• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.385-386
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• 2009

The temperature crack of concrete structure is caused by the phenomenon which the concrete volume is restricted in the inside or outside part due th the temperature variations induced by the hydration heat of cement. And mass concrete structures are weak in temperature crack. This study performed the hydration heat analysis of Seongdeok dam to analyze the hydration heat according to different interval of placement.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.634-639
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• 2008

일부 콘크리트댐들의 경우 이상홍수 발생시 상 하류부 수위차가 크지 않은 상태로 월류가 발생하는 특징이 있으며, 치수능력 증대사업을 수행하여 안전성을 확보하기에는 지리적, 경제적인 문제로 어려움이 많아 현실적인 대책 수립이 어려우므로 월류가 발생한 상태에서도 안전성이 확보될 수 있는가에 대한 검토가 필요하다. 한국시설안전공단(2007)에서는 기존 댐의 수문학적 안전성 평가를 필댐과 콘크리트댐으로 구분 적용할 필요성과, 콘크리트댐의 경우 상태에 따라 일부 월류를 허용할 수 있는 방안에 대한 연구를 수행하였으며, 본 연구는 콘크리트 댐의 구조적 안전성 검토의 평가방법으로 수행하게 되었다.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.517-520
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• 2008

Gravity dam use self weight to stand external force like hydraulic pressure. In general, gravity dam concrete is divided into internal and external concrete. Seongdeok dam is gravity dam which is being constructed in Cheongsong-gun, Gyeonsangbuk-do. And upstream cofferdam was constructed to examine the temperature crack due to hydration heat and to decide the height of placement. In this study, we examined the mix design of internal/external concrete and physical properties(compressive strength, adiabatic temperature rise). And we also performed laboratory tests to verify exothermic properties. Lastly, we measured the hydration heat and thermal stress of upstream cofferdam.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.412-425
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• 2012

Concrete Soil Erosion Control Dam, which blocks flow of debris flow in torrential stream, are reported to lose expected functions due to structural failure and collapses, caused by poor construction, material deterioration and external impacts. In this paper, an integrity assessment technique for debris barriers was proposed, which allows preliminary detection of problems inherent in debris barriers. The proposed integrity assessment technique is a non-destructive method based on SASW method, one of surface-wave tests. In this paper, a practical procedure and analysis guidelines in applying the SASW technique to debris barrier was proposed and its validity was verified using five decrepit debris barriers older than 20-year old. As a result, the SASW method was validated for the reliable grade evaluation method for concrete soil erosion control dam, and the resulting grades turned out to agree with the results determined by Sabang Associations.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1467-1471
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• 2008

한탄강홍수조절댐의 형식은 기본설계(TK)시 지형 및 지질조건, 재료원 조건, 댐 안정성, 여수로설치조건, 친환경조건, 경제성 등을 종합적으로 고려하여 콘크리트중력심댐으로 결정하였으며, 콘크리트 중력심댐 축조를 위한 공법으로 재래식 타설공법과, Layer 타설공법을 가설비 규모, 시공성, 공기 등을 비교 검토하여 Layer 타설공법(R.C.D)을 채택하였다. Layer 타설공법은 일정 물량에 이상에 대해서는 일반 콘크리트 블록식 타설공법과 비교하여 경제성과 시공성 등이 양호하다고 할 수 있다. 본 연구에서는 현재 사업 진행중인 한탄강홍수조절댐을 통한 R.C.D공법과 일반 블록식 콘크리트 타설 방법을 비교 분석하고자 한다.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.4
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• pp.43-50
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• 2004

A large concrete dam, of which construction work had not been continued for more than 20 years because of social problem, was investigated with emphasis on its seismic performance. Mechanical properties of the concrete dam material were estimated by performing uniaxial compression tests for obtained the samples from dam body. Borehole image Processing System (BIPS) was used to investigate the susceptible faults developed in the interface between old an new concretes. Using the results of several laboratory and field tests earthquake response analysis for the dam were done, The results of such investigation show that its physical and mechanical conditions are in a good condition, and the results earthquake response analysis imply that the dam, even it consists of two different concretes, show good seismic performance.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3C
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• pp.209-218
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• 2006

In this study, stress and deformation of CFRD during its construction and impounding were analyzed and compared with its monitoring results. Moreover, deformation characteristics of CFRD after impounding were evaluated based on the settlement monitoring records of total 23 domestic and foreign CFRDs during construction and impounding. The investigation on the behavior of CFRD indicated that the influence of impounding on its stability was minimal although slight increases in vertical and horizontal stresses and strains were observed. Also, one method was proposed to predict a crest settlement from multi-layer settlements by applying the best fit method. It is expected that the results of this study would provide practical information for the design, construction, and management of CFRD.

• Journal of the Korea Concrete Institute
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• v.16 no.6 s.84
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• pp.841-850
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• 2004

The modeling of uplift pressure within dam, on the foundation on which it was constructed, and on the interface between the dam and foundation is a critical aspect in the analysis of concrete gravity dams, i.e. crack stability in concrete dam can correctly be predicted when uplift pressures are accurately modelled. Current models consider a uniform uplift distribution, but recent experimental results show that it varies along the crack faces and the procedures for modeling uplift pressures are well established for the traditional hand-calculation methods, but this is not the case for finite element (FE) analysis. In large structures, such as dams, because of smaller size of the fracture process zone with respect to the structure size, limited errors should occur under the assumptions of linear elastic fracture mechanics (LEFM). In this paper, the fracture behaviour of concrete gravity dams mainly subjected to uplift Pressure at the crack face was studied. Triangular type, trapezoidal type and parabolic type distribution of the uplift pressure including uniform type were considered in case of evaluating stress intensity factor by surface integral method. The effects of body forces, overtopping pressures are also considered and a parametric study of gravity dams under the assumption of LEFM is performed.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.1
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• pp.9-18
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• 2023

The purpose of this paper is to review the appropriateness of the application method for the value of the damping ratio suggested in the current design standards and evaluation guidelines when evaluating the seismic performance of concrete dams and to suggest improvements. As a result of the study, for the magnitude of the damping ratio in the dynamic elastic analysis, it is necessary to refer to the case of a similar dam in which the magnitude of the earthquake load is similar and the reproducibility of the damping ratio has been verified. Considering this, it is necessary to apply a low damping ratio and consider adding hysteresis damping in case of nonlinear behavior. In addition, since the concrete dam body located on the rock has insignificant radiation attenuation effect, it is not reasonable to increase the damping ratio of the concrete dam body to reflect the radiation damping. Therefore, in order to evaluate the realistic seismic performance of concrete dams, it is necessary to revise the damping ratio-related contents contained in the current dam design standards and evaluation guidelines.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.161-164
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• 2008

It is played an important part in dam safety that KWATER is taken the responsibility of design, construction and maintenance about dam. It is considered that safety inspection of accumulated technology and knowledge of new evaluation method have developed. Thus this study is that instrumentation data is analyzed continually and dam's safety is evaluated about behavior property, in Chungju concrete dam. New evaluation method is that instrumentation data is analyzed reliability. It is suggested that suitability of management period and maintenance of instrument in dams.