Studies have shown that the interface transmissivity between a geomembrane (GMB) and geosynthetic clay liner (GCL) is scale dependent and decreases with the wetted distance away from a hole in the geomembrane or hole in a wrinkle in the geomembrane. This has significance with respect to the leakage that can be expected, particularly at lower stress situations such as in covers and ponds. Based on the measured transmissivity in a series of tests conducted at different stress levels, the variability in transmissivity in tests for a contact area of 180 cm^2 provides statistical data defining the distribution of the transmissivity resulting from subtle variations in contact conditions at different stress levels. This paper examines the implications of this variability with respect to the leakage through a hole in a wrinkle in the geomembrane over a geosynthetic clay liner considering the effects of stress. It is shown that at overburden stresses of 10 and 25 kPa, when one considers the statistical distribution of transmissivity over a range of four orders of magnitude for an area of 180 cm^2 together with continuity of flow, then one can explain the observed decrease in transmissivity at a larger scale. Based on this, the effects on potential leakage through composite liners in mine waste covers and leakages from storage lagoons are reported.

Structures reinforced with geosynthetics consist in increasing the mechanical performance of a soil (mainly shear resistance) by associating it with flexible geosynthetics inclusions. One of the important issues in the construction of geosynthetic reinforced walls is the supply of natural backfill materials with the required properties needed for the stability of the wall. Indeed, unlike geosynthetics that exhibit stable properties due to extensive quality controls during the manufacturing process, soil matrix will vary from a site to another and even from the beginning to the end of the excavation work. It influences the soil stability itself and also the soil-geosynthetic interface.
As it minimizes the influence of soil characteristics on the stability of the reinforced structure, M3S geotextile geocells make possible, in addition to the construction of reinforced structures with complex shapes, to reuse the soil material excavated on-site to build the wall, including those with very poor geotechnical characteristics.
This publication presents the M3S cellular system and its mechanical and functional characteristics. It also gives the main design steps to consider and the limits of the system.
Finally, examples of realization will be given with their associated environmental and social footprint reductions due to the use of onsite materials and the reduction of traffic.

Design and construction of a geogrid stabilized working platform for use with a ringer crane to construct a petrochemical facility in the southern US was undertaken in 2016 and completed in 2017. The PTC-200 DS ringer crane was configured with a maximum bearing pressure of 192 kPa, a load spreader ring with outside and inside diameters 53 m and 33.2 m, respectively, and was rated the third largest ringer crane in the world. Stringent criteria for differential and total settlement needed to be met to ensure successful operation of the crane. Site soil conditions exhibited predominantly fat clays, oftentimes slickensided, and the occasional presence of sandy silt lenses and pockets. Original plans for the crane bearing pad were to construct a deep foundation system composed of two hundred 457-mm square concrete piles and a 61-m diameter concrete pile cap. Alternatively, a geogrid stabilized working platform was designed to improve allowable bearing capacity of the soil and to decrease potential settlement while ultimately being less expensive than a concrete deep foundation system. Estimated settlement was based on a pseudo rectangular section of the annulus area and analyses were performed at four locations, center, corner, midpoint of short side, and midpoint of long side of the rectangular section. The geogrid mechanically stabilized working platform designed and constructed was 1829 mm thick and composed of five layers of multi-axial geogrid and crushed angular graded aggregate material. Estimated total cost savings of $3.1 million included savings from reusing the crushed stone at other site locations compared to the concrete foundation alternative and completing the project 32 days ahead of schedule. The success of the geogrid stabilized platform was further demonstrated when it withstood Hurricane Harvey in August 2017 without damage and the crane was back in operation the day after the storm passed.