Application Of Slope Surface Point Rotation Azimuth Monitor In Landslide Monitoring

Oblique(side)slope deformation monitoring is an important means to prevent landslides and other geological disasters,and it is also one of the e ffective ways to guide the comprehensive prevention and control of geological disasters.Based on the development of the slope point rotation azimuth monitor,relying on the school's large-scale landslide-debris flow physical simulation device a rainfall-rype inclined contact surface loess landslide model was constructed,and the dynmic change characteristics and change trend of the slope surface point rotation azimuth during the development process of the landslide deformation were tested.,And based on rock and soil testing technology,further reveal the deformation failure mode and deformation failure mechanism of rainfall-type loess landslides.The main research results include:(1)Based on rock and soil deformation monitoring technology,micro-electromechanical technology,and wireless communication technology,we independently developed a slope surface point rotation azimuth monitor which covers five major designs of hardware software,external structure,data communication and anti-interference.It can realize the digitization and automation of the slope point rotation orientation monitoring when the slope surface displacement changes.(2)According to the law of slope point rotation azimuth monitoring data,find out the change characteristics of landslide development and evolution process.Rainfall for slide of landslide with rainfall test,the test results show that the type of rainfall stages of loess landslide evolution process can be generalized into a stable inoculation,uniform deformation stage and accelerated destruction stage,among them,the stable inoculation phase accounted for 99.5%,when the whole landslide uniform deformation stage of 0.2?0.3%,and accelerate the failure stage was only 10?30 s,The burst characteristics of rainfall-type loess landslides are furher verified.(3)The results of rock and soil test show that:the seepage path of soil water in rain-induced loess landslide is complex,but the water content presents a five-stage trend of "gentle-rapid increase-slow increase-peak-stable".When the soil moisture content tends to be stable,the soil pressure reaches the peak,the shear strength of the soil is destroyed,and tensile cracks appear on the surface of the slope.With the continuous development of fractures,the earth pressure gradually decreases,and the slope deformation and failure occur in the slip-tensile fracture type.(4)The tilt of the loess landslide under the effect of rainfall,the sliding zone soil lead in water saturated by the trailing edge inclined fracture water infiltration,the soil shear strength decreases and increases soil vertical infiltration of surface water makes the severe,tilted contact surface loess landslide slip force increases gradually,when a balanced slope destroy limit,landslide disaster occurred.