Numerical and Larg-Scale Laboratory Study of Rock Column Groups in Sandy Soil Behavior Improvement

Abstract

The use of stone columns as one of the effective methods in improving soil behavior can increase soil bearing capacity. One of the common methods in improving poor soil is the use of stone columns. Stone columns are considered one of the suitable options to improve the bearing capacity of loose cohesive and granular soils, which, in addition to reducing soil subsidence, is also considered an effective, economical, and environmentally friendly method in structures built on soil. Considering the financial and human losses caused by the construction of various buildings on poor soils, the importance of developing improvement methods in weak and unsuitable soils is essential. On the other hand, sandy soils are always considered an unsuitable soil sample in design. Therefore, in the present study, we use group stone columns to improve the behavior of a sandy soil sample. When a sample of soft sandy soil is exposed to loading due to its sandiness, we see an increase in soil subsidence and thus a decrease in its load-bearing capacity. In order to obtain practical and useable results in practice, in addition to numerical studies, we conduct a laboratory study to investigate the effect of rock columns on improving sandy soil performance. In sandy soil armed with 4 rock columns, the comparison of the results obtained from the numerical and laboratory model to the displacement of 2 mm is completely consistent with each other, and with increasing displacement, we see a difference between the numerical and laboratory results, so that for a 6 mm displacement, we see an 8% difference in numerical and laboratory results. The final sample capacity in the numerical and laboratory study in this case is 6730 N and 6192 N, respectively.