Effect of bending stiffness of geotextiles on bearing capacity improvement of soft clay

In the previous papers, the authors have investigated the factors contributing to bearing capacity improvement of soft clay reinforced with geotextiles through the results from laboratory model tests. It was emphasized that the frictional characteristics exerted between clay and geotextile is most important for improvement of bearing capacity. However, it has not been made clear how the bending stiffness of geotextiles is correlated to bearing capacity improvement. In the present paper, therefore, the results from laboratory investigation into the effect of bending stiffness are discussed. The following Conclusions are derived from the present study : (1) the bending stiffness of combined geotextiles with sand mat covering the soft ground which were determined directly by back-analysing the results from laboratory model tests is closely related to improvement of bearing capacity in soft clay. This back-calculation is based on the assumption that the combined sand mat with geotextiles on soft ground is considered the simple beam with partially distributed uniform loads supported bythe elastic body and (2) the effect of sand mat overlaid on soft clay on bearing Capacityimprovementis most exerted in the Combinationwith geogrid. In this case, increase in bearing capacity is largely contributed by increase in bending stiffness of geogrid combined with sand mat.