考虑局部缺陷的大断面隧道非线性承载性能研究
Research on nonlinear bearing performance of large section tunnels considering local imperfections
周奇辉 1张琼方 1王震 2丁智 2孙苗苗 2吴梦琴3
作者信息
- 1. 中国电建集团华东勘测设计研究院有限公司,浙江杭州 310014
- 2. 浙大城市学院 工程学院,浙江 杭州 310015;浙江省城市盾构隧道安全建造与智能养护重点实验室,浙江杭州 310015
- 3. 浙大城市学院 工程学院,浙江 杭州 310015
- 折叠
摘要
大断面衬砌管片广泛应用于水利水电工程中的泄洪隧洞、输水隧洞等领域,而管片施工误差与运营堆卸载等不利因素引起的局部缺陷将影响到其承载性能.为此,考虑管片几何缺陷影响,提出了大断面隧道衬砌的非线性承载力求解方法.针对管片弧度不平整、径向错台这两类典型缺陷形式,考虑不同缺陷幅值、局部缺陷模式和缺陷分布等初始条件参数,给出了大断面隧道衬砌极限承载力的设计取值.研究表明:局部几何缺陷对管片承载力有不利影响,荷载系数受不同缺陷幅值的影响,变化趋势为先线性增大,随后非线性平缓增大并收敛;局部几何缺陷下,单片、多片缺陷分布工况受到的影响较小,而半跨、全跨工况受到的影响相对较大,实际工程中综合考虑各单因素缺陷的叠加影响,管片极限荷载系数取折减系数0.80～0.85 较为适宜.
Abstract
Large section lining segments are widely used in drainage tunnels,underwater tunnels and other fields in water re-sources and hydropower engineering.The manufacturing errors and local imperfections caused by piling and operation will influ-ence the bearing capacity of the segment lining structures.For this reason,a calculation method for the nonlinear bearing perform-ance of large section segments considering initial imperfections was proposed.Aiming at two typical imperfections,out-of-flat-ness imperfection mode and radial dislocation imperfection mode,through considering different imperfection amplitudes,local im-perfection mode and imperfection distribution,we analyzed the ultimate bearing capacity values of large section lining segments.The results show that the local geometric imperfections mainly have adverse effects on the bearing capacity of segments,and the corresponding loading coefficient is affected by different imperfection amplitudes,with a variation trend of linearly increasing first,nonlinear gently increasing and coming to a convergence.For the local geometric imperfections,the influence is small for single and multi-slice imperfection cases,while the influence is relatively large for half-span and full-span cases.In practical engi-neering,comprehensively considering the superimposed adverse influence of each single-factor imperfection forms,the reduction coefficient of segment ultimate loading coefficient is suggested as 0.80～0.85.
关键词
隧道衬砌/局部缺陷/非线性稳定/缺陷分布/折减系数Key words
tunnel lining/local imperfections/nonlinear stability/imperfection distribution/reduction coefficient引用本文复制引用
基金项目
国家自然科学基金项目(52178400)
浙江省重点研发计划项目(2020C01102)
杭州市农业与社会发展科研项目(202203B39)
出版年
2024
国家科技期刊平台
NSTL
万方数据