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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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International Journal of Highway Engineering
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Journal DOI :
Korean Society of Road Engineers
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Volume & Issues
Volume 10, Issue 4 - Dec 2008
Volume 10, Issue 3 - Sep 2008
Volume 10, Issue 2 - Jun 2008
Volume 10, Issue 1 - Mar 2008
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Modifications of RC/TS(Resonant Column and Torsional Shear) Device for the Large Strain
Bae, Yoon-Shin ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 1~10
Conventional RC/TS(resonant column and torsional shear) device usesa specimen with an aspect ratio(height-to-diameter) of 2:1 and this generates a maximum shear strain in the sample of about 1.5% at the maximum rotation of the drives system. The objective of this study is to modify RC/TS device to generate higher strain amplitude. The modifications include a new base pedestal to overcome the limitations in the travel of the drive system and modification of coil wiring to increase torque. The effects of the new coil wire on torque in the electro magnetic drive system were evaluated and the application of modified device was illustrated using sand soil.
Evaluation of Correlation between Aggregate Gradation and Dynamic Modulus with Statistical Analysis
Lee, Kwan-Ho ; Cho, Kyung-Rae ; Lee, Byung-Sik ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 11~18
In recent, lots of researches for mechanical-empirical design concept for asphalt pavement are on going. AASHTO 2002 Design Guide in USA and KPRP(Korean Pavement Research Program) in Korea are under developing. In these programs, the mechanical properties of hot mix asphalt are a key role for design and analysis. Unfortunately, there is no proper database on the mechanical properties of hot mix asphalt, such as dynamic modulus. The use of dynamic modulus has couple of good advantages which is based on temperature, traffic loading and frequency on pavement. In this research, the verification of the relationship between maximum nominal aggregate size and dynamic modulus has been carried out. Also, test specimen size effect on dynamic modulus has been conducted. Considering the limitation of laboratory testing machine in Korea, test specimen with 100mm diameter and 150mm height is recommended for dynamic modulus test. Also, as the maximum nominal aggregate size increases, the dynamic modulus of hot mix asphalt increases.
Development of a Real Time Video Image Processing System for Vehicle Tracking
Oh, Ju-Taek ; Min, Joon-Young ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 19~31
Video image processing systems(VIPS) offer numerous benefits to transportation models and applications, due to their ability to monitor traffic in real time. VIPS based on wide-area detection, i.e., multi-lane surveillance algorithm provide traffic parameters with single camera such as flow and velocity, as well as occupancy and density. However, most current commercial VIPS utilize a tripwire detection algorithm that examines image intensity changes in the detection regions to indicate vehicle presence and passage, i.e., they do not identify individual vehicles as unique targets. If VIPS are developed to track individual vehicles and thus trace vehicle trajectories, many existing transportation models will benefit from more detailed information of individual vehicles. Furthermore, additional information obtained from the vehicle trajectories will improve incident detection by identifying lane change maneuvers and acceleration/deceleration patterns. The objective of this research was to relate traffic safety to VIPS tracking and this paper has developed a computer vision system of monitoring individual vehicle trajectories based on image processing, and offer the detailed information, for example, volumes, speed, and occupancy rate as well as traffic information via tripwire image detectors. Also the developed system has been verified by comparing with commercial VIP detectors.
An Analysis of Effectiveness of Geometric Improvement on Horizontal Curves in Two-Lane Highway
Shim, Kywan-Bho ; Choi, Jai-Sung ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 33~46
A two-lane highway has a high rate of head-on collisions, sideswipe collisions, crashes with an fixed object. This study was to analyze the weakness of a cross section and a horizontal curve in a two-lane highway and find countermeasures to improve the traffic operations and safety. This study evaluated the effectiveness of widening, curve flattening and superelevation, verified it with a case study and assessed the economical efficiency. This study selected the difference between tangent section operating speeds and curve section operating speeds as an evaluation index of horizontal curve section in a two-lane highway. The results indicated that curve flattening is the best way to improve the traffic safety in a two-lane highway. This study has implication that it provides the quantitative effects of curve flattening. Also directions for future study were discussed.
