• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.1D
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• pp.91-98
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• 2011

Recently, the usage of elastic paving using EPDM Chip instead of pedestrian sidewalk blocks or permeable concrete used mostly for pedestrian walk, trails and in parks has been increassed as it can absorb impact during walking and produce wide range of colors and designs. However, the properties of EPDM Chip including elasticity and durability are decreased when exposed to ultraviolet ray and scenic paving functions through various colors are lowered due to the yellowing phenomenon. In this study, ultraviolet ray accelerated weathering test has been conducted to analyze the color changes in EPDM Chip and polyurethane resin, which are the main ingredients of elastic paving, when exposed to ultraviolet ray. The color differences are quantitatively analyzed through the color value coordination of the colored space by using the color difference scheme. The experimental results show that the color changes in BL polyurethane resin which is used most frequently at present was larger than that of EPDM Chip. Moreover, the total color difference, ${\Delta}E$, of BC polyurethane resin are 3.162 on the $14^{th}$ day of commencement of acceleration, which is 6 times greater color change resistance against ultraviolet ray than that of BL polyurethane resin with total color difference of 20.639. Therefore, the usage of BC polyurethane resin, which is manufactured to have chain-type molecular structure by using the isocyanate as the HMDI at the time of producing polymer, as binder in elastic paving with EPDM Chip is found to be a highly efficient method of restraining the color changes due to the ultraviolet ray.

• Journal of Wetlands Research
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• v.19 no.3
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• pp.359-365
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• 2017

Impermeable surfaces such as transportation land uses including roads and parking lots accumulate high heavy metals and particulate matters concentration especially during dry season which worsens the river water quality and distort the water circulation system during rainfall events. Recently, the government has been promoting policies to install Low Impact Development (LID) facilities such as permeable pavements or grass blocks in parking lots or pavements. However, transition of asphalt-paved surfaces to permeable pavement generated asphalt wastes which are detrimental to the environment and has cost implications due to its removal and disposal. Therefore this study was conducted to provide a method of constructing a cost-effective permeable pavement to reduce waste generation and cost. In this study, comparative analysis of the water circulation capacity and economic efficiency of the traditional construction method and new method proposed in this study through the lab-scale experiment. The proposed method was to make holes in existing asphalt pavements, layout geotextile fabric and permeable base media such as sand before compaction. After compaction, layout grass blocks on the compacted base media then layout sand in between each grass blocks before compaction. Apparently, there was no significant difference between the traditional installation method of permeable pavement and the proposed method in this study considering surface runoff, infiltrated volume, stored volume, and rainfall-runoff delay time. The proposed method in this study generated 86% less wastes compared to the traditional installation method and has 70% cost reduction considering asphalt removal and disposal. The construction method proposed in this study yielded similar performance compared to the traditional installation method and water circulation effect, but was proven to be less complicated and economical.

• Korean Journal of Construction Engineering and Management
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• v.11 no.6
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• pp.111-121
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• 2010

As the customer's interest for sidewalk block in the street or apartment complex is increasing, the materials of block which had been a concrete block exclusively are varied to clay paver, native rock and wood etc. Especially, the sales volume of clay paver which is environment-friendly and ergonomic is dramatically increasing every year with two digits growth rate, however, many problems like "Edge Cracking" "Freezing Breakage" "Bending Breakage" "Joint Gap" are happening frequently within a couple of hours after installation due to the durabilities. Because of the characteristics of Ceramic products, clay pavers are very easy to be broken when they are bumped against each other. In addition, they are relatively fragile by a freezing expansion breakage when exposed to water due to hydrophilic property as well as the intensity and absorptance of the products are varied with small difference from the production process such as production equipment and process control. Therefore, it costs a lot of money to repair the breakdown unless production and installation is carried out according to the strict criteria of the quality control. In this study, the symptoms of breakdown frequently happened in clay paver are classified by each type and finally the solution for this problem in the production of brick, installation and criteria of quality control through compressive strength and absorptance test is suggested.

