Bridge Health Monitoring Engineering triumph in the Udhampur-Srinagar-Baramulla Rail Link (USBRL) Project

The USBRL project is a landmark initiative aimed at connecting the Kashmir Valley with the rest of India through a reliable rail network. Within this extensive project, two bridges – Bridge No. 39 over Sulla Khad Nalla and Bridge No. 43 adjacent to the Chenab Bridge – stand out as engineering marvels. These bridges are equipped with state-of-the-art structural health monitoring systems implemented by PMT Infrascience Pvt. Ltd., ensuring their safety, longevity, and performance.

Bridge No. 39:

An Engineering Feat

Bridge No. 39 spans approximately 490 meters with a span arrangement of 1×53.15 + 6×64.0 + 1×53.15 meters, supporting a double-line Reasi station yard. The bridge features continuous composite steel girders, and its construction involved massive efforts, including 7.5 lakh cubic meters of earthwork, 36,500 cubic meters of concrete, 7,000 metric tons of reinforcement steel, and 7,552 metric tons of structural steel. The height of its piers ranges from 35.08 meters to 90.53 meters, with Pier P5 being the tallest. Stress was encountered in this region.

Bridge No. 43:

Structural Ingenuity

Bridge No. 43 extends 777 meters with a span arrangement of 1×35 + 1×53 + 10×64 + 1×49 meters and accommodates the Salal station yard. Like Bridge No. 39, it features continuous composite steel girders, with 490 meters of the bridge being straight and 287 meters curved. The construction of this bridge required 4 lakh cubic meters of earthwork, 36,948 cubic meters of concrete, 5,862 metric tons of reinforcement steel, and 7,920 metric tons of structural steel. A notable aspect is its unique hybrid well foundation with a diameter of 14 meters, stabilized with 153 micropiles to ensure structural integrity on steep slopes.

These systems not only ensure the safety and durability of the bridges but also set a benchmark for future infrastructure projects, highlighting the importance of advanced monitoring technologies in maintaining critical infrastructure

Structural Health Monitoring Systems

PMT Infrascience has implemented comprehensive structural health monitoring systems on both bridges to ensure their safety and performance. These systems utilize a variety of sensors to continuously monitor the structural integrity and environmental conditions affecting the bridges.

1. Static Strain Gauges: These sensors measure the strain on the steel girders, providing data on the stress and deformation experienced by the bridge under static loads.
2. Dynamic Strain Gauges: For measuring strain on the piers, providing data on the structures’ responses to dynamic loads.
3. Accelerometers (2D and 3D): These devices track vibrations in two and three dimensions, detecting any unusual movements or vibrations that could indicate structural issues.
4. Tiltmeters: These sensors measure the inclination of the piers, helping to detect any tilting or shifting that could compromise the bridge’s stability.
5. Automatic Weather Stations: These monitor environmental factors like wind speed and direction. A key feature is the system’s integration with the railway’s signaling and telecommunication system, which automatically halts rail traffic if wind speeds exceed 25 m/s, preventing accidents during high winds.
6. Advanced Alert Generation System: The monitoring system is equipped with an advanced alert generation feature. Any abnormal activity detected by the sensors triggers automatic alerts via email and text messages to authorized personnel, enabling swift response and mitigating potential risks.

The sensors are integrated with dynamic data acquisition systems, capturing data at high sampling rates to assess the structural response under various conditions. This data is continuously transmitted to a dedicated control room where it is visualized and analyzed by experts to maintain the structural health of the bridges.

Benefits of Structural Health Monitoring

The monitoring systems offer several compelling benefits:

• Enhanced Safety: Continuous monitoring detects potential issues early, allowing for prompt intervention and ensuring the safety of the structures and users.
• Cost Savings: Early detection of structural problems enables timely maintenance, preventing costly, extensive repairs and reducing overall maintenance expenses.
• Prolonged Lifespan: Regular monitoring and maintenance extend the bridges’ lifespan, ensuring they remain safe and functional for many years.
• Regulatory Compliance: These systems help meet all relevant safety and inspection regulations, providing peace of mind to operators and users while enhancing the credibility of the managing authorities.
• Improved Maintenance Planning: Detailed data on structural health allows for precise maintenance planning, reducing downtime and ensuring efficient use of resources.
• Enhanced Structural Understanding: Data from these systems offer valuable insights into the bridges’ behavior under various conditions, informing better design and construction of future infrastructure projects.
• Environmental Monitoring: Tracking environmental factors like wind speed and temperature helps mitigate adverse effects, ensuring safe and efficient operations.
• Increased Public Confidence: Advanced monitoring systems boost public confidence in the safety and reliability of the bridges, encouraging higher usage and support for further infrastructure investments.