• 주택과사람들
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• no.47 s.64
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• pp.83-90
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• 1995

건설기술관리법 제24조의 2 및 동법시행령 제47조의 3의 규정에 의한 품질시험 실시 대상 건설자재인 레디믹스트콘크리트에 대하여 당해건설공사의 품질을 철저하게 확보함과 동시에 적기공급을 도모하기 위해서 시공자가 현장배치플랜트를 설치하여 직접 생산${\cdot}$사용하는 경우 당해시공자 및 레디믹스트콘크리트 전문제조업자가 준수하여야 할 지침을 다음과 같이 고시합니다.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.973-976
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• 2008

Recently, it is increasingly reported that the deterioration of concrete structure under marine environments is due to diffusion and penetration of chloride ions. It is very important to estimate the diffusion coefficient of chloride ion in concrete. Estimation methods of chloride diffusivity by concentration difference is time-consuming. Therefore, chloride diffusivity of concrete is mainly conducted by electrically accelerated method, which is accelerating the movement of chloride ion by potential difference. However, there has not been any proper method for field quality control to closely determine the diffusion coefficient of chloride ion through accelerated tests using potential difference. In this paper, the various test methods for determination of chloride diffusion coefficient in concrete were investigated through comparison accelerated tests. From the results of estimated diffusion coefficient of chloride ion, relationship between the ponding test and acceleration test was examined.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4A
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• pp.603-609
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• 2008

The recycled aggregates which were produced from the waste concretes have the disadvantages of inferior properties for natural aggregate. Therefore, in order to reuse the recycled aggregate it must be solved to improve the quality of recycled aggregate. In this study, the quality of recycled aggregate was improved by the surface treatment method using the colloidal silica solution. And, in order to examine the possibility of reusing the surface coated recycled aggregate in constructing concrete structures, we studied the mechanical properties and durability of the concrete using the surface coated recycled aggregates and the other concrete.

• Resources Recycling
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• v.18 no.3
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• pp.27-35
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• 2009

To solve resource exhaustion and waste management problems caused by mass consumption, there are many efforts to change from resource consumption system to recycling system. Specially, interests about management of construction waste have increased, but efficient recycling system of waste concrete is not established yet. In this study, high quality recycled aggregate processing circuit was developed to recycle waste concrete. From the waste concrete which is a hydrated compound with coarse aggregate, fine aggregate, and cement material, high quality recycled coarse aggregate for concrete making was produced by autogenous milling and heat pretreatment method. After then, refinement process was performed to separate fine aggregate and cement material from waste concrete fines by sink float separation and hindered-settling separation. As a result, high quality recycled aggregate was produced from waste concrete by developed processing circuit.

• Magazine of the Korea Concrete Institute
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• v.3 no.4
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• pp.35-37
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• 1991

• Magazine of the Korea Concrete Institute
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• v.3 no.1
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• pp.33-41
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• 1991

• Magazine of the Korea Concrete Institute
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• v.13 no.3
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• pp.55-60
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• 2001

• Magazine of the Korea Concrete Institute
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• v.9 no.2
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• pp.23-29
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• 1997

• 레미콘
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• no.12 s.6
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• pp.24-30
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• 1985

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.4
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• pp.320-327
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• 2015

This study implicates a quality evaluation technique for lining concrete using the ultra-sonic technique and proposed a classification for quality evaluation. From the comparison of test results, an improved result comparable to the results by destructive test can be obtained by using averaged transmission velocity of velocities obtained at pure space and central space between two sensors of ultrasonic tester. It is also shown that strength evaluation by ultra-sonic method is not reliable and an evaluation according to the transmission velocities can be improved method for the strength evaluation of concrete.