Applied Mechanics and Materials Vols. 580-583

Abstract: With more and more subway lines in cities, people have pay much attention to the comfortable quality of subway vibration, especially in transfer stations or stations that have more than one line which platform and floor have much violent vibration. The paper bases on a subway station with multiple trains, builds the finite model, puts measured wheel-rail force as the load and gets the dynamic responses. Then it accords conventional international standard of comfortable quality which uses weighted root mean square acceleration as index to evaluate the comfortable quality of platform and floor or other areas. The result shows: The station could meet the requirement of comfortable quality.

Abstract: The mechanical properties of tunnel surrounding rock in fault zone is usually quite weak, and the support pressure and displacement are larger than other sections, so the support type in fault zone is a critical issue for tunnel safety. Three types of tunnel support through fault zone were analyzed by finite element method (FEM): ①Reinforced concrete support, ②bolting-shotcreting and reinforced concrete support,③grouting and reinforced concrete support. The result shows that support stress and surrounding rock displacement with grouting and reinforced concrete support is quite smaller than the other support types.

Abstract: arch tunnel construction in the presence of construction mechanics often unclear, the lack of systematic design and construction of the theory can learn. Harbin Clinic Road thesis double-arch tunnel project as the basis, the construction process through its hole + CRD using the finite element simulation analysis and on-site monitoring measurement data processing, engineering arch tunnel song used in the wall study the mechanical properties.

Abstract: The reason situ stress is very complicated, and it is still not very clear question. In this paper, the construction process through practical engineering analysis on a variety of construction methods and steps arch tunnel to study the effects of different excavation methods and deep anchor support large section tunnel under guard by theoretical analysis of surrounding rock stress field, strain field and variation of the displacement field, analysis of different rock excavation methods, supporting stress state characteristics, in order to optimize the choice of tunneling method provides a theoretical basis. Under the conditions all kinds of rock reasonable steps to secure construction methods put forward and lay the foundation for long-term safety arch tunnel.

Abstract: It is a hard engineering problem for the shield machine passing through the capital airport apron in shallow soft soil. Tunneling parameters were obtained from the 50m simulation test section ahead the apron. The shield machine kept tunneling steady and balanced by optimizing the control technology of soil pressure and grouting. According to the monitoring results, the secondary and repeated grouting technology was applied timely. The deep splitting grouting technology was used when the monitoring value exceeding control standards. The settlement value was effectively controlled.

Abstract: To choose an appropriate construction scheme for subway, it,s feasible to use fuzzy optimization theory and comprehensively consider the security of four construction methods as well as such factors as environmental influence, construction period, construction difficulty and construction cost, etc. to set up a mathematical model for the construction method of subway station. An analysis is made on the impact of group-effect in the excavation construction of pilot tunnel presented in PBA construction method on arch crown settlement and ground surface settlement, and a study is made on the arch crown settlement and ground surface settlement caused by the four construction methods in construction process. In addition, a contrastive analysis is made to draw a conclusion that PBA construction method is the most suitable construction method for Xinbai Square Subway Station in Shijiazhuang.

Abstract: Quality defects and diseases will happen to railway tunnel after it in operation four to five years later, such as lining split, water leakage and landslide of second lining. Based on the case of Goujiagou tunnel located at Ⅳ surrounding rock with mudstone and sandstone, the regulation for this tunnel is put forward; the causes and characteristics of all kinds of defects are analyzed by studying on the particularity of railway tunnel construction. Based on different extend of injury, the classification of the same type defect is proposed. Research results indicate that the regulation design is feasible and the treating technique is appropriate by using new technology, methods and materials. The results will provide reference to design for the same type tunnel regulation.

Abstract: Zhengyangmen gate tower is a national emphasis cultural relic unit along the north-south axis of Beijing, which is above the Beijing metro line 2. Based on dynamic analysis model of gate tower and the position of gate tower and subway, the dynamic response characteristics of gate tower induced by Beijing metro line 2 are calculated, and compared with the in-site vibration test data.

Abstract: Due to the impact of geological condition, climate condition, design, construction and other factors, the existing railway tunnel appears some diseases more and more, and even some diseases have serious influence to the normal use of tunnels and traffic safety. To eliminate these dangers, we should understand the type of diseases and their causes. Based on the existing tunnel disease investigation and analysis, tunnel diseases were classified, the reason of tunnel diseases were analyzed, which can provide a reliable basis for the tunnel disease treatment. The result indicates that railway tunnel diseases include lining water leakage, lining structure disease, lining concrete disease, foundation disease, lining off block and so on. All kinds of diseases of tunnel lining are often interrelated, so the tunnel disease usually is a result of multiple factors.

Abstract: As the primary technique to offer safety and productivity improvement s for under- ground project s , rock bolt s have been widely used in t he construction of t raffic and hydro- power stations. The quality of the rock bolt s is of great importance and has been paid a lot of at tention to. This paper reviewed the history of some techniques used for the inspection of rock bolt s and analyzed their t heory and application. It point sout that the t heoretic p roblem is t he primary problem existed in t hese techniques.Nondestructive testing of bolt develops quickly with plenteous accomplishments and experiences.And we state these accomplishments mainly and look into the future.