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| Research on the Mechanical Behavior of the Tunnel Crossing Tertiary Silty Clay |
| ZHAN Hong – yue |
| (TheThird Railway Survey and Design Institute Group Corporation，Tianjin 300142，China) |
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Abstract Abstract : Research purposes ： Mechanical properties of Tertiary silty clay change greatly in different moisture conditions. The main purpose of the study is how to effectively combine the numerical simulation monitor witli site monitoring measuring to determine the reasonable supporting time and appreciate measures to ensure the tunnel passing through the terrestrial layer smoothly. Research conclusions：( 1 ) Through the analysis of numerical simulation， during the tunnel construction， stress of surrounding rock will redistribute，strengthen of soil will greatly reduced because of leakage，deformation will increase. Primary support can efectively control the deformation of surrounding rock， therefore reasonable process should be planned to ensure the primary support in time. (2) After testing and analysis， we know that with the increase of moisture content of surrounding rock， rock elastic modulus， cohesion and internal friction angle will become smaller， and the deformation of the support structure will increase. Therefore， in order to guarantee the safety during construction，reasonable support measures according to different moisture content should be used and the working faces should be closed timely. (3) During the construction，dynamic design should be done based on the supervision data to determine the reasonable time of the lining. Generally，it is better to do the secondary lining after 20 days，because the surrounding rock stress and deformation tend to be stable after 20 days. (4) The research results will be a reference for the design and construction of tunnel pasing through the similar formation.
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Received: 26 December 2016
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2017, Vol. 34 