Development of Severity Model for Rural Unsignalized Intersection Crashes
Lee, Dong-Min ; Kim, Eung-Cheol ; Sung, Nak-Moon ; Kim, Do-Hoon ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 47~56
Generally, accident exposure at intersections is relatively higher than that at roadway segments due to more possibility of merging, diverging, turning, crossing, and weaving maneuver. Furthermore, the traffic accident rate at intersections has been rapidly increasing since 1990's. Since there is more opportunity of conflict at unsignalized intersection, frequency and severity of traffic accident are more severe than signalized intersections. The purpose of the study is to analyze factors causing vehicle crashes and provide intersection design guidelines to improve intersection safety. For this study, vehicle to vehicle crash data of 116 rural 3 legs unsignalized were collected and field surveys were conducted for traffic and geometric conditions. Ordered probit models were developed to analyze the severity of crashes. It was found that weather, obstacles in minor roadsides, presence of major exclusive right lane, presence of major road crosswalk, difference between posted speed of major road and minor road, land-use around intersections, shoulder width of major road, ADT of major road are significant factors for intersection safety.
Strength and Deformation Characteristics on Stabilized Pavement Geomaterials(I): Laboratory Test
Park, Seong-Wan ; Ji, Jong-Keun ; Park, Hee-Mun ; Ohm, Byung-Sik ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 57~68
The stabilization techniques in the pavement foundations have advantages in increasing pavement performance and reducing pavement thickness. By mixing the geomaterials and stabilizer, the economical and structurally sound layer can be added in the pavement system. Until now, these techniques have been applied in the field empirically and the design criteria for stabilization has not been established. The purposes of this paper are to evaluate the mechanistic properties of stabilizers used for geomaterials and determine the type and optimum amount of stabilizer for each technique. The unconfined compressive testing and repeated load resilient modulus test were conducted on the coarse grained soils mixed with various types of stabilizer to investigate the strength and deformation characteristics of stabilized geomaterials. It is found from the test that the unconfined compressive strength of stabilized geomaterials is more than ten times higher than that of gradation modified geomaterials. The resilient modulus of stabilized geomaterials increases by
times compared to the original soils and tends to increase with increase of volumetric and deviatoric stress, and amount of stabilizer.
An Analysis of Influencing Factors to Pedestrian Quality of Service by Utilizing Analytic Hierarchy Process
Kim, Tae-Ho ; Jin, Jang-Won ; Bae, Gi-Mok ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 69~77
This article proposes new method for estimating pedestrian quality of service(QOS) that is useful to changing pedestrian environment by examining pedestrian quality of service as well as developing new method that integrate qualitative variables into the estimating indicators for the pedestrian movement right. Based on survey questionnaire addressed to experts group, the obtained data for the indicators were analyzed through Analytic Hierarchy Process(AHP). The results show that pedestrian traffic flow(quantitative figure: 52%), sidewalk geometric(quantitative figure: 16%), sidewalk usage behavior(qualitative figure: 11%) in commercial and business zone pointed out the importance of quantitative indicators such as pedestrian traffic flow, and sidewalk geometric. In addition, the results also show that pedestrian traffic flow(quantitative figure: 30%), sidewalk geometric(quantitative figure : 22%), sidewalk usage behavior(qualitative figure: 20%) indicate the significance of qualitative indicators such as pedestrian's sidewalk usage.
Determining the Appropriate Installation Angle of Skewed Sensor to Measure Vehicle Wandering
Oh, Ju-Sam ; Jang, Kyung-Chan ; Kim, Min-Sung ; Jang, Jin-Hwan ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 79~86
This paper proposed the appropriate installation angle of skewed sensors for measuring vehicle wandering data, which are collected to figure out the location of dynamic weight of a moving vehicle on roadways. We developed a device using tape-switch sensors and a computer program and collected vehicle wandering data with the device and probe vehicles. As a result, the steeper the skewed sensor was installed, the lower the error was shown. However, we could not collect proper data when a skewed sensor was set up higher than
due to tandem axle. Therefore, this study suggested the appropriate angle of skewed sensors as a degree of
for gathering wandering data.
