• The Journal of the Acoustical Society of Korea
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• v.35 no.3
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• pp.223-233
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• 2016

Design of a vegetation type sound barrier was presented as a noise barrier on the boundary of neighborhood facilities including schools, and apartments. The suggested noise barrier is made of unit blocks that are to be formed by stacking over the wall structure containing the plant and soils in the blocks. The advantage of the vegetation noise barrier is to acquire not only sound absorptive effects of plants and soils, but also sound diffusive effect caused by the irregular surface of the barrier which could eventually mitigate the noise. First, the optimum size of the units to obtain the highest noise reduction was investigated using 1/10 scaled model experiment, and sound attenuation experiments were carried out using a 1/2 mock-up model which is 2 m high and 5 m long. Total 1,137 unit blocks were made of synthetic woods with the size of $10{\times}10{\times}9cm$. These unit blocks were installed on the both side of the 1/2 mock-up steel framed noise barrier. As a result, it was revealed that the block typed vegetation noise barrier has 7 dB higher insertion loss in comparison with the general plane noise barrier. Also, it was found that the appropriate size of unit blocks is $20{\times}20cm$ which has large effect of sound insertion loss.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.1
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• pp.20-26
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• 2000

In order to propose the design and installation information of vegetation belt, field investigation were carried out in the noise pollution control facilities of highway and the streets of a city for two years(1998~1999), and field tests were performed to analyze the noise attenuation effect of them. The noise pollution control facilities were generally classified into three types (noise barrier and vegetation belt type, mounding and vegetation belt type, vegetation belt type only). Most soundproof facilities were proved the noise reduction effects. But according to width, height, structure, auditory distance and planting forms of them, difference of noise reduction effects were investigated. The soundproof facility was suitable the mounding and vegetation belt type in the consideration of road environment, and the installation standard of vegetation was estimated that the width of vegetation was at least 20m and the length of that was 2 times in the distance from noise source.

• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.2
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• pp.205-212
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• 1995

The effects of noise attenuation among bare land, grassland, dominated broad-leaved (Quercus acutissima Carruth) and dominated coniferous forest (Pignus rigid Mill.) were studied For this study, the field experiment was carried out at playground, orchard grass, and school forest in Yeungnam University, Kyongsan. Sound levels of 500, 630, 800, 1,000, 1,250, 1,600, 2,000, 2,500 and 3,150 Hz, respectively, were projected into the vegetation, and the transmitted levels of sound were recorded at the distances of 1, 5, 10, 20, 30 and 50m, respectively, from the sound source. Both dominated coniferous forest (Pignus riged Mill.) and broad-leaved forest (Quercus acutissima Carruth ) are the more effective than grassland in the rates of attenuation. It is expected that dominated coniferous forest will be the more effective to attenuate sound love교 than dominated broad-leaved forest. In the low frequencies such as 500 and 630 Hz, grassland showed the more effective to attenuate sound levels than forests, while in the high frequency such as 3,150 Hz, the forests are the more effective to attenuate sound levels than grassland The present results suggested that it is the more effective to establish the tree belt for a sound barrier, with dominated coniferous tree species in the upper layer and herbaceous vegetation in the lower layer.

• Tunnel and Underground Space
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• v.10 no.1
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• pp.80-91
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• 2000

Open cut mining of limestone is generally considered to be more advantageous than underground mining in recovery, grade control, economics, and safety, but it causes substantial environmental pollutants such as ground vibration, noise, dust. It also changes ground surface and may destroy vegetation. The Halla limestone mine which lies adjacent to Baikdu mountains range is selected for a model study. To reduce environmental hazards, and to conserve original surface and woods, both open cut and underground mining methods must be adopted. In case of sub-level sloping. a unit block of 87m high, 70m wide, and 100∼l20m long is suggested with an estimated overall recovery of 42%. Some suggestions to reduce the environmental hazards are also included. The followings must be considered in determining the degree of fragmentation; the discontinuity conditions in the rock mass and the charge concentration both at the bottom and column of the hole. In addition to adopting a barrier wall for reducing environmental hazards, the probable production from underground mining is also discussed.