• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.3
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• pp.178-185
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• 2011

Recently depletion of natural resources makes a deficiency of sand aggregation in the concrete works. In this study, the quality characteristics of concrete and aggregate according to blending fine aggregate in the river sand and the crash sand was analyzed by Normal method and Driscoll method which has used mixing of fine aggregate for asphalt mostly. Application of Discoll method to blend fine aggregate for concrete was studied in the first step to blend fine aggregates concrete. The fineness modulus, grading, slump, air content and compressive strength were tested by the two method, the results of Driscoll method was very similar to degree of err limits in comparison with those of Normal method in the same condition. As a result, Driscoll method is reasonable to use the fine aggregates mixture for concrete in river sand and crash sand.

• International Journal of Highway Engineering
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• v.4 no.4 s.14
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• pp.23-39
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• 2002

This study dealt with developing a new approach for finding properties which might represent rut resistance characteristics of asphalt mixture under static loading. Two aggregates, a normal asphalt (pen 60-80) and 5 polymer-modified asphalts were used in preparation of 12 dense-graded mixtures. Marshall mix design was used in determination of OAC and each mixture at the OAC was prepared for a newly-developed Kim test on Marshall specimen (S=10cm) and gyratory specimen (S=15cm), and for wheel tracking test. Kim test used Marshall loading frame and specimens were conditioned for 30min at $60^{\circ}C$ before loading through Kim tester an apparatus consisting of a loading column and a specimen and column holder Diameter (D) of column was 3cm and 4cm with each column having different radius (r) of round cut at the bottom. The static load was applied at 50mm/min in axial direction of the specimen, not in diametral direction. The maximum load ($P_{max}$) and vertical deformation (y) at $P_{max}$ point were obtained from the test. A strength value was calculated based on the $P_{max}$ r, D and y by using the equation $K_D = 4P_{max}/{\pi}(D-2(r-\sqrt{2ry-y^2}))^2$ and is defined as the deformation strength ($kgf/cm^2$). The values of $P_{max}$/y and $K_I=K_D/y$ were also calculated. In general the leading column diameter and radius of round cut were significant factors affecting $K_D$ and $P_{max}$ values while specimen diameter was not. The statistical analyses showed the $K_D$ had the best correlation with rut depth and dynamic stability. The next best correlation was found from $P_{max}$ which was followed by $P_{max}$/y and $K_I$ in order.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.4
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• pp.931-940
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• 2015

Roller Compacted Concrete Pavement (RCCP), is a type of pavement using compaction roller and asphalt finisher on concrete mixture that contains low amount of water. RCCP strength and durability are greatly affected by compaction level. Quality control is performed by ensuring the degree of compaction at site based on dry density. In the field, Modified Proctor Test is used in order to obtain optimum dry density. However, there is no clear compaction curve analysis criteria of Modified Proctor Test for RCCP. In this study, compaction curve built by three samples of Modified Proctor Test was produced and it was used to compare with compaction curve contented lower number of samples (one and two samples) in order to analyze their reliability. Thus, a conclusion was drawn from the results; by comparing to the result from Modified Proctor Test of three samples, the use of two samples represented result with only 0.5% of error which means the reliability is 99.5%.

• International Journal of Highway Engineering
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• v.20 no.1
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• pp.87-95
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• 2018

