مشخصات پژوهش

In this study, excavation walls stablized by both grouted nail and a new type of screw nail with helix plates and treaded shaft were modelled and the results were compared. The effects of surcharge load and wall height on the screw and grouted nails performance were investigated. The results showed that the settlement profile of the ground surface within the excavated wall has the same shape for different values of slope height, and consists of two main parts, critical and non-critical parts. The length of the critical zone is 0.60-0.7 times of the slope height and the rate of changes of the surface settlement in critical part is greater than the other one. The rate of increase of surface settlement and the maximum settlement of the ground surface at the edge of the reinforced wall by screw nails and grouted nails have the same values in clayey soils. There is not significant difference in safety factor of slope and the vertical and horizontal displacemens of the reinforced wall by screw and grouted nails in clayey soils. It can be concluded that, there is not considerable difference between the performance of the screw and grouted nails in clayey soils.