간행물

한국도로학회논문집 KCI 등재 International journal of highway engineering

권호리스트/논문검색
이 간행물 논문 검색

권호

제18권 제2호 (2016년 4월) 12

1.
2016.04 구독 인증기관 무료, 개인회원 유료
PURPOSES : The performance properties (indirect tensile strength, rutting resistance, and resilient modulus) of recycled aged CRM mixtures and their correlation with Superpave binder properties (viscosity, high failure temperature, G*sinδ, and stiffness) were investigated. METHODS: A series of Superpave binder tests was performed by using a rotational viscometer, DSR, and BBR to evaluate the performance properties. In addition, the CRM mixes were artificially aged through accelerated aging processes, and their properties were evaluated. The correlation between the properties of recycled aged CRM binders and the engineering properties of recycled aged CRM mixtures was experimentally determined. RESULTS : The rut depth values decreased and the ITS values increased with increasing high failure temperature. In general, the resilient modulus properties seemed to be poorly correlated with the high-temperature values, regardless of the aggregate source. CONCLUSIONS: The recycled aged CRM binders and mixtures can lead to satisfactory performance, and the properties of these binders are strongly correlated with the engineering properties of the mixtures.
4,000원
2.
2016.04 구독 인증기관 무료, 개인회원 유료
PURPOSES: This paper investigates behavior and performance of concrete pavement in tunnel based on temperature data from field. METHODS : In this study, there are 4 contents to evaluate concrete pavement in tunnel, First, Comparison for distress was conducted at outside, transition, and inside part of tunnel. Secondly, temperature data was collected in air and inside concrete pavement in outside and inside tunnel. Thirdly, FEM analysis was performed to evaluate stress condition, based on temperature data from field. Finally, performance prediction was done with KPRP program. RESULTS: From the distress evaluation, failure of inside tunnel was much less than it of outside tunnel, Temperature change in tunnel was less than out side, and also it was more stable. According to result of FEM analysis, both curling stress status of inside tunnel was lower than it of outside tunnel. Based on KPRP program analysis, performance of inside tunnel was longer than outside. CONCLUSIONS : Through all study about behavior and performance of concrete pavement in tunnel, condition in tunnel has more advantages from environmental and distress point of view. Therefore, performance of inside tunnel was better than outside.
4,000원
3.
2016.04 구독 인증기관 무료, 개인회원 유료
PURPOSES: The behavior of a concrete pavement in a tunnel was investigated, based on temperature data obtained from the field and FEM analysis. METHODS: The concrete pavement in a tunnel was evaluated via two methods. First, temperature data was collected in air and inside the concrete pavement both outside and inside the tunnel. Second, FEM analysis was used to evaluate the stress condition associated with the slab thickness, joint spacing, dowel, and rock foundation, based on temperature data from the field. RESULTS : Temperature monitoring revealed that the temperature change in the tunnel was lower and more stable than that outside the tunnel. Furthermore, the temperature difference between the top and bottom of the slab was lower inside the tunnel than outside. FEM analysis showed that, in many cases, the stress in the concrete pavement in the tunnel was lower than that outside the tunnel. CONCLUSIONS : Temperature monitoring and the behavior of the concrete pavement in the tunnel revealed that, from an environmental point of view, the condition in the tunnel is advantageous to that outside the tunnel. The behavior in the tunnel was significantly less extreme, and therefore the concrete pavement in the tunnel could be designed more economically, than that outside the tunnel.
4,000원
4.
