• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 봄 학술발표회 논문집
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• pp.241-246
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• 1996

A new solution for the dynamic analysis of as asphalt concrete pavements under moving loads has been developed. The asphalt concrete pavement can be modeled in elastic or viscoelastic medium of multi-layered structure. The subgrade can be modeled as either a rigid base or a semi-infinite halfspace. The loads may be constant or arbitrary circular loads into one direction. The method utilizes the Complex Response Method of transient analysis with a continuum solution in the horizontal direction and a finite-element solution in the vertical direction. This proposed method incorporates such important factors as wave propagation, inertia and damping effects of the medium as well as frequency-dependent asphalt concrete properties. The proposed method has been validted with the full-scale field truck test, which was conducted on instrumented asphalt concrete section on a test track at PACCAR Technical Center in Mount Vernon, Washington. Comparison with field strain data from full-scale pavement tests has shown excellent agreement. Theoretical results have shown that the effect of vehicle speed is significant and that it is in part due to the frequency-dependent

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.699-702
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• 2005

This study evaluates the properties of porous concrete for pavement according to content of silica fume and steel fiber. The results of the test indicate that in every condition, the void ratio and the coefficient of water permeability of porous concrete for pavement satisfy both the domestic standards and proposition values. Among the properties of strength, the compressive strength satisfies the standards in the specification of KNHC as for every factor of mixture but in the case of the flexural strength, more than $0.6vol.\%$ of steel fiber satisfied the JCI proposition values. The case when silica fume and steel fiber are used simultaneously presents the strongest durability and Noise Reduction Coefficient is 0.48 to prove that it possesses almost $50\%$ sound absorption.

• 한국도로학회논문집
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• 제15권3호
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• pp.45-52
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• 2013

PURPOSES : This study is to construct the regression models of drainage asphalt concrete specimens and to provide the appropriate coefficients of hydraulic conductivity prediction models. METHODS: In terms of easy calculation of the hydraulic conductivity from porosity of asphalt concrete pavement, the estimation model of hydraulic conductivity was proposed using regression analysis. 10 specimens of drainage asphalt concrete pavement were made for measurement of the hydraulic conductivity. Hydraulic conductivity model proposed in this study was calculated by empirical model based on porosity and the grain size. In this study, it shows the compared results from permeability measured test and empirical equation, and the suitability of proposed model, using regression analysis. RESULTS: As the result of the regression analysis, the hydraulic conductivity calculated from the proposal model was similar to that resulted from permeability measured test. Also result of RMSE (Root Mean Square Error) analysis, a proposed regression model is resulted in more accurate model. CONCLUSIONS: The proposed model can be used in case of estimating the hydraulic conductivity at drainage asphalt concrete pavements in fields.

• 한국도로학회논문집
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• 제16권3호
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• pp.51-57
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• 2014

PURPOSES : This study is to suggest tunnel length to spray curing compound, based on the field tests. METHODS : At first field test, length from the entrance of tunnel to wet wall was checked by visual survey. The second and third test, various sensors were installed in concrete or in tunnel, such as RH sensor, temperature sensor, portable weather station and etc.. And also, test for bleeding and retaining water of concrete were conducted to evaluate environmental effect on concrete pavement. RESULTS : The result of the field experiment for tunnel length to spray curing compound indicates that length changes depending on tunnel length, season, and location. Environmental condition of a short tunnel was not much different between location near entrance and at center of tunnel. However, in case of a medium and long tunnel, effect of outside environmental condition decreased, when location moved into tunnel center of it. CONCLUSIONS : From the testing results, it can be proposed that optimum tunnel length to spray curing compound is 60m for a medium and long tunnel, and whole length for a short tunnel.

• 한국도로학회논문집
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• 제13권1호
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• pp.79-86
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• 2011

최근 화석자원의 고갈과 대기오염의 피해를 저감하기 위해 자전거의 이용을 적극적으로 장려하고 있으며 이를 위해 자전거도로 건설이 활발히 이루어지고 있다. 하지만 현재 사용 중인 자전거도로 포장은 이용 하중에 비해 높은 성능과 시공비용을 지니고 있어 효율적인 건설을 위해 경제적인 도로포장형식이 필요하다. 롤러 전압 콘크리트 포장은 시멘트 경화 반응과 다짐으로 인한 골재 맞물림에 따른 높은 구조적 성능을 확보할 수 있다. 또한 시공이 간단하고 건설비가 적어서 자전거도로에 적용하기 위한 우수한 조건을 갖추고 있다. 그러나 롤러 전압 콘크리트 포장의 불량한 표면 미관과 제설제 피해에 대한 취약성은 자전거도로 건설에서 문제로 작용하고 있다. 따라서 이러한 단점을 극복하기 위해 표면 미관의 개선과 환경하중에 대한 피해를 저감 할 수 있을 것으로 예상되는 코팅공법을 이용하였으며 이에 대한 효과를 검증하기 위해 롤러 전압 콘크리트 포장의 코팅에 따른 성능을 검토하였다.

