3D CREEP RESPONSE OF NUCLEAR CONCRETE

摘要

Concrete creep research has focused primarily onuniaxial response. However, in nuclear structures, there isa 3D state of stress that complicates the response, despitethe isotropy of the concrete. Significant creep strains maybe induced in directions transverse to each principle stressdue to Poisson’s effect. Past research is unclear regardingthe viscoeleastic (VE)/ viscoplastic (VP) properties ofconcrete outside of uniaxial response. For example, it hasbeen reported in separate studies that concrete creepPoisson’s ratio is an increasing, decreasing and constantfunction with time. Given the geometry and structuraldetailing in US containment structures, accurate modelingof structural-scale creep and creep-cracking will be aidedby a full 3D treatment of both the material and structure.The quantification of the 3D creep response of concretewas achieved using a novel, confined compressionexperiment that allows direct determination of the fullstress and infinitesimal strain tensors in a single test.