한국도로학회논문집 제20권 제6호 (p.21-30)

다짐밀도 예측을 위한 구형입자를 활용한 DEM의 적용성 평가

Applicability Evaluation of DEM with Spherical Particles for Packing Degree Estimation
키워드 :
DEM,Packing Degree Estimation,Binary Mixture,Friction Coefficients

목차

ABSTRACT
1. 연구배경 및 목적
2. 다짐밀도 모형
  2.1. 골재 혼합물에 대한 다짐밀도 모형 특성
3. DEM을 이용한 골재 다짐 모사
  3.1. 진동 다짐밀도 실험 모사를 위한 해석조건
  3.2. 단일입도 입자더미의 다짐 모사 결과
  3.3. 혼합입도 입자더미의 다짐 모사 결과
  3.4. 다짐실험 모사 결과 및 비교
4. 결론 및 고찰
REFERENCES

초록

PURPOSES: In this paper, the packing degrees of binary granular mixtures under vibration compaction were simulated by using DEM with spherical particles to evaluate the applicability of the DEM for aggregate packing degree estimation.
METHODS: The packing degrees of fine particles, coarse particles, and their mixture with different fine particle fractions were evaluated in DEM simulation for given various material property conditions. In order to check the validity of estimated packing degrees of particle mixtures, analytical model such as Furnas model that is capable of considering wall effect and loosening effect.
RESULTS : DEM with spherical particles showed good agrement with analytical solution in terms of the packing degrees of binary granular mixtures with various fine particle fractions for most of conditions. Also, it was found that not the vibration amplitude but the ratio of particle diameter with vibration amplitude should be considered to explain the susceptibility of particle packing degree with vibration amplitude for the same acceleration condition and that the reduction in elastic modulus to shorten computational simulation time should be carefully considered when the packing degree is the most important concern.
CONCLUSIONS: It was concluded that DEM with spherical particles are good enough to estimate the packing degree of binary granular particles for most of conditions. However, the effect of inter-particle frictions between fine and coarse particles have to be studied further in order to clarify the issue relating poor predictions for high inter-particle friction conditions.