DeCordova Bend Dam GPR

The DeCordova Bend Dam forms the Lake Granbury Reservoir on the Brazos River southeast of Granbury, TX and was constructed between 1966 and 1969. In conjunction with other consultants, BDI performed concrete material sampling and a nondestructive evaluation (NDE) at select portions of the dam to facilitate operational and structural improvements to the dam. A portion of our NDE scope included 

• Ground Penetrating Radar (GPR) Testing: GPR testing was used to evaluate as-built reinforcing configuration of select concrete piers, concrete hoist platforms, and concrete bridge decks for the dam. GPR was also used to assess general concrete integrity in the vicinity of trunnion anchor bars at select concrete piers for the dam.

This project required a diverse set of certifications and expertise, including SPRAT rope access certification, specialized training and custom BDI-designed equipment for GPR testing in the vicinity of the trunnion anchor bars, experience with remote operation of GPR equipment with a robotic crawler, experience working from mobile elevated work platforms (MEWPs), and experience completing testing in the unique and challenging environmental conditions typical at dams. BDI’s team used rope techniques to access testing areas at concrete piers, MEWPs to access portions of the testing areas at bridge deck undersides, and ladders to access all other testing areas without walkup access. As-built reinforcing configuration data was generated for all test locations, and contour maps and statistical results for general concrete integrity were generated for the select concrete piers that were tested in the vicinity of the trunnion anchor bars.