• International Journal of Highway Engineering
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• v.8 no.4 s.30
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• pp.25-36
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• 2006

Through field surveys and evaluation on several widened concrete pavements, issues on construction and design related problems are broken down into three categories to be discussed; poor smoothness, influence of traffic vibration on concrete curing, and poor connection to the existing pavement. There are many places where about 100mm only of the marginal strip is removed and where defects such as widening and faulting are observed. Also cracks arise again from the patched areas due to stress concentration near the joint. Roughness on the widened concrete pavement was evaluated and there are some stations where the smoothness limit is over passed. For design consideration, shortage of the required force in the tie-bar is expected in case of road widening specially from 3 lanes to 4 lanes. Finally the average pull-out force of specimens made from the current practice was about 57% of the required force. New connecting methods were suggested in this study.

• International Journal of Highway Engineering
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• v.15 no.4
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• pp.65-73
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• 2013

PURPOSES : As a research to develop a cement treated base course for an airport pavement which can enhance its drainage, this paper investigated the strength, infiltration performance and durability of the pervious concrete with respect to maximum coarse aggregate sizes and compaction methods. METHODS : This study measured compressive strength, infiltration rate, continuous porosity and freeze-thaw resistance of pervious concrete specimens, which were fabricated with five different compaction methods and different maximum aggregate sizes. In addition, in order to reduce the usage of Portland cement content and to enhance environment-friendliness, a portion of the cement was replaced with Ground Granulated Blast Furnace Slag (GGBS). RESULTS: Compressive strength requirement, 5 MPa at 7 days, was met for all applied compaction methods and aggregate sizes, except for the case of self-compaction. Infiltration rate became increased as the size of aggregate increased. The measured continuous porosities varied with the different compaction methods but the variation was not significant. When GGBS was incorporated, the strength requirement was successfully satisfied and the resistance to freezing-thawing was also superior to the required limit. CONCLUSIONS: The infiltration rate increased as the maximum size of aggregate increased but considering construct ability and supply of course aggregate, its size is recommended to be 25mm. With the suggested mix proportions, the developed pervious concrete is expected to successfully meet requirements for strength, drainage and durability for cement treated base or subbase course of an airport pavement.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.3
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• pp.71-83
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• 2008

In this paper, the basic principle, the application and the limitation of Infrared thermography technique to detect defects in different kinds of concrete structures are reviewed. Considered are voids beneath the concrete surface with experiments, delamination between concrete surface and fiber reinforced polymer sheet, the deterioration of steel bars in reinforced concrete, surface defects in historical buildings, pavements, bridges, and railway track graves. As a result, we conclude that infrared thermography methods are useful for fast detecting defects; however, they are influenced by environmental factors, specially temperature. Therefore it is recommended to use the infrared thermography technique with other NDT equipments to expect better result.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.3D
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• pp.279-288
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• 2010

Recently, researches on the performance warranty contracting has been going on to improve construction quality in road pavement area. The performance warranty contracting gives construction companies opportunity to select materials and methods freely while asks them to maintain a certain level of performance during a given period. To introduce the performance warranty contracting in Korea, lots of research results on performance indicator and threshold value of asphalt pavement have been made to be included in the warranty specification. However, research effort on the performance indicator and threshold value of concrete pavement which is commonly constructed in expressway and national highway has not been enough. In this study, the warranty duration, performance indicator, and threshold value of the concrete pavement were investigated by reviewing literatures on cases of the performance warranty contracting in European countries and states of the US. Major distresses influencing the performance of jointed concrete pavement were investigated and analyzed to be compared to the warranty duration, performance indicator, and threshold value of foreign countries.

• International Journal of Highway Engineering
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• v.13 no.1
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• pp.139-148
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• 2011

Asphalt concrete overlay method is used by general maintenance and rehabilitation of construction for aged concrete pavement in Korea. However, in case of the AC overlay method to extend service life of the existing concrete pavements, various distresses of reflection crack, pothole and rutting are the typical problems of the asphalt overlay on existing concrete pavement since it has different physical characteristics between asphalt overlay and existing concrete pavement. To achieve this, application of concrete overlay method is required instead of AC overlay method. Concrete overlay method has advantages that can reduce maintenance cycle and costs since it has excellent bearing value for heavy vehicles and no rutting. However, technical problems of detour road construction, traffic control and other disadvantages happened by long curing time. Thus, in this study and experimental research were launched to evaluate the workability, durability and resistance against environmental loading of Very Rapid Hardening Acrylic Polymer Modified Concrete(VRH-APMC) for application of bonded concrete overlay method. Test results showed that the compressive and bond strength were exceed 21MPa and 1.4MPa of target strength after four hours for rapid traffic opening properties. And tests of resistance against environmental loading results showed that VRH-APMC secured excellent durability. Thus, it was known that VRH-APMC was suitable material for large scale bonded concrete overlay method, and it was possible to use maintenance and rehabilitation method which needs enough workability and rapid traffic opening.

