Evaluación de la vulnerabilidad de edificaciones por subsidencia mediante datos InSAR (2022-2023) UPL Suba Sector Noroccidente

Abstract

Over the past few years, the city of Bogotá has experienced a significant increase in the percentage of buildings constructed under informal conditions. This is mainly because many structures were built without complying with current building regulations and/or were constructed by informal builders ("maestros de obra") rather than licensed engineers, resulting in increased structural vulnerability and risk. Consequently, one of the major challenges affecting these buildings is their potential risk of collapse or foundation settlement. The risk of collapse or settlement of a building also poses a threat to adjacent structures, as they may be significantly affected. If such events occur, they can cause severe structural damage, ground instability, mass movements, and progressive collapse of neighboring buildings, thereby endangering the safety of occupants and pedestrians. The use of Synthetic Aperture Radar (SAR) data and remote sensing techniques to assess land subsidence from space enables the measurement of ground deformation, specifically land settlement. Land subsidence often causes damage to urban infrastructure and buildings, including tilting, cracking, and other structural failures in constructions that interact directly with the ground. To address this issue, this monograph applies an interferometric processing methodology to estimate the vertical deformation of the ground during the 2022–2023 period. Based on the displacement vectors obtained, an interpolation mesh will be generated to calculate the angular distortion across building footprints. Subsequently, by implementing fragility curves adapted to local construction typologies, the probability of physical damage to buildings will be estimated. The monitoring of land subsidence, together with the obtained results, will enable the identification of critical areas and provide technical information to support risk management and sustainable urban planning. The main outcome of this research will be a thematic map of structural vulnerability at the cadastral predial scale, proposed as an innovative and cost-effective technical input for updating the physical component of the Multipurpose Cadastre in Bogotá. This approach will improve the identification of properties experiencing structural degradation while supporting institutional risk management and property valuation processes. Furthermore, the results will provide valuable information for identifying vulnerable areas, improving urban land management, and promoting more sustainable and resilient territorial development in response to the impacts of uncontrolled urban growth.