NONDESTRUCTIVE CONDITION ASSESSMENT OF CONCRETE RAILROAD TIES Paul Fisk, NDT Corporation
CORPORATION Nondestructive Concrete Testing Services 18 Years-600+ projects Developed Sonic/ultrasonic NDT Equipment
BACKGROUND Union Pacific Railroad Call Test Out of Service Ties Test Siding Ties Test Plymouth Commuter Rail Comparison of Impact Velocity Results with AMTRAK Rating
Impact Velocity and Echo Measurements Impact Velocity Measurements Compressional, Shear and Surface Wave Velocity Moduli Values Average Dynamic Strength Crack Density Impact Echo Measurements Thickness Delaminations
Impact Velocity Impact Echo
Properties Detected by SONIC/ULTRASONIC Testing Velocity Concrete Condition (strength, cracking) Thickness Resonant Frequencies Thickness Delamination Signal Attenuation Sample Test Data
CONCLUSION Sonic/ultrasonic results can be used to evaluate and document the current condition of concrete railroad ties Ties can be classified as Functional Marginally Functional-should be retested in the near future Non-Functional- take out of service
Automated Testing Estimated 1 tie per sec
SUMMARY Sonic/ultrasonic pulse velocity data can be used to evaluate and document the current condition of concrete railroad cross ties Ties classification correlates with systems currently used by rail roads Automated Sonic/ultrasonic data acquisition is fast (1 sec/tie)
QUESTIONS ????