Model o he seismic analysis o a ch dams including in e ac ion e ec s
J. Dominguez
Unil'e sidad de Se illa. Spain
O.Maesa
Unii'e sidad de Las Palmas de G an Cana ias. Spain
ABSTRACT: A h ee-dimensional bounda y elemen model o he seismic analysis
o a ch dams is p esen ed. The soil and he dam a e assumed o be iscoelas ic
domains he o me being boundless. The wa e is assume o be comp essible
subjec o small ampli ude mo ions. The h ee domains a e disc e ized in o
B ."E. in a single model which includes a igu ous ep esen a ion o he
dam- ounda ion ock in e ac ion, he wa e - ounda ion ock in e ac ion and he
a eling wa e e ec s. The esponse o an a ch dam (The Mo ow Poin dam) o
ha monic wa es p opaga ing e ically is s udied. The impo an in luence o
he abo emen ioned in e ac ion and a eling wa e e ec s is clea ly shown by
compu ed esul s. These esul s a e in con as wi h so ne ob ained by o he
au ho s using a F.E. model.
1 INTRODUCTION
The analysis o he seismic esponse
o dam- ese oi sys ems is an
impo an p oblem wi hin he ield o
ea hquake enginee ing. The seismic
esponse can no be s udied
conside ing he s uc u e as an
isola ed body unde he in luence o a
uni o m base mo ion. The e a e
impo an e ec s due o he space
dis ibu ion o he exci a ion, he
dam-wa e , dam- ounda ion and
wa e - ounda ion in e ac ion, ha
make necessa y he use o models
including he h ee media and he
in e ac ion be ween hem. A g ea ·
e o has been dedica ed o his
subjec in he las �o decades. The
s udies o Hall and Chop a (1983) and
Fok and Chop a (1986) who analysed he
signi icance o a numbe .o ac o s
con ibu ing o he esponsee shold be
men ioned. Those s udies ha e been
done using he Fini e Elemen Me hod.
The model o Fok and Chop a (1986} led
o an ex ao dina y ad ance in he
ea hquake analysis o a ch dams.
Howe e i s ill con ains impo an
simpli ica ions which may gi e ise o
un ealis ic esul s. I 's main
simpli ying assump ions and
limi a ions a e:
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a) The model includes a massless
ounda ions which is only jus i ied
by he necessi y o ep esen ing a
boundless complian ounda ion using
a ini -e inodel. The soil-s uc u e
in e ac ion is no p ope ly
ep esen ed and he a eling wa e
e ec s can no be aken in o
accoun . Ve y ecen ly Zhang and
Chop a (1991) ha e s a ed o
analyse an al .e na i e o his model
o · he ounda ion using a
wo-dimensional bounda y �n eg al
o mula ion combined wi h a Fou ie
expansion.
bl A bo om abso ion coe icien
is u sed o ep esen he
wa e - ounda ion in e ac ion. I is
based on he one dimensional
. ep esen a ion o he wa e
é lec ion be ween he wa e and a
uni o m hal -space.
e) The model does no ake in o
accoun he jo in
wa e - ounda ion-dam in e ac ion.The
model o · he oúnda ion ock used
o he in e ac ion wi h he dam is
independen o ha used o he
wa e - ounda ion ock in e ac ion.
d) The assump ion o an uni o m
c oss · sec -ion ex ending om he
icini y o he dam o i� ini y may