2016.04 구독 인증기관 무료, 개인회원 유료
PURPOSES: The objective of this study is to determine the milling temperature that minimizes the binder-induced damage to the aggregate; this is achieved by evaluating the temperature dependence of the viscosity of the asphalt binder, with the aim of developing an effective heating process for warm in-place recycling. METHODS : The validity of the indoor test was confirmed by conducting an internal heating test based on the on-site heating test. In addition, the adhesive power of the binder was measured at various temperatures (30℃, 40℃, 50℃, 60℃, 70℃) via three types of measuring methods. RESULTS: The surface temperature spectrum of field test was slight different with that of laboratory test. But, the spectra of inner temperature between the field and the laboratory was almost similar. Also, the adhesion of the asphalt binder was measured from 30℃ to 70℃. The adhesion of the binder was significantly decreased from 60℃. Contrary to other temperature, the adhesion was slightly changed from 60℃ to 70℃. Also the inner temperature between two different heating methods was shown similar temperature spectra. CONCLUSIONS: The pavement heating temperature spectrum of hot in place recycling method was simulated by a laboratory test. Based on this study, the optimum temperature was 60℃~70℃ for reducing aggregate damage during milling process. The susceptibility heating method developed in this study can be maintained the optimum inner temperature range.
4,000원
5.
2016.04 구독 인증기관 무료, 개인회원 유료
PURPOSES : The objective of this study is to determine the optimal frequency of ground penetrating radar (GPR) testing for detecting the voids under the pavement. METHODS : In order to determine the optimal frequency of GPR testing for void detection, a full-scale test section was constructed to simulate the actual size of voids under the pavement. Voids of various sizes were created by inserting styrofoam at varying depths under the pavement. Subsequently, 250-, 500-, and 800-MHz ground-coupled GPR testing was conducted in the test section and the resulting GPR signals were recorded. The change in the amplitude of these signals was evaluated by varying the GPR frequency, void size, and void depth. The optimum frequency was determined from the amplitude of the signals. RESULTS: The capacity of GPR to detect voids under the pavement was evaluated by using three different ground-coupled GPR frequencies. In the case of the B-scan GPR data, a parabolic shape occurred in the vicinity of the voids. The maximum GPR amplitude in the A-scan data was used to quantitatively determine the void-detection capacity. CONCLUSIONS: The 250-MHz GPR testing enabled the detection of 10 out of 12 simulated voids, whereas the 500-MHz testing allowed the detection of only five. Furthermore, the amplitude of GPR detection associated with 250-MHz testing is significantly higher than that of 500-MHz testing. This indicates that 250-MHz GPR testing is well-suited for the detection of voids located at depths ranging from 0.5~2.0 m. Testing at frequencies lower than 250 MHz is recommended for void detection at depths greater than 2 m.
4,000원
6.
2016.04 구독 인증기관 무료, 개인회원 유료
PURPOSES : The field application and performance of continuously reinforced concrete pavement (CRCP), constructed by using the mechanical tube-feeding method, are evaluated in this study. METHODS: The location of the rebar was evaluated by using the MIRA system. The early-age CRCP performance was evaluated via visual survey, in which the crack spacing and crack width were examined. RESULTS: The location of longitudinal reinforcing bars was evaluated via MIRA testing and the results showed that the longitudinal rebars all lie within a given tolerance limit (±2.5 cm) of the target elevation. In addition, owing to the low temperature when the concrete was pured, the crack spacing in the Dae-Gu direction is slightly wider than that of the Gwang-Ju direction. Almost all of the crack spacings lay within the range of 1.0 m~3.0 m. A crack width of <0.3 mm was measured at the pavement surface. However, as revealed by the field survey, the crack spacing was not correlated with the crack width. CONCLUSIONS : In CRCP constructed by using the mechanical tube-feeding method, almost all of the longitudinal reinforcing bars lay within the tolerance limit (2.5 cm) of the target elevation. The concrete-placing temperature affects the crack spacing, owing to variations in the zero-stress temperature. Crack survey results show that there is no correlation between the crack spacing and crack width in CRCP.
4,000원
7.
