# The Seepage and Soil Plug Formation in Suction Caisons in Sand Using Visual Tests
## 4 Conclusions  
A series of model tests were conducted in this study to investigate the visualization of suction caisson penetration in sand. The following conclusions can be drawn:  
1. The seepage field can be visualized while the carmine stain flows along a streamline in the soil around the suction caisson. The seepage velocity is larger as the streamline moves toward the wall of the suction caissons. The pre-test results show that the seepage failure took place in the sand when the suction in the caisson with buried depths of 5, 10, and 15 cm was greater than 2.0, 3.5, and 4.0 kPa, respectively. The results indicated that the seepage path of the soil is unrelated  
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