The first job for Texas Crane Services’ new GMK7550 all-terrain crane was a dam maintenance project in Bastrop County, TX. The 550-USt crane lifted a Grove RT530E-2 rough-terrain crane onto a barge. The RT-equipped barge then was used to replace stop logs on the dam of the Lake Bastrop reservoir.
The 4,000-ft. long, 85-ft. high earth-filled dam is inaccessible to cranes from land, which led San Antonio-based Texas Crane Services to plan the barge approach employing both the all-terrain and rough-terrain cranes.
Sterling Frymire, senior vice president for Texas Crane Services, said the uneven terrain and size of the dam required an innovative solution.
“We had a few meetings at the lake to determine how we could get a crane close enough to the dam to move the logs,” said Frymire. “Once we saw it was impossible to reach the dam from land, we decided to use the rough-terrain crane on the barge.”
The crane features a 197-ft. five-section boom and an 82- to 259-ft. optional luffing jib. For the pick, it worked at a 105-ft. radius. It was configured with 148 ft. of main boom and used 120 USt of counterweight to lift the 30-USt capacity rough-terrain crane.
Capacity was an obvious priority when selecting the GMK7550 to perform the lift. However, because of the nature of this job, working at a 105-ft. radius to place a heavy load, counterweight was also critical. The GMK 7550 is available with 264,500 lbs. of counterweight – all of which was used for this lift. The crane features a hydraulic counterweight installation and removal system, which improves rigging and set-up time.
Once the Grove RT530E-2 was placed on the barge, it was floated across the lake to the section of the dam that needed repair. Positioned next to the dam, the RT530E-2 was able to replace the logs safely and efficiently.