The use of geotextile reinforcement for ground improvement is discussed. Two mechanisms of geotextile reinforcement for ground improvement are presented. The first mechanism is activated at relatively small vertical deformations of the foundation. The second mechanism, commonly referred to as tensioned membrane effect, comes into play when large differential deformations of the foundation occur. Fundamental to design, the geotextile is required to carry tensile load, within a defined strain limit, over the design life of the structure. Partial factors of safety are applied to derive the allowable design strength for the geotextile. The relevant partial factors include those applied to creep, installation damage and environmental effects. The importance of geotextile laying direction is discussed. On-site seaming methods and guidance on achievable seam strengths are presented. Two case studies are described. The first case study at Cape Preston, Australia, involved the use of high strength woven polyester geotextile to reinforce a 7 m high embankment constructed over soft estuarial mud and was subject to intensive induced loading. This case study illustrated the activation of predominantly the first mechanism of geotextile reinforcement. The second case study involved the use of high strength woven polyester geotextile to reinforce a soil capping layer over an extremely soft wastewater sludge pond in Harbin, China. This case study illustrated the activation of the second mechanism of geotextile reinforcement.
Menu