InSAR Technology Is Used For Fine Monitoring Of Linear Morphologies

There is a dense road network in North China,along which there is a lot of infrastructure.Land subsidence has a serious impact on road operation and traffic safety.Ground fracture disaster is also one of the main geological disasters in North China,which has caused huge economic and property losses.Among them,Beijing and Hebei are two areas in North China where the land subsidence and ground fracture disaster are more serious.Traffic lines,ground cracks and fractures are more typical linear bodies,such objects long distance,narrow width,large span,often distributed along the buildings and other infrastructure.Therefore,it is of great importance to monitor the stability of this type of linear body and master its deformation mechanism,activity law and spatial distribution in detail,which is of great importance to protect people’s life and property safety.As a new type of earth observation technology,Synthetic Aperture Rader(InSAR)technology has quickly become one of the important methods for earth observation due to its capability of obtaining the surface deformation information in a large range,all-weather and high precision.It plays an important role in the monitoring of geological disasters such as ground subsidence,ground cracks,earthquake and landslide.In this paper,the main traffic roads around Beijing Daxing International Airport,ground cracks near Beijing Capital International Airport and ground cracks and fractures near Longyao in Hebei province are taken as research objects.Based on Sentinel-1 ascending and descending images,the paper uses StaMPS and SBAS-InSAR technology to carry out monitoring.It provides technical support and theoretical basis for ground subsidence and ground fracture disaster monitoring in this area.The specific research contents and achievements of this paper are as follows:(1)The vertical deformation rate of the area around Beijing Daxing International Airport from 2019 to 2020 is obtained based on Sentinel-1 ascending and descending orbit images using StaMPS technology.The results show that there are several subsidence areas near the airport,and the deformation rate of some areas exceeds-30mm/yr.The time sequence results show that the cumulative shape variables of the three time sequence points in two years reach-58,-60and-70 mm respectively.The extracted deformation results and the deformation trend along the main roads in the study area show that there are different degrees of ground deformation on several main roads,and the maximum deformation rate of some sections exceeds-25mm/yr.(2)The vertical deformation rate of the area around Beijing Daxing International Airport from 2021 to 2022 is obtained based on Sentinel-1 elevated rail images using StaMPS technology.Compared with the results from 2019 to 2020,it can be seen that the subsidence of the west subsidence area of the airport slows down,while the ground subsidence near the northeast of the airport is still serious.The deformation results and deformation trend along the main roads in the study area showed that the maximum deformation rate of some sections of the main roads still exceeded-25mm/yr,especially the settlement area of the two sections of the Beijing-Taiwan Expressway.(3)Using StaMPS technology,the annual average vertical deformation rate of the area around Beijing Capital International Airport from 2017 to 2021 is obtained based on Sentinel-1 rising and descending images.The results show that there is a subsidence area in the south of the airport and the south of Yongding River,and the maximum annual deformation rate is more than-40mm/yr.The extracted time series results show that the land surface near Zaolin New Village is relatively stable,the land surface near Machuan village is slowly rising,and the settlement occurs in Jinzhan Township and Fufu Village.The deformation rate and cumulative deformation results of the airfield are extracted.The results show that the whole airfield has a differential deformation bounded by the ground fracture.The north side of the ground fracture is settling,while the south side is uplifting.(4)The StaMPS and SBAS-InSAR technology were used to obtain the deformation results of Longyao region in Hebei Province from 2017 to 2022 based on Sentinel-1 orbital images.The results show that there are many subsidence areas in the study area,among which the subsidence area around Julu County is larger;The extracted time series results show that Xinhe County and Longyao County are uplifted as a whole,Julu County is stable as a whole,and settling occurs near Ningjin County.The maximum cumulative shape variables are 210,90,-40 and-80 mm,respectively,while the maximum cumulative shape variables of Tuancheng village,Dicun Township and Guchengdian Town are-250,-170 and-160 mm,respectively.And the change trend of the temporal results showed a certain periodicity.The results of profile lines and time series on both sides of Longyao fracture and Xinhe Nangong fault show that the maximum deformation rate difference on both sides reaches 40mm/yr and 50mm/yr respectively.