• 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.

• Journal of Soil and Groundwater Environment
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• v.10 no.5
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• pp.37-44
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• 2005

The main object of this study is to develop the infiltration facility that it can be used in grounds, parking areas, roads, pathway, housing etc. As a result, it is much alike in the infiltration method of facility to use permeable concrete, permeable hole and be filled with broken stones. And through this experiment, it was perceived the truth that the state of ground, the groundwater level, buildings around them, the history of submerging and the applicable infiltration facilities are the key. To verify how much the infiltration facility reduce the outflow, we set up the infiltration facility in the test area. In result, it reduced the outflow 89% in 24 mm rainfall, 93% in 12 mm, 51% in 140 mm, 75% in 64 mm and 80% in 54 mm. As the rainfall rate increased, the infiltration increased up to the limited rainfall. And in the limited rainfall, we knew that the infiltration was reduced suddenly. Infiltration is closely related to the state of ground, the rain interval etc. and we will analyze these conditions through the continuous monitoring.

• International Journal of Highway Engineering
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• v.5 no.3 s.17
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• pp.31-42
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• 2003

The KHC Test Road project was initiated on 1991 to develop Korean Pavement Design Guide. It was constructed along the Joongbu Inland Expressway line between Yeoju and Gamgok. It is two-lane wide expressway containing fifteen asphalt and twenty-five Portland cement concrete test pavement sections. Various sensors were installed in the Test Road to evaluate the behavior of test pavement sections under the influence of traffic load and environmental change. The most important issues in the sensor installation are the accurate location and long-term survivability. They are directly influenced by the sensor installation methodology. The methodology for asphalt strain gages is mainly discussed in this paper because it is the second important sensors in the KHC Test Road project. In order to find the best methodology, we evaluated existing methodology from prior experience and several conducted test installations. We have tried mound, block out, and trench cuts since 2000. Among three methods, block out was the most effective one in terms of accurate location, long-term survivability, and material homogeneity. However, this method cannot be applied to the wearing coarse so that the mound method was used as an alternative. The block out method was applied to base and intermediate layers while the mound method was used to the wearing coarse. Three hundred seventy-four asphalt strain gauges were installed on asphalt pavement sections from September 3rd to November 18th in 2002. According to the sensor measurement evaluation, 6.3% of sensor demonstrated over ranged readings for mound method installation and 2.5% did for block out method installation. We lost only two sensors during the installation. It is 99.5% survival and it is excellent survival rate according to other experience.