رفتارهای لرزه ای یک تونل ابزار
Abstract
۱٫ Introduction
۲٫ Testing design and instruments
۳٫ Analysis of testing results
۴٫ Summary and conclusions
Declaration of competing interest
Acknowledgments
Appendix A. Supplementary data
Research Data
References
Abstract
Shaking table model tests were carried out to study the seismic behaviors of double box utility tunnel with joint connections and the surrounding soil. The seismic wave obtained from 1952 Taft earthquake was employed as the input in this study, and its PGA has been adjusted to 0.2 g, 0.4 g, 0.8 g, and 1.2 g, respectively. In addition, a series of sine waves with PGA of 0.2 g and frequencies of 5 Hz, 10 Hz, 15 Hz, 20 Hz, 25 Hz, and 30 Hz were applied to study the effect of frequency characteristics on seismic behavior of the utility tunnel and the surrounding soil. The testing results show that the laminar soil container does not impose significant boundary effect, and the dynamic earth pressure response is significantly influenced due to existence of the joint connection. Besides, the effect of soil-structure interaction on seismic behaviors is becoming even more obvious as the input PGA increases. The acceleration response is also significantly influenced by the dynamic property of the soil. Greater bending moment occurs at the corners of the structure, and its increasing ratio will decrease with an increasing input PGA magnitude. Lastly, the effect of frequency is significant. Therefore, it is noteworthy that the possible effect of natural frequency is considered when the utility tunnel is under construction.
Introduction
The role of underground lifelines (like water pipe, gas pipe, and electric wire) is drawing increasing attention in modern developed societies where living conditions, the economic, cultural and social activities are increasingly dependent on a complex network of lifelines [1]. How to maintain the operation of these lifelines, as well as the ensurance of safety, becomes a key issue. Nowadays, underground utility tunnel, an emerging infrastructure, is gradually applied for development of city due to it is multifunctional and maintenance-friendly [2]. Despite that the seismic performance of underground structure has been paid attention since the 1995 Kobe-Osaka earthquake [3,4], the study on seismic behavior of underground utility tunnel is not systematic and enough. The research results of seismic behavior about other underground structures are not suitable for application of the underground utility tunnel, because it has some extinct features, like relatively small cross section, shallowly buried, and relatively simple structure pattern. Since many pipelines for water, electricity, and natural gas, etc. will be put into it, the consequences are unimaginable once earthquake occurs. Therefore, it is essential to conduct the research on seismic behavior of underground utility tunnel and the surrounding soil. From the aspect of seismic behavior research of underground structure, many researchers have made great efforts and achieved a lot of achievements.