CSI Analysis Reference Manual For SAP2000®, ETABS®, and SAFE

Introduction
SAP2000, ETABS and SAFE are soft ware pack ages from Computers and Struc –
tures, Inc. for structural analysis and de sign. Each package is a fully in te grated sys –
tem for modeling, analyzing, de signing, and optimizing structures of a par tic u lar
type:

• SAP2000 for gen eral struc tures, in clud ing bridges, sta di ums, tow ers, in dus trial
plants, off shore struc tures, pip ing sys tems, build ings, dams, soils, ma chine
parts and many oth ers
• ETABS for build ing struc tures
• SAFE for floor slabs and base mats

At the heart of each of these soft ware pack ages is a com mon anal y sis en gine, re –
ferred to through out this man ual as SAP2000. This en gine is the lat est and most
pow er ful ver sion of the well-known SAP se ries of struc tural anal y sis pro grams.
The pur pose of this man ual is to de scribe the fea tures of the SAP2000 anal y sis en –
gine.

Through out this man ual the anal y sis en gine will be re ferred to as SAP2000, al –
though it ap plies also to ETABS and SAFE. Not all fea tures de scribed will ac tu ally
be avail able in ev ery level of each pro gram.