The siphon drainage is an effective measure for the slope groundwater control. However,for the traditional siphon drainage, limitations such as siphon lift restriction and poor reliability in longterm service prevent ...The siphon drainage is an effective measure for the slope groundwater control. However,for the traditional siphon drainage, limitations such as siphon lift restriction and poor reliability in longterm service prevent it from being widely used. In this study, an improved siphon drainage method with inclined borehole penetrating the deep part of the slope is proposed to overcome the limitations suffered by the traditional method. Through experimental research, theoretical analysis and engineering practice,the reliability and capability of the proposed method are investigated. The results demonstrate that with the inclined pipe the height difference between the control point of the groundwater level and the orifice can be controlled to be less than the height of the water column corresponding to the local atmospheric pressure. As a result, deep drainage can be achieved.In addition, by controlling the diameter of siphon drainage pipe not larger than 4 mm, a plug flow can be formed in the siphon pipe, which can prevent air accumulation in the siphon process and a continuous and effective siphon drainage is achieved. Through a practical project running smoothly since September 2013, it is found that the proposed method can effectively drain the groundwater deep in the slope and the maximum drawdown of groundwater level in boreholes can reach 8.5 m with an average drainage flow of 5.5 m3/d. The practical results also illustrate that 4 mm siphon pipe can be used to realize deep slope drainage and restart siphon automatically.展开更多
An optimal drainage tunnel location determination method for landslide prevention was proposed to solve the existing problems in drainage tunnel construction. Current applications of drainage tunnel systems in China w...An optimal drainage tunnel location determination method for landslide prevention was proposed to solve the existing problems in drainage tunnel construction. Current applications of drainage tunnel systems in China were reviewed and the fimctions of drainage tunnel were categorized as catchment and interception. Numerical simulations were conducted. The results show that both catchment and interception tunnels have variation of the function in the simulation of monolayer model, which shows the reduction of permeability condition in lower layer. The function of catchment can be observed in the deep slope, while the function of interception is observed near groundwater source. By using the slope safety factor and discharge water amount as the objectives of optimal drainage tunnel location, and pore-water pressure in fixed node and section flux as the judgment for construction quality of adjacent drainage tunnel, the design principle of drainage tunnel was introduced. The K103 Landslide was illustrated as an example to determine the optimal drainage tunnel location. The measured drainage tunnel efficiency was evaluated and compared with that from the numerical analyses based on groundwater data. The results validate the present numerical study.展开更多
Groundwater lowering is one of the most important countermeasures to avoid the risk of rainfall-triggered landslides.However,the long-term reliability of many drainage methods is often a matter of concern since the dr...Groundwater lowering is one of the most important countermeasures to avoid the risk of rainfall-triggered landslides.However,the long-term reliability of many drainage methods is often a matter of concern since the drains may easily get clogged.A new hydraulic-driven self-starting drainage method is presented in this paper.In the proposed Random Forest(RF)based robust design approach for the selfstarting drains,the datasets are generated using an automatically controlled numerical modeling technology.The deterministic analysis is carried out based on uncertain soil parameters and the specific designs selected using Uniform Design(UD).The ensemble of RF models is applied in the design process to improve computing efficiency.Safety requirements,design robustness,and cost efficiency are simultaneously considered utilizing multiobjective optimization.A straightforward and efficient framework that focuses on difficulties caused by an enormous design space is established for the robust design of the self-starting drains,and improved computation efficiency is achieved.The effectiveness of the proposed approach is illustrated with a case study,the Qili landslide in Zhejiang Province,China.展开更多
基金financially supported by the National Key R&D Program of China (Grant No. 2018YFC1504704)the National Natural Science Foundation of China (Grant No. 41772276)Key R&D project of Zhejiang Province (Grant No. 2017C03006)
文摘The siphon drainage is an effective measure for the slope groundwater control. However,for the traditional siphon drainage, limitations such as siphon lift restriction and poor reliability in longterm service prevent it from being widely used. In this study, an improved siphon drainage method with inclined borehole penetrating the deep part of the slope is proposed to overcome the limitations suffered by the traditional method. Through experimental research, theoretical analysis and engineering practice,the reliability and capability of the proposed method are investigated. The results demonstrate that with the inclined pipe the height difference between the control point of the groundwater level and the orifice can be controlled to be less than the height of the water column corresponding to the local atmospheric pressure. As a result, deep drainage can be achieved.In addition, by controlling the diameter of siphon drainage pipe not larger than 4 mm, a plug flow can be formed in the siphon pipe, which can prevent air accumulation in the siphon process and a continuous and effective siphon drainage is achieved. Through a practical project running smoothly since September 2013, it is found that the proposed method can effectively drain the groundwater deep in the slope and the maximum drawdown of groundwater level in boreholes can reach 8.5 m with an average drainage flow of 5.5 m3/d. The practical results also illustrate that 4 mm siphon pipe can be used to realize deep slope drainage and restart siphon automatically.
基金Foundation item： Project（1220BAK10B06） supported by the National ＂Twelfth Five-Year＂ Plan for Science ＆ Technology Support Program of China Project（20100101110026） supported by the PhD Programs Foundation of Ministry of Education of China Project（2009RS0050） supported by the Key Innovation Team Support Fund of Zhejiang Province, China
文摘An optimal drainage tunnel location determination method for landslide prevention was proposed to solve the existing problems in drainage tunnel construction. Current applications of drainage tunnel systems in China were reviewed and the fimctions of drainage tunnel were categorized as catchment and interception. Numerical simulations were conducted. The results show that both catchment and interception tunnels have variation of the function in the simulation of monolayer model, which shows the reduction of permeability condition in lower layer. The function of catchment can be observed in the deep slope, while the function of interception is observed near groundwater source. By using the slope safety factor and discharge water amount as the objectives of optimal drainage tunnel location, and pore-water pressure in fixed node and section flux as the judgment for construction quality of adjacent drainage tunnel, the design principle of drainage tunnel was introduced. The K103 Landslide was illustrated as an example to determine the optimal drainage tunnel location. The measured drainage tunnel efficiency was evaluated and compared with that from the numerical analyses based on groundwater data. The results validate the present numerical study.
基金supported by the National Natural Science Foundation of China(Grant No.41772276)the Key R&D project of Zhejiang Province(Grant No.2017C03006)the Zhejiang University and the Norwegian Geotechnical Institute for funding his research stay at NGI。
文摘Groundwater lowering is one of the most important countermeasures to avoid the risk of rainfall-triggered landslides.However,the long-term reliability of many drainage methods is often a matter of concern since the drains may easily get clogged.A new hydraulic-driven self-starting drainage method is presented in this paper.In the proposed Random Forest(RF)based robust design approach for the selfstarting drains,the datasets are generated using an automatically controlled numerical modeling technology.The deterministic analysis is carried out based on uncertain soil parameters and the specific designs selected using Uniform Design(UD).The ensemble of RF models is applied in the design process to improve computing efficiency.Safety requirements,design robustness,and cost efficiency are simultaneously considered utilizing multiobjective optimization.A straightforward and efficient framework that focuses on difficulties caused by an enormous design space is established for the robust design of the self-starting drains,and improved computation efficiency is achieved.The effectiveness of the proposed approach is illustrated with a case study,the Qili landslide in Zhejiang Province,China.