PURPOSES : A geo-grid pavement, e.g., a stress-absorbing membrane interlayer (SAMI), can be applied to an asphalt-overlay method on the existing surface-pavement layer for pavement maintenance related to reflection cracking. Reflection cracking can occur when a crack in the existing surface layer influences the overlay pavement. It can reduce the pavement life cycle and adversely affect traffic safety. Moreover, a failed overlay can reduce the economic value. In this regard, the objective of this study is to evaluate the bonding properties between the rigid pavement and a SAMI by using the direct shear test and the pull-off test. The predicted fractural energy functions with the shear stress were determined from a numerical analysis of the moving average method and the polynomial regression method. METHODS : In this research, the shear and pull-off tests were performed to evaluate the properties of mixtures constructed using no interlayer, a tack-coat, and SAMI with fabric and without fabric. The lower mixture parts (describing the existing pavement) were mixed using the 25-40-8 joint cement-concrete standard. The overlay layer was constructed especially using polymer-modified stone mastic asphalt (SMA) pavement. It was composed of an SMA aggregate gradation and applied as the modified agent. The sixth polynomial regression equation and the general moving average method were utilized to estimate the interlayer shear strength. These numerical analysis methods were also used to determine the predictive models for estimating the fracture energy. RESULTS : From the direct shear test and the pull-off test results, the mixture bonded using the tack-coat (applied as the interlayer between the overlay layer and the jointed cement concrete) had the strongest shear resistance and bonding strength. In contrast, the SAMI pavement without fiber has a strong need for fractural energy at failure. CONCLUSIONS : The effects of site-reflection cracking can be determined using the same tests on cored specimens. Further, an empirical-mechanical finite-element method (FEM) must be done to understand the appropriate SAMI application. In this regard, the FEM application analy pavement-design analysis using thesis and bonding property tests using cored specimens from public roads will be conducted in further research.

• International Journal of Highway Engineering
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• v.12 no.1
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• pp.29-37
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• 2010

Porous pavements can provide road users with beneficial characteristics such as skid resistance and surface water drainage under rainy condition, and they cause less tire-road noise than conventional hot mix asphalt(HMA) pavements. However, voids of porous pavements are easily clogged by road debris at early stages, which leads to frequent maintenance works. Therefore, this study focused on the way of minimizing void clogging in porous pavements. During mixture design, the quantity of coarse aggregate has been increased to form many straight void conduits (SVCs) in porous HMAs. These SVCs were found to be effective resisting the void clogging problems. Four different porous HMAs(19mm, 13mm, 10mm, and 8mm) were developed and placed on highway roads. Their performances were validated with field tests during the past four years.

• International Journal of Highway Engineering
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• v.15 no.4
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• pp.53-63
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• 2013

PURPOSES: The purpose of this study was to investigate the disintegration mechanism of concrete due to the infiltration of the moisture to the milling overlay pavement and to come up with a method to minimize the disintegration as well as verifying the effectiveness of the edge sealing and Fogseal method. METHODS : This study investigated the distress mechanism due to the infiltrated moisture remaining in the milling overlay pavement through chloride freezing test and verified the effectiveness of the sealing of the milling edge and fog seal methods, which have been devised to minimize the moisture infiltration, through laboratory water permeability test. Additionally, long-term pavement performance was compared for the effectiveness of the proposed method through under loading test, and field water permeability test was carried out to verify the field applicability of the proposed method. RESULTS: The result of the research confirmed that chloride deteriorates the concrete surface through disintegration and lowers its strength and that the laboratory moisture infiltration test verified the effectiveness of the milling edge sealing and fog seal methods in the deterrence of moisture infiltration to the overlay pavement with excellent long-term performance of the pavement treated with the proposed method. Although the field water permeability test revealed some deterrence of moisture infiltration of the milling edge sealing and fog seal methods to a certain extent, the difference was a little. CONCLUSIONS: The milling edge sealing and fog seal methods are limited in their effectiveness for the cases of improvident compaction management or mixture with large void, and it is believed that installation of subsurface drainage is more effective in these cases.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.6
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• pp.737-744
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• 2021

Spray paving minimizes material lost during the construction or repair of a road surface, and it can be done in conjunction with tack coating. This approach involves applying the asphalt mixture at the same time as spraying the tack coat by attaching a spraying device to the asphalt paver. When applying an asphalt overlay to an aged concrete surface, it is important to ensure the adhesion performance between different material properties. Accordingly, there is a need for a tack coat that can be applied by spray paving and that exhibits good adhesive performance on different materials. In this study, bonding strength tests under various conditions were performed to evaluate the basic performance of a tack coat developed for use with a spray paver. The bonding performance of the tack coat was observed to be affected by curing conditions and material lost during construction. The test results also showed that the tensile and shear bonding strengths of the developed tack coat were 1.21 and 1.99 times higher than those of a conventional one, respectively. As a result, the developed tack coat is considered suitable for application to spray paving.

