Three-Dimensional Static and Dynamic Analysis of Structures
)U&9d A Physical Approach With Emphasis on Earthquake Engineering
C QkY6 Q]WBH_j by
UqK .b}s Edward L. Wilson
] A5F}wV4 Professor Emeritus of Structural Engineering
$$9H1)Ny University of California at Berkeley
cY?|RXNmZ m{IlRf' Copyright Computers and Structures, Inc., 1996-2001
V:\:[KcL^ The CSI Logo is a trademark of Computers and Structures, Inc.
&jDN6n3z SAP90, SAP2000, SAFE, FLOOR and ETABS are trademarks of
Mu3G/|t( Computers and Structures, Inc.
Z
RVt2 ISBN 0-923907-00-9
#C9f?fnM G5} _NS/ Preface To Third Edition
LU6R"c11 This edition of the book contains corrections and additions to the July 1998 edition.
DyC*nE ; Most of the new material that has been added is in response to questions and comments
+( LH!\{^ from the users of SAP2000, ETABS and SAFE.
o,7|=.-b Chapter 22 has been written on the direct use of absolute earthquake displacement
% 1 ?t)Bg loading acting at the base of the structure. Several new types of numerical errors for
Ip
t;NlR absolute displacement loading have been identified. First, the fundamental nature of
#V k? displacement loading is significantly different from the base acceleration loading
iOiF kka traditionally used in earthquake engineering. Second, a smaller integration time step is
&[G)Y D required to define the earthquake displacement and to solve the dynamic equilibrium
?C|'GkT equations. Third, a large number of modes are required for absolute displacement
[ V.6 7_~ loading to obtain the same accuracy as produced when base acceleration is used as the
01.q9AGy loading. Fourth, the 90 percent mass participation rule, intended to assure accuracy of
;Q{D]4 the analysis, does not apply for absolute displacement loading. Finally, the effective
a 0SZw modal damping for displacement loading is larger than when acceleration loading is
" MnWd BS used.
lR?y
tIY To reduce those errors associated with displacement loading, a higher order integration
%]P{)*y-? method based on a cubic variation of loads within a time step is introduced in Chapter
iv*RE 9?^ 13. In addition, static and dynamic participation factors have been defined that allow the
- Jaee,P structural engineer to minimize the errors associated with displacement type loading. In
M5I`i{Gw addition, Chapter 19 on viscous damping has been expanded to illustrate the physical
um9&f~M effects of modal damping on the results of a dynamic analysis.
E QyX! Appendix H, on the speed of modern personal computers, has been updated. It is now
ZqclmCi possible to purchase a personal computer for approximately $1,500 that is 25 times
A/y|pg5 faster than a $10,000,000 CRAY computer produced in 1974.
Wl| i$L)7 Several other additions and modifications have been made in this printing. Please send
,^9+G"H:I your comments and questions to
ed@csiberkeley.com.
c.>f,vtcn Edward L. Wilson
VY6G{f April 2000
