| With the acceleration of urbanization procedure in our country,the cross-river tun-nel can well solve the problems across the waters;at the same time because of the e-nvironment to the ground little influence;strong ability to adapt to climate conditions,do not restrict the development of shipping,seismic performance,strategic significanc-e higher superiority,has been widely used in recent years through the river project.The cross-river tunnel project may cause the deformation or even seepage damage of the embankment,which will endanger the safety of the embankment.The system research in this area is not much.In this article the numerical method is used to simulate the seepage stability and deformation of the embankment engineering through multiple operating conditions.The main research contents and achievements are as follows:(1)According to conducting impact analysis on the tunnel’s cover thickness,distance from the entrance of ramp to the embankment,ground water and any other factors,which to obtain the seepage stability and deformation of the embankment engineering.It turns out that within the scope of the levee engineering,with closer distance from cross-river tunnel ramp entrances and exits to dike and lower underground water level.The hydraulic grade will be greater,which has worse effect on the seepage stability of the dike.But the higher underground water level,the greater the settlement of levee crest and ground surface are,which has worse effect on settlement stabilization.The tunnel’s cover thickness almost has no effect on the embankment’s hydraulic gradient,but it does affect the embankment’s settlement deformation,so the cover thickness must be defined according to specifications or experience.(2)According to conducting impact analysis on the tunnel’s cover thickness,relative distance from the major entrance to the embankment,ground water and any other factors,which to obtain the seepage stability and deformation of the embankment engineering.It turns out that within the scope of the levee engineering,with closer the distance from major entrance and exist to the embankment and lower ground water level,the hydraulic gradient will be greater,but the change of relative distance and groundwater level has little effect on settlement.with further distance from cross-river tunnel major entrances and exits to dike,the settlement is greater.The precondition for settlement calculation of model is less than the maximum allowable hydraulic gradient,namely the model does not occur infiltration and sabotage.Therefore,in order to select the appropriate tunnel’s cover thickness,distance from the entrance of ramp to the embankment,relative distance from the major entrance to the embankment should first consider the seepage stability of the embankment,then consider deformation of the embankment engineering.(3)The research about the part of a tunnel,that the section of the cross-river,to explore the effect of cross-river tunnel engineering on the seepage stability and the settlement deformation of the embankment under different water level combination condition.It turns out that: Within the enactment range of research,In the same water level combination that the water level of riverbed side is higher than the water level of urban side,When the water level of riverbed side is unchanging,the water level of urban side is lower(in a word that the underground water level is lower),the maximum hydraulic gradient of the embankment and the largest settlement have a tendency to increase.When the water level of urban side is unchanging,the water level of riverbed side is lower,the maximum hydraulic gradient of the embankment and the largest settlement become smaller.In the construction of cross-river tunnel that the tunnel’s construction period should be chosen in a suitable time period,such as The river during dry season periods or the difference between the water level of riverbed side and the unban side as small as possible. |
