Bearing Capacity Mechanism of Geocell Reinforced Soil Foundations

The technology for restoring a damaged road system is critical for reaching victims and reconstructing damaged areas in large-scale natural disasters caused by earthquake and tsunami. Soil reinforcement technology with geocell materials can be useful in the above situation. This technology has been applied to road construction on soft soil ground, and its usefulness has been recognized. However, its reinforcement mechanism has not been investigated adequately. The current design method for geocell mattress under vertical load is based on classical pavement engineering and not on the actual mechanism of geocell reinforcement. Further technical investigation is required to achieve the rational design and construction of geocell mattress. The authors have developed a visualization technique for geocell mattress by using particle image velocimetry (PIV) analysis. The results obtained in the current stage are as follows: (1) mixing of colored sand with laboratory fill material is useful in visualizing the bearing capacity model test with PIV analysis. This paper proposes a method to determine the mixing ratio of two types of sand by conducting basic calibration tests. (2) This method can be used to visualize the behavior of soil confined by the geocell through a laboratory model test. This paper reports the results of the visualization.