Original Article
Abstract
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Purpose: In this paper, an experimental study was conducted to analyze the difference in shear strength caused by the problem of excluding coarse particles due to the size of the test specimen in the direct shear test. Method: A large-scale direct shear test was conducted on three weathered soils containing coarse aggregates with a maximum diameter of 50mm. In addition, a small-scale direct shear test was performed using a sample with a maximum diameter of 5 mm, excluding coarse aggregates. Result: In the case of the small-scale direct shear test, compared to the results of the large-scale direct shear test containing large particles, the internal friction angle was about 2.3% smaller, and there was no significant difference. In terms of cohesion, compared to the large-scale direct shear test, the small-scale direct shear test derived about 80.3% smaller value, showing a relatively large difference. Conclusion: In the large-scale direct shear test, it was analyzed that the coarse particles had a greater impact on the cohesion than the internal friction angle. Therefore, granite weathered clay containing coarse particles is judged to have the same shear strength as the cohesive force that is not affected by vertical stress. In this study, it was analyzed that the small-scale direct shear test, which excludes the coarse particles that are commonly used, provides results on the safety side by excluding the effect of coarse particles.
연구목적: 본 논문에서는 직접전단시험에서 시험시편의 규모 때문에 부득이 굵은 입자가 제외되는 문제 때문에 발생되는 전단강도의 차이를 분석하고자 직접전단시험을 실시하는 실험연구를 수행하였다. 연구방법: 최대직경 50mm의 굵은 골재가 포함된 3개의 풍화토를 대상으로 대형직접전단시험을 실시하였다. 또한 굵은 골재가 제외된 최대직경 5mm 시료를 이용하여 소형직접전단시험을 실시하였다. 연구결과: 소형직접전단시험의 경우 큰입자가 포함된 대형직접전단시험의 결과에 비하여 내부마찰각은 약2.3% 작은 값을 도출하여 비교적 큰 차이가 없었다. 점착력에서는 대형직접전단시험에 비하여 소형직접전단시험이 약 80.3% 작은 값을 도출하여 비교적 큰 차이를 나타내었다. 결론: 대형직접전단시험에서 굵은 입자가 내부마찰각보다는 점착력에 큰 영향을 준 것으로 분석되었다. 따라서, 굵은 입자를 포함한 화강풍화토는 수직응력에 영향을 받지 않는 점착력과 같은 전단강도를 갖고 있는 것으로 판단된다. 본 연구에서는 일반적으로 사용되고 있는 굵은 입자를 제외한 소형직접전단시험은 굵은 입자의 효과를 제외함으로서 안전측의 결과를 제공하는 것으로 분석되었다.
- Hong, Y.H., Byen, Y.H., Chai, J.G., Lee, J.S. (2015). "Shear behavior of sand samples according to the type of shear box in the direct shear test." Journal of Korean Geotechnical Society, Vol. 31, No. 3, pp. 51-52. 10.7843/kgs.2015.31.3.51
- Jewell, R.A. (1989). "Direct shear test on sand." Geotechnique, Vol. 39, No. 2, pp. 309-322. 10.1680/geot.1989.39.2.309
- Ju, J.W., Park, C.S., Choi, H.-N. (1998). "Triaxial test of Jumunjin standard sand according to relative density." Korean Society of Civil Engineers Conference, Vol. 2, pp. 73-76.
- Kim, J.G., Choi, Y.H., Jung, J.Y., Kang, K.S. (2000). "Study on shear constants of jumunjin standard sand according to direct shear test type." Korean Society of Civil Engineers Conference, Vol. 2, pp. 439-442.
- Kim, J.S. (2020). "An experimental study on the engineering characteristics analysis of unsaturated weathered granite soil." Journal of Korea Society of Disaster Information, Vol. 16, No. 3, pp. 577-585.
- Kim, J.S., Kim, J.H. (2019). "Scale effects of the specimen on shear strength of sand by direct shear test." Journal of Korea Society of Disaster Information, Vol. 15, No. 4, pp. 590-596.
- ks F2343 (2022). The Method for Direct Shear Test of Soil Under Consoildated Drained Conditions. Korean Agency for Technology and Standards.
- Lee, S.D. (2017). Soil Mechanics. Gumi Library, Seoul, Korea, pp. 239-295.
- Publisher :The Korean Society of Disaster Information
- Publisher(Ko) :한국재난정보학회
- Journal Title :Journal of the Society of Disaster Information
- Journal Title(Ko) :한국재난정보학회논문집
- Volume : 20
- No :1
- Pages :169-176
- DOI :https://doi.org/10.15683/kosdi.2024.3.31.169
Journal of the Society of Disaster Information