Characteristic of Vehicle Lateral Displacements on National Highways
Oh, Ju-Sam ; Cho, Yoon-Ho ; Kim, Hyoung-Soo ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 87~96
Wandering, variation of wheel tracks, has not been considered as an important factor for pavement designs and maintenance due to measuring difficulties. In order to investigate vehicle lateral displacements on roadways, this study measured wheel tracks on two-lane and four-lane National highways with lane widths 3.25m and 3.5m. The results showed that the tracks of left and right wheels were distributed into different forms, and those of left wheels were more concentrated. In the mean of the left distributions, 59.5cm and 80.7cm were obtained on lane widths 3.25m and 3.5m respectively by cars, and 58.4cm and 73.6cm were obtained by trucks. These mean differences seem to be generated from those between the lane widths. It is recommended to apply the distribution of left wheel tracks for pavement designs.
A Development of Design Method for Deceleration Transition Curve Based on Vehicle Driving Characteristics
Lee, Jeom-Ho ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 97~107
I study for design criteria and research about Interchange diverging area of express highway and freeway, the most recent, at interchange diversion of express highway and freeway, design criteria and researches are focus on safety guarantee a point of view movement dynamics of vehicle and road geometric as to transition section, deceleration section, curve radius, nose section, outflow angle etc, that is, design criteria and research of Interchange diverging area have not consider a point of view movement dynamics of vehicle and road geometric and driver, so that I will be focus characteristic of runing speed on trasion curve. and I will consider vehicle running speed characteristics and study problem of Interchange diverging area design criteria. For this study, First, analysis meaning about theory of now design criteria, Second, look at vehicle running speed and traffic accident characteristics of Interchange diverging area, Third, propose new deceleration transition curve design method get along vehicle running speed characteristics of Interchange diverging area. new deceleration transition curve design method put out new outcoums, that is, I definite cause to safety new deceleration transition curve design method better than pressently, used design criteria of Interchange diverging area, especially, deceleration transition curve design criteria produced good result in the running speed 50km/h, 40km/h, that is inertia better than inertia of present used design criteria. and deceleration transition curve is extended better than present transition curve criteria, so that new deceleration transition curve design method safety is good better than the past method safety.
A Study on the Stability of Embankment Due to the Construction of Embankment Combined Use Road
Kim, Sung-Nam ; Lee, Young-Woo ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 109~118
This study analyzes the change of stability of embankment due to the construction of embankment combined used road with two different construction phases. The stabilities have been checked both in the phase of earth banking for a road construction and in the phase of the application of the traffic roads(DB-24). In both cases the factor of safety has been found higher than 1.3 which is the general criterion of the safety of an embankment. The results indicate that the safety of an embankment due to the construction of embankment combined use road is assured, and thus, it is thought that the construction of embankment combined use road can be considered for cutting down on expenses of construction sites for a road construction. However, the pre-examination of stability due to the construction should be carried out because it decreases the factor of safety of an embankment. From this study, it has been found that the factor of safety was dropped most when the water level rose in the transient flow. The result indicates that the stability analysis of a river embankment where the water level changes frequently should be carried out in the condition of transient flow. It is recommended that the inner side of an embankment should have a slope of 1:2 which is identical with the slope of the existing embankment. In addition, the factor of safety also can be decreased due to the traffic loads, and therefore, the effect should also be considered after the construction of embankment combined used road limiting the traffic loads.
