Page 93 - Water Standards

1 Reinforcedconcretearchribforcrown.
2 Full yenclosedreinforcedconcretelinin gforcrown,no
linin gorthinla y erconcretelinin gforsidewall.
3 Reinforcedconcretelinin gforthefullsectionofcavern.
7.2.15 Thethicknessofreinforcedconcretelinin gshallbedeter-
minedaccordin gtothecalculationandstructuralre q uirements , in
considerationoftheconstructionmethods.Thethicknessofrein-
forcedconcretelinin gwithasin g lela y erofrebarshouldnotbe
lessthan300mm.Thethicknessofreinforcedconcretelinin g
withdoublela y ersofrebarshouldnotbelessthan400mm.
Stren g thg radeofconcreteshouldnotbelowerthanC25.
7.2.16 Thesurroundin grockp ressureshallbeanal y zedanddeter-
minedbasedonthefactorsincludin gtheconditionsofsurroundin g
rocks , buriedde p thofcavern, thecrosssectionsha p eandsizeofcav-
ern, constructionmethodsandsu pp ortin gconditions , etc.accord-
in gtotheactualconditions , thefollowin gp rinci p les :

1 Forthinla y ersandloosesurroundin grocks , thep ressure
ma ybecalculatedb ytheFormula( 7.2.16 1)andFormula( 7.2.16
2)andbeu p datedaccordin gtotheactualconditions :
Vertical q vk= ( 0.2-0.3) γ RB ( 7.2.16 1)
Horizontal q hk= ( 0.05-0.10) γ RH ( 7.2.16 2)
Where:
q vk=thecharacteristicvalueofverticaluniformp ressureof
surroundin grocks , kN /m ;
2
q hk=thecharacteristicvalueofhorizontaluniformp ressure
ofsurroundin grocks , kN /m ;
2
γ R=unitwei g htofrockmass , kN /m ;
3
B=excavationwidthofthecavern,m;
H=excavationhei g htofthecavern,m.
2 Whensurroundin grocksareblock yorofmedium-to-

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