Flyover Video by Delaware DOT of this interchange at 4:18:
the mating surface between the disc and the steel is un-coated to increase the friction between the ribbed disc material and the steel, preventing surface expansion
Project Description
This is the 1st major phase of a $470M project to link US 301 at the Maryland line SW of Middletown and SR 1 between the Biddles Toll Plaza and the Roth Bridge over the Chesapeake & Delaware Canal. 33 Disktron Expansion and Fixed Bearings were installed. Strength vertical load varied from 200 Kips to 3650 Kips with a typical rotation of 0.03 radians. Strength horizontal loads varied between 10% to 25% of the strength vertical load. Longitudinal displacement for the expansion bearings varied from 2.50″ to 4.75″ of total displacement.
TESTING: RJ Watson’s High Load Test Frame was able to perform the standard production testing for the project. The expansion bearings were for a large concrete cross girder with a design load capacity of 2910 kips. The limited plan size of the pier required a large rectangular plan area with two discs side-by-side to support the required loads and provide added overturning resistance. RJ Watson performed the required proof load test to 4365 kips (150%) with a simultaneous rotation of 0.02 radians using our large 9.5 Million lb compression test machine. A friction test was also performed using RJ Watson’s 600 kip rated actuator and load cell. Test control and data collection was done with our Pacific Instruments data acquisition system for analysis and reporting. Post-testing Inspection was performed and the bearings were later released for use on the project.
