Summary of Japan Society for Non-Destructive Inspection Standard NDIS 3439 “Method of sampling and testing for compressive strength of small size drilled cores of concrete”

Abstract

A recent trend is the dense arrangement of rebar in concrete structures. This makes it difficult to collect cores with a diameter larger than three times the maximum size of the coarse aggregate from actual structures. For this reason, strength estimation of structural concrete has been performed using cores with diameters less than three times the maximum size of the coarse aggregate, which are not covered by JIS A 1107. In November 2022, the Japan Society for Non-Destructive Inspection established the standard NDIS 3439, “Method of sampling and testing for compressive strength of small size drilled cores of concrete” as a method for estimating the strength of structural concrete. This paper introduces the content of the studies conducted up to the establishment of the standard and gives an overview of the standard.