• 대한토목학회논문집
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• 제42권4호
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• pp.537-548
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• 2022

중하중의 교통하중은 포장체에 과도한 응력과 변형을 발생시키므로 이에 대응할 수 있는 포장 단면 설계가 중요하다. 항만 배후도로와 산업도로는 일반도로에 비해 중하중 교통의 비율이 높아 포장의 조기 파손으로 인한 문제가 다수 발생되고 있다. 국외의 경우 중차량의 통행이 많은 도로의 포장설계는 복합포장을 많이 적용하고 있다. 복합포장은 기존 포장의 설계수명을 2배 이상 증대시켜 보수비용 및 사용자 비용을 절감할 수 있는 경제적 포장 형식으로 인식되고 있다. 본 연구에서는 중하중 교통의 비율이 높은 산업도로와 항만 배후도로의 포장 장기 공용성을 확보할 수 있도록 롤러전압콘크리트 기층을 활용한 복합포장의 두께 설계 방안을 제안하고자 한다. 3차원 유한요소해석을 이용하여 포장의 재료물성 변화에 따른 역학적 거동과 장기 공용성을 검토하였으며, 계절별 컨테이너 트레일러에 의해 발생되는 롤러전압콘크리트 기층의 누적피로손상도을 고려하여 사용자가 쉽게 사용할 수 있는 카탈로그 설계를 제안하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.432-437
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• 2004

In this study, Pavement Management System(PMS) was developed to overcome the unscientific pavement management limitations of the past. PMS program is economic, efficient and scientific. Also, it produces the best maintenance method through exact judgement and logical analysis of pavement condition. First of all, the logical algorithm, that is such as investigation and analysis of pavement, detailed naked eye investigation and the estimation for whole system etc., was composed on the basis of the domestic and the outside data on PMS and pavement condition data of Seoul metropolitan. And then it was verified that this algorithm is suitable through the research examples of PMS data and the results of detailed naked eye investigation. Also, Geographic Information System(GIS) was integrated on PMS program. Therefore, PMS program was developed so as to use easily on the basis of the logical algorithm.

• 한국도로학회논문집
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• 제6권3호
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• pp.27-35
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• 2004

공용중인 공항 콘크리트 포장의 잔존수명을 추정하는 방법은 크게 과거의 누적 교통량을 고려하는 방법, 이론적 해석을 통한 역학적 방법 등 두 가지로 구분할 수 있다. 단순히 과거의 누적교통량을 이용하는 방법은 노후포장의 잔존수명을 추정하기에는 현실과 많은 차이가 있기 때문에 최근들어 많은 연구자들은 역학적 해석에 의한 방법을 많이 채택하고 있다. 역학적 방법에서 피로식은 잔존수명산출의 핵심을 이루는 것으로서 그 역할은 매우 중요하다고 할 수 있다. 본 연구는 국내 공항 콘크리트 포장의 피로식을 개발하기 위한 연구이다. 이를 위하여 재령이 10년된 공항을 선정하여 30개의 코어시료를 채취하여 피로시험을 실시하였다. 피로실험은 쪼갬인장 모드를 이용하여 수행하였으며 응력비 산정을 위한 기준 강도도 코어시료의 쪼갬인장 강도를 통해 얻었다. 본 연구에서 얻은 피로식의 상관계수값은 0.5였으며, 이 모델을 검증하기 위해 다른 공항에서 채취한 시료를 이용하여 실험을 수행하였으며 실험결과는 본 연구에서 제시된 피로식에 크게 벗어나지 않는 것을 확인하였다. 본 피로식을 기존의 외국 연구와 비교한 결과 응력비가 80%이상인 구간에서는 피로수명이 약간 큰 것으로 나타났다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.537-540
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• 2004

Recently, for industrial development period, concrete structures in domestics have been increased. They were deteriorated by attack of carbonation, freeze-thaw and corrosion etc. In hence they were demolished and reconstructed, resulted in waste concrete particles. In this paper, waste concrete particles (WCP) by product from different crushing and selecting process were used in soil cement-based pavement in the various recycling. For using WCP in soil cement-based pavement, the Qualities, physical and chemical properties, of WCP should be researched. In the first step, the specified compressive strength of mortar for two types of clay sand soil and clay soil respectively was experimented to be 15 Mpa and then optimum mixing ratio of chemical solidification agent were decided in the range of $1.5\~3.0\%$ in the replacement with cement weight content. In the second step, based on the prior experimental results, recycling possibility of WCP in soil cement-based pavement was studied. In the result of experiment the mixing ratio of WCP were 5, 10, 15 and $20\%$ in the replacement with soil weight and the compressive strength of mortar was somewhat decreased according to the increase of the mixing ratio of WCP.

• 한국농공학회논문집
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• 제64권6호
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• pp.25-34
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• 2022

Recently, as a study to air cooled slag, which is an industrial by-product, research is being proceed to use it as a material for concrete. In this study, the workability, air content, compressive strength, CO₂ emission and economic feasibility of concrete were analyzed when air cooled slag, an industrial by-product, was applied as aggregate for rural road pavement concrete. As a result of the analysis, both the slump and air contents test results of concrete using the air cooled slag aggregate satisfied the target values, and the compressive strength was increased when the air cooled slag aggregate was used compared to when the natural aggregate was applied. On the other hand, the largest amount of CO₂ emission by raw material was found in aggregate. The carbon emission of rural road pavement concrete using air cooled slag aggregate increased when the Korean LCI DB was applied compared to when natural and crushed aggregates were applied, and the emission decreased when the German LCI DB was applied. This results are due to differences in the viewpoints of industrial by-products. However, considering the recycling of waste from the environmental aspect, it is necessary to simultaneously review the CO₂ emission and recycling aspects in the future. Also, the application of air cooled slag aggregate had the effect of improving the economic efficiency of rural road pavement concrete about 18.75%.