PURPOSES : In this study, the basis for improving the maintenance method of road pavement in Jeju Island, where deterioration is accelerating, was presented through field construction and analysis of various combinations of maintenance methods. METHODS : Construction was performed on Jeju Island's Aejo Road, which has high traffic and frequent early damage, using various asphalt mixtures mainly applied in Jeju Island, with different maintenance cross-sections depending on the level of repair. The quality and performance of the asphalt mixture collected during construction were evaluated, and MEPDG was used to analyze the service life according to the type and maintenance level of the mixture. RESULTS : While the mixture for the surface layer satisfied the quality standards and had excellent rutting and moisture resistance performance, the asphalt mixture for the intermediate and base layer did not satisfy the quality standards such as air voids, so it was judged that quality control was necessary during production. The section repaired to the base layer was found to be advantageous for the integrated behavior of the pavement and had the best structural integrity. As a result of predicting the service life, the estimated life of the section where only the surface layer was repaired was analyzed to be approximately 7 years, the section where the intermediate layer was repaired was 14.5 years, and the section where the entire section up to the base layer was repaired was analyzed to be 18 years. CONCLUSIONS : In Jeju Island, where deterioration is accelerating, it was analyzed that when establishing a maintenance plan, it is necessary to consider repairing the middle and base floors in order to secure the designed life of 10 years.

PURPOSES : The purpose of this study was to reduce greenhouse gases and prevent potholes on roads by evaluating the performances of hot and warm mixed asphalt mixtures. METHODS : Quality tests were conducted using an appropriate aggregate ratio of the asphalt mixture. The tests for comparing the warm mixed asphalt mixture are the indirect tensile strength and toughness, Marshall stability and flow, tensile strength ratio, and dynamic immersion test. A performance evaluation was conducted using a mixture that satisfied the quality test results. A performance evaluation test was also conducted using the dynamic modulus and Hamburg wheel tracking test. To analyze the performance based on the amine content, the performance was compared with that of a hot mixed asphalt mixture. RESULTS : All tests for the mixture results satisfied the standard values. The optimal amine content was analyzed through the high and low frequencies of the dynamic modulus test results and stripping inflection point with the final rut depth of the Hamburg wheel tracking test. The dynamic modulus test results demonstrated better crack resistance and plastic deformation when a high amine content ratio was used. The Hamburg wheel-tracking test showed water resistance and plastic deformation resistance. The test results of the Hamburg wheel tracking indicated better deformation resistance and water resistance when a high amine content ratio was used. CONCLUSIONS : The plastic deformation and crack resistance increased with an increase in amine content. Analysis of the comprehensive test revealed that the optimal amine content was between that of additives B(50%) and C(65%). Tests with a granular amine content are planned to confirm the specific components. Also planned are a simplified viscoelastic continuum damage test and a semicircular bending test to evaluate the performance better.

PURPOSES : This study compared the performance evaluation of a hot mix asphalt (HMA) and asphalt mixture of a warm-antistrip agent. METHODS : A mix design applying Korean standards was conducted to evaluate the performance evaluation. Thereafter, the quality standard evaluation of the asphalt mixture produced was conducted, and if all quality standards were satisfied, a performance evaluation was conducted. Types of performance evaluation included the Hamburg wheel tracking test and dynamic modulus test. RESULTS : As a result of the Hamburg wheel tracking test, the asphalt mixture with a warm-antistrip agent obtained a lower sedimentation value at 10000 times and 20000 times. This result is considered to have higher plastic deformation resistance of the asphalt mixture with a Warm-antistrip agent than HMA. The U.S. Department of Transportation stipulates that plastic deformation resistance is excellent if the asphalt mixture does not exceed 20,000 times the precipitate of 20 mm. Therefore, we confirmed that the plastic deformation resistance of the asphalt mixture with a warm-antistrip agent was excellent. Additionally, the master curve was analyzed by synthesizing the results of the dynamic modulus test. When analyzing the low load cycle at the bottom left of the master curve, the dynamic modulus value of the master curve was higher in the asphalt mixture with a warm-antistrip agent than in the HMA. In addition, when analyzing the high load cycle part, the dynamic modulus of the HMA was measured to be higher than that of the asphalt mixture with a warm-antistrip agent. Accordingly, the resistance to fatigue cracking of the asphalt mixture with a warm-antistrip agent was considered superior to that of the HMA. CONCLUSIONS : As a result, we confirmed that the asphalt mixture with a warm-antistrip agent that satisfies the Korean quality standards had better plastic deformation and fatigue resistance for all performance evaluation tests conducted in this study than the HMA. However, since the Hamburg wheel tracking test did not significantly differ in the amount of sedimentation in the performance evaluation tests and the mixture using one additive was compared with HMA, studies on the effects of various additives containing warm-antistrip agents are required.

