Integrated Mems-Based Vibration Monitoring And Diagnostic Index Framework For Structural Health Monitoring And Seasonal Assessment Of The Bhakta Kannappa Sethu Bridge In Srikalahasthi

Abstract

Ensuring the structural safety of aging bridges, particularly in resource-limited regions, is crucial for long-term resilience. This study proposes a low-cost Structural Health Monitoring (SHM) system using MEMS accelerometers and ESP32 microcontrollers, implemented on the Bhakta Kannappa Sethu Bridge in Srikalahasti. Over twelve months, vibration responses were recorded under four traffic load conditions. From these, four diagnostic indices - Normalized Dynamic Index (NDI), Dynamic Performance Ratio (DPR), Stiffness Degradation Index (SDI), and Health Stability Index (HSI) were developed using June as the baseline.The results revealed seasonal and load-dependent variations. High DPR values in March and December signified increased dynamic activity. SDI values below 1 in August and May indicated mild stiffness reductions, while elevated HSI in July (Peak Load: 46.89) reflected structural stability. Conversely, low HSI in December and March suggested dynamic irregularities during colder periods.This framework demonstrates that affordable SHM systems, combined with intelligent indices, can deliver continuous diagnostics, early warnings, and long-term insights offering a scalable solution for bridge monitoring in constrained environments.