Introducing Oscar the Oscillator

Oscar Intro

Oscar the Oscillator will help build an earthquake-ready Abernethy Bridge.

Construction is continuing on pace for the I-205 Improvements Project, and the crew is preparing for the arrival of the world’s most powerful steel casing oscillator, affectionately nicknamed Oscar. This piece of equipment is vital to building a safer, earthquake-ready Abernethy Bridge, enabling I-205 to be a lifeline route after a disaster.

Making the Abernethy Bridge earthquake-ready means the bridge will need to sit atop new supporting columns that are anchored in hard, solid bedrock located deep under the Willamette River—and this is where Oscar comes in. Oscar has a powerful motor that develops tremendous torque that is used to rotate, or oscillate, and simultaneously push, large cylindrical pieces of steel, called casings, into the ground.

As these casings are inserted, the soil within them is removed by a large crane and digging bucket. The resulting shafts are then filled with steel rebar cages and concrete to form new bridge foundations. As Oscar’s work progresses, the new columns will become visible as they increase in height and emerge from the water. Oscar has the most powerful hydraulic rams for an oscillator in the world, which means he can dig into bedrock with force and precision. 

Thanks to Oscar’s work, the Abernethy Bridge will be anchored in seismically-stable bedrock.

A few fun things about Oscar and his work: 

  • He weighs 200,000 pounds, equivalent to 26 elephants the size of Samudra at the Oregon Zoo.
  • He will drill a total of 28 shafts, allowing the construction of new support columns for the widened Abernethy Bridge. Some of these shafts will extend more than 200 feet below the Willamette River, equivalent to the height of the Oregon Convention Center spires, or 20 basketball hoops stacked on top of each other.

Oscar recently arrived in Tacoma, Washington via the Panama Canal. He traveled 9,070 nautical miles to reach the United States. The German manufacturing company Leffer built Oscar to serve as the mighty operating oscillator. He was shipped in seven containers and will travel by truck to the Oregon City worksite for assembly.

Once Oscar is finished working on the Abernethy Bridge, he will be packed up and sent to his next job.

Follow ODOT's FacebookInstagram and Twitter for updates on Oscar. We ask the public to stay safe and watch the I-205 construction from a safe distance.

As a reminder, this project's size and complexity will result in periodic road closures, detours, and other impacts, so please sign up for text messages and email alerts to stay informed or visit TripCheck