• Scientific Paper

    Characteristics of warm mix asphalt mixtures containing reclaimed asphalt pavement (RAP) by content of waste glass aggregate (WGA)

    잔골재 일부를 폐유리로 대체한 준고온 순환 아스팔트 혼합물 특성 평가

    Youngjin Jo, Jieun Lee, Wonbae Kim, Kwang W. Kim and Sungun Kim

    조영진·이지은·김원배·김광우·김성운

    This study performed to apply waste glass aggregate (WGA) to manufacture for paving asphalt mixture containing reclaimed asphalt pavement (RAP). The WGA ... + READ MORE
    This study performed to apply waste glass aggregate (WGA) to manufacture for paving asphalt mixture containing reclaimed asphalt pavement (RAP). The WGA below 5 mm which is replaced the partial of natural fine aggregate (NFA) was used to manufacture recycled warm mix asphalt mixture (RWMA) that contained RAP, crumb rubber modifier (CRM), waste polyethylene (W-PE) and warm mix additive. Warm mix additive used in study, which was invented using several core materials, such as waxes and oil, and other substances, was used to manufacture WMA mixture. WMA mix design was conducted to use WGA substituted for the NFA contents of 5, 10, 15% in mixture and determined optimum asphalt content (OAC) by dosage of the WGA, and then compared performance with normal asphalt mixture. The specimens of RWMA were prepared with the OACs, and rutting resistance, crack resistance, and moisture sensitivity were evaluated by performing deformation strength (SD), dynamic stability (DS), indirect tensile strength (ITS), tensile strength ratio (TSR), and deformation strength ratio (SDR). As a result, OACs of RWMA decreased as increasing WGA contents in mixture. Performances of RWMA for base layer (BB-2) such as SD, ITS, toughness, TSR and SDR, were satisfied the specification of the Ministry of Land, Infrastructure and Transport, even if WGA was substituted for NFA up to 15%. This was believed to be due to the increase stiffness by aged binder in RAP and the influence of CRM, W-PE used as modifiers, and warm mix additives. - COLLAPSE
    December 2020
  • Scientific Paper

    Selection of the disaster prevention road considering earthquake risk

    지반의 지진위험도를 고려한 방재도로의 선정

    Jae-Soon Choi

    최재순

    In Pohang, several roads has been damaged by liquefaction occurrence and attention has been paid to disaster prevention roads. This study is ... + READ MORE
    In Pohang, several roads has been damaged by liquefaction occurrence and attention has been paid to disaster prevention roads. This study is a case study using GIS mapping for disaster prevention road in Pohang where the biggest earthquake damage occurred in Korea in 2017. To simulate the earthquake risk of road, we predicted liquefaction potential and collapse of old non-seismic buildings against two earthquakes with return period 500 and 1,000 years. For GIS simulation, liquefaction assessment was conducted based on the survey data of the regional area. Based on the results, the liquefaction potential index as a liquefaction risk and dangerous old roadside buildings under earthquake loading were also shown on the map. - COLLAPSE
    December 2020
  • Scientific Paper

    A review on quality control index of new asphalt pavement construction
    Mithil Mazumder, Hyun Hwan Kim, Kyu-Dong Jeong and Soon-Jae Lee
    Maintenance and repair influence the life cycle costs of highway construction and increase the cost of transportation agency. Therefore, it is important ... + READ MORE
    Maintenance and repair influence the life cycle costs of highway construction and increase the cost of transportation agency. Therefore, it is important to execute a new pavement which can be used for a long time with a minimal maintenance program. As a result, the implementation of quality control at each stage of the construction process of new pavement can ensure a stable road of high quality. This paper presents the quality control index for the new hot mix asphalt (HMA) paving. In-depth discussions have been provided for quality control of material selection (aggregate and asphalt), asphalt mixture, its laying process and compaction of new paving works. Recommendations and guidelines are given for the personnel in charge of various stages of the construction process. - COLLAPSE
    December 2020
  • Scientific Paper

    Performance evaluation of Double Recycled Reclaimed Asphalt Pavement (DRRAP) at low temperature
    Ki-Hoon Moon
    To mitigate environmental issue and budget reduction problem application of recycled asphalt material so called Reclaimed Asphalt Pavement (RAP) is essential in ... + READ MORE
    To mitigate environmental issue and budget reduction problem application of recycled asphalt material so called Reclaimed Asphalt Pavement (RAP) is essential in asphalt pavement industry. For many decades, many pavement agencies successfully applied RAP on the actual asphalt pavement construction. Moreover, interest and application of Double Recycled Reclaimed Asphalt Pavement (DRRAP) got more attractions for pavement engineer for many years. However, it needs to be known that stiffer and more brittle characteristics of RAP compared to the conventional asphalt pavement material provide negative effect on pavement performance especially at low temperature condition. In this paper, performance evaluation of DRRAP compared to the conventional Single Recycled Reclaimed Asphalt Pavement (SRRAP) materials at low temperature was performed by means of simple mathematical approach. As a result, possibility of DRRAP application on actual pavement work was derived. - COLLAPSE
    December 2020
  • Scientific Paper