PURPOSES : In this study, the results of an intensive field survey of a composite pavement applied to an expressway in Korea are analyzed. The results are intended to be used as basic data for evaluating the composite pavement and for preparing quality control measures through a review and analysis of the change in the state of the tensile bonding strength of the composite pavement. METHODS : To evaluate, repeated field coring and indoor tensile bonding strength evaluations are conducted for five years, and the commonality evaluation of pavement using pavement condition investigation equipment is conducted annually. RESULTS : The results of this study show that the degree of reflective crack generation varies depending on the type of concrete pavement and type of asphalt mixture applied to the intermediate layer, and that the CRCP composite pavement exhibits better initial commonality than the JCP composite pavement. In addition, it is confirmed that the composite cross-section pavement section with MASTIC applied as an intermediate layer shows excellent adhesion performance between the lower concrete layers from the beginning of construction in all sections, as well as satisfied the quality control standards for good pavement and tensile adhesion even after approximately five years of public use. CONCLUSIONS : Based on a follow-up survey of the composite pavement testing sections, it is confirmed that the section constructed with the MASTIC intermediate layer and CRCP satisfies the quality control standards for good pavement conditions and tensile adhesion even after approximately five years of public use.

PURPOSES : The use of reclaimed aggregate has been recently increasing with the increase in the amount of waste asphalt concrete. The application of these materials can reduce the properties of the asphalt pavement when compared with the case when recycled aggregate is not used. The objective of this study is to evaluate the performance of the asphalt mixtures with various mix ratios of reclaimed aggregate. METHODS : To measure the performance, the following tests using the mixtures prepared in accordance with the Korea Standards were conducted: Hamburg wheel-tracking test, third-scale model mobile loading simulator test, and dynamic modulus test. RESULTS : The test results of the Hamburg wheel-tracking test indicate that the water resistance was similar in each mixture and the plastic deformation resistance was good in the high-ratio reclaimed aggregate mixture. In the case of the third-scale model mobile loading simulator test, the plastic deformation demonstrated a high resistance in the high-ratio reclaimed aggregate mixture. The results were similar to those of the Hamburg wheel-tracking test; however, the cracking resistance was poor with a high recycled aggregate incorporation ratio. The dynamic modulus test results demonstrated excellent resistance to plastic deformation at a relatively high ratio of reclaimed aggregate admixture. The crack resistance was weakened when a high ratio of reclaimed aggregate mixture was used. CONCLUSIONS: As the reclaimed aggregate content increased, the plastic deformation resistance increased and the crack resistance decreased.

PURPOSES: This study evaluated the effect of fog seal treatment utilizing an agricultural oil-based asphalt concrete sealant (ABCS) on the long-term performance of an asphalt pavement. METHODS: Fog seal treatment using ABCS was applied on 800 m of the pavement section in the test section with a total length of 2,400 m; the remaining pavement section was not considered for this treatment. A series of laboratory and field tests were conducted on both sections, including a Marshall stability test, penetration test, viscosity test, skid resistance test, and pavement surface macrotexture test. In addition, the pavement condition index (PCI) was determined 8 years after the ABCS application to evaluate the effect of the ABCS treatment on the pavement’s long-term performance. RESULTS : The ABCS-treated section exhibited a PCI of 75, whereas the non-treated section exhibited a value of 64. Furthermore, a MicroPAVERTM‚ pavement management system determined that the pavement deterioration rates (i.e., drops in PCI) were 3.6 and 5.1 per year for the ABCS-treated and non-treated sections, respectively. CONCLUSIONS : The results of the series of laboratory and field tests revealed that the ABCS treatment increased the pavement performance life by approximately 3.5 years.

OBJECTIVES: The objective of this research is to develop additives for the modification of Solvent DeAsphalting Residue (SDAR) to be used as pavement materials, and evaluate the performance of asphalt mixture manufactured using the SDAR modified by developed additives. METHODS: The SDAR generally consists of more asphaltenes and less oil components compared to the conventional asphalt binder, and hence, the chemical/physical properties of SDAR are different from that of conventional asphalt binder. In this research, the additives are developed using the low molecular oil-based plasticizer to improve the properties of SDAR. First, the chemical property of two SDARs is analyzed using SARA (saturate, aromatic, resin, and asphaltene) method. The physical/rheological properties of SDARs and SDARs containing additives are also evaluated based on PG-grade method and dynamic shear-modulus master curve. Second, various laboratory tests are conducted for the asphalt mixture manufactured using the SDAR modified with additives. The laboratory tests conducted in this study include the mix design, compactibility analysis, indirect tensile test for moisture susceptibility, dynamic modulus test for rheological property, wheeltracking test for rutting performance, and direct tension fatigue test for cracking performance. RESULTS : The PG-grade of SDARs is higher than PG 76 in high temperature grades and immeasurable in low temperature grades. The dynamic shear modulus of SDARs is much higher than that of conventional asphalt, but the modified SDARs with additives show similar modulus compared to that of conventional asphalt. The moisture susceptibility of asphalt mixture with modified SDARs is good if, the antistripping agent is included. The performance (dynamic modulus, rutting resistance, and fatigue resistance) of asphalt mixture with modified SDARs is comparable to that of conventional asphalt mixture when appropriate amount of additives is added. CONCLUSIONS: The saturate component of SDARs is much less than that of conventional asphalt, and hence, it is too hard and brittle to be used as pavement materials. However, the modified SDARs with developed additives show comparable or better rheological/physical properties compared to that of conventional asphalt depending on the type of SDAR and the amount of additives used.