2016.04 구독 인증기관 무료, 개인회원 유료
PURPOSES : The applicability of the mechanics-based similarity concept (suggested by Feng et al.) for determining scaled variables, including length and load, via laboratory-scale tests and discrete element analysis, was evaluated. METHODS: Several studies on the similarity concept were reviewed. The exact scaling approach, a similarity concept described by Feng, was applied in order to determine an analytical solution of a free-falling ball. This solution can be considered one of the simplest conditions for discrete element analysis. RESULTS : The results revealed that 1) the exact scaling approach can be used to determine the scale of variables in laboratory tests and numerical analysis, 2) applying only a scale factor, via the exact scaling approach, is inadequate for the error-free replacement of small particles by large ones during discrete element analysis, 3) the level of continuity of flowable materials such as SCC and cement mortar seems to be an important criterion for evaluating the applicability of the similarity concept, and 4) additional conditions, such as the kinetics of particle, contact model, and geometry, must be taken into consideration to achieve the maximum radius of replacement particles during discrete element analysis. CONCLUSIONS : The concept of similarity is a convenient tool to evaluate the correspondence of scaled laboratory test or numerical analysis to physical condition. However, to achieve excellent correspondence, additional factors, such as the kinetics of particles, contact model, and geometry, must be taken into consideration.
4,000원
8.
2016.04 구독 인증기관 무료, 개인회원 유료
PURPOSES: The objective of this study was to determine the optimum ratio of mix design, for a reclaimed asphalt pavement (RAP) content of 100%, for spray injection application. METHODS: A literature review revealed that spray injection is an efficient and cost-effective application for fixing small defective regions of an asphalt pavement. Rapid-setting polymer-modified asphalt mixtures prepared from two types of rapid-setting polymer asphalt emulsion were subjected to Marshall stability and wet track abrasion tests, in order to identify the optimum mix designs. RESULTS and CONCLUSIONS : Different mix designs of type A and type B emulsions were prepared using RAP and virgin aggregates, in order to compare the performance and determine the optimum mix design. The performance of mixtures prepared with RAP was superior to that of mixtures containing virgin aggregates. Moreover, for optimum ratio of the design, the binder content prepared from RAP was set to 1~2% lower than that consisting of virgin aggregates. Compared to their Type A counterparts, type B mixtures consisting of a reactive emulsion performed better in the Marshall stability and wet track abrasion tests. The initial results confirmed the advantages associated with using RAP for spray injection applications. Further studies will be performed to verify the difference in the optimum mix design and performance obtained in the lab-scale test and tests conducted at the job site by using the spray injection machine.
4,200원
9.
2016.04 구독 인증기관 무료, 개인회원 유료
PURPOSES: The national highways and expressways in Korea constitute a total length of 17,951 km. Of this total length of pavement, the asphalt pavement has significantly deteriorated, having been in service for over 10 years. Currently, hot in-place recycling (HIR) is used as the rehabilitation method for the distressed asphalt pavement. The deteriorated pavement becomes over-heated, however, owing to uncontrolled heating capacity during the pre-heating process of HIR in the field. METHODS: In order to determine the appropriate heating method and capacity of the pre-heater at the HIR process, the heating temperature of asphalt pavement is numerically simulated with the finite element software ABAQUS. Furthermore, the heating transfer effects are simulated in order to determine the inner temperature as a function of the heating system (IR and wire). This temperature is ascertained at 300 ℃, 400℃, 500℃, 600℃, 700°℃, and 800℃ from a slab asphalt specimen prepared in the laboratory. The inner temperature of this specimen is measured at the surface and five different depths (1 cm, 2 cm, 3 cm, 4 cm, and 5 cm) by using a data logger. RESULTS: The numerical simulation results of the asphalt pavement heating temperature indicate that this temperature is extremely sensitive to increases in the heating temperature. Moreover, after 10 min of heating, the pavement temperature is 36%~38% and 8%~10% of the target temperature at depths of 25 mm and 50 mm, respectively, from the surface. Therefore, in order to achieve the target temperature at a depth of 50 mm in the slab asphalt specimen, greater heating is required of the IR system compared to that of the gas. CONCLUSIONS : Numerical simulation, via the finite element method, can be readily used to analyze the appropriate heating method and theoretical basis of the HIR method. The IR system would provide the best heating method and capacity of HIR heating processes in the field.
4,000원
10.
