Analytical Investigation of Effect of Vertical Drains to Consolidation Settlement Process in Isotropic Soils

Document Type : Research Paper


shahid chamran univercity of ahwaz


     Vertical drains installation can be used to accelerate the consolidation settlement. In this research, three dimension equation of consolidation in cylindrical coordinate with certain boundary condition was obtained and the analytical solution was performed. Then, the results at the MATLAB were written and the variation of degree of the settlement versus time was investigated. The results with experimental data of odoemeter test were also compared. The account of radial drains in this model were considered 0.5, 1, 1.5 and 2 cm. To verify the analytical solution, in the isotropic soils and zero radius of the vertical drain, the results and the traditional Terzaghi’s method were fully established with suitable satisfactory. The results showed. The most difference of 100% settlement velocity between of Terzaghi method and radial-vertical method was related to 40kg loads at the drain’s with 2 cm radius. This amount was 6 hr, however, the least of difference time of 100% settlement velocity was related to 5 kg loads at the drains with 0.5 cm radius and this time is 1 hr. However, results showed the analytical solution in comparison to numerical methods are predicted less time of average degree of consolidation as more accuracy.


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Volume 40, 1-1
Special Issue
June 2017
Pages 61-72
  • Receive Date: 15 November 2014
  • Revise Date: 07 June 2017
  • Accept Date: 10 February 2016
  • Publish Date: 01 January 1970