1960년대 이후 서울시는 급속히 산업화가 진행되면서 건물과 인공 포장된 도로가 급격히 증가하였으며 특히 서울시 불투수성 포장비율이 전체면적의 50% 수준에 달하며 불투수성 토양 포장도가 70% 이상인 지 역이 서울시 전체 면적의 48.2%를 차지하고 있다. 이로 인한 주요 문제로 지구온난화에 따른 기후변화로 도 심 집중강우가 빈번히 발생하여 도로침수, 포장체 파손 등이 발생하고 있다. 따라서 불투수성 포장도로를 개량하여 자연 물순환이 확보될 수 있도록 개선하는 연구가 진행되어오고 있다. 최근 서울시에서는 불투수 성 도로포장 증가와 이상기후에 따른 집중강우 등으로 새로운 도로포장의 필요성이 제기되고 있다. 이를 위 해 도심지 홍수발생시 하수관으로 직접 유입되는 우수량을 감소시켜 도로침수 억제를 기대함과 동시에 지하 수위 복원으로 도로침하 및 함몰 발생을 저감시켜 도심지의 지속적인 불투수면적 증가로 인한 지하수위 저 하 문제를 완화하여 도로침하 및 함몰 사고발생을 저감시키고자 2011년「투수 블록포장 설계, 시공 및 유지 관리 기준(Ver 1.0)」을 마련 ․ 시행하고 있다(도로관리과-112390호, 2011.8.31.). 서울시에서는 이러한 투수 블록에 대한 관리 기준에 있어 투수블록에 대한 투수성 지속성을 평가하기 위한 방안으로 자체투수블록에 대해 실내에서 인위적인 협착물을 통해 오염전후 투수계수를 측정, 등급을 산정하고 있으며 이러한 등급은 3종류의 투수계수 0.1mm/sec을 기준으로 5등급으로 구분되어 현장에 적용평가하고 있다. 그러나, 서울시에서 투수블록 포장 기준으로 활용하고 있는 투수 지속성 검증시험은 현장적용 전 등급 평가에만 활용되고 있으며 적용이후 이러한 사전 평가 등급이 어떻게 변화되는지에 대한 추적조사자료는 부족한 실정이므로 본 연구에서는 공용기간별 투수블록 투수 지속성 성능을 평가하여 투수블록의 공극막 힘 현상, 투수성능 변화 등 투수블록의 수명 예측자료를 확보하고자 연구를 시행하였다. 이러한 투수블록 투수성 수명예측자료를 통해 유지시점, 유지관리 방안을 도출하고 현장에 적용된 투수블 록의 기능을 초기상태로 유지하며 그 고유의 기능이 저하됨이 없이 유지될 수 있기 위한 방안을 검토하고자 하였다. 또한 실내 투수 성능 지속성 검증 시험과 현장투수 시험과의 상관성 분석을 통해 지속성 검증시험 의 효과를 분석하고 초기 평가된 지속성 검증시험 결과와 공용이후의 투수성능 상관성을 분석하였다.