• Journal of the Korea Institute of Building Construction
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• v.22 no.6
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• pp.607-618
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• 2022

This study involves the development of a Hwangto permeable block for rainwater storage tanks. The permeable products that form continuous voids between Hwangto binders and aggregates are fine milled slag powder, which is an industrial by-product generated during the production of Hwangto and iron, and ferro nickel slag. The properties of Hwangto permeable blocks were studied using recycled resource aggregates. The target quality is based on KSF 2394. The Hwangto permeable block for a rainwater storage tank is made of water-permeable material, and the permeability of the Hwangto permeable block itself is 0.1mm/sec or higher, with a physical performance of over 5.0MPa in flexural strength and over 20.0MPa in compressive strength. The physical properties of Hwangto permeable block for rainwater storage tanks were researched and developed. In order to prevent flooding due to heavy rain in summer and the urban heat island phenomenon due to depletion of ground water, continuous pores are formed in the block to secure a permeability function to prevent rainwater from accumulating in the pavement of the floor, and to prevent slippage for comfortable and safe storage.

• International Journal of Highway Engineering
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• v.16 no.2
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• pp.1-9
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• 2014

PURPOSES : This study aims to evaluate the performance of interlocking block pavement system for low speed highway. METHODS : Through on-site monitoring, environmental impact assessment of interlocking block pavement such as heat island reduction, traffic safety, noise pollution were evaluated as compared with asphalt pavement. Also the pavement condition and roughness were evaluated according to performance period. RESULTS : Surface temperature of interlocking block pavement was about 7 degree lower than asphalt pavement in midsummer. Compared to asphalt pavement, vehicle speed reduction effect of interlocking block pavement was about 2kph. For low speed driving, the noise pollution was measured at a similar level for both asphalt and interlocking block pavement. After 42month service period, the breakage of block was only 0.24% for the whole surveyed area. IRI of interlock block pavement was estimated within the range of 5~8m/km. CONCLUSIONS : Depending on the performance monitoring results such as heat island reduction, providing traffic safety and keeping a good pavement condition for a long service period, it assures that interlocking block pavement was applicable for low speed road.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.2
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• pp.157-166
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• 2012

Most of the roads are paved with impermeable materials such as asphalt concrete and cement concrete, and in the event of heavy rainfall, rainwater directly flows into river through a drainage hole on the pavement surface. This large quantity of rainwater directly spilled into the river frequently leads to the flooding of urban streams, damaging lowlands and the lower reaches of a river. In recent years there has been a great deal of ongoing research concerning water permeability and drainage in pavements. Accordingly, in this research, a porous polymer concrete was developed for permeable pavement by using unsaturated polyester resin as a binder, recycled aggregate as coarse aggregate, fly ash and blast furnace slag as filler, and its physical and mechanical properties were investigated. Also, 3 types of permeable polymer block by optimum mix design were developed and rainfall runoff reduction effects by permeability pavement using permeable polymer block were analyzed based on hydraulic experimental model. The infiltration volume, infiltration ratio, runoff initial time and runoff volume in permeability pavement with permeable polymer block of $300{\times}300{\times}80$ mm were evaluated for 50, 100 and 200mm/hr rainfall intensity.

• Elastomers and Composites
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• v.44 no.1
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• pp.69-75
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• 2009

Asphalt sealants for the crack repair of asphalt concrete road were prepared using waste lubricant oil in this work. The waste lubricant oil was compounded with asphalt(AP-5), SBS triblock copolymer, a tackifying agent(petroleum resin), and antioxidants. Cone penetration, softening point, ductility, elongation by tensile adhesion, and resilience of asphalt sealant compounds were measured. Cone penetration of asphalt sealant compounds increased with the increase of waste lubricant oil content while their softening point, ductility, and resilience decreased. By the addition of talc as an extender, softening point and resilience of asphalt sealants increased, but cone penetration, ductility, and elongation by tensile adhesion of those decreased with the proportion of talc content. The most economic asphalt sealant which could pass an ASTM specification could be manufactured by the big decrement of petroleum resin content.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.345-345
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• 2017

