• 한국도로학회:학술대회논문집
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• 2009.11a
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• pp.647-652
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• 2009

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.3
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• pp.53-59
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• 2018

This study analyzed the field applicability through the combination of environment-friendly grid-typed reinforcements and pre-mixed fiber with filler. The film of the grid-typed reinforcement is made by recycled PE resin. And, Ascon fiber is obtained the dispersion by pre-mixing of filler. To be able to recognize in advance the various circumstances that could arise in the construction of the road pavement layer, we conducted a basic field application test of the (Mock Up) pavement layer. As a result, it was found that the pavement with environment-friendly grid-typed reinforcement and dispersive fiber construction had improved strength, stress, and rutting resistance. It is consistent with the strength and stress results of the actual test of the mock up specimen. It is expected to perform an effective role in the safety as well as the use of environment-friendly fibers in actual construction.

• Journal of Industrial Technology
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• v.17
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• pp.199-204
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• 1997

In this paper, the result of application of vibration method to the orthotropic plates with free edges supported on elastic foundation and with a pair of opposite edges under axial forces is presented. Such plates represent the concrete highway slab and hybrid composite pavement of bridges. The reinforced concrete slab can be assumed as a special orthotropic plate, as a close approximation. The highway slab is supported on elastic foundation, with free boundaries. Sometimes, the pair of edges perpendicular to the traffic direction may be subject to the axial forces. The plate is subject to the concentrated load/loads, in the form of traffic loads, or the test equipments. Finite difference method is used to obtain the deflection influence surfaces needed for vibration analysis. The influence of the modulus of the foundation, the aspect ratio of the plate, and the magnitudes of the axial forces and the concentrated attached mass on the plate, under the natural frequency is thoroughly studied.

• Journal of the Korean Wood Science and Technology
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• v.47 no.1
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• pp.51-65
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• 2019

A wood-plastic composite (WPC) paver block was manufactured using wood chips waste through an extrusion process, and it was intended to be used for paving in basic rest areas. The first stage in this study covered preliminary tests in terms of flexural strength and dimensional swelling to determine the optimal WPC compounding mix condition, by variation of the WPC ingredients. Next, three different paver blocks including the WPC block, a non-porous cement block, and a porous cement block were tested in terms of various material properties in the laboratory. Finally, two outdoor test sections of the proposed paver blocks were prepared to simulate a basic rest area. Test results indicated that the flexural strength of the WPC paver blocks was about 1.6 times greater than that of the tested cement paver blocks. The WPC block pavement was unaffected by water buoyance as well as volume expansion due to swelling. Results from the impact absorbance test and light falling weight deflectometer (LFWD) test clearly showed that the WPC block paving system marginally satisfied the comfortable and safe hardness range from the pedestrians' perspective, while the results demonstrated that it is structurally sound for application as a road paving block.

• Journal of the Society of Disaster Information
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• v.8 no.3
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• pp.234-241
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• 2012

The main objective of this research is to calibrate the performance prediction models for the growth of fatigue cracking in multi-layered asphalt concrete pavement systems. However, the calibration factors are dependent upon the prediction model, testing method, and the laboratory loading history. A detailed study on the field data has revealed that the performance of flexible pavements is affected by both the traffic loading and the environmental cycling which is related to the age of the pavements. Thus, a composite indicator was developed in this study which utilizes both the traffic and the age information with appropriate weighting factors. Using the proposed fatigue performance model the calibration factors were also estimated through the comparisons between the field performances on fatigue cracking and the laboratory-based fatigue life.