일반국도의 연장 및 공용기간의 증가로 포장상태가 불량한 구간이 증가하고 이로 인한 유지보수비용이 급 격하고 있다. 제한된 예산으로 일반국도를 효율적으로 관리하기 위하여 포장관리시스템(PMS, Pavement Management System)이 1980년대 말 도입된 이후 현재 한국건설기술연구원에서 국토교통부로부터 위임을 받아 운영 중에 있다. 일반국도 PMS에는 다양한 종류의 유지보수 공법이 적용되고 있다. 1990년대 국내 아 스팔트 포장에서는 소성변형이 급격하게 증가하여 이를 억제하기 위하여 개질 아스팔트를 이용한 장수명 포 장 공법이 1990년대 중반부터 도입되기 시작하였다. 대표적인 장수명 아스팔트 포장 공법으로는 개질아스 팔트 포장(PMA, Polymer Modified Asphalt)과 SMA(Stone Mastic Asphalt)이 있다. 하지만 이러한 장수 명 포장은 일반 아스팔트 포장에 비하여 높은 단가와 현장 공용성 검증 부족으로 일반국도에 활발하게 적용 되고 있지 못하고 있는 실정이다. 따라서 본 연구에서는 일반국도 PMS 데이터베이스를 바탕으로 장수명 아 스팔트 포장의 공용성능을 평가하였다. 일반국도 PMS는 포장상태를 균열률과 소성변형량을 적용하고 있으므로 공용수명을 결정하는 공용성능 인자로 균열률과 소성변형량을 적용하였다. 그림 1은 내유동성 아스팔트 덧씌우기 포장 구간에서 공용기 간에 따른 균열률과 소성변형량의 변화를 나타낸다. 공용수명은 임계 균열률(15%)과 소성변형량(10mm) 을 기준으로 결정하였다. 마지막으로 다양한 조건에 적용된 장수명 아스팔트 포장의 공용수명 영향을 미 치는 인자, 예를 들어 교통량, 환산교통량, 기온 등에 대한 통계분석을 실시하였다. 장수명 아스팔트 포장 의 객관적인 공용성능을 평가하기 위하여 동일한 조건에서 적용된 일반 아스팔트 포장의 공용수명과의 비, 공용성능비를 제안하였다.

This paper describes an evaluation of the in-service structural performance of a glass fiber-reinforced polymer (GFRP) slab bridge. This first all-GFRP slab bridge was installed in Korea on May 2002. The GFRP slab bridge is a simply supported, its length is 10.0 m, and is designed to carry two-lane traffic and has an overall width of 8.0m. The GFRP slab bridge is a sandwich structure with a corrugated core, fabricated by hand lay-up process with E-glass fibers and vinyl ester resins. The assessment of in-service performance for the GFRP slab bridge in 2004, 2011 includes a field load testing identical to that performed in 2002. The assessment indicates that the GFRP slab bridge has no structural problems and is structurally performing well in-service as expected.

현재 도로분야에서 콘크리트 포장의 양적증가와 공용연수 증가로 콘크리트 포장의 손상에 따른 유지보수문제가 크게 부각되기 시작했다. 국내에서 적용되고 있는 콘크리트 포장 유지보수는 통상 손상된 부위의 부분보수후 아스팔트 덧씌우기 공법을 일괄적으로 적용하고 있다. 본 연구에서는 콘크리트 포장의 예방적 유지관리공법인 다이아몬드 그라인딩 공법에 대한 적용기준 평탄성, 미끄럼저항성, 소음, 경제성, 포장의 수명연장등 이론적인 연구를 수행하고, 이를 바탕으로 시험시공을 실시하여 초기공용성에 대한 측정을 실시하였다. 종단평탄성측정은 ARAN의 차륜부 좌우에 별도의 평탄성 측정센서를 부착 자동측정차량을 통해 시공전 후의 평탄성을 측정하였다. 미끄럼저항성은 SN기준값으로 분류하여 다이아몬드 그라인딩 시공전 후의 차로별 미끄럼 저항값을 측정하였다. 소음측정은 시공구간과 일반구간, 차종, 속도를 변수로 선정하여 소음발생정도를 측정하였고, 시공전 후의 평균조도깊이를 측정하여 다이아몬드 그라인딩 공법의 평가를 실시하였다. 분석결과 종단평탄성은 시공후 6%~40%가 향상되었으며, 미끄럼저항성은 1차로에서 66%, 2차로에서 37%의 증진효과가 있었다. 소음은 다이아몬드 그라인딩 구간에서 평균 3.4dB의 소음감소 효과가 나타났으며, 평균조도 깊이는 79%의 깊이 항상 효과를 보였다. 그러므로, 향후 기존 콘크리트 포장의 유지보수공법으로서 다이아몬드 그라인딩 공법의 국내적용이 적정하다고 판단된다.

To monitor static and dynamic responses of bridges, an image-based monitoring system using networking Pan-Tilt-Zoom IP (Internet Protocol) cameras has been developed. Verification testing is carried out during the human-excited vibration test of the stay cables in a cable-stayed bridge. As well as identifying the natural frequencies of the stay cable, the reasonable damping ratios are successfully extracted from the acquired images.

In this paper, internal and external research trends and plans related to development of performance–based evaluation methodology for structures in use was introduce to deal with the various problems due to the aging of the domestic SOC(Social Overhead Capital) facilities preemptively.

The aim of this study is to evaluate performance of wind-resistant for existing bridges. For this purpose, It is examined the necessity of dynamic wind tunnel test for existing bridge by theoretical equations before implementation of the test, and the method of wind-resistant performance evaluation is presented so that wind tunnel test would be determined whether it needs to conduct.