• International Journal of Highway Engineering
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• v.17 no.6
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• pp.19-26
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• 2015

PURPOSES : This study intends to develop an inorganic soil pavement material using industrial by-products and to evaluate its applicability as a road pavement material. METHODS : In this study, a compressive strength experiment was conducted based on the NaOH solution molarity and water glass content to understand the strength properties of the soil pavement material according to the mixing ratio of alkali activator. In addition, the strength characteristic of the inorganic soil pavement material was analyzed based on the binder content. The performance of the soil pavement was evaluated by conducing an accelerated pavement test and a falling weight deflectometer (FWD) test. RESULTS : As a result of the soil pavement material test based on the mixture ratio of alkali activator, it was identified that the activator that mixed a 10 M NaOH solution to water glass in a 5:5 ratio is appropriate. As a result of the inorganic soil pavement materials test based on the binder content, the strength development increased sharply when the amount of added binder was over 300 kg; this level of binder content satisfied 28 days of 18 MPa of compression strength, which is the standard for existing soil pavement design. According to the measured results of the FWD test, the dynamic k-value did not show a significant difference before or after the accelerated pavement testing. Furthermore, the effective modulus decreased by approximately 50%, compared with the initial effective modulus for pedestrian pavement. CONCLUSIONS : Based on these results, inorganic soil pavement can be applied by changing the mixture proportions according to the use of the pavement, and can be utilized as road pavement from light load roads to access roads.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.1164-1171
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• 2010

Korea is considered to be a seasonal frozen soil area that is thawed in the spring, and most of the area is frozen in winter as to the characteristic of geography. In the current design codes for anti-freezing layer, the thickness of anti freezing layer is calculated by freezing depth against the temperature condition. Therefore, they have a tendency of over-design and uniform thickness without the considerations of thermal stability, bearing capacity and frost susceptibility of materials. So, it is essential for studying the appropriateness and bearing capacity besides the seasonal and mechanical properties of pavement materials to take a appropriate and reasonable design of the road structure. In this research, the evaluation of frost susceptibility on subgrade, ant-freezing layer, sub base was conducted by means of the mechanical property test and laboratory field road model downed scale experiment. The temperature, heaving amount, heaving pressure and unfrozen water contents of soil samples, the subgrade, anti-freezing layer, sub base soils of highway construction site, were measured to determine the frost susceptibility.

• International Journal of Highway Engineering
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• v.16 no.4
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• pp.11-19
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• 2014

PURPOSES: This study is to suggest the improvement for bus rapid transit system in Seoul METHODS: The maintenance cost for bus lane damages and plastic deformations are increased by bus passing speed, heavy bus weight, and climate change (localized torrential downpour, subtropical climate) and the accident risk has been increased. RESULTS: Recent analysis of pavement damage indicates that bus lane damage caused by heavy weight is overwhelming and it is urgent to prepare countermeasures. CONCLUSIONS : Pavement data of bus rapid transit system, bus transit numbers and pavement damage elements were analyzed. By analyzing pavement maintenance, design and construction, the countermeasures for the improvement of bus lane pavement and effective maintenance were suggested.

• Journal of Korean Society of Rural Planning
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• v.14 no.1
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• pp.1-7
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• 2008

Recently, brick pavement were widely introduced on the pavement in rural area. A variety of vision effects can be created from patterns of brick pavement. However, in most of brick pavement works, human psychological characteristics were not concerned. The purpose of this research was to discover psychological effect on brick pavement pattern. The results of the research can be summarized as follows: 1)Psychological impression on brick pavement pattern is similar among man and woman groups. 2)Stack bond and running bond pattern have a simple, relaxed, organized, and comfortable psychological characteristics. Basket weave & stack bond pattern has a simple and organized psychological characteristic. Herringbone bond pattern has a complex, dislike and uncomfortable psychological characteristic. Pinwheel bond pattern has a highly complex psychological characteristic. Basket weave and Basket weave variation bond pattern have a common psychological characteristic. 3)Employment of brick pavement pattern on this research is not highly preferred, hence it is necessary to develop a brick pavement patterns that have human psychological characteristics be concerned.

• International Journal of Highway Engineering
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• v.10 no.4
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• pp.79-89
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• 2008

The pavement performance model is the most important factor to determine the pavement life in the mechanistic-empirical pavement design guide (MEPDG). As part of Korean Pavement Research Program (KPRP), the Korean Pavement Design Guide (KPDG) is currently being developed based on mechanistic-empirical principle. In this paper, the rutting prediction model of asphalt mixtures, one of the pavement performance model, has been developed using triaxial repeated loading testing data. This test was conducted on various types of asphalt mixtures for investigating the rutting characteristics by varying with the temperature and air void. The calibration process was made for the coefficients of rutting prediction model using the accelerated pavement testing data. The accuracy of prediction model can be increased when by considering the effect of individual rutting properties of materials rather than shear stresses with depths.

