Publication Abstract

Proceedings of the Deep Mixing 2015 Conference, (DFI)

Development of Fiber-Reinforced Soil Improvement Using CSM Method
Takao Koono, Takenaka Corporation, Japan; Toshio Yonezawa, Takenaka Corporation, Japan; Masamichi Aoki, Takenaka Corporation, Japan; Franz-Werner Gerressen, BAUER Maschinen GmbH, Germany; Helmut Florian, Bauer Maschinen GmbH, Germany; Herbert Kuh, BAUER Maschinen GmbH, Germany

To increase the bearing capacity of the ground, soil improvement technique is often adopted. One advantage of soil improvement techniques is the fact, that the impact to the environment is low, as the system utilizes the existing soil. Recently, compressive strength of soil improvement gets more into the focus for the use of building foundation. To prevent brittle fracture, which is a weak point of soil improvement, fiber reinforced soil improvement has been developed. Laboratory tests were conducted to examine the fibers suitable for reinforced soil improvement, and examine the optimum mix design for fiber cement slurry. Based on the laboratory tests, polypropylene fiber and cellulosic viscosity admixture was selected. For the laboratory tests a scaled model of CSM mixing head was used to examine the dispersion of the fibers in the ground. Using the CSM mixing head, the outer periphery fibers of soil improvement seemed to be arranged in the vertical direction, toughness performance of the soil improvement could be improved. Furthermore, full scale field test was performed using actual CSM unit, modified to enable the use of fiber mixed slurry. The validity of the material as well as the toughness performance of the soil improvement, determined from lab test results, was confirmed. In addition, it was confirmed that fiber reinforced soil improvement can be constructed appropriately by CSM method.

 article #2110; publication #1013 (DM-2015)