Study On Risk Assessment And Control Measures Of Debris Flow At Chengbei Gully In Ji County

Chengbei Gully is located at the north part of Ji County Shanxi Province.This area is on the south side of Luliang Mountain and west of the Yellow River.The area has a high density of valleys and serious soil erosion.It is one of the most developed mudslide areas in Shanxi Province.Because of the limitations of construction land,“developing toward the mountains and developing toward the ditch”has become a trend,which has caused many geological disasters.Landslides and collapses are also serious here.These geological disasters pose great potential hazards to the residents' life and property.It is necessary to investigate and study this question,and put forward risk prevention measures for high-risk debris flow.Based on the field investigation and data collection,this paper studied the characteristics of debris flow in Chengbei Gully.The FLO-2D software was used to simulate the process of debris flow.Simulation results show the distribution of accumulation range,deposition depth and flow velocity of Chengbei debris flow.On this basis,a dangerous zoning was carried out.Combining the numerical simulation results with“method of comprehensive risk assessment of debris flow disaster risk”,we made an assessment of the life risk and economic risk.Then,we got comprehensive risk of debris flow in Chengbei Gully.The F-N curve is used to determine the risk level in Chengbei Gully as “ Tolerable Risk”.And it is recommended to adopt the “risk reduction” management method for the gully.Afterwards,we decided to design two barrier dams and follow the existing drainage channels.We calculated the cost of the project for 2.5259 million yuan.Finally,We used the principle of cost-benefit analysisb.to evaluate the risk management benefits of engineering measures.We obtained the absolute benefit of this program is 80.993 million yuan,and the relative benefit of risk management is 4.21.Therefore,we believe that the program is economically reasonable,technically feasible,and safe and reliable.The study uses high-precision DEM terrain data in numerical simulation,which makes the risk analysis of debris flow closer to reality.The use of“Comprehensive risk assessment method for debris flow disasters ” makes the assessment of risk and the decision of riskmanagement methods more scientific.After calculating the budget for risk mitigation measures,we can use the principles of cost-benefit analysis to derive risk management benefits.