• Korean Journal of Agricultural Science
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• v.37 no.2
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• pp.277-283
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• 2010

Research on permeable pavement like asphalt and concrete pavement with porous structure has been increasing due to environmental and functional need such as reduction of run off and flood. This study was performed to evaluate void ratio, permeability coefficient, and compressive strength of permeable polymer concrete (PPC) using crushed and recycled coarse aggregate that is obtained from waste concrete. Also, 6 mm length of polypropylene fiber was used to increase toughness and interlocking between aggregate and aggregate surrounded by binder. Binder and filler used were unsaturated polyester resin and CaCO3, respectively. The mix proportions were determined to satisfy the requirement for the workability and slump according to aggregate sizes 5~10 mm. In the test results, regardless of kinds of aggregates and fiber contents, the void ratio, permeability coefficient and compressive strength of all types of PPC showed the higher than the criterion of porous concrete that is used in permeable pavement in Korea. Also, strengths of PPC with increase polypropylene fiber volume fraction showed slightly increased tendency due to increase binder with increase of fiber volume fraction. Accordingly, polypropylene fiber and recycled coarse aggregate can be used for permeable pavement.

• International Journal of Highway Engineering
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• v.18 no.2
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• pp.11-18
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• 2016

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.

• International Journal of Highway Engineering
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• v.15 no.1
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• pp.95-102
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• 2013

PURPOSES: The existing method evaluating the existence of the hollows in concrete pavement does not consider the stiffness of pavement. In addition, the method uses unreasonable logic judging the hollow existence by the deflection caused by zero loading. In this study, the deflection of slab corner due to heavy weight deflectometer (HWD) was measured in concrete pavement sections where underground structures are located causing the hollows around them. METHODS: The modulus of subgrade reaction obtained by comparing the actual deflection of slab to the result of finite element analysis was calibrated into the composite modulus of subgrade reaction. The radius of relative stiffness was calculated, and the relationship between the ratio of HWD load to the radius of relative stiffness and the slab deflection was expressed as the curve of secondary degree. RESULTS: The trends of the model coefficients showing width and maximum value of the curve of secondary degree were analyzed by categorizing the pavement sections into three groups : hollows exist, additional investigation is necessary, and hollows do not exist. CONCLUSIONS: The results analyzed by the method developed in this study was compared to the results analyzed by existing method. The model developed in this study will be verified by analyzing the data obtained in other sections with different pavement structure and materials.

• International Journal of Highway Engineering
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• v.20 no.3
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• pp.65-73
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• 2018

PURPOSES : In this study, the propriety of expansion joint spacing of airport concrete pavement was examined by using weather and material characteristics. METHODS : A finite element model for simulating airport concrete pavement was developed and blowup occurrence due to temperature increase was analyzed. The critical temperature causing the expansion of concrete slab and blow up at the expansion joint was calculated according to the initial vertical displacement at the joint. The amount of expansion that can occur in the concrete slab for 20 years of design life was calculated by summing the expansion and contraction by temperature, alkali-silica reaction, and drying shrinkage. The effective expansion of pavement section between adjacent expansion joints was calculated by subtracting the effective width of expansion joint from the summation of the expansion of the pavement section. The temperature change causing the effective expansion of pavement section was also calculated. The effective expansion equivalent temperature change was compared to the critical temperature, which causes the blowup, according to expansion joint spacing to verify the propriety of expansion joint applied to the airport concrete pavement. RESULTS : When an initial vertical displacement of the expansion joint was 3mm or less, the blowup never occurred for 300m of joint spacing which is used in Korean airports currently. But, there was a risk of blow-up when an initial vertical displacement of the expansion joint was 5mm or more due to the weather or material characteristics. CONCLUSIONS : It was confirmed that the intial vertical displacement at the expansion joint could be managed below 3mm from the previous research results. Accordingly it was concluded that the 300m of current expansion joint spacing of Korean airports could be used without blowup by controling the alkali-silica reaction below its allowable limit.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.137-138
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• 2009

This study was conducted to analyze the behavior of PTCP (Post-Tensioned prestressed Concrete Pavement) under tensioning by performing field tests when the experimental PTCP slab was being constructed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.171-174
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• 2009

This study analyzes the change of the basic characteristics of pavement concrete according to the reinforcement of macro-fiber and the results of the study can be summarized as follows. In the case of the compressive strength of the concrete, the fiber reinforced pavement concrete shows a small decreasing level compared to the basic mixing of pavement concrete (hereafter referred as 'Plain') based on the aging of 28 days. In particular, the polypropylene fiber made in Korea represents a decrease in the strength about 12% compared with that of the Plain. In the case of the tensile strength, it shows certain improvements in the tensile performance compared with that of the Plain. In particular, in the case of the polyvinyl alcohol fiber that shows the largest improvement in tensile performance, it shows an increase in its strength about 21%. In the case of the bending strength, there are no improvements in its strength in the fiber reinforced concrete compared to that of the Plain.