• International Journal of Highway Engineering
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• v.16 no.2
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• pp.91-98
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• 2014

PURPOSES : The objective of this study is to investigate the effect of asphalt and geotextile interlayer on the fracture behavior of unbonded concrete overlay through a laboratory composite beam test. METHODS : In order to evaluate the effect of interlayer materials on the fracture behavior of unbonded concrete overlay, a laboratory test of composite beam was conducted with different types of interlayer. The test results of the composite beam using two types of geotextile interlayer with different thicknesses were compared to the test results of the composite beam using the tradition type of asphalt interlayer. The unbonded concrete overlay on the existing concrete pavement without interlayer was set for the control condition. RESULTS AND CONCLUSION : Overall, the laboratory composite beam test results did show the effect of asphalt and geotextile interlayer on the fracture behavior of composite concrete beams. The three-layer geotextile interlayer and HMA layer both increase the peak load when the first macrocrack occurs in the top concrete beam, while the HMA interlayer causes the smallest load drop percentage after the first macrocrack. The three-layer geotextile did show better performance than the single-layer geotextile through the greater peak load and smaller load drop percentage. It indicates that the thickness of geotextile interlayer will affect the fracture behavior of unbonded concrete overlay and the thicker geotextile interlayer is recommended.

• Composites Research
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• v.12 no.4
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• pp.25-32
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• 1999

A method of calculating the natural frequency corresponding to the first mode of vibration of beams and tower structures, with irregular cross sections and with arbitrary boundary conditions was developed and reported by Kim, D. H. in 1974. In this paper, the result of application of this method to the special orthotropic plates on elastic foundation with free boundaries is presented. Such plates represent the concrete highway slab and hybrid composite pavement on bridges. Any method may be used to obtain the deflection influence surfaces needed for this vibration analysis. Finite difference method is used for this purpose, in this paper. The influence of the modulus of the foundation and the aspect ratio of the plate on the natural frequency is thoroughly studied. The effect of neglecting the mass of the plates on the natural frequency, as the ratio of the point mass/masses to the plate mass increases, is also studied, in deep.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.04a
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• pp.327-334
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• 1998

A method of calculating the natural frequency corresponding to the first mode of vibration of beams and toll.or structures, with irregular cross sections and with arbitrary boundary conditions was developed and reported by Kim, D. H. in 1974. In this paper, the result of application of this method to the special orthotropic plates with free edges supported on elastic foundation and with a pair of opposite edges under axial forces is presented. Such plates represent the concrete highway slab and hybrid composite pavement of bridges. The reinforced concrete slab can be assumed as a special orthotropic plate, as a close approximation. The highway slab is supported on elastic foundation, with free boundaries. Sometimes, the pair of edges perpendicular to the traffic direction may be subject to the axial forces. The plate is subject to the concentrated load/loads, in the form of traffic loads, or the test equipments. Any method nay be used to obtain the deflection influence surfaces needed for this vibration analysis. Finite difference method is used for this purpose, in this paper. The influence of the modulus of the foundation, the aspect ratio of the plate, and the magnitudes of the axial forces and the concentrated attached mass on the plate, on the natural frequency is thoroughly studied.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.529-532
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• 2008

Recently the compound material has interested in using the structural material as the bridge member assembly. It is the lighter material against existing construction material and has excellent durability and economy. The existing floor of bridge has its short period to repair and replace compared to other parts of the bridge with the pavement and the shoe. These deteriorations of usage and safety by aging and corrosion are needed frequent maintenance. The use of compound material as a structural member suggests solve these problems. So this thesis evaluates the static and the fatigue performance for whether there are fiber lamination direction and stress concentration section of FRP floor plate, the compound material.

• International Journal of Highway Engineering
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• v.11 no.3
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• pp.111-120
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• 2009

Recently, pay adjustment regulation (PAR) has been developed to induce better performing road pavements around the country. This regulation was successfully applied during rehabilitation of highway flexible pavements for the first time, and their results are the focus of this paper. For highway pavements, a lot has been defined by typical amount of works a day. This lot was further divided into several sublots depending on field conditions. According to AASHTO Quality Assurance Guide Specification, pay factors for each lot were statistically determined with field measurements of five performance indicators. And composite pay factors were calculated by accounting for the impact of individual performance indicators on a long-term performance of pavement. In 2008, the PAR was tested with asphalt overlays conducted at all six local headquarters of Korea Expressway Corporation. Also, concerns raised during implementation are discussed in this paper. Limited data used in this study showed that if all performance indicators fall within the construction limits with less variances final construction costs may increase by 50%, whereas 10% reduction in construction costs could be necessary if key performance indicators such as density do not meet the construction quality requirements.