井最大沉降量、电力井壁最大应力、底板最大应力呈显著增加趋势。结合当地相关文献资料,推算盾构施工使电力工作井产生的最大沉降值为4mm,最大差异沉降为0.00032,最大应力增量为453kPa。预测结果表明,盾构隧道的掘进对电力工作井的影响处于可接受范围内,在施工过程中应制定合理的监控量测方案,需要密切关注电力工作井与盾构隧道的安全状态。
Shield tunneling always cause serious settlement and displacement of surrounding strata,which is threatening the safety of adjacent buildings.Therefore,it is necessary to evaluate the impact of tunneling before construction.Based on a tunnel project under construction in Ningbo,Zhejiang,numerical simulation is conducted using MIDAS GTS commercial finite element analysis software.The disturbance during shield tunnel construction is reflected by changing the stiffness of the surrounding strata.Numerical analysis shows that the loss ratio of stratum has a significant impact on the internal force and deformation of the power well.With the increase of formation loss rate,the maximum settlement of electric well,the maximum stress of electric well wall and the maximum stress of floor increase significantly.Based on the monitoring data from local literature,it can be estimated that the maximum settlement value,the maximum differential settlement and the maximum stress increment of the electric working well produced by the shield construction are 4mm,0.00032 and 453kPa respectively.The results indicate that the impact of shield tunneling on the power working shaft is within an acceptable range.Reasonable monitoring and measurement plans should be developed during the construction process and more attention should be paid on the safety status of the power working shaft.
出处
《福建建设科技》
2023年第5期26-29,共4页
Fujian Construction Science & Technology
关键词
盾构施工
有限元分析
安全评价
地层损失
沉降分析
shield tunneling
finite element analysis
safety assessment
numerical simulation
作者简介
陈苏(1981.04-),男,硕士,高级工程师,研究方向:盾构隧道施工、有限元分析、安全评价、数值分析等。E-mail:7684038@qq.com。
