This is a ground improvement method suitable for liquefaction countermeasures, achieved through extensive infiltration and rapid construction of large-volume soil. The consolidation over 19 years has been demonstrated through large-scale outdoor injection tests!
The "Permanent Grout Injection Method" is one of the chemical injection methods. The purpose of improving this method is for permanent improvement, but in recent years, its application range has also expanded as an injection method for temporary improvement. The injection material used is "Permanent Grout," which has been theoretically and empirically validated for permanence, and the injection form is designed to be permeation injection that does not disturb the sedimentary state (skeletal structure) of the ground, with the principle of uniformly improving the ground.
The "Expakka Method" involves attaching bag bodies (geo-bags) at intervals to the injection outer pipe, inflating these bag bodies to anchor them in the ground and form soil packers, which enables permeation injection by injecting from a large space, allowing for rapid improvement over a wide area. The Expakka Method series includes Expakka-N Method, Expakka NEO Method, 3D-EX (Expakka) Method, and Expakka Lotus Route Method.
[Demonstration of Long-Term Durability Over 19 Years Through Large-Scale Field Injection Tests] The results of demonstration tests on permeation solidification and aging solidification through large-scale field injection tests combining Permanent Grout (injection material) and injection methods (such as the Expakka Method) have been evaluated, and the method received the 2002 Technical Development Award from the Japanese Geotechnical Society (Yonekura, Shimada).
