ABSTRACT
Sub.. basesforflags Thedesignofsub-basesisdescribedingreaterdetailinSection1.1.Flagsmaybe laidonaconcretesub-baseoragranularsub-base.Sinceflagsarenot recommendedforroadwaysorotherareaswhichhavetotakevehicles,alighter sub-basethanthatusedforroadwaysisacceptable.Concretesub-basesshouldbe ST5(C25P)concretewith20mmaggregateatleastlOOmmthick,laidonatleast lOOmofwell-rammedhardcore.Granularsub-basesareconstructedasdescribed inSection1.1.AllfaDsfordrainageshouldbeconstructedinthesub-strateand followedinthesub-base,asattemptstomakeupdrainagefallsinthebeddingand finishwillcauseunevensettlementandirregularitiesinthefinishedsurface.
