• Title/Summary/Keyword: 기층

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Noise Reduction Characteristic of Total Quiet Pavement System (저소음 포장체의 소음저감 특성)

  • Lee, Kwan-Ho;Park, Woo-Jin
    • International Journal of Highway Engineering
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    • v.14 no.1
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    • pp.25-34
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    • 2012
  • The rapid economic development induced the massive road constructions, becoming bigger and high-speed of the vehicles. However, it brings lots of social problems, such as air pollutions, traffic noise and vibration. Special concrete block for the base course of asphalt pavement is needed to decrease traffic noise such as tire's explosive and vehicles sound, applying Helmholtz Resonators theory to asphalt pavement. If it is applied to the area where it happens considerable noise such as a junction, the street of a housing complex and a residential street, it is one of alternative methods to solve the social requirements of noise problems. This research examines couple of laboratory tests for the sound absorption effect of the concrete block and the base concrete block for quiet pavement. The specimens, which is fixed hall-size, space, depth as the condition of this research, are analysed of noise reduction effect using different noise levels of vehicles. Judging from the analysis of test results with vehicle noise volume, measurement distance, a form and size of the hall using the base concrete block, the use of special concrete base and quiet asphalt surface showed a good alternative solution for decreasing traffic noise level, from 4dB to 9dB.

An Analysis on Characteristics of Thickness of Asphalt Concrete Pavement with Computer Programs (전산해석 프로그램을 이용한 아스팔트포장 단면의 거동특성분석)

  • Lee, Gyeong-Ha;Lee, Gwang-Ho
    • International Journal of Highway Engineering
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    • v.1 no.2
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    • pp.155-168
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    • 1999
  • Asphalt pavement tends to rut in high temperature and to crack in cold temperature. The performance of asphalt pavement can be deteriorated by korean weather condition which has the four distinct seasons. In this study, the typical sections that may minimize rutting and fatigue were analyzed through the numerical model tests. The layered elastic theory , finite element method and visco elastic theory were utilized for these numerical model tests. From the various numerical model tests, it is found that an optimum design procedure was recommended. It was increasing the thickness of asphalt stabilized base with fixing the wearing course as 5cm the minimum specified thickness. The section was most beneficial in resting rutting and fatigue. From the analysis of the relative index on tensile strain and cost analysis, it was recommended that the thickness ratio of subbase and asphalt concrete is 1.0$\sim$2.5.

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Research on Practical Rubblization in PCC Pavements Equipment Development and Test Construction (원위치파쇄기층화 공법의 실용화를 위한 장비개발 및 시험시공)

  • Lee, Seung Woo;Han, Seung Hwan;Ko, Suck Bum;Kim, Ji Won
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.1D
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    • pp.81-87
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    • 2006
  • The rubblization technique is breaking the aged concrete pavement slab into rubblized concrete aggregate, and use it as an base material at its original position, then builds overlay above the rubblized base. This method has been successively used in USA due to the advantage of good constructibility, cost-effectiveness as well as the capability of preventing of reflection cracks. However, constructibility and economic performance of rubblization on typical Korean concrete pavements needed to be investigate since to typical Korean concrete pavements have thick slab, as well include lean concrete subbase course. Multi-head type breaker suitable for Korean condition was designed and developed. This multi-head type breaker was designed to rubblize old concrete to the suggested optimum rubblized-depth and rubblized-concrete-aggregate size to prevent reflection crack and maintain high bearing capacity. This machine was used for the test of rubblization of old concrete pavement on a non-use old concrete and a in-serviced road. In these two tests, engineering properties of rubblized base and constructability and cost were investigated. In both tests, the old concrete rubblized to targeted size and depth, and high-level bearing capacity was achieved. Also, superior constructability and lower cost compared with traditional reconstruction was examined.

