en Research Paper Research Paper <font size="1" face="Times-Italic"><font size="1" face="Times-Italic"><p align="left">In the present investigation, the cyclic load deformation behaviour of soil-fly ash layered system is</p><p align="left">studied using different intensities of failure load (I = 25%, 50% and 75%) with varying number of cycles (N =</p><p align="left">10, 50 and 100). An attempt has been made to establish the use of fly ash as a fill material for embankments of</p><p align="left">Highways and Railways and to examine the effect of cyclic loading on the layered samples of soil and fly ash.</p><p align="left">The number of cycles, confining pressures and the intensity of loads at which loading unloading has been</p><p align="left">performed were varied. The resilient modulus, permanent strain and cyclic strength factor are evaluated from</p><p align="left">the test results and compared to show their variation with varying stress levels. The nature of stress-strain</p><p align="left">relationship is initially linear for low stress levels and then turns non-linear for high stress levels. The test</p><p align="left">results reveal two types of failure mechanisms that demonstrate the dependency of consolidated undrained</p><p align="left">shear strength tests of soil-fly ash matrix on the interface characteristics of the layered soils under cyclic</p><p align="left">loading conditions. Data trends indicate greater stability of layered samples of soil-fly ash matrix in terms of</p><p align="left">failure load (i) at higher number of loading-unloading cycles, performed at lower intensity of deviatoric stress,</p><p align="left">and (ii) at lower number of cycles but at higher intensity of deviatoric stress.</p></font></font> Layered soils, cyclic loading, triaxial tests, fly ash, shear strength 73 89 http://ijce.iust.ac.ir/browse.php?a_code=A-10-3-146&slc_lang=en&sid=1 M.A. Khan 18003194753284600419 18003194753284600419 No A. Usmani 18003194753284600420 18003194753284600420 No S.S. Shah 18003194753284600421 18003194753284600421 No H. Abbas abbas_husain@hotmail.com 18003194753284600422 18003194753284600422 Yes