Dr. Jorj O. Osterberg, Professor Emeritus of Civil Engineering at Northwestern University, invented and developed a deep foundation load testing device to meet the construction industry’s need for an innovative effective method for testing high capacity drilled shafts and piles. Osterberg’s invention, the Osterberg Cell, commonly called the “O-cell” by the industry, has radically changed the way foundation load tests are designed, performed and interpreted.

The O-cell is a hydraulically driven, high capacity, sacrificial jacking device installed within the foundation unit. Working in two directions, upward against side-shear and downward against end-bearing, the O-cell automatically separates the resistance data.

By virtue of its installation within the foundation member, the Osterberg Cell load test is not restricted by the limits of overhead structural beams and tie-down piles. Instead, the O-cell derives all reaction from the soil and/or rock system. End bearing provides reaction for the side shear portion of the Ocell load test, and side shear provides reaction for the end bearing portion of the test. Load testing with the O-cell continues until one of three things occurs: ultimate side shear capacity is reached, ultimate end bearing capacity is reached, or the maximum O-cell capacity is reached.

Loadtest specializes in bi-directional deep foundation load testing using the award winning Osterberg cell. Founded in 1991 they have conducted over 600 load tests, redefining the Art of Load Testing along the way.