• International Journal of Concrete Structures and Materials
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• v.18 no.3E
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• pp.145-150
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• 2006

An experiment with the objective of providing guidelines for joint depth determination and timing of contraction joint sawcutting to avert uncontrolled cement concrete pavement cracking has been conducted. Theoretical analysis and laboratory tests were performed to help in understanding and analyzing the field observation. Using two-dimensional elastic fracture mechanics, the influence of several parameters on crack propagation was delineated by a parametric study, involving initial notch ratio, joint spacing, Young's modulus and thermal expansion coefficient of concrete, temperature gradient, and modulus of subgrade reaction. Bimaterials made of rock plus cement mortar and rock plus polymer mortar were applied to the concrete in a field test section, and they were subjected to fracture tests. These tests have shown that fracture mechanics is a powerful tool not only in judging the quality of the jointed cement concrete pavement but also in providing a criterion for crack propagation and delamination. Based on fracture mechanics, a method is proposed to determine the joint depth, sawcut timing, and spacing of the jointed cement concrete pavement. This method has successfully been applied to a test section in Seohaean expressway. This study also summarizes the research results obtained from a field test for jointed plain concrete pavement, which was also carried out on the Seohaean expressway.

• Journal of Industrial Technology
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• v.23 no.A
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• pp.165-173
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• 2003

The purpose of this paper is to analysis of initial behavior of concrete pavement with initial measurement strain gauge for concrete pavement at field, and to investigate the field test results for field applicability testing. The early-age behaviors of concrete pavement slabs were measured using the strain gauges. From the slab depths and positions, the outputs from each gauges were recorded at initial curing period. The initial measurement of concrete pavement and check of crack at the joint were performed, the results could be summarized as follows. From the results of concrete strength, compressive strength and flexural strength were showed $271kgf/cm^2$, $43kgf/cm^2$ respectively. From the tests of early-age strain measurement, it was found that the strain varied at the maximum value of $150{\mu}{\varepsilon}$ and early behavior of concrete slab was showed a tensile strain. However, for long-term was showed a compressive strain due to dry-shrinkage.

• International Journal of Concrete Structures and Materials
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• v.10 no.1
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• pp.39-46
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• 2016

In this study, different proportions of glass beads used for road marking were added into the concrete samples to reduce the temperature gradient through the concrete pavement thickness. It is well known that decreasing the temperature gradient reduces the risk of thermal cracking and increases the service life of concrete pavement. The extent of alkali-silica reaction (ASR) produced with partial replacement of fine aggregate by glass bead was investigated and compressive strength of concrete samples with different proportion of glass bead in their mix designs were measured in this study. Ideal results were obtained with less than 0.850 mm diameter size glass beads were used (19 % by total weight of aggregate) for C30/37 class concrete. Top and bottom surface temperatures of two different C30/37 strength class concrete slabs with and without glass beads were measured. It was identified that, using glass bead in concrete mix design, reduces the temperature differences between top and bottom surfaces of concrete pavement. The study presented herein provides important results on the necessity of regulating concrete road mix design specifications according to regions and climates to reduce the temperature gradient values which are very important in concrete road design.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.461-464
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• 2003

Portland Cement Concrete (PCC) pavements have the advantage of durability and superior surface friction when compared to most dense-graded asphalt. However, data collected to date generally show PCC pavements to create more noise than asphaltic surfaces. As the results of research, surfaces of exposed aggregate, tining and grooving concrete pavements appear to provide better noise quality characteristics as well as good frictional characteristics and durability. In this paper, several methods of texturing were considered to reduce tire/pavement noise. As the results of this paper, PCC pavements with special texturing have superior surface friction as well as noise reductions when compared to conventional PCC pavement. Especially, Exposed Aggregate Concrete (EAC) surface appears to provide better noise quality characteristics. Conclusively, if overall noise and safety are considered simultaneously, EAC pavement that provides satisfactory friction as well as better noise reductions is suggested.