Enhanced integral form of the Newmark time stepping scheme for pseudodynamic testing

A novel integral form time-integration algorithm for pseudodynamic testing is proposed, based on the Newmark implicit algorithm. The scheme builds on the recently proposed integral form of the Newmark explicit algorithm which exhibits improved abilities to handle rapidly varying loads and stiffness properties during pseudodynamic testing, but displays some numerical dampin g and conditional stability. Thc enhancement is based oi? the inclusion of an additional term in the displacement predictor, which not only renders th e algorithm more consistent, but it eliminates numerical damping and makes the algorithm unconditionally stable.