Computer Program Series for Nonlinear Dynamic Analysis of Three-Dimensional Base Isolated Structures

3D-BASIS is a series of special purpose computer programs designed to analyze structures with nonlinear base isolation devices subjected to seismic motion. The series evolved from analysis of simplified structural models represented by condensed formulations (“stick representation”), to more elaborated structural models of components such as building columns, beams, walls, and water containers, combined in complex structural systems.

The program was developed to enable analysis of various isolation devices such as elastomeric bearings with low and high damping characteristics, sliding bearings, linear springs with complementary damping devices such as viscous fluids, viscoelastic, friction, and others, under realistic three-dimensional seismic motion.

The program series, which includes 3D-BASIS, 3D-BASIS-M, 3DBASIS-ME and 3D-BASIS-TABS, was distributed to the engineering and to the academic communities. These programs enabled analysis and design of complex structures and advanced the practical application of base isolation in seismic areas (both in the U.S. and overseas).

The program is distributed free, with corrections and minor updates, as part of a membership in a Users Group. For information on membership check the appropriate button above. Non-members can also get a version of the program executable free without any support.

The purpose of this web site is to keep you up to date on the latest reports, enhancements, memberships, as well as to help you resolve any problems you may encounter while using 3D-BASIS.