Condition Evaluation of the Pavement Foundations Using Multi-load Level FWD Deflections (다단계 하중 FWD를 사용한 도로기초 상태평가 연구)

  • Park, Hee-Mun;Kim, Richard Y.;Park, Seong-Wan
    • Journal of the Korean Geotechnical Society
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    • v.19 no.6
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    • pp.261-271
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    • 2003
  • A condition evaluation procedure for the pavement foundations using multi-load level Falling Weight Deflectometer(FWD) deflections is presented in this paper. A dynamic finite element program incorporating a stress-dependent material model, was used to generate the synthetic deflection database. Based on this synthetic database, the relationships between surface deflections and critical responses, such as stresses and strains in base and subgrade layers, have been established. FWD deflection data, Dynamic Cone Penetrometer(UP) data, and repeated load resilient modulus testing results used in developing this procedure were collected from the Long Term Pavement Performance (LTPP) and North Carolina Department of Transportation (NCDOT) database. Research effort focused on investigation of the effect of the FWD load level on the condition evaluation procedures. The results indicate that the proposed procedure can estimate the pavement foundation conditions. It is also found that structurally adjusted Base Damage Index (BDI) and Base Curvature Index (BCI) are good indicators for the prediction of stiffness characteristics of aggregate base and subgrade respectively. A FWD test with a load of 66.7 kN or less does not improve the accuracy of this procedure. Results from the study for the nonlinear behavior of a pavement foundations indicate that the deflection ratio obtained from multi-load level deflections can predict the type and quality of the pavement foundation materials.

Rubblization of Thick Concrete Pavement (두꺼운 콘크리트포장의 원위치파쇄 기층화공법)

  • Lee Seung-Woo;Han Seung-Hwan;Ko Suck-Bum;Kim Ji-Won
    • International Journal of Highway Engineering
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    • v.8 no.3 s.29
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    • pp.105-114
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    • 2006
  • A popular alternative to extend the life of aged pavement is asphalt overlay. However, it has a very serious and inherent shortcoming in deterring a reflection crack. Although joint-rehabilitation and stress-relief techniques have been applied to deter such reflection cracks in aged pavement, the techniques had a limited success only in slowing down the progress of a reflection crack. Rubblization technique rubblizes the concrete pavement slab in situ and uses the rubblized slab as the base material. Then, pavement overlay is applied to finish off the rehabilitation of aged pavement. This rubblization technique has the advantage of solving the problem of reflection cracking completely. When rubblization technique is applied, the upper layer of aged concrete pavement is rubblized between 40mm-70mm in depth. However, the lower layer is typically rubblized more than 100mm in depth. Nevertheless, it is difficult to turn the entire concrete pavement of more than 30cm in depth into rubblized aggregate of appropriate size. Thus, a simulation experiment was carried out to find the appropriate rubblized depth, which avoids the reflection cracking and still maintains the function of subbase, by varying the depth of rubblized depth in loom increments of 0cm, 10cm, and 20cm. The result indicated the optimum rubblized depth was 10cm (Lee, 2006). Additionally, a small rubblizinge equipment was developed in order to derive the rubblization technique appropriate for thick concrete pavement. This equipment was tested out on an experimental pavement, which was constructed with the same standard and specification for the road in actual use, by varying its rubblizing head shape and energy as well as the effective area of rubblization. This experiment led to a prototype equipment for rubblization of thick concrete pavement. The prototype was put into use on a highway, undergoing a test construction and monitoring afterwards. This entire process was necessary for the validation of the proposed rubblization technique.

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Development of the Structural Condition Evaluation Technique for Asphalt Pavements Using Falling Weight Deflectometer Deflections (Falling Weight Deflectometer 처짐값을 이욤한 아스팔트 포장체의 구조적 상태 평가기법 개발)

