동결 온도에서 다짐효과에 관한 실험적 연구

국문 초록 (Abstract)

우리나라는 사계절이 뚜렷하며 여름에는 고온다습한 무더운 날씨를 보이고 겨울에는 혹한의 날씨가 지속된다. 이러한 계절적 특성을 고려하여 국내 토공 분야에서는 많은 연구들이 있었으나 대부분의 연구가 지반의 동결.융해에 초점을 맞추어 이루어졌다. 이러한 연구들은 시공 당시의 기온에 따른 지반특성을 반영하지 못하였으며 상온에서 다져진 지반을 대상으로 실시되었다. 그러나 동절기 다짐의 경우 상온에서의 다짐과는 다른 지반상태를 나타낼 것으로 예상되며, 그에 따른 동결.융해로 인한 강도 및 변형특성 또한 다르게 나타날 것으로 판단되나 이를 고려한 연구는 아직까지 전무한 상황이다. 따라서 본 연구에서는 -3℃와 -8℃에서 주문진 표준사에 카올리나이트를 0%, 5%, 10%, 15%의 중량비로 혼합하여 다짐시험을 실시하였으며, 상온(18℃)에서의 다짐곡선과 비교하여 온도 및 세립분 함량에 따른 다짐 효과를 살펴보았다. 시험 결과, 동결 온도에서 다짐 시 최대건조단위중량이 감소하는 경향을 보였으며, -8℃ 이하에서 다짐 시공 시 시방서의 다짐기준을 만족하지 못하는 것으로 나타났다.

다국어 초록 (Multilingual Abstract)

Korea has four distinct seasons, showing hot and humidity in summer and cold weather lasted in winter. Domestic research on earth work has been developed according to the seasonal characteristics, and most of research topics have focused on the effect of freezing-thawing on the performance of geo-materials. However, the previous research was performed on the ground compacted at room temperature and therefore, the effect of the sub-zero temperature at the time of construction was not fully investigated. The ground characteristics compacted at freezing temperature can be different from those at room temperature and show different characteristics of strength and deformation caused by freezing and thawing. Therefore, the compaction tests on sandy materials were conducted under various temperature at -3℃ and -8℃ with various fine contents of 0%, 5%, 10% and 15% in weight fraction. The effectiveness of soil compaction at below-freezing temperatures were compared with the compaction at room temperature at 18℃ in terms of the maximum dry unit weight and optimum water contents. Based on the test results, the maximum dry unit weight tends to decrease with the freezing temperature and the relative compaction at -8℃ can not be satisfied with general specification standard.

목차 (Table of Contents)

• ABSTRACT
• 요지
• 1. 서론
• 2. 동결 온도에서 다짐
• 3. 시험 방법
• 4. 시험 결과 및 분석
• 5. 결론
• References

참고문헌 (Reference)

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