Properties of geogrid-reinforced-marine-slope due to the groundwater level changes

Evaluation of slope stability, especially in the absence of a proper bed such as marine soils, is one of the most important issues in geotechnical engineering. Using geogrid layers to enhance the strength and stability of embankments is regarded as a commendable stabilization method. On the other hand, groundwater level erratically fluctuates in coastal areas. Therefore, the aim of this research is to study effects of groundwater level changes on the stability of a geogrid-reinforced-slope on loose marine soils in the Qeshm Island, Iran. At first, geotechnical properties of the site were obtained by a comprehensive series of geotechnical laboratory and in-situ tests. Then, by simultaneous changes of groundwater level and several parameters such as embankment slope, loading, geogrid layer length, geogrid layer number, and tensile strength of geogrid layers, different characteristics such as embankment safety factor (SF), vertical and horizontal displacements at embankment top and embankment base were studied. It is observed that groundwater level has significant effects on the behavior of the embankment. For most of the observations, by decreasing the groundwater level, the displacements decreased and consequently safety factor increases. Increasing the length, number, and tensile strength of geogrid led to the reduction of the displacements and the increment of the safety factor.