The Safety And Corrosion Study On The Concrete Lining Of Xia'men East Passage Subsea Tunnel

Using concrete strain gauges for the concrete lining safety monitoring is commonly used in tunnel monitoring.In order to grasp the status change, judging the safety of the tunnel structure during the Xia'men east passage subsea tunnel construction, lining stress monitoring sections are set in the bad geological areas. This paper based on the analysis of the gauging data evaluate the lining safety, using numerical simulation analysis steel corrosion on the impact of structure,and draw some useful conclusions.This paper mainly consists of three parts: field test about the free volume strain of concrete; current load distribution and safety of concrete lining; analysis for rebar corrosion on the impact of lining.In order to get the true stress of the lining, the concrete non-stress meter was used in gauging free volume strain of concrete for the first time.In the calculation of lining stress,deduct this free volume strain to obtain the actual lining stress .Taking into account concrete creep, effective modulus is adopted in the calculation.Through statistical analysis of the stress of gauging section, get the force law and safety of lining in the current shallow areas.The paper also adopts field test method and finite element analysis method to analyze the load distribution pattern and the load ratio of concrete lining.Taking into account the working environment of the subsea tunnel,the paper analysis rebar corrosion expansive force on the impact of concrete tension stress and cracks of different concrete cover;discussed the bond degradation between the steel and concrete on the impact of crown settlement, lining stress,steel stress,bond-slip and cracks;calculate the cracking load of lining in water situation and anhydrous situation,get the controlling factors that lead to lining stress increased.