• Advances in materials Research
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• v.13 no.1
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• pp.63-86
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• 2024

Asphalt concrete (AC), is a mixture of bitumen and aggregates, which is very sensitive in the design of flexible pavement. In this study, the Marshall stability of the glass and carbon fiber bituminous concrete was predicted by using Artificial Neural Network (ANN), Support Vector Machine (SVM), Random Forest (RF), and M5P Tree machine learning algorithms. To predict the Marshall stability, nine inputs parameters i.e., Bitumen, Glass and Carbon fibers mixed in 100:0, 75:25, 50:50, 25:75, 0:100 percentage (designated as 100GF:0CF, 75GF:25CF, 50GF:50 CF, 25GF:75CF, 0GF:100CF), Bitumen grade (VG), Fiber length (FL), and Fiber diameter (FD) were utilized from the experimental and literary data. Seven statistical indices i.e., coefficient of correlation (CC), mean absolute error (MAE), root mean squared error (RMSE), relative absolute error (RAE), root relative squared error (RRSE), Scattering index (SI), and BIAS were applied to assess the effectiveness of the developed models. According to the performance evaluation results, Artificial neural network (ANN) was outperforming among other models with CC values as 0.9147 and 0.8648, MAE values as 1.3757 and 1.978, RMSE values as 1.843 and 2.6951, RAE values as 39.88 and 49.31, RRSE values as 40.62 and 50.50, SI values as 0.1379 and 0.2027 and BIAS value as -0.1 290 and -0.2357 in training and testing stage respectively. The Taylor diagram (testing stage) also confirmed that the ANN-based model outperforms the other models. Results of sensitivity analysis showed that the fiber length is the most influential in all nine input parameters whereas the fiber combination of 25GF:75CF was the most effective among all the fiber mixes in Marshall stability.

• International Journal of Highway Engineering
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• v.13 no.2
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• pp.159-166
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• 2011

This research was performed to evaluate physical properties of polysulfide epoxy overlay material for bridge deck as part of a review for possibility of domestic application of polymer concrete for bridge deck pavement. In order to evaluate strength characteristics, compressive strength, flexural strength and bond strength were tested, and, for durability characteristics, chloride ion penetration resistance and freeze/thaw resistance were tested along with ultraviolet rays impact evaluation. The tests showed that the results met the criteria suggested by the American Concrete Institute in terms of compressive strength, flexural strength and bond strength. However, in terms of the strengths measured at various test temperatures, it was found that the epoxy material was highly dependent on temperature, and, therefore, this should be considered at the time of domestic application of the epoxy material later. Deflection characteristics was checked through flexural strength test and it was found that bridge deck pavement using the epoxy material was excellent compared to bridge deck pavement using asphalt. Furthermore, the results of chloride ion penetration resistance test and freeze/thaw resistance test were also excellent. In the evaluation of ultraviolet rays impact on epoxy slurry mixture, reduction of strain was noticed with increased strength, but the deflection characteristics after exposure to ultraviolet rays was better than the existing acryl polymer concrete. Therefore, it is concluded from the research that the polysulfide epoxy overlay material has the physical properties that are appropriate to pavement of bridge deck.

• The Journal of the Korea Contents Association
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• v.12 no.3
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• pp.449-460
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• 2012

Since 1970's, the rivers in industrial cities and metropolitan cities in Korea have been severely contaminated and the riverfronts have been to garbage yard, warehouses and sanitary facilities that produce low efficiency in urban land-use. As a result, riverfront in most cities became lost space and artificial area which composed of asphalt road, concrete riverbank and parking lot. However, Sustainable management is the main concept of riverfront development in 21st century. Also, in contemporary riverfront space, it is the pivotal paradigm that the development of eco-space and mixture of cultural space. Citizen require greener, more ecological and water-friendly space in riverfront of city. So, the purpose of this paper lies in suggestion for building sustainable development and management for riverfront in Korean city. For this purpose, this paper has reviewed the developmental trend of recent riverfront, has analyzed locational environment and land use of riverfront in city, has set policy and the strategy for sustainable riverfront.