• International Journal of Highway Engineering
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• v.18 no.6
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• pp.131-136
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• 2016

OBJECTIVES : The objective of this research is to determine the integrity of pavement structures for areas where voids exist. Furthermore, we conducted the study of voided-area analysis and remaining life prediction for pavement structures using finite element method. METHODS : To determine the remaining life of the existing voided areas under asphalt concrete pavements, field and falling weight deflectometer (FWD) tests were conducted. Comparison methods were used to have better accuracy in the finite element method (FEM) analysis compared to the measured surface displacements due to the loaded trucks. In addition, the modeled FEM used in this study was compared with well-known software programs. RESULTS : The results show that a good agreement on the analyzed and measured displacements can be obtained through comparisons of the surface displacement due to loaded trucks. Furthermore, the modeled FEM program was compared with the available pavement-structure software programs, resulting in the same values of tensile strains in terms of the thickness of asphalt concrete layers. CONCLUSIONS : The study, which is related to voided-area analysis and remaining life prediction using FEM for pavement structures, was successfully conducted based on the comparison between our methods and the sinkhole grade used in Japan.

• International Journal of Highway Engineering
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• v.7 no.2 s.24
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• pp.77-86
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• 2005

A spalling model for jointed connote pavements(JCP) was developed using the data of distresses, climates, and materials at the sections of long-term pavement performance(LTPP) investigation. The total of forty-four spatting distress data was collected at twenty-two JCP LTPP sections in 1999 and in 2004. In addition, the data of climates, geometric shapes of the slabs, and material properties was also collected at those times. Factors significantly influencing the spalling distress were found by a sensitivity analysis for the data. Consequently, a spatting model was developed by a multi-regression analysis for the factors. The model showed reasonable trend of the spatting development comparing to other foreign models.

• International Journal of Highway Engineering
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• v.20 no.4
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• pp.35-46
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• 2018

PURPOSES : The purpose of this study is to compare the lane curing time of natural drying and a lane drying device when painting lines on a highway. METHODS : The painting process was carried out in July 2015 and September 2015, respectively, for the Gimcheon IC - Gimcheon JC. After the painting, measurements were obtained three times at six measurement points located at 20 m intervals on the shoulder line and the dividing line. The curing time was measured for natural drying and drying using a lane drying device, and compared for different pavement types (asphalt, concrete) and paint types (waterborne paint, methyl methacrylate paint). RESULTS : The results of the lane curing time comparison on the highway are as follows. The combination of asphalt and methyl methacrylate paint cured more rapidly during both the natural drying and drying using the lane drying device. Finally, it was cured at least 32.2% and 40.7% faster when using a drying device than in natural drying. CONCLUSIONS : The comparison of lane curing time of the highway showed that the combination of asphalt and methyl methacrylate paint cured more rapidly when using both natural drying and a lane drying device.

• 한국도로학회:학술대회논문집
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• 2008.10a
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• pp.93-102
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• 2008

An energy based crack growth model is developed in this study to simulate the propagation of top-down cracking in asphalt pavements. A viscoelastic fracture mechanics approach, generalized J integral, is employed to model the crack growth of asphalt concrete. Laboratory fatigue crack propagation tests for three different asphalt mixtures are performed at various load levels, frequencies and temperatures. Disk-shaped specimens with a proper loading fixture and crack growth monitoring system are selected for the tests. It is observed from the tests that the crack propagation model based on the generalized J integral is independent of load levels and frequencies, while the traditional Paris' law model based on stress intensity factor is dependent of loading frequencies. However, both models are unable to take care of the temperature dependence of the mixtures. The fatigue crack propagation model proposed in this study has a good agreement between experimental and predicted crack growth lives, which implies that the energy based J integral could be a better parameter to describe fatigue crack propagation of viscoelastic materials such as asphalt mixtures.

• International Journal of Highway Engineering
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• v.10 no.2
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• pp.145-157
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• 2008

Load transfer efficiency (LTE) reflects the structural performance of doweled and undoweled joints of Jointed Concrete Pavement (JCP). A 3-dimensional (3-D) model of JCP was built using ABAQUS software in this study. Three concrete slabs were placed on bonded sublayers composed of a base and subgrade. Spring elements were used to connect the adjacent slabs at joints. Different spring constants were input to the model to simulate different joint stiffness of the concrete pavement. The LTE of the joint increased with an increase of the spring constant. The effects of material properties and geometric shape on the behavior of JCP were analyzed using different elastic modulus and thickness of the slab and base in the modeling. The results showed the elastic modulus of the subgrade affected the behavior of the slab and LTE more than that of the base and the thickness of the slab and base. The effects of a negative temperature gradient on the behavior of the slab and LTE were more than that of positive and zero temperature gradients. Joints with low stiffness were more sensitive to the temperature gradient of the slab.