Page 118 - Water Standards

AnnexA CalculationofPowerhouse
Stabilit ya g ainstDee pSeatedSlidin g

A.0.1 Whenlow-an g lestructural- p lanesexistintherockfoun-

dationofp owerhouse , thestabilit yanal y sisa g ainstdee pseated
slidin gma ybecarriedoutb ysimp lif y in gthemintosin g leslidin g
p lane, doubleslidin gp lanesandmulti p leslidin gp lanesaccordin g
tog eolo g icaldata.Thestabilit ya g ainstdee pslidin gofp ower-
houseonrockfoundationma ybecalculatedwiththeri g idbod y
limite q uilibriummethod,uedb ysafet yfactor , andshouldbe
jg
calculatedb yshearfrictionformula.Fordam monolithswhere
thecalculationwithshearfrictionformulacannotmeetthere-
q uirementsinTable5.3.4aftertakin gen g ineerin gmeasures ,
theirsafet yfactorsofslidin gstabilit yma ybecalculatedb yslid-
in g -frictionFormula ( A.0.2 2),Formula ( A.0.3 4) For-
mula ( A.0.3 6), andthecorres p ondin gallowablesafet yfactor
ma ybedeterminedafterstudies.
A.0.2 Ifthedee p -seatedslidin gp laneofp owerhousefounda-
tionisthesin g leslidin gp lane( seeFi g ureA.0.2), thesafet y
factorma ybecalculatedwiththefollowin gmethods :
1 Theshearfrictionformula.Theshearfrictionsafet yfac-
torofstabilit ya g ainstslidin gma ybecalculatedb ytheFormula
( A.0.2 1):

∑W
K′= f ′[( +G) cos α-∑Psin α-U] +c′A
∑W
( +G) sin α+∑Pcos α
( A.0.2 1)

0 1 1