Structural Health Monitoring (SHM) is important for the prevention and detection of corrosion, leaks and other damage types that could compromise their pose significant environmental, structural integrity and safety risks. This simulation work concentrates on the SHM of underground pipelines using polyimide coated LPFG-FBG-LPFG sensors; this simultaneous modeling focuses on temperature and pressure sensitivity effects. By using MATLAB coding, this work studies and investigates the sensors performance and modeling techniques. The sensitivity of temperature was calculated to be 3.7 nm/°C. While the pressure sensitivity was calculated to be 5.3 nm/Pa. The proposed sensor shows good linearity behavior and the coefficients of determination were found to be 0.9939 and 0.9878 for temperature and pressure sensors, respectively. The main findings of the current work demonstrate that the polyimide coated LPFG-FBG-LPFG sensors are highly sensitive and stable, making them suitable for long-term monitoring of pipeline structural health. The proposed simultaneous modeling regarding temperature and pressure effects by using MATLAB coding provides a reliable and accurate approach for diagnosing and detecting and pipeline anomalies. This model will enable the real time detection and diagnosis of underground pipelines damage or leaks, hence enhancing their safety, reliability, and reducing costs of maintenance aspects.
