Design of geosynthetic-reinforced platforms spanning localized sinkholes

One of the techniques currently used to reinforce road and railway platforms in areas over localized sinkholes is reinforcement by geosynthetic sheet. To improve the existing analytical design method, new developments are proposed by taking into account in addition to the usual mechanisms, stretching of the geosynthetic sheet in the anchorage areas and the increase in stress on the edges of the cavity. Given that cavities can occur in any section of linear constructions, it was necessary to consider the continuous sections, which are the key determinant in selecting rigidity of the sheet, and overlapping sections, which are the major determinant in estimating surface settlement. An optimal overlap length was defined according to interface characteristics, cavity diameter and embankment height. A design chart was established for a particular case, showing the interest of the method suggested. The influence of the major geometrical and mechanical parameters was studied by means of a parametric study.