  • Son, Jong-Chul;Rhee, Suk-Keun;An, Deok-Soon;Park, Hee-Mun
    • International Journal of Highway Engineering
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    • v.8 no.4 s.30
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    • pp.115-124
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    • 2006
  • The objectives of this paper are to develop the structural condition evaluation technique using Falling Weight Deflectometer deflections and propose the structural condition criteria for asphalt pavements. To figure out correlation between surface deflections and critical pavement responses, the synthetic database has been established using the finite element pavement structural analysis program. A regression approach was adopted to develop the pavement response model that can be used to compute the stresses and strains within pavement structure using the FWD deflections. Based on the pavement response model, the procedure for assessing the structural condition of pavement layers was proposed in this study. To validate the condition evaluation procedure for asphalt pavements, the FWD test, dynamic cone penetrometer test, and repeated triaxial compression test were conducted on 11 sections of national highway and 8 sections of local road. Test results indicate that the tensile strain at the bottom of AC layer and AC elastic modulus were good indicators for estimating the stiffness characteristics of AC layer. For subbase layer, the BDI value and compressive strain on top of the subbase layer were appropriate to predict the structural capacity of subbase layer. The BCI value and compressive strain on top of the subgrade were found to be good indicators for evaluating the structural condition of the subgrade. The evaluation criteria for structural condition in asphalt pavements was also proposed in this paper.

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Characterization of Asphalt Pavement Distress Using Korean Pavement Research Program (한국형포장설계법을 이용한 아스팔트포장의 파손특성)

  • Lee, Kwan-Ho;Lee, Kyung-Suk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.4
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    • pp.487-493
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    • 2017
  • The main purpose of this study is to evaluate the main parameters involved in the asphalt pavement distresses, including IRI (International Rough Index), fatigue, and permanent deformation. The main parameters are the region (Seoul and Busan), traffic level, asphalt binder, maximum aggregate of surface course, thickness of the surface course and base. A total of 64 case studies were carried out under the auspices of the KPRP (Korea Pavement Research Program). From the analysis of the KPRP test results, the key factors for the asphalt pavement distress were determined. Considering the effect of one variable in the basic condition, asphalt binder was the major factor having an effect on the distresses for an AADT (Annual Average Daily Traffic) of 5000 in the Seoul area. Among the remaining factors, the results were found to be in the order of the base layer thickness (A), surface layer thickness (B), and aggregate particle size thickness (D). The same results were obtained for an AADT of 10000. In the case of Busan with an AADT of 5000, the same result was obtained as for Seoul. Among the remaining factors, the results were in the order of the base layer thickness (A), aggregate particle thickness (D), and surface layer thickness (B). Even though there was a slight difference in the effect of the traffic level and region, asphalt binder was the parameter having the greatest effect on the asphalt pavement distress. In the case where the effect of multiple parameters was analyzed, the combination of the asphalt binder and base thickness showed a relatively strong effect.

Thickness Design of Composite Pavement for Heavy-Duty Roads Considering Cumulative Fatigue Damage in Roller-Compacted Concrete Base (롤러전압콘크리트 기층의 누적피로손상을 고려한 중하중 도로의 복합포장 두께 설계)

  • Kim, Kyoung Su;Kim, Young Kyu;Chhay, Lyhour;Lee, Seung Woo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.4
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    • pp.537-548
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    • 2022
  • It is important to design the pavement thickness considering heavy-duty traffic loads, which can cause excessive stress and strain in the pavement. Port-rear roads and industrial roads have many problems due to early stress in pavement because these have a higher ratio of heavy loads than general roads such as national roads and expressways. Internationally, composite pavement has been widely applied in pavement designs in heavy-duty areas. Composite pavement is established as an economic pavement type that can increase the design life by nearly double compared to that of existing pavement while also decreasing maintenance and user costs. This study suggests a thickness design method for composite pavement using roller-compacted concrete as a base material to ensure long-term serviceability in heavy-duty areas such as port-rear roads and industrial roads. A three-dimensional finite element analysis was conducted to investigate the mechanical behavior and the long-term pavement performance ultimately to suggest a thickness design method that considers changes in the material properties of the roller-compacted concrete (RCC) base layer. In addition, this study presents a user-friendly catalog design method for RCC-base composite pavement considering the concept of linear damage accumulation for each container trailer depending on the season.