The Evaluation of Existing Congestion Indices' Applicability for Development of Traffic Condition Index
Lee, Seung-Jun ; Kim, Tae-Young ; Ko, Han-Geom ; Bok, Ki-Chan ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 119~128
On the many highways, severe traffic congestions happen chronically and make traffic problems like reduction of mobility because of rapid increase of vehicles though road construction has been last. In order to solve these traffic problems, it is needed to find the trend and the symptom of traffic congestion and to analyze the cause of congestion and the(spatial) range affected by congestion. To develop the traffic condition monitoring index prior to doing all those things is most important. With this reason, many countries including U.S. had been developed the congestion criteria and indices. In this paper, applicability and characteristics of existing traffic congestion indices were considered and the direction for development of a new traffic condition index was suggested to achieve an effective traffic management.
Calculation Of Critical Stress On Jointed Concrete Pavement By Using Neural Networks & Linear Regression Models
Kang, Tae-Wook ; Ryu, Sung-Woo ; Kim, Seong-Min ; Cho, Yoon-Ho ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 129~138
The finite element method(FEM) was one of tools used to solve problem of previous Concrete Pavement and was applied to Korea Pavement Research Program Study. This study used the ABAQUS and the fortran analysis program to calculate the critical stress on jointed concrete pavement and compared and analyzed the results by using neural networks and linear regression model. In that case, which are not enough analysises by using FEM programs though many input variables, when the results of FEM with NN and linear regression models are compared, there are some differences. The other cases, which are reduced input variables and a lot of analysises each of them, results of Neural Networks(NN) and linear regression models are simulated to them of FEM. But, the result of NN is more exact than them of linear regression at the (0,0), (1,1). On the results of this study, it is suggested that the calculation of stress using NN is more compatible to Korea Pavement Research Program Study.
Change in Road Traffic Demand after the Operation of Exclusive Median Bus Lane in Seoul
Yoon, Byoung-Jo ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 139~147
8 Exclusive Median Bus Lanes(EMBL) are operated in Seoul metropolitan city after the opening of Chon-ho section in 1996. But the changes in the road traffic demand on the direct and indirect influence area have not reported. In this paper, before and after survey and analysis of road traffic demand on 3 EMBLs opened in 2004 are conducted. In summary, the traffic demand of 3 EMBL road section decreased dramatically to 24.7% after the opening and then increased 1.4% after a year. The traffic demand of detour road decreased to 2.9% after the opening and then increased 0.3% after a year. Considering measurement error as
, Road traffic demands on the influence area of EMBL section are a stable state after one year. So it is presumed that the trip demand on EMBL section using vehicle does not make a detour around the influence area but divert into another transport modal.
Evaluation of Deicing Performance and Effects of Deicers of the Winter Season
Doh, Young-Soo ; Lee, Byeong-Duck ; Choi, Kwang-Soo ; Kim, Kwang-Woo ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 149~158
This study was estimated on performance of deicers, corrosion inhibitors and low corrodible deicer used for removal of snow or ice on the road and on influence on structure. The weight loss rate after freezing and thawing of low corrodible deicer is lower than one of deicer, corrosion inhibitors and these combination. Relative dynamic elastic modulus of all except water, low corrodible deicer and NaCl+JF-1004 was radically reduced after freezing and thawing 150 cycles. And concretes after freezing and thawing were showed severe surface damage. It was found that individual use of low corrodible deicer and corrosion inhibitors had a problem of field application because of lack of early ice melting effect and considerably low durability. Products combined with NaCl was showed rapid weight loss by metal corrosion. Therefore, It will need to circumspectly select combination of deicers having low effect on concrete pavement and bridge if possible.
A New Approach for Incorporating Transportation User Perception into Transportation Engineering
Lee, Dong-Min ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 159~169
As users constitute one of the three components of a transportation system; and in many respects the most important component, user perception is a critical element within the concept of transportation services as transportation exists to provide high quality service to various user groups. However, this user perception has not been studied because it is difficult to be analyzed. The purpose of this study is to introduce the importance and alternative method to consider transportation user perception for various transportation engineering areas such as service quality and safety level of transportation system. For this purpose, various studies related to transportation user perception were reviewed. In addition, experiment results were analyzed to investigate the characteristics of transportation user perception.