2016.04 구독 인증기관 무료, 개인회원 유료
PURPOSES : Nowadays, cavity phenomena occur increasingly in pavement layers of downtown areas. This leads to an increment in the number of potholes, sinkholes, and other failure on the road. A loss of earth and sand from the pavement plays a key role in the occurrence of cavities, and, hence, a structural-performance evaluation of the pavement is essential. METHODS: The structural performance was evaluated via finite-element analysis using KPRP and KICTPAVE. KPRP was developed in order to formulate a Korean pavement design guide, which is based on a mechanical-empirical pavement design guide (M-EPDG). RESULTS: Installation of the anti-freezing layer yielded a fatigue crack, permanent deformation, and international roughness index (IRI) of 13%, 0.7 cm, and 3.0 m/km, respectively, as determined from the performance analysis conducted via KPRP. These values satisfy the design standards (fatigue crack: 20%, permanent deformation: 1.3 cm, IRI: 3.5 m/km). The results of FEM, using KICTPAVE, are shown in Figures 8~12 and Tables 3~5. CONCLUSIONS: The results of the performance analysis (conducted via KPRP) satisfy the design standards, even if the thickness of the anti-freezing layer is not considered. The corresponding values (i.e., 13%, 0.7 cm, and 3.0 m/km) are obtained for all conditions under which this layer is applied. Furthermore, the stress and strain on the interlayer between the sub-grade and the anti-freezing layer decrease gradually with increasing thickness of the anti-freezing layer. In contrast, the strain on the interlayer between the sub-base and the anti-freezing layer increases gradually with this increase in thickness.
4,000원
11.
2016.04 구독 인증기관 무료, 개인회원 유료
PURPOSES : The aim of this study was to compare the performance of the QUEENSOD method and the gravity model in estimating Origin-Destination (O/D) tables for a large-sized microscopic traffic simulation network. METHODS : In this study, an expressway network was simulated using the microscopic traffic simulation model, VISSIM. The gravity model and QUEENSOD method were used to estimate the O/D pairs between internal and between external zones. RESULTS: After obtaining estimations of the O/D table by using both the gravity model and the QUEENSOD method, the value of the root mean square error (RMSE) for O/D pairs between internal zones were compared. For the gravity model and the QUEENSOD method, the RMSE obtained were 386.0 and 241.2, respectively. The O/D tables estimated using both methods were then entered into the VISSIM networks and calibrated with measured travel time. The resulting estimated travel times were then compared. For the gravity model and the QUEENSOD method, the estimated travel times showed 1.16% and 0.45% deviation from the surveyed travel time, respectively. CONCLUSIONS : In building a large-sized microscopic traffic simulation network, an O/D matrix is essential in order to produce reliable analysis results. When link counts from diverse ITS facilities are available, the QUEENSOD method outperforms the gravity model.
4,200원
12.
2016.04 구독 인증기관 무료, 개인회원 유료
PURPOSES: In this paper, the effectiveness of speed-maintained standardization in road geometry on environmental impact at a downward slope location, based on greenhouse gas (GHG) emission indicators, was studied. Specifically, the aim of this study was to ascertain whether speed-maintained standardization resulted in decreased CO2 emissions as well as noise pollution, due to reduced vehicle speeds. METHODS : In this study, speed-maintained standardization in road geometry was proposed as a means to reduce vehicle speeds, with a view to reducing CO2 emissions and noise pollution. This technique was applied at a downward slope location. The vehicle speeds, CO2 emissions, and noise levels before and after application of speed-maintained standardization were compared. RESULTS: It was found that speed-maintained standardization was effective as a means to reduce speed, as well as CO2 emissions and noise pollution. By applying speed-maintained standardization, it was confirmed that vehicle speeds were reduced consistently. As a result, CO2 emissions and noise levels were decreased by 9% and 11%, respectively. CONCLUSIONS : This study confirmed that speed-maintained standardization in road geometry is effective in reducing vehicle speeds, CO2 emissions, and noise levels. Moreover, there is further scope for the application of this method in the design of roads in urban and rural areas, as well as in the design of highways.
4,000원