• 한국건축시공학회지
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• 제2권3호
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• pp.123-130
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• 2002

Recently, it is being studied on the high strength concrete in many laboratories and being applied to the construction field actually. But non-destruction testing equation that to be proposed about normal strength concrete in Japan has been using because the systematic study results for the estimation of compressive strength of high strength concrete do nit exist. So it is essential to suggest the non-destruction testing equation for the estimation of compressive strength of high strength concrete. This is an experimental study to analyze and investigate the non-destruction testing equation for the estimation of compressive strength of high strength concrete. The results are as follows; The relation between rebound number, pulse velocity and compressive strength of high strength concrete have lower coefficient than combined method of rebound number and pulse velocity. Also new non-destructive testing equation for the estimation on the compressive strength of high strength concrete was suggested in this study, and it is considered that these equations have possibility to be applied in domestic construction field.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.133-136
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• 2005

Compressive strength of recycled aggregate concrete was tested by the core and by the non-destructive testing. A prediction model of compressive strength considering the replacement level of recycled aggregate was suggested by multi-regression analysis and was compared with test results. Also, Test results showed that the ratio of compressive strength by core and non-destructive testing to actual was somewhat affected by the replacement level of recycled aggregate.

• 비파괴검사학회지
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• 제12권1호
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• pp.35-39
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• 1992

The purpose of this report is to obtain a practical expression for estimating the compressive strength of concrete using the non-destructive method of testing combining rebound number and ultrasonic pulse velocity at the construction sites for obtaining highest accuracy in predicting the compressive strength.

• 한국건축시공학회지
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• 제4권4호
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• pp.63-70
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• 2004

The objective of this study is to evaluate the compressive strength of recycled aggregate concrete by the non-destructive testing. Main experimental variables were the replacement level of recycled aggregate and blast-furnace slag, which were divided into two series according to recycled aggregate maximum size. Test results showed that a recycled aggregate had a significant influence on the non-destructive testing results, such as rebound number, Ultrasonic pulse velocity, and frequency. A prediction model of compressive strength considering the replacement level of recycled aggregate was suggested by multi-regression analysis and was compared with test results.

• 농업과학연구
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• 제35권1호
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• pp.19-24
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• 2008

A new compressive strength test specimen for linerboard and medium was developed, and tested for its agreement with conventional testing methods such as RCT and STFI. The new specimen enables compressive testing under the changing humidity and temperature. Experimental results showed that the new specimen gave equivalent compressive strengths as the other conventional methods at a constant temperature and humidity. We'll apply the methods under the cyclic humidity and temperature conditions.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.973-978
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• 2002

This study was performed to verify the effect of various testing conditions affecting measured compressive strength of concrete core and to compute the correction coefficients for it. Conditions of specimens affecting test results include size(diameter), height-diameter ratio, humidity of specimen, amount and arrangement of bar, core direction from structure and method of end preparation. In testing core strength of concrete, special cares should be taken on various testing conditions whose effects have been latent in conventional concrete.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.965-968
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• 2008

현재 국내현장에서 공사기간 중 구조물의 압축강도를 확인하는 방법으로는 KS F 2403에 의한 시험용 공시체의 압축강도를 구조체 콘크리트의 압축강도로 정하고 있으며, 이 규정의 내용에는 시험용 공시체의 양생방법으로 표준수중양생(20$\pm$2$^{\circ}$C)을 하도록 규정되어 있다. 그러나 현장 타설된 콘크리트의 경우 일반 대기환경에 노출되어 사계절 온도변화의 환경하에서 양생되고 있어 실 구조물의 콘크리트 압축강도와는 큰 차이를 나타내게 된다. 따라서 본 논문에서는 현재 KS에 규정되어 있는 압축강도용 시험체의 양생방법과 현장에서 구조체의 강도 및 거푸집 탈형시기 판정 등의 품질관리를 위해 사용하는 기중양생, 봉함양생, 구조체의 코어강도, 그리고 본 연구에서 제안하는 구조체의 내부환경 조건을 양생조건으로 적용한 양생방법을 적용하여 고강도 콘크리트의 강도발현특성을 파악하여 구조체 콘크리트의 강도에 가장 근접하는 공시체 양생방법을 제안하고자 한다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 추계 학술논문 발표대회
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• pp.77-78
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• 2011

This paper presents a basic study which is to develop concrete cylinder moulds for a proficiency testing compressive strength of concrete among laboratories accredited Korea Laboratory Accreditation Scheme(KOLAS). The concrete cylinder moulds sufficiently have homogeneity for a proficiency testing which is a means of assessing the ability of laboratories to competently perform specific test and measurements. The concrete compressive strength specimens placed different consolidation methods were analyzed by a statistic technique. The methods of consolidation are rodding, and internal or external vibration.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1992년도 봄 학술발표회 논문집
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• pp.114-119
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• 1992

The main disadvantages of destructive testing methods are the delay in obtaining test results, the relatively high cost of testing, and the lack of reproducibility in the test results. As a result, nondestructive testing methods are generally used. There are three objectives in this paper. The first is to determine the equations of the compressive strength of concrete estimated by Schmidt hammer technique, ultrasonic pulse velocity method and combined method respectively in laboratory. The second is to determine the correction factors according to the concrete age which affects most in evaluating the compressive strength of in-situ concrete. The third is to examine the applicability of the equations to evaluation of the compressive strength of in-situ concrete structures.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1990년도 봄 학술발표회 논문집
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• pp.20-23
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• 1990

In order to evaluate the difference of testing results in the standards on the compressive strength of various countries, we have compared the testing results of the compressive and flexural strength, one of the most important properties of cement, obtained on the various standards(KS, JIS, BS, ASTM) and the statistical method was used to evaluate the results.