| As the country of the west development, more and more airport built in themountains and mountainous terrain fluctuation change is big, high fill slope stabilityis facing a major among airport construction process safety issues. The high fill slopestability under rainfall conditions more prominent; So the high fill slope stability inlong under the condition of rainfall is of great significance. Research on high fill slopestability are commonly used numerical simulation and physical simulation.Indoorcentrifugal model experiment developed rapidly in recent years, and more and moreused in the field of engineering, involving DAMS， underground structures,geotechnical foundation, retaining wall, tunnel and all kinds of slope stability. Indoorcentrifugal experiment can use a smaller model structure under high accelerationenvironment, simulate the hundreds large relative to the model of entity, fullyimplement the stress field of the remodeling process, the physical mechanism of someof the more complex and lasted longer in a relatively short period of time bycentrifugal acceleration. In this paper, with the aid of chengdu university oftechnology state key laboratory of geotechnical centrifuge TLJ-500of panzhihuaairport issue of landslide is simulated. In addition to all this through the Geostudio-2007software seep of numerical simulation of landslide and slope module. Throughthe numerical and physical simulation, Main study achievements are described asfollows:（1）Geostudio-seep simulated rainfall infiltration, rainfall, slope surfaceinstantaneous saturated, rain slow vertical slope facing the internal infiltration; Withrainfall number increase, the slope overall moisture content increases gradually,outgoing slope in water content decreases, reduced gradient with the increase ofrainfall frequency is more and more small.（2）Geostudio-slope module, according to the calculation results of the firstand secondary precipitation are divided into60ml,120ml, rainfall interval for5days,little impact on the stability of the slope, because time is short, small and rainfallinfiltration infiltration depth is not enough; Second rainfall six days after the third andfourth times, rainfall, rainfall is240ml, and had a greater influence on the simulation results show that the rainfall on the slope, the slope stability coefficient from1.09to1.01, in the stability of the zero bound state, mainly due to:(1) increased rainfall,infiltration volume increased water content increasing;(2) increase rainfall infiltrationtime infiltration depth deepening;(3) is influenced by two previous rainfall infiltrationwater content and the infiltration depth increases. Rainfall for the fourth time12daysafter the fifth rainfall, rainfall is300ml, affected by the four previous rainfall and therainfall increase, the biggest effect on slope stability, the stability coefficient from1.01to0.85, the landslide.（3）Centrifugal model accelerate from0g to120g, equivalent to a prototypefilling height from0.29m to35m, filling the small settlement deformation of slopebody; Under120g run at a constant speed, equivalent to a prototype filling height of35m, is the slope of uniform process natural sedimentation process, according tocentrifuge model moisture content sensor monitoring data show that in the first fourtimes artificial rainfall infiltration depth is not enough, did not significantlydestructive effects on the slope, increased the slope settlement and creep down slopedegree, slope edge place soil creep-subsidence and more apparent, according tomonitoring data show that maximum subsidence in nearly2cm,2.4m is equal to thesettlement of prototype; Slope toe frontal uplift relatively obvious (and panzhihuaairport frontal uplift deformation in the process of long-term rainfall is consistent),rainfall on slope at the same time must be washed.（4）Accelerate in120g to150g and accompanied by rain, the equivalent of aprototype filling height from35m filling to45m and with rainfall, higher because ofthe filling body, earth pressure increase, with the increase of rainfall, duration,frequency of slope with higher water content, soil softening and shear strength isreduced, the147g (43.5m) prototype height is apparent damage, deformation ofslope body, the top front obvious crack, sink and sliding distance stop (and panzhihuaairport landslides occur, trailing edge cracking slope forward slip fit); Big toe frontaluplift deformation, uplift the highest thickness of5.9cm, equivalent to a prototypehigher height of8.85m. The above shows that the slope of slope body goes badmechanisms for creep model, the upper is given priority to with time cracking, thelower is given priority to with creep deformation.（5）Slope surface from trailing edge began settling29cm, to97cm, middlesettlement is the largest,6.5cm, equivalent model of settlement of prototype of9.75m, the subsidence trend on both sides to irregular wavy decreased; Three fracture belt,broken top development respectively from the trailing edge distance of40cm,60.9 cm,80.9cm; Discontinuous crack fracture zone corresponding to the glass side justdevelopment. According to monitoring data of sensors and the experimentalphenomenon reason#5and1) fracture zone between a run-through pull crack,downwards to the silty clay layer formation damage. This is similar to panzhihuacharacteristics of landslide and slope trailing edge cracking down development to siltyclay layer in silty clay layer formed after the sliding zone, slope sliding down thesliding zone as a whole.（6）Panzhihua airport issue of landslide is an induced by rainfall for reason, tointernal long-term infiltration of its trailing bedrock fissure water in geotechnicalengineering conditions and rainfall infiltration in the process of filling of the fillingbody under the influence of water content increase, groundwater long-term abusebubble, to soften the root cause for occurrence of landslide, rock and soil mass failuremode is goes on-creep type, slope is given priority to with sliding-ripping, slope toeto give priority to with creep-uplift deformation. |
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