Document Type : Research Paper

Authors

Civil Engineering Department, University of Technology, Baghdad, Iraq.

Abstract

The objective of the present study is to understand the behavior of soft soil strengthened by stone columns under dynamic seismic load. Ordinary and encased stone columns were used under different conditions. The present study converges around the dynamic response of stone columns of lateral shaking, the interaction of soil frame for understanding settlement mechanisms and the prediction of dynamic load limitations of foundations in soft soils subjected to seismic load (during vibrations).  The results of this research will provide the basis for assessing measures to reduce the severity of seismic hazards and the seismic design of foundation structures in soft soils. As a result, soil models will be tested on the shaking table to make seismic ground vibration under several conditions (frequencies, undrained shear strength of soft soil, for stone columns type both ordinary and encased stone columns). It was concluded that the values of horizontal displacement increase by increasing the loading frequency, as well as the horizontal displacement is faster and greater at 2 Hz than 0.5 and 1 Hz in all cases. The rate of horizontal displacement increases in models on the soil of undrained shear strength cu= 15 kPa is greater than that in undrained shear strength cu= 25 kPa because increasing the strength of the soft soil leads to greater resistance to deformation and a decrease in the level of horizontal displacement.

Highlights

  • Ordinary and geogrid encased stone columns were used under different conditions.
  • Shaking table was manufactured to simulate earthquake loading.
  • Dynamic response of stone columns to lateral shaking.
  • The values of horizontal displacement increase by increasing the loading frequency.
  • The rate of horizontal displacement increases with soil undrained shear strength.

Keywords

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