Deformation Monitoring And Risk Assessment Of Dam Slope Based On Ground-based Radar Interferometry

Slope landslide disaster is a typical geological disaster.China's topographic and landform conditions are complex,frequent extreme climates occur frequently,high-intensity seismic activities are frequent,and various projects have damaged the geological environment,and other factors have exacerbated the occurrence of slope landslide disasters.So slope deformation monitoring has become a hot topic and a difficult issue for research in world.Because the traditional monitoring methods have certain limitations,they cannot satisfy the needs of slope deformation monitoring.Ground-based radar interferometry has the characteristics of all-day,all-weather monitoring,short monitoring period,and unaffected by terrain visibility and climatic conditions,It is suitable for two-dimensional non-contact deformation monitoring of the ground surface in the slow deformation stage of large-scale areas,the monitoring accuracy is high,and the accuracy can reach millimeter to sub-millimeter level.So the technology can be widely used in slope deformation monitoring,geological disaster prevention,and other fields.The main research contents of this paper are as follows:(1)Application of ground-based radar interferometry in slope deformation monitoring.This paper took the Hongshiyan slope monitoring project in Yunnan as an example.And obtained slope monitoring data at different time scales such as monthly,weekly,and daytime to quantitatively analyzed the dam stability.The experimental conclusions are as follows.Under normal circumstances,the deformation of the slope is relatively stable,and its deformation range is within 15 mm,and its deformation range is from-15 mm to + 15 mm.Affected by heavy rainfall during the flood season,the slope is in an unstable state,the deformation is in the range of-30 mm to + 25 mm,the deformation amplitude exceedes 15 mm and the maximum amplitude can reach 30 mm,and the slope is more likely to collapse.This method effectively proves the practicability of ground-based radar systems in the monitoring process.(2)Inadequating objectivity for traditional slope risk assessment methods,this paper presented a slope risk evaluation method based on the improved Bayes-weighted average method.The Bayesian network method was used to objectively analyze the subjective weights of the indicators and the fuzzy comprehensive evaluation method was used to quantitatively analyze the risk,this method effectively combined human subjective weight with objective weight,thus it reduced the subjectivity of indicator weights.Through experiments,the probability of the occurrence of slope risk from January to June 2019 is obtained,which provides a reference basis for earthquake prevention and disaster reduction of the projecct.