Abstract
Abstract. The stability control is one of the major technical difficulties in the field of highway subgrade construction engineering. Building deformation model is a crucial step for InSAR time series deformation monitoring. Most of the InSAR deformation models for deformation monitoring are pure empirical mathematical models, without considering the physical mechanism of the monitored object. In this study, we take rheology into consideration, inducing rheological parameters into traditional InSAR deformation models. To assess the feasibility and accuracy for our new model, both simulation and real deformation data over Lungui highway (a typical highway built on soft clay subgrade in Guangdong province, China) are investigated with TerraSAR-X satellite imagery. In order to solve the unknows of the non-linear rheological model, three algorithms: Gauss-Newton (GN), Levenberg-Marquarat (LM), and Genetic Algorithm (GA), are utilized and compared to estimate the unknown parameters. Considering both the calculation efficiency and accuracy, GA is chosen as the final choice for the new model in our case study. Preliminary real data experiment is conducted with use of 17 TerraSAR-X Stripmap images (with a 3-m resolution). With the new deformation model and GA aforementioned, the unknown rheological parameters over all the high coherence points are obtained and the LOS deformation (the low-pass component) sequences are generated.
Highlights
Roads and highways built on soft clay subgrade are more prone to subsidence and induced instability
According to the literatures published, we found most of the InSAR deformation models for deformation monitoring are pure empirical mathematical models (Yu, 2013; Dong, 2014; Kim, 2010; Hetland, 2012), without considering the physical mechanism of the monitored object
After investigation on the relationship between SAR length of sight (LOS) deformation and strain in Kelvin model, we obtain the mathematical function for LOS surface deformation with parameters of viscosity, elasticity modulus and time, the time series set of SAR phase functions can be established
Summary
Roads and highways built on soft clay subgrade are more prone to subsidence and induced instability. Monitoring long-term surface deformation of highways on soft clay subgrade is crucial for understanding the dynamics of the settlement process and preventing potential hazards(Ge, 2008). If we take rheology into consideration, inducing rheological parameters into traditional InSAR deformation models, the accuracy of long-term deformation monitoring can be greatly increased, and the interpretation for the estimated deformation be more reasonable. In order to improve the accuracy of longterm deformation monitoring after highway embankment settlement construction, and interpret the displacement result more reasonably, we establish a new InSAR time series deformation model. After investigation on the relationship between SAR LOS (line of sight) deformation and strain in Kelvin model, we obtain the mathematical function for LOS surface deformation with parameters of viscosity, elasticity modulus and time, the time series set of SAR phase functions can be established
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