Estimating Concrete Compressive Strength Using Shear Wave Velocity
An, Ji-Hwan ; Nam, Jeong-Hee ; Kwon, Soo-Ahn ; Joh, Sung-Ho ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 171~178
Compressive strength of concrete has been regarded as a very important parameter of the quality control both in new and existing concrete pavement. It has been used a lot as the concrete strength evaluation both in the various-mixture-using laboratory and construction field using the same mixture. An error usually occurs in the test experiments of the strength, even in the test experiments with evenly mixed and compacted specimens of the compressive strength. It is caused by the 'manually operated' compressing testing, or by the specimens preparation with eccentricity. When compressive strength of evenly mixed concrete is investigated by the curing ages at the construction field, there have to be lots of specimens. And it needs much labor and cost. To substitute the endlessly repeated test experiments of compressive strength, presumption of compressive strength, by nondestructive tests, is needed. In this study, elastic waves were used among various nondestructive tests. Compressive strength of concrete was presumed according to the curing ages, by using the shear wave velocity which is not affected by restricted conditions. In the result, shear wave velocity is very closely related to the compressive strength at the evenly mixed concrete.
Methodologies to Develop Payment Adjustment Regulations for Quality Control and Assurance of Concrete Pavements
Kim, Seong-Min ; Rhee, Suk-Keun ; Seo, Bong-Kyo ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 179~188
This study was performed as part of the development of the payment adjustment regulations for ensuring high performance of concrete pavements. The objectives of this study were to develop the reasonable quality measurement approaches for the implementation of the payment adjustment regulations and to propose the methods to determine the quality dependent pay factors. First, by using the statistics the slab thickness measurement data was analyzed and the methods to determine the allowable measurement errors, the proper measurement spacing, and the selection of the measurement location were proposed. In addition, to suggest the reasonable methods to determine the pay factors, by using the data of the slab thickness and concrete flexural strength, the pay factors based on the PWL(Percent Within Limits) method used in the USA were compared with those obtained considering the normal probability distribution and t distribution. Finally, the most appropriate method to determine the pay factors was proposed.
The Study of the Roughness of the Pavement on the Bridge Deck and Approach Slab using a 5year(2003 to 2007) Pavement Condition Survey Data
Park, Sang-Wook ; Suh, Young-Chan ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 189~197
Using a 5 year(2003 to 2007) pavement condition survey data from the highway pavement management system(HPMS), the roughness of the bridge deck pavement was analyzed. Based on the result of this analysis, this study tried to identify the factors affecting the deterioration of the bridge deck pavement condition. The data from HPMS indicates that the roughness of the bridge deck pavement is worse than that of the general pavement on the roadbed. The worse roughness of the bridge deck pavement is caused by the settlement of approach slab as well as the surface distress on the bridge deck pavement. In order to improve effectively the roughness of the bridge deck pavement, a management system was established in which not only the regular automated pavement condition survey to check the distress of surface of the bridge deck pavement was adopted but an automated surface profiler to check the degree of settlement of approach slab was applied.
Development of Prediction Method for Highway Pavement Condition
Park, Sang-Wook ; Suh, Young-Chan ; Chung, Chul-Gi ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 199~208
Prediction the performance of pavement provides proper information to an agency on decision-making process; especially evaluating the pavement performance and prioritizing the work plan. To date, there are a number of approaches to predict the future deterioration of pavements. However, there are some limitation to proper prediction of the pavement service life. In this paper, pavement performance model and pavement condition prediction model are developed in order to improve pavement condition prediction method. The prediction model of pavement condition through the regression analysis of real pavement condition is based on the probability distribution of pavement condition, which set to 5%, 15%, 25% and 50%, by condition of the pavement and traffic volume. The pavement prediction model presented from the behavior of individual pavement condition which are set to 5%, 15%, 25% and 50% of probability distribution. The performance of the prediction model is evaluated from analyzing the average, standard deviation of HPCI, and the percentage of HPCI which is lower than 3.0 of comparable section. In this paper, we will suggest the more rational method to determine the future pavement conditions, including the probabilistic duration and deterministic modeling methods regarding the impact of traffic volume, age, and the type of the pavement.
