Three-Dimensional Static and Dynamic Analysis of Structures
OF c\fW# A Physical Approach With Emphasis on Earthquake Engineering
Og,Y)a;= sX +`wc by
kOw=c Gt Edward L. Wilson
^_v[QV Professor Emeritus of Structural Engineering
AY#wVy University of California at Berkeley
b2N6L2~V 6X/wd k Copyright Computers and Structures, Inc., 1996-2001
yL0f1nS The CSI Logo is a trademark of Computers and Structures, Inc.
Q,{^S,s< SAP90, SAP2000, SAFE, FLOOR and ETABS are trademarks of
RFw(]o,9cR Computers and Structures, Inc.
Z&_y0W=t ISBN 0-923907-00-9
4&Byl85q !c% Preface To Third Edition
lC0~c=?J This edition of the book contains corrections and additions to the July 1998 edition.
w/ TKRCO3 Most of the new material that has been added is in response to questions and comments
l , ..5 from the users of SAP2000, ETABS and SAFE.
{Fbg]'FQ Chapter 22 has been written on the direct use of absolute earthquake displacement
8 z Y)J # loading acting at the base of the structure. Several new types of numerical errors for
.*BA 1sjE absolute displacement loading have been identified. First, the fundamental nature of
3KSpB;HX displacement loading is significantly different from the base acceleration loading
(a[.vw^g traditionally used in earthquake engineering. Second, a smaller integration time step is
&5?G-mn required to define the earthquake displacement and to solve the dynamic equilibrium
bW53" `X equations. Third, a large number of modes are required for absolute displacement
v ? L loading to obtain the same accuracy as produced when base acceleration is used as the
MDJc[am loading. Fourth, the 90 percent mass participation rule, intended to assure accuracy of
"!O 1j
r; the analysis, does not apply for absolute displacement loading. Finally, the effective
|^R*4;Phe modal damping for displacement loading is larger than when acceleration loading is
bmu6@jT used.
[F+(^- ( To reduce those errors associated with displacement loading, a higher order integration
~g6"'Cya?k method based on a cubic variation of loads within a time step is introduced in Chapter
LheFQ A 13. In addition, static and dynamic participation factors have been defined that allow the
nX|Q~x] structural engineer to minimize the errors associated with displacement type loading. In
+b^ ]Pz5 addition, Chapter 19 on viscous damping has been expanded to illustrate the physical
2 nv[1@M effects of modal damping on the results of a dynamic analysis.
5F2_xH$5 Appendix H, on the speed of modern personal computers, has been updated. It is now
i}v9ut]B possible to purchase a personal computer for approximately $1,500 that is 25 times
zh\ $t]d<I faster than a $10,000,000 CRAY computer produced in 1974.
bN GCOj Several other additions and modifications have been made in this printing. Please send
[)^mBVht your comments and questions to
ed@csiberkeley.com.
lwc5S `" Edward L. Wilson
MaO"#{i April 2000