• International Journal of Highway Engineering
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• v.2 no.2
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• pp.139-148
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• 2000

Currently existing Accelerated Pavement Testing (APT) systems developed in several countries have been employed mainly to test the performance of asphalt pavement. Meanwhile, the length of concrete pavement is similar to that of asphalt pavement in expressways of Korea. and is expected to increase due to its durability and compatibility to our weather condition. To meet the society's demand of having our own APT system which can examine the long-term performance of concrete pavement, a contract study to develop Korea Accelerated Loading and Environment Simulator (KALES) for concrete pavement has been performed for 3 years from 1997 through 1999. Through the project, a detailed design was Peformed for the KALES system in which the entire structure of KALES, loading mechanism, wandering mechanism, suspension system, driving system were proposed. Also in advance to design a full-scale KALES system, a sample scale model was manufactured and tested for operating motion and force distribution. It is evident that the proposed prototype KALES system will provide higher degree of traffic simulation and durable operation, based on the satisfactory fatigue analysis.

• Land and Housing Review
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• v.10 no.4
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• pp.51-59
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• 2019

The government is encouraging the notice of obligatory reclaimed asphalt as a result of the economic and social positioning of green growth to reduce the amount of waste resources and to solve natural resource problems by recycling continuously generated waste resources. However, it is necessary to develop application guideline for each application to apply reclaimed asphalt to the site because quality control of the reclaimed asphalt is difficult and the specifications are ambiguous as well. Therefore, in this study, the mix design, quality test, performance test, and finite element analysis about reclaimed Asphalt Pavement were conducted to develop application guideline for reclaimed hot asphalt. The mix design was carried out for the comparative general hot mix asphalt mixture, the reclaimed hot mix asphalt mixture using the additive, and the reclaimed hot mix asphalt mixture without the additive. Indirect tensile strength and tensile strength ratio tests were used to characterize the reclaimed hot mix asphalt mixture. Using the results of dynamic modulus test and FWD test for KPRP analysis and finite element analysis, the performance life was evaluated for general pavement and pavement using recycled aggregate. Finally, the life cycle cost analysis was used to compare and analyze the economics of reclaimed asphalt concrete pavement.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.5
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• pp.43-51
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• 2004

Recently, the importance of choosing correct pavement materials has been increasing in urban spaces and streets. Much research regarding the pavement theory and construction method have been conducted, but analysis in terms of human psychological character has not yet been performed. The purpose of this study is to investigate the psychological characters to 12 pavement materials, that are commonly used in our urban spaces and streets. The results of the psychological character for each pavement material can be summarized as follows: 1. The psychological characters to each pavement material were as follows: ① Clay embodies a natural, traditional, soft and intimate psychological character; ② Pebble stone has a natural, hard, cool and intimate psychological character; ③ Turf grass incorporates an intimate and soft psychological character; ④ Ceramic brick has an artificial and hard psychological character; ⑤ Tile pavement has a modern, artificial, hard and cool psychological character; ⑥ Water permeable concrete has a modern and artificial psychological character; ⑦ Flag stone has a natural psychological character; ⑧ Granite has a modern and artificial psychological character; ⑨ Portland concrete has an artificial and hard psychological character; ⑩ Small compacted brick has an artificial, dynamic and modern psychological character; ⑪ Wood block pavement has a natural and traditional psychological character; ⑫ Asphalt concrete pavement has a modern, hard and artificial character. 2. On the results of the cluster analysis regarding psychological indexes for 12 pavement materials, pavement materials were categorized in 3 clusters. Among them, one cluster was mainly used as the most popular pavement material in our urban spaces and streets. From this point of view, psychological character for pavement material in our urban spaces and streets was not as various as we expected. 3. In conclusion, the proper selection of pavement materials was very important and the factors affecting the human psychological character should be considered in the design of urban spaces and streets.

• Journal of the Korean GEO-environmental Society
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• v.3 no.1
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• pp.57-66
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• 2002

Generally, the California Bearing Ratio(CBR) for the material of subgrade is estimated without considering the anti-frost layer into the subgrade layer when pavements are designed. A pavement structure is determined according to the CBR. However, recently the design method taking the anti-frost layer into the subgrade layer is getting prevail. It makes the top of the subgrade layer strengthen and the thickness of the road pavement structure decreased. By the way, some confusion may be caused because theoretically the general equation for the mean CBR to combine the material of the subgrade layer and anti-frost layer have not been developed well. In this paper, laboratory and field CBR tests were performed to estimate of the mean CBR for the subgrade layer including the anti-frost layer. From the basis of the test results, modified equation which is calculating the mean CBR of the subgrade layer has been proposed. Finally, economical efficiency was considered by comparing the pavement thickness with the road pavement design using CBR of the subgrade layer alone and the road pavement design using the mean CBR including the anti-frost layer.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.9
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• pp.4199-4204
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• 2011

The dynamic modulus of hot mix asphalt is one of the important indicators to evaluate the durability and performance of asphalt pavement. In resent, the dynamic modulus is suggested by a key property of asphalt pavement design and analysis in AASHTO 2002 Design Guide and Korean Pavement Research Project(KPRP). Master curve from laboratory test results should be needed for pavement design and analysis. The process to get the master curve is standardized. But, there are some setup and testing error at low temperature(-$10^{\circ}C$) and high temperature ($55^{\circ}C$). In this paper, a simplified process which is used 3 testing temperatures (5, 21, 40) is adopted to get the master curve. Comparison was carried out for standard process and simplified process. The suggested process can be used to get the master curve of asphalt pavement, even though some difference was shown at high temperature.