• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.521-526
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• 2001

Box-culvert is very important structure used almost every road construction. However this is treated very simple structure in design and construction. So many crack such as nonstructural crack has been occurred. This crack is very harmful on durability of concrete. In this study, thermal crack, one of the nonstructural crack, of box-culvert controled by using rapid-strength belite cement concrete. In this process, not only heat of hydration and thermal stress but also material mechanics properties and characteristics of durability were tested. and same model box-culvert using OPC concrete is constructed in same condition for comparison.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.111-118
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• 2006

The elastic buckling strength of a corrugated culvert made of orthotropic material such as FRP was evaluated. The height and length of a corrugated wave and the thickness of the culvert were considered as factors affecting the buckling strength of the culvert. And also, the ratio of the longitudinal stiffness and transverse stiffness was considered as the parameter affecting on the buckling strength of the used orthotropic material. Buckling strengths of various corrugated culvert models with different shapes and stiffness ratio were evaluated by FE analyses and a formula to estimate the elastic buckling strength was suggested from the regression with FE analysis results. Analysis results show that a corrugated culvert has superior buckling strength to a general flat pipe and the suggested formula estimates accurate buckling strength of the corrugated culverts made of orthotropic material.

• 한국수자원학회논문집
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• 제36권3호
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• pp.481-494
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• 2003

암거흐름은 지형 및 수리조건에 따라 복잡하고, 다양한 흐름특성을 나타내고 있으며, 이로인해 암거설계는 주로 모노그래프를 이용한 설계방식을 채택하고 있는 실정이다. 이는 개수로 암거의 경우 입구부에서의 수심을 산정하여야 하는 어려움과 복잡한 흐름특성 때문인 것으로 사료된다. 본 연구에서는 사각형 암거 입구부에서의 수심을 베르누이 방정식을 이용하여 결정하였으며, 이를 적용하여 여러 가지 형태의 흐름특성에 따른 암거 설계기준식을 개발하였다. 또한 설계항목을 암거경사${\cdot}$유량${\cdot}$폭${\cdot}$높이로 구분하여 각각의 경우에 대하여 양해법 산정식을 개발하였다.

• Advances in concrete construction
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• 제15권6호
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• pp.377-389
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• 2023

In this study, an improved modular arch system with the lower arch space composed of a precast arch block and an outrigger was proposed as an underground culvert, and its applicability and structural behaviors were confirmed. This modular arch culvert structure with vertical walls was designed using precast blocks and by adjusting the placement spacing of concrete blocks to the upper part form an arch shape and the lower part form a vertical wall shape, based on previously researched modular arch systems. Owing to the vertical wall of the proposed modular arch system, it is possible to secure a load-carrying capacity and an arch space that can sufficiently resist the earth pressure generated from the backfill soil and loading on the arch system. To verify the structural characteristics, and applicability of the proposed modular precast arch culvert structure, a full-scale modular culvert specimen was fabricated, and a loading test was conducted. By examining its construction process and loading test results, the applicability and constructability of the proposed structure were analyzed along with its structural characteristics. In addition, its the structural predictability and safety for the applicability were evaluated by comparing the construction process and loading test results with the FE analysis results.

• 한국터널지하공간학회 논문집
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• 제12권2호
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• pp.193-200
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• 2010

암거구조물의 특성상 암거 표준도가 제정되어 실무에 활용되고 있다. 그러나 이는 암거구조물의 설계 및 시공성을 향상시킬 수 있으나, 다양한 현장조건에 부합하는 단면형상의 선정에 제약조건으로 작용하게 된다. 이러한 문제점을 해결하기 위하여 프리캐스트 세그먼트 조립을 통하여 다양한 형상의 암거구조물 시공이 가능한 현장 대응형 암거구조물 설계 및 시공기술을 개발하였다. 조립식 수로암거구조물의 구조적 특성상 프리캐스트 세그먼트의 연결부가 고정 또는 내부힌지 거동 여부에 따라 부재의 두께, 철근량 등이 변화하게 되며, 이는 시공성 및 경제성에 큰 영향을 미치게 된다. 따라서 본 연구에서는 세그먼트 연결부의 합리적인 모델링 기법 제시를 위하여 현장실험 및 수치해석을 수행하였다. 현장실험 및 수치 해석 분석 결과, 몰타르 충진식 슬라브를 이용한 슬라브, 벽체, 기초판 프리캐스트 세그먼트는 연결시공을 통하여 조립식 수로암거구조물은 일체화된 구조물로 거동하는 것으로 나타났다.

• 한국지반공학회논문집
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• 제27권3호
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• pp.55-61
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• 2011

일반적으로 하천제방 배수통문은 다양한 원인에 의하여 붕괴가 발생하며, 특히 연약지반 상에 말뚝기초를 이용하여 설치된 경우 1) 주변 지반(외부토체)/말뚝기초 처리된 암거 상단(내부토체)의 상대적 침하 차에 의한 배수통문 암거 측벽부의 다짐도 약화, 2) 하이드로릭 플랙처링에 의한 홍수 시 침투수압의 지속적 반복에 의한 측벽부 교란 등에 의해 붕괴가 발생한다. 특히 측벽부는 시공여건상 다짐장비의 접근이 어려운 다짐 취약부이고, 이질재료에 의한 마찰력 감소로 전단저항력이 일반 흙의 전단강도에 비해 1/3 이상 감소하여 발현된다. 이에 본 연구에서는 주변 지반에 인위적인 변형을 발생시키는 방법으로 침하를 모사한 실내 모형실험을 통하여 연약지반 상 말뚝 기초된 배수통문 암거의 상대적 침하에 따른 외부토체/내부토체 발현 메카니즘과 저판확폭에 따른 배수통문 암거 측벽부 다짐도 향상 효과를 비교 분석함으로써 배수통문 저판 확폭을 통한 주변지반 공동 확장 억제기법을 제시하였다.

