• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.611-614
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• 2005

It is well known that tire tread pattern has much influence on the tire pattern noise. The paper describes the method of pattern noise reduction by using the pitch sequence, both on the smooth asphalt roads and on the trenched concrete roads. The noise of tire is classified as either airborne or structure borne noise. Pattern noise through the airborne is considered as a major noise source at high speeds. As block impacting and air pumping by tread patterns are major noise source, tire pattern noise can be greatly influenced by optimal pitch sequence. The goal of this paper is to provide tire engineers with pitch sequence to reduce pattern noise effectively.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.107-108
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• 2023

In this study, the tensile adhesion strength was evaluated according to KS F 4932 to assess the suitability of MMA-based repair materials for concrete roads. Two types of MMA were used. Mortar mock-ups were made and tested for adhesion strength in three different surface conditions: air, water, and salt water. Both showed strengths above the standardized strength of 0.6 MPa. Type B, which has a relatively low adhesion strength, is considered more suitable.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.3
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• pp.9-12
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• 2013

The pavement is generally used on the highways, local loads, roads for bicycle riding and neighborhood living facility such as parking lot, plaza, park and sports facilities. However, the pavement material that is usually used on the most of roads is impermeable asphalt-concrete and cement-concrete. If the pavement material is impermeable, many problems can be happened on the drainage facilities in the rainy season. Additionally, a lot of rainwater on the pavement surface cannot permeate to the underground and flows to the sewage ditch, stream and river, etc. If a lot of rainwater flows at once, the floods can be out along the streams and rivers. So, underground water can be exhausted. Micro organisms cannot live in the underground. Recently, many studies has been conducted to exploit the permeable concrete that has high performance permeability. However, it is required to develop the permeable concrete which has high strength and durability. In this study, permeable and strength tests were performed to investigate the permeable characteristics of porous concrete according to fine aggregate content and substitution ratio of blast furnace slag. In this test, crushed stones with 10~20 mm and sand with 5~10 mm were used as a coarse aggregate and a fine aggregate respectively. The substitution ratio of blast furnace slag to cement weight is 0 %, 15 %, and 30 %. The ratio of fine aggregate to total aggregate is 0 %, 18 %, and 35 %. As a result, permeability coefficient was decreased according to fine aggregate ratio of total aggregate. Compressive strength was also decreased according to substitution ratio of blast furnace slag.

• International Journal of Highway Engineering
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• v.6 no.1 s.19
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• pp.25-36
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• 2004

The total length of paved roads in Korea is 67,265 Km, and among these roads, about 40% of the national highways and 98% of local roads are paved with asphalt concrete. The major distress to asphalt pavement is rutting and fatigue crack. The permanent deformation including rutting accounts for about 75% of this distress. UTW(Ultra-Thin Whitetopping), which is known for its high-quality performance in asphalt pavement with rutting and cracking, seems to reduce maintenance costs significantly if it is used as the maintenance/repair method for domestic asphalt pavement. In the research, static load test was conducted to establish a behavior of Whitetopping under traffic and environmental condition. It showed that the effect of the thickness of the concrete layer and the temperature change was significant. In addition, the tensile strain as the wheel load position was close to interior and edge of concrete slab were increased up to 75% of maximum tensile strain. It showed that joint spacing must be considered in UTW design procedure.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.6
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• pp.90-96
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• 1999

Over 4.1 billion metric tons of non-hazardous solid wstes are generated in the United States annually. Therefore, there is a need to reuse or reprocess as many products or by-products as possible. In this report, theaggregates produced from Naval Shipyard and Charleston area dredge spoils are designated as GP-21-23 and GP 4-5, repectively. The major objective of this study is to determine the feasiblity of the use of these aggregates in concrete. The followings are some of the conclusions, observations and recommendations regarding this portion of the research project. In most cases, the unit weight of concrete containing GP 21-23 and GP 4-5 (vitrified galss) lower than the control concrete, and the concrete containing vitrified glass produced lower compressive and bending strength compared to the control. However the concrete containing virtrified glass could be used in the field based on the minimum criterial set for the mix design. The use of vitrified glass in concrete is recommended in several applications except parking lots, side walks and main roads, because abrasion resistace is not high.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.1227-1232
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• 2000