    Laboratory study on asphalt mixture modified by polyacronitrile fibres and reclaimed asphalt planings
    Chiara Riccardi, Michael P. Wistuba and Di Wang
    In this laboratory study, combined effects of polyacronitrile fibres and reclaimed asphalt planings on performance properties of asphalt mixtures were investigated. Performance ... + READ MORE
    In this laboratory study, combined effects of polyacronitrile fibres and reclaimed asphalt planings on performance properties of asphalt mixtures were investigated. Performance properties of six asphalt mixtures in total were comparatively analyzed, always considering a standard mix design concept for asphalt binder courses. Three asphalt mixtures were prepared with fresh materials only: two asphalt mixtures were produced without incorporating fibres, one using unmodified plain binder of the type 50/70 Pen Grade (in the following used as reference mixture and therefore identified as Ref.), the other one using polymer modified binder of the type 40/100-65 Pen Grade (identified as PmB). The third one was a fibre reinforced asphalt mixture (FRAM), composed of 50/70 Pen Grade binder, and 0.15% by total weight of the asphalt mixture of polyacronitrile fibres added directly in the drum to the aggregates. In addition, three more asphalt mixtures were prepared similarly, but 50% of the total mass was replaced by recycled material originating from reclaimed asphalt planings (RAP). These three mixtures containing RAP were identified as Ref.+RAP, PmB+RAP, and FRAM+RAP. All six asphalt mixtures were subjected to performance tests: wheel tracking tests were conducted in the high temperature range to study permanent deformation resistance, indirect tensile tests were conducted at intermediate temperatures to study fatigue resistance, and thermal stress restrained specimen tests were conducted at low temperatures to study resistance to thermal cracking. Test results indicate that asphalt mixture modification by polyacronitrile fibres and reclaimed asphalt planings results in acceptable performance properties, and potentially improves high and intermediate temperature properties. - COLLAPSE
    December 2020
  • Technical Notes

    A study on the intelligent asphalt pavement system

    인텔리젼트 아스팔트 포장 시스템 조사 연구

    Kyu-dong Jeong, Je-Won Kim, Woo-Sung Yum and Sung-Do Hwang

    정규동·김제원·염우성·황성도

    Internationally, the Intelligent Pavement System is applied to rollers and asphalt paver, and in the United States it is integrated into VETA ... + READ MORE
    Internationally, the Intelligent Pavement System is applied to rollers and asphalt paver, and in the United States it is integrated into VETA software. Based on the GNSS location information, the system can measure the speed and temperature when paving, and reduce job-site quality variation by measuring the number of rolling, temperature, speed, and stiffness responses values. The stiffness values is often highly correlated with the results of the nuclear density test. In order to apply intelligent pavement system in Korea, it is necessary to monitor the major elements in the asphalt mixture production, construction, quality control and inspection in real time, and manage them with a unified system. - COLLAPSE
    December 2020
  • Scientific Paper

    A study on cantabro loss by test conditions for porous asphalt mixture

    배수성 아스팔트 혼합물의 시험환경 변화에 따른 칸타브로 손실률 연구

    Il Hwan Kang, Young Geon Lee, Tae Soon Park and Ki Hoon Moon

    강일환·이영건·박태순·문기훈

    This study was conducted to confirm the change in the cantabro loss according to the test conditions. The test temperature of the ... + READ MORE
    This study was conducted to confirm the change in the cantabro loss according to the test conditions. The test temperature of the cantabro test was 20°C and –20°C and a dry sample and a wet sample were used. 4 types of pre-mix type high-viscosity binder and 1 type of plant-mix type high-viscosity binder were used and specimens were prepared with 75 blows marshall compaction and 20±5% porosity. Dry samples were cured at test conditions(20°C and –20°C) for 24hours in a constant temp&humi control chamber. Wet samples were immersed in a constant water bath at 60°C for 24hours and then cured for 6hours in a constant temp&humi control chamber. As a results of test, the 20°C cantabro loss of the dry sample did not significantly discriminate according to the PG grade, but the 20°C cantabro loss of the wet sample was confirmed to be different. In the –20°C cantabro test, the lower the PG grade, the smaller the cantabro loss occurred, and in the case of the wet sample, there was no significant difference from the dry sample. - COLLAPSE
    December 2020
  • Scientific Paper

    A study on proposal of standard sample for marshall stability test

    마샬안정도 시험기의 적정성을 위한 표준시료 제안 연구

    Junseong Choi, Jinsu Kim and Sangjin Kim

    최준성·김진수·김상진

    In addition to the adequacy evaluation of existing equipment for Marshall stability manufactured in Korea, a standard sample is required to verify ... + READ MORE
    In addition to the adequacy evaluation of existing equipment for Marshall stability manufactured in Korea, a standard sample is required to verify the new Marshall stability test using IoT system in the era of the 4th industrial revolution. In this study, a standard sample concept was established by selecting polyurethane, which can be produced with the same composition ratio, as the standard material, since comparative analysis is not possible with a general asphalt mixture. In order to evaluate the adequacy and validity of the standard sample proposed in this study, the UTM experiment and experiments for the resting period were conducted, and a comparative study between the equipments through the Round-Robin Test was conducted to confirm the applicability of the standard sample. From the comparative tests, the repeatability of the standard sample was confirmed. And it was found that the standard sample can be used to compare and analyze equipments, as the Round-Robin test shows the relative error of 5.1% for the Marshall stability test, 0.5% for the indirect tensile strength test, and 6.5% for the Kim test. In the future, the standard sample proposed in this study requires additional research on the standardization and the reference value through the round-robin test of domestic equipments. - COLLAPSE
    December 2020