• Geomechanics and Engineering
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• 제11권5호
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• pp.625-638
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• 2016

This paper presents field study and numerical modeling results for a single-cell low-fill concrete box culvert under a flexible pavement subjected to traffic loading. The culvert in the field test was instrumented with displacement transducers to capture the deformations resulting from different combinations of static and traffic loads. A low-boy truck with a known axle configuration and loads was used to apply seven static load combinations and traffic loads at different speeds. Deflections under the culvert roof were measured during loading. Soil and pavement samples were obtained by drilling operation on the test site. The properties of the soil and pavement layers were determined in the laboratory. A 3-D numerical model of the culvert was developed using a finite difference program FLAC3D. Linear elastic models were used for the pavement layers and soil. The numerical results with the material properties determined in the laboratory were compared with the field test results. The observed deflections in the field test were generally smaller under moving loads than static loads. The maximum deflections measured during the static and traffic loads were 0.6 mm and 0.41 mm respectively. The deflections computed by the numerical method were in good agreement with those observed in the field test. The deflection profiles obtained from the field test and the numerical simulation suggest that the traffic load acted more like a concentrated load distributed over a limited area on the culvert. Elastic models for culverts, pavement layers, and surrounding soil are appropriate for numerical modeling of box culverts under loading for load rating purposes.

• 농업과학연구
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• 제47권2호
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• pp.263-273
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• 2020

With the change of the agricultural environment (increased rice production, decreased rice consumption, and rice production policies), converting paddy fields into upland fields is an increasing trend. In terms of conversion into upland fields, subsurface drainage is one of the most important factors for good field crop growth. This study evaluates the performance of a subsurface drainage culvert system in paddy fields and reclaimed lands. The obtained results are briefly summarized as follows: 1) After a comparative evaluation of several subsurface drainage culvert systems, including excavated subsurface drainage and non-excavated subsurface drainage types, type 3 (non-excavated, perforated drain pipe 50 mm, filter mat B50 cm, subsoiling 70 cm and culvert spacing 5 m) shows relatively high values among four types in terms of effectiveness (subsurface discharge capability) and economic efficiency (construction cost). 2) Type 3 has proven that it is suitable for design standards of discharge capacity through field tests performed in paddy fields (three sites: Gong-geom, Gae-san, Juk-san) and reclaimed lands (two sites: Gum-ho, Mi-am). 3) In the experiment of Sesamum indicum growth according to the existence of a drainage system, Sesamum indicum growth with a subsurface drainage culvert system had good value in terms of plant shoot and root length, shoot fresh and dry weight, and root fresh and dry weight).

• 한국수자원학회논문집
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• 제43권3호
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• pp.275-282
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• 2010

암거의 규격 설계는 상류부의 수위를 과다하게 상승시키지 않는 상태에서 안전하게 계획홍수량을 하류로 소통시킬 수 있도록 최적의 단면을 결정하는 것이다. 현재 국내 암거 설계는 한국도로공사(1991)에서 발표한 "도로배수계획"을 이용하고 있는데, 이는 주로 미국도로성(FHWA)에서 발표한 설계기법을 따른 것이다. 이 기법은 계산 도표를 이용하여 설계하는 방법으로 주관적인 오차가 생길 수 있으며 전산해석에 있어서도 큰 장애요인이 될 수 있다. 본 연구에서는 기존 연구에서 기술된 암거 설계법을 전반적으로 재검토하여 일부 수식 전개 과정에서 발생한 오류를 수정하고, 암거의 규격 산정 시 암거의 형상을 미리 결정하여 암거 프로그램 개발 시 효율적일 것으로 판단되는 새로운 방법을 개발하였다. 특히 원형 암거의 수리해석 시 한계수심과 한계조건 속도수두의 해를 미국도로성에서는 계산도표를 이용하여 구하는 기법을 제시한 반면에 본 연구에서는 양해적 산정식으로 구하는 기법을 개발하였다.

• 한국도로학회논문집
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• 제15권5호
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• pp.47-55
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• 2013

PURPOSES : The purpose of this study is to investigate the optimal joint positions which can minimize distresses of concrete pavement containing box culvert with horizontally skewed angles. METHODS : The concrete pavement containing the box culvert with different skewed angles and soil cover depths was modeled by 3 dimensional finite element method. The contact boundary condition was used between concrete and soil structures in addition to the nonlinear material property of soil in the finite element model. A dynamic analysis was performed by applying the self weight of pavement, negative temperature gradient of slab, and moving vehicle load simultaneously. RESULTS : In case of zero skewed angle ($0^{\circ}$), the maximum tensile stress of slab was the lowest when the joint was positioned directly over side of box culvert. In case there was a skewed angle, the maximum tensile stress of slab was the lowest when the joint passed the intersection between side of the box culvert and longitudinal centerline of slab. The magnitude of the maximum tensile stress converged to a constant value regardless the joint position from 3m of soil cover depth at all of the horizontally skewed angles. CONCLUSIONS : More reasonable and accurate design of the concrete pavement containing the box culvert can be possible based on the research results.