Developing and applying a new PS-InSAR method to measure the nonlinear behavior of structures and infrastructure facilities

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H02411
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 25030:Disaster prevention engineering-related
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Matsuoka Masashi 東京工業大学, 環境・社会理工学院, 教授 (80242311)
• Co-Investigator(Kenkyū-buntansha): 三浦 弘之 広島大学, 先進理工系科学研究科(工), 准教授 (30418678) ; 劉 ウェン 千葉大学, 大学院工学研究院, 助教 (60733128)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 人工衛星 / 合成開口レーダ / 時系列干渉処理 / 2πアンビギュイティ / 数値シミュレーション / 地盤沈下 / 構造物被害

Outline of Final Research Achievements

The PS-InSAR method has had difficulty in estimating large-scale or nonlinear displacements in urban areas, but, in this study, we proposed a new method (NN-PSI), in which the height of the object is estimated from the cumulative values of time series coherence in the displacement velocity direction, and the displacement of the object is calculated by superposing the phase difference of all displacement velocities of the observation condition with the determined height, weighted by the time series coherence. Numerical simulations with various deformation patterns and observed parameters were conducted, and the estimation accuracy and applicability limits were verified by applying the method to actual data obtained from buildings and ground observations. The relationship between coherence and damage to structures and lifelines caused by earthquakes is also discussed.

Free Research Field

リモートセンシング

Academic Significance and Societal Importance of the Research Achievements

高度経済成長期に建設され長期間にわたって利用されてきた施設には老朽化したものが多く，その維持管理が喫緊の課題になっている，例えば，変形の計測には多大なコストと労力がかかり管理者の負担になっており，リモートセンシング技術への代替が期待されている。本研究は都市域における施設や地盤について，人工衛星の時系列InSAR手法ではこれまで計測が不可能であった非線形的で大規模な変位を計測することを可能にしたものであり，社会的な意義がある。