Effect of Underlying Layer Modeling on Curling Behavior of Concrete Slabs on Grade under Environmental Loads
Kim, Seong-Min ; Shim, Jae-Soo ; Yoon, Dong-Joo ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 209~220
This paper presents the differences in the analysis results according to the underlying layer modeling methods when analyzing the curling behaviors of the concrete slabs on grade under environmental loads. The models of the slab on grade system considered in this study included a three-dimensional(3D) model, a model composed of 3D slab and springs for underlying layers, and a model composed of 2D slab and springs for underlying layers. First, when the underlying layer consisted of one layer, the curling behaviors according to the different models were compared. Then, the underlying layers that consisted of two different materials and thicknesses were considered. The results of this study showed that the tensionless spring model for the underlying layer gave very accurate results when the underlying layer consisted of one layer. However, when the underlying layers consisted of two layers, the spring model for the underlying layers could overestimate the displacements and underestimate the maximum stress with a large elastic modulus of upper underlying layer, a small elastic modulus of under underlying layer, and thick underlying layers.
Development of Pavement Condition Index for the Municipal Pavements
Moon, Hyung-Chul ; Suh, Young-Chan ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 221~230
In Korea, Expressway and National Highway System has been continually managed by their own pavement management system. The pavement condition evaluation system has not been developed for the municipal roads except for Seoul city. Therefore, this study focuses on analyzing the characteristics of distress in major city's pavement and developing the pavement condition index for the municipal PMS. Panel rating and pavement condition survey for the selected pavement sections were conducted for developing pavement condition index. Municipal level pavement condition index(MPCI) was developed by statistical analysis. Also, a sensitivity analysis for each independent variable of the MPCI and comparison with other pavement condition indicies, such as SPI and HPCI, were performed.
System Development and Field Application for Measuring installation Interval and Height of Road safety Facilities Using a tine Scanning Camera
Moon, Hyung-Chul ; Suh, Young-Chan ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 231~237
One of the basic requirements for the most advanced countries would be the well-planned traffic infrastructures. For such traffic safety systems, foreign countries follow the current tendency to which they manage the traffic facilities and equipments based on the objective assessment for the state of every traffic safety facility in terms of Asset Management(AM). As the road safety facilities related among them are very diverse, and their functions are very important as well, the regulations and directions for installing them are enacted. However, despite the standards and directions for the installations, sometimes, the facilities are not installed in accordance with the standards, not only causing inconvenience to the users but also negatively affecting the safety for them. In the study, for the facilities in which the installation interval and height are standardized according to the designed speed and geometrical structure of the road among the various road safety facilities, the image analysis model capable of measuring them with a line scanning camera was developed. In addition, the program systematically analyzing this was also developed and applied to the field and, as the result of that, the size and installation interval of the facilities could be measured fast and accurately.
Influence of Processing Conditions on the Physical Properties of Crumb Rubber Modified Asphalts
O, Kwang-Joong ; Kim, Jong-Seok ;
International Journal of Highway Engineering, volume 10, issue 3, 2008, Pages 239~246
In this study, the influence of reaction temperatures, mixing time and flexible modifier for crumb rubber modified asphalt(CRMA) as processing conditions were investigated. The temperature susceptibility and adhesion properties of neat and modified asphalts at low temperature measured using the penetration and tensile adhesion test. It was found that processing temperatures and flexible modifier were important factors for tensile adhesion strength and toughness energy at low temperature. The CRMA in the higher processing temperature and flexible modifier exhibited improved tensile adhesion properties which indicated the flexible structure of neat and modified asphalt binder. In general, the improvements of the physical properties in the CRMAs were due to the improvements of miscibility between CR and asphalt binder. It was found that the adhesion properties of the flexible agent modified CRMA were higher than CRMA were related to the flexible agent tend to penetrate into CR particles and asphalt binder.