Research On Artificial Induced Landslide By High Pressure Water Injection

In recent years,the global geological structure movement is active,strong earthquakes and large-scale landslide events are frequent,and the scope of human construction activities is expanding,people often face the great threat of all kinds of landslide geological disasters.Therefore,it is of great significance to put forward reasonable and effective prevention and control measures.In this paper,a method of landslide induction by high-pressure water injection is proposed,that is,according to the engineering needs,a sliding surface is artificially preset on the hidden slope,and high-pressure water is injected on the preset sliding surface to induce and control the preset slope to slide to the safe position,so as to achieve the radical treatment of hidden landslide.It has a good practical application prospect in mountain road construction and barrier lake prevention and control.In order to verify the feasibility of artificially induced landslide by high-pressure water injection,the research method combining model test and numerical simulation was adopted to explore its rule and mechanism.The main conclusions are as follows:(1)Both model test and numerical simulation show that high-pressure water injection can induce potential landslide failure according to the preset slip surface,which confirms the feasibility of high-pressure water injection induced landslide.(2)There is starting pore pressure in landslide induced by high-pressure water injection:When the water injection water pressure reaches the starting water pressure,the time required for landslide instability is rapidly shortened,because the pore water pressure of the soil near the water injection point rises rapidly,resulting in a sharp decline in effective stress,and a continuous sliding surface is formed between the water injection points,resulting in slope instability.(3)When the water injection pressure is low,the time required for landslide instability is longer,which is similar to the mechanism of landslide instability caused by rainfall infiltration.In other words,under the long-term infiltration of water,the soil weight increases,the pore stress increases,and the shear strength decreases together,which leads to the instability of the slope.(4)When the water injection pressure is much larger than the critical water pressure,the time required for water-injection induced landslide instability is not significantly shortened,because the high water pressure leads to breakdown below the water injection point,and the high pressure water quickly flows out.Continuous high pore pressure cannot be formed in the slope body,and it is difficult to form a continuous slip surface.(5)The pore pressure distribution pattern near the injection point is as follows: below the injection point > water level > above the injection point.For example,under the pressure of 10 k Pa,the pore pressure 10 cm below the injection point is 40%-44% of the injection pressure,and the pore pressure 10 cm away from the same water level of the injection point is 36%-39% of the injection pressure.(6)The pore pressure decreases with the increase of the distance from the injection point.For example,under the pressure of 10 k Pa,the pore pressure 10 cm away from the same level of the injection point is 36%-39% of the injection pressure,and the pore pressure 20 cm away is 21%-23% of the injection pressure.