Hysteretic Behavior and Strength Capacity of Shallow Embedded Steel Column Bases

摘要

A shallow embedded steel column base consisting of an exposed column base and a covering reinforced concrete (RC) floor slab is examined. A series of tests are conducted for shallow embedded steel column bases subjected to horizontal cyclic loading leading to very large deformations, and the effects of the floor slab on the strength and ductility are examined. By the adjustment of the floor slab thickness and shape, the elastic stiffness, maximum strength and dissipated energy of the shallow embedded column bases increases to 1.1 to 1.5, 1.4 to 2.0, and 1.1 to 2.1 times. Punching shear failure in the floor slab around the column is notable due to the uplift of the base plate. At the end of loading, the punched-out part is completely separated from the rest. Based on the plastic theory, a mechanical model that considers the contributions of the anchor bolts and the bearing and punching shear of the floor slab is proposed to evaluate the maximum strength. The evaluated results have good agreement with the test results, with errors not exceeding 20%.