기계적 교정에 의한 강재의 소재특성 변화에 관한 연구 = Variation Analysis of Material Characteristics of Steel through Mechanical Calibration

다국어 초록 (Multilingual Abstract)

Steel elements exhibit varying characteristics during site installation after shop manufacturing. There may be a mix-up owing to unclear management methods for transport, and deformation might occur during field installation. Moreover, the technical basis for evaluating repair methods is narrow. In this study, variations in material properties after performing mechanical calibration were determined for widely used steel types, such as SS400 and SM490, in which thicknesses of 30 mm and less are frequently used on sites. The test results showed that the mechanical calibration in unheated and thermal heating cases increased the yield strength and tensile strength of steel, and the Korea Standard value was satisfied. A yield ratio of approximately 85% or less was obtained, indicating sufficient toughness. In addition, variations owing to thermal heating did not occur when temperatures below 650 °C were applied.

국문 초록 (Abstract)

강구조는 공장제작 후 현장설치 하는 제작 특성으로 운반 및 현장설치 과정에서 발생하는 변형 등에 대한 관리방안이 불명확하여현장감독자 및 제작자 간에 약간의 불협화음이 발생하는 경우가 있다. 또한 보수방법에 대한 기술적 판단근거가 적은 것이사실이다. 이에 본 연구에서는 현장에서 많이 사용되는 30 mm 이하의 판재(30 mm, 12 mm)와 가장 일반적으로 사용되는강종(SS400, SM490)에 대해 교정 후 소재특성의 변화 등을 시험으로 확인하였다. 시험결과 기계적 교정(비가열교정과 가열교정) 은 강재의 항복강도와 인장강도를 상승시키나 KS 규정 값은 만족하며, 항복비도 85% 이하를 나타내어 충분한 인성을 확보할수 있을 것으로 판단된다. 또한 650 ℃ 이하의 온도로 관리하면, 가열교정에 의한 조직변화는 발생하지 않을 것으로 판단된다.

참고문헌 (Reference)

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