Three-Dimensional Static and Dynamic Analysis of Structures
#)my)}o\p A Physical Approach With Emphasis on Earthquake Engineering
| +suGqo Da?0 B9' by
r/:9j(yxr Edward L. Wilson
+&(sZFW5o Professor Emeritus of Structural Engineering
+ #S]u C University of California at Berkeley
I BES$[ <ywxz1 i Copyright Computers and Structures, Inc., 1996-2001
~uzu* 7U The CSI Logo is a trademark of Computers and Structures, Inc.
/3FC@?l
w4 SAP90, SAP2000, SAFE, FLOOR and ETABS are trademarks of
:L*CL 8m Computers and Structures, Inc.
"N7C7`izc ISBN 0-923907-00-9
m[ifcDZ( e nzhQ\' TC Preface To Third Edition
*5*d8;@ > This edition of the book contains corrections and additions to the July 1998 edition.
BIw9@.99B- Most of the new material that has been added is in response to questions and comments
G]QD6b9~ from the users of SAP2000, ETABS and SAFE.
\DeZY97p% Chapter 22 has been written on the direct use of absolute earthquake displacement
B<8Z?:3YS loading acting at the base of the structure. Several new types of numerical errors for
90K&s#+13 absolute displacement loading have been identified. First, the fundamental nature of
8Ln:y'K displacement loading is significantly different from the base acceleration loading
8$?a?7,>| traditionally used in earthquake engineering. Second, a smaller integration time step is
Vu~mi%UH required to define the earthquake displacement and to solve the dynamic equilibrium
#FTXy >W equations. Third, a large number of modes are required for absolute displacement
`=q)-y_C loading to obtain the same accuracy as produced when base acceleration is used as the
]7h&ZF loading. Fourth, the 90 percent mass participation rule, intended to assure accuracy of
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the analysis, does not apply for absolute displacement loading. Finally, the effective
>"zSW? modal damping for displacement loading is larger than when acceleration loading is
i` Lt=)@& used.
M ;\K+, To reduce those errors associated with displacement loading, a higher order integration
( Pvch! method based on a cubic variation of loads within a time step is introduced in Chapter
z Lf^O%zN 13. In addition, static and dynamic participation factors have been defined that allow the
Ms{v;fT structural engineer to minimize the errors associated with displacement type loading. In
o#%2N+w addition, Chapter 19 on viscous damping has been expanded to illustrate the physical
R%7k<1d'` effects of modal damping on the results of a dynamic analysis.
8I @= ? Appendix H, on the speed of modern personal computers, has been updated. It is now
ZiVT c/b possible to purchase a personal computer for approximately $1,500 that is 25 times
DX4
95<6* faster than a $10,000,000 CRAY computer produced in 1974.
Rjm5{aa- Several other additions and modifications have been made in this printing. Please send
t)$>++i your comments and questions to
ed@csiberkeley.com.
~l {CUQU Edward L. Wilson
D?X97jNm April 2000
