Abstract
In order to evaluate effects of spatial variability of ground improvement on the seismic behavior of improved ground, a series of shaking table tests in 1g gravitational field has been carried out through investigating the seismic behavior of partially improved ground. Following conclusions were obtained: (1) The increase in excess pore water pressure was restrained by the existence of improved element around un-improved element. From the test result in this study, it is suggested that the excess pore water pressure in un-improved area can be greatly reduced as long as 60% of ground is rightly improved enough not to cause liquefaction. (2) Average vertical ground displacement after seismic loading can be greatly reduced, which suggested that partial existence of un-improved area in improved ground is allowable for practical liquefaction countermeasure. (3) An additional effect for reducing ground settlement by the improved element is considered based on the percolation theory.
