中日盾构隧道-工作井接头抗震设计及研究进展综述

Review of Seismic Design and Research Progress of Chinese and Japanese Shield Tunnel-Working Shaft Joints

首先通过比较中日两国规范及标准中的盾构隧道-工作井接头要求,阐述中日抗震设计理论现状。分析认为:中国的设计规范对井接头的抗震规定较为模糊甚至较少提及,日本规范存在2种盾构隧道-工作井柔性接头的抗震计算方法。相比之下,日本拥有更成熟并且实用的抗震分析理论和计算方法。中日在设计规范标准中均给与设计单位巨大的自由度,但结果允许值的取值范围缺乏评价标准。其次,通过调研井接头抗震分析的研究进展,指出井接头部位的震害特点和关键影响因素;并从影响井接头综合响应机制的关键要素,如刚度比、结构间的相互作用、地基承载力、刚性接头和柔性接头的对比等,对井接头研究现状和不足进行综述。再次,对井接头的抗震评价方法和抗震措施进行梳理,认为:1)土和结构刚度比对工作井接头产生显著影响,需要注意控制工作井周围的土层刚度在合理范围内,提出结构和结构的刚度比是未来重要研究方向的建议。2)结构之间的相互影响主要关注在不同的地震荷载下,2个结构相互之间的影响机制。提出对于结构的相互影响还应关注盾构隧道和工作井接触研究的思考。3)除了结构刚度突变外,地基刚度突变也是重要的影响因素。日本已经提出简易评价公式并经过验证,中国目前在这方面的研究较少。提出软土地区应该着重进行此类研究的建议。4)在柔性抗震方面,日本进行了深入研究。考虑到中国即将要求盾构隧道-工作井接头采用刚柔结构的新规范,日本的研究成果可以为中国进一步发展盾构隧道-工作井接头的抗震设计提供参考。最后,预测本研究领域可能的未来发展方向。

By comparing the requirements for shield tunnel-working shaft joints in Chinese and Japanese codes and standards,the current state of seismic design theories is presented.It is found that Chinese design codes for shaft joints exhibit vagueness and,in some cases,minimal references to seismic resistance;in contrast,Japanese standards encompass two seismic calculation methods for flexible joints in shield tunnel-shaft structures,showcasing more mature and practical seismic analysis theories and computational approaches.Both China and Japan afford significant freedom to design units in their respective design standards,yet the permissible value ranges lack evaluation criteria.Furthermore,the research progress in seismic analysis of shaft joints is investigated,identifying seismic characteristics and key influencing factors at shaft joint locations. Based on this, the current status and deficiencies in shaft joint studies are proposed, focusing on key elements influencing the comprehensive response mechanism of shaft joints, including the impact of stiffness ratio, interaction among structures, effects of ground bearing capacity, and a comparative study of rigid and flexible joints. Finally, after summarizing and evaluating seismic assessment methods and measures for shaft joints, conclusions are drawn as follows: (1) The soil-structure stiffness ratio significantly affects working shaft joints, emphasizing the need to control the stiffness of the soil layer around working shafts within a reasonable range. Moreover, investigating the stiffness ratio between structures is recommended as a key area for future research. (2) The interaction between structures primarily focuses on the influence mechanism between two structures under different seismic loads. Thus, considerations for structural interaction should also be extended to the study of shield tunnel-shaft junction contact. (3) In addition to sudden changes in structural stiffness, stiffness discontinuity in foundation stiffness are also important influencing factors. While Japan has proposed a simplified evaluation formula and validated it, research in this aspect is relatively limited in China. Such research should be emphasized in soft soil areas. (4) Japan has conducted in-depth research on flexible seismic resistance. Considering that China will soon require a new standard for rigid-flexible structures for shield tunnel-working shaft joints, Japanese research results also provide a useful reference for China to further develop seismic design of shield tunnel-working shaft joints. In addition, the possible future development direction of this research field is predicted.