Abstract
Fiber Bragg grating (FBG)–based fiber optic sensors are widely used in structural health monitoring because of their high sensitivity, electromagnetic immunity, and long-term operational stability. However, their performance is significantly affected by environmental factors, including temperature, humidity, installation quality, and material degradation, which reduce measurement accuracy under real operating conditions. This study aims to investigate the sensitivity of multi-point FBG sensors and to develop an integrated analytical framework for evaluating the combined influence of these factors on deformation monitoring in building structures. The proposed methodology combines analytical modeling based on Bragg wavelength theory, temperature compensation, strain-transfer analysis, and reliability assessment using Kaplan–Meier survival curves. Unlike previous studies that primarily examine these factors separately, the proposed approach integrates them into a unified sensitivity evaluation model. Numerical simulations and comparative analysis demonstrate that accounting for combined environmental effects improves the reliability and accuracy of deformation measurements while enabling optimization of sensor placement and long-term monitoring strategies. The obtained results provide practical recommendations for the design and implementation of fiber-optic structural health monitoring systems and contribute to improving the reliability of civil infrastructure monitoring under realistic service conditions.