|
Abstract In order to study the deformation law of entrance section for loess highway tunnel，based on the right line of Liujiaping No.2 tunnel of highway from Wubu to Zizhou in Shaanxi Province，in-situ tests were conducted. The tunnel construction deformation was measured，and the regression analysis was made in data processing of in-situ test. The results show that：(1) From the arch subsidence and clearance convergence data of the same time in two sections，it is found that the arch subsidence is greater than clearance convergence，so the arch subsidence should be mainly controlled during the construction：(2) The deformation data reflect the bias voltage of the portal section. (3) Tense curve of the arch subsidence is basically stable，the main indicator is the tense curve of subsidence gently rising，but the deformation rate decreases gradually which shows that the loess strata become stable；(4) The tense curves of 6 arch subsidence in two section are basically the same，it shows that although the sidewalls and inverted arch experience a tremendous spatial variation during the construction，there is no obvious mutation in the tense curve of the subsidence. The displacement law of the Malan new set loess stratigraphy was shown，and the time effect was more significant than spatial effect. The study results can provide a theoretical basis for the design and construction of the portal section，and a reference for similar tunnel project portal section construction.
|
|
Received: 29 May 2012
|
|
|
|
2013, Vol. 32 
