الهام اندرخور

Given the widespread application of soil nailing for the stabilization of excavations and earth slopes in the recent decades, this research employed 42 three-dimensional numerical models of soil-nailed walls under seismic loading using the finite element method to eva‎luate their seismic performance in terms of permanent displacement