• Journal of the Korean Geosynthetics Society
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• v.5 no.4
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• pp.27-33
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• 2006

Frictional properties between geostrip and sand paper interface were estimated considering soil particle size also the friction coefficients and angles were determined with normal stress. Three kinds of geostrips of design strength 50, 70, 100 KN/m were used and 5 sandpapers of P100, P220, P320, P400, P600 were used also. Shear strength between geostrip and sand paper interface with design strength showed big difference and this is due to the uniform surface pattern of each geostrip when contact to sandpaper without regard to design strength. Shear strength of geostrip was increased with design strength and geostrips/P100 sandpaper interface showed the biggest value. Finally, all of geostrips showed the decrease phenomena of post-peak strength and this is due to the abrasion of geostrip surface by shear test.

• Korean Chemical Engineering Research
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• v.60 no.1
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• pp.132-138
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• 2022

In this study, a basic study was performed to systematically compare the changes in surface properties according to the post-processing method of the stereolithography (SLA) printing method, which is a photocuring 3D printing method, and to provide information on the post-processing method suitable for the application. Although it was possible to improve some of the transparency of the SLA-type output by regularly changing the irregular microstructure of the surface through polishing, it was difficult to secure sufficient transparency like glass. The change in contact angle characteristics due to grinding showed a tendency to slightly increase as the grinding time increased and the particle size of the sandpaper used was small, but the variation between samples was large and the average contact angle was 77~90°, showing no statistically significant difference. Surface treatment methods other than polishing were tried, and it was confirmed that it was possible to easily and simply improve the transparency by applying a commercially available vehicle scratch remover or silicone oil. In addition, a method for securing high transparency such as glass by using a scratch remover after sequential grinding while reducing the particle size of the sandpaper was proposed. Finally, even after surface treatment through polishing and various methods, it was difficult to secure a contact angle of 90° or more.