급격한 도시화 현상으로 많은 인구가 밀집되고 토지를 집약적으로 이용을 하며 시멘트 콘크리트, 블록 등 도로포장으로 인해 불투수층이 증가하여, 폭우와 홍수로 인한 인명과 재산 및 교통체증 등과 같은 다양한 피해를 야기할 수 있다. 침수피해를 발생시키는 인자들은 지표면의 침수심, 침수면적 및 지속시간 등이 있으며, 이러한 인자들을 이용하여 침수에 관한 다양한 연구들이 이루어지고 있다. 본 연구에서 연구할 지역은 도림천 지역 대림 1동, 대림 2동, 대림 3동, 신대방동의 일부분 지역을 대상으로, 침수가 발생한 2010년 강우를 활용하여 도림천 지역의 도시침수를 분석을 하였다. 침수가 일어난 원인으로는 관의 허용용량 초과로 인해 침수가 되었던 것으로 보이고 각 지선관거가 간선관거로 합류하는 과정에서 과부하로 인해 주요 간선관거에서 월류가 발생한것으로 판단된다. 이와 같이 내수배제시설 용량의 초과로 인한 침수가 발생하였을 경우 막대한 피해가 발생하게 되고 이를 저감하기 위해서는 침수심 및 침수면적 등 피해정도를 미리 예측하여 관리 할 수 있는 방안에 대한 연구가 필요하다. 본 연구는 도림천의 우수관망을 이용하여 침수해석모형인 SWMM을 활용하여 문제점들을 파악하였으며, 침수방어능력을 향상 시킬 수 있는 방안을 연구하고자 한다.

• Journal of Wetlands Research
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• v.23 no.4
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• pp.307-316
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• 2021

Due to rapidly increased urbanization, impervious area has been extended and concerns about urban flooding has been increased as well. A lot of effort has been made to restore the urban water circulation. Low Impact Development (LID) technology that consist of retention, infiltration, and evapotranspiration has begun to attract attention to simulate the hydrologic phenomenon before and after development. Many researches on the technique is being actively conducted. In this study, the effect on reducing runoff in urban catchment was analyzed and evaluated by applying LID techniques using SWMM and six scenarios. A SWMM-LID model was built for the Gasan 1 rainwater pumping station basin, and Green Roof and Permeable Pavement were selected as LID techniques to be applied. As a result, the reduction effect of the permeable pavement was larger than green roof. In the future, the results could be used to design a LID facility using the characteristics of the watershed, and other urban water resource factors such as river and groundwater levels that affect each other should be considered, so that the entire system can be considered.

• Journal of the Korean Geotechnical Society
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• v.39 no.10
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• pp.41-48
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• 2023

The presence of abnormalities in the subgrade of roads poses safety risks to users and results in significant maintenance costs. In this study, we aimed to experimentally evaluate the temperature distributions in abnormal areas of subgrade materials using infrared cameras and analyze the data with machine learning techniques. The experimental site was configured as a cubic shape measuring 50 cm in width, length, and depth, with abnormal areas designated for water and air. Concrete blocks covered the upper part of the site to simulate the pavement layer. Temperature distribution was monitored over 23 h, from 4 PM to 3 PM the following day, resulting in image data and numerical temperature values extracted from the middle of the abnormal area. The temperature difference between the maximum and minimum values measured 34.8℃ for water, 34.2℃ for air, and 28.6℃ for the original subgrade. To classify conditions in the measured images, we employed the image analysis method of a convolutional neural network (CNN), utilizing ResNet-101 and SqueezeNet networks. The classification accuracies of ResNet-101 for water, air, and the original subgrade were 70%, 50%, and 80%, respectively. SqueezeNet achieved classification accuracies of 60% for water, 30% for air, and 70% for the original subgrade. This study highlights the effectiveness of CNN algorithms in analyzing subgrade properties and predicting subsurface conditions.