In this study the mechanical properties of various wire mesh reinforcing porous concrete mixtures are investigated. A properly designed porous concrete pavements provides a durable riding surface. It also eliminates puddles and standing water, resulting in improved skid resistance. The most popular application is that of light-traffic volume roadways such as parking lots, resident roads, driveways, and sidewalks. Flexural strength and toughness index are examined for wire mesh reinforcing porous concrete. Type of Wire mesh is divided into three cases, A type, B type and C type. It shows A type is most excellent shape of destruction of slab specimen is similar to that of flexural specimen. The aim of this paper is to present the results of a pilot study undertaken to examine the extent to which wire mesh reinforced porous concrete can be used as a continuous paving materials.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.356-361
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• 1998

Permeable polymer cement concrete in this study is one of the invironment conscious concretes that can be applied at roads, side walks, parking lots, interlocking block and river embankment, etc. In this study, permeable polymer cement concretes using polymer dispersion(St/Ac) with water-cement ratios of 25, 30, 35 and 40%, polymer-cement ratios of 0, 5, 10, 15 and 20%, and a ratio of cement to aggregate (by weight), 1 : 3.5(about 415kg/㎥), 1 : 4.0(about 375 kg/㎥), and 1 : 4.5(about 345kg/㎥) are prepared, and tested for compressive, flexural and tensile strength, and permeability. From the test results, increase in the strengths of permeable polymer cement concrete are clearly observed with increasing polymer-cement ratio, we can obtain the maximum strengths at water-cement ratio of 35%. The optimum permeable polymer cement concrete according to application and location of work can be selected in various mix proportions.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.449-454
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• 1999

Pavement concrete subjected to severe environmental condition may be vulnerable to frost attack practically where de-icing chemicals are used. This study focused on the investigation of durability characteristics of pavement concrete incorporation polypropylene fibers and application feasibility of these into the pavements of local roads and highway. A series of labortory tests were performed with main experimental variable such as fiber types, fiber contents. and type of concrete mix. The test of compressive strength was executed as primary tests, before the durability tests such as a scaling resistance were performed. De-icing salt resistance test was progressed by recycling freeze and thaw in the presence of a 4% calcium chloride solution. The deteriorated surfaces were rated by visual inspection and the loss weight were measured at every 5 cycles.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42
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• pp.78-84
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• 2000

Permeable polymer concrete can be applied to roads, sidewalks, river embankment, drain pipes, conduits, retaining walls, yards, parking lots, plazas, interlocking blocks, etc. This study is to explore a possibility of utilizing industrial by-products, a blast furnace slag and a fly ash, as fillers for permeable polymer concrete. Different mixing proportions are tried to find an optimum mixing proportion of permeable polymer concrete. The tests are carried out at 20$\pm$1$^{\circ}C$ and 60$\pm$2$^{\circ}C$ relative humidity. At 7 days of curing, compressive, flexural and splitting tensile strengths and water permeability ranged between 239~285kgf/$\textrm{cm}^2$, 107~133kgf/$\textrm{cm}^2$, 37~46kgf/$\textrm{cm}^2$ and 4.612~5.913$\ell$/$\textrm{cm}^2$/h, respectively. It is concluded that the blast furnace slag and fly ash can be used in permeable polymer concrete.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.723-726
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• 2004

Porous polymer concrete can be applied to roads, sidewalks, river embankment, drain pipes, conduits, retaining walls, yards, parking lots, plazas, interlocking blocks, etc. This study is to examine a content ratio of polypropylene fiber to improve bending strength, impact resistance and freezing and thawing rssistance of porous polymer concrete. Also, this study is performed to develop the porous polymer concrete using recycled coarse aggregate and blast furnace slag for application of structures needed permeability. At 7 days of curing, compressive strength, flexural strength, water permeability and flexural load are in the ragge of $17\~21MPa,\;5\~7MPa,\;4.1\times10^{-2}\~7.7\times10^{-2}cm/s$, respectively. It is concluded that the recycled aggregate can be used in the porous polymer concretes.