Research On The Mechanics About Accident Of Subway Engineering With Refrigeration Construction Technology And Its Repairing Thechnology

The connecting passage’s construction between the two tunnels of undergroundamong the intermediate air shaft’s lower part are in great danger, leading to the loss ofa large number of soil around the tunnel, long about270meters’ tunnel got collapseddamage, and large ground subsidence, the largest settlement amounted to7meters, thearea of the accident ground’s buildings of different degree of tilt and destruction.In this paper,taking an intermediate air shaft of the Shanghai Metro freezeaccident as the basis, Through study on the incentive, the cause of, the occurrence ofthe disaster process, formation mechanism, lessons from the accident, accident rescueand prevention, risk management control study and so on,which to freeze constructionaccident in the subway construction process, has important reference value for China’sfuture subway construction in risk aversion and prevention. At the time of the study,through a comprehensive collection and analysis of the Shanghai Metrointermediate air shaft’s engineering geological conditions, hydrogeological conditions,the mechanical properties of frozen soil, soil distribution, engineering investigations,engineering design, site construction, supervision and monitoring, Mainly including the data of physical and mechanical properties of the formation of accident analysis,frozen soil mechanics characteristic analysis, the freeze design scheme that comparedwith the new design scheme. Then, on the basis of engineering geological conditionsand mechanical properties’ data, the establishment of the corresponding numericalmodel, mathematical model, analysis of the stability of tunnel under the originaldesign, the new adjustment programs under the freeze Instability mechanism, nalysisof seepage characteristics and seepage theory after water inrush, mechanics analysisof tunnel support structure’s instability, the tunnel surrounding soil’s deformationmovement rules, and the surface response analysis of adjacent building foundation,etc., by numerical calculation to reproduce the failure process and reveal themechanism of instability. At the same time, using numerical calculation to study onflow-solid coupling theory in the connecting passage excavation’s process under thefreeze curtain. Explore the contact channel’s water inrush formation mechanism, andstudy the corresponding numerical methods, making computer simulation analysisof the tunnel’s water inrush procedure under different temperature conditions and theweak and freezen parts. A comprehensive and in-depth study in order to freeze theShanghai Metro Line4middle range air shaft mechanism of the accident, so conducta comprehensive and in-depth study on the Shanghai metro line4middle range airshaft’s freezing accident mechanism, and put forward some countermeasures for therepair and technical analysis, put forward the cause of the accident and learn lessons,and provide a valuable reference for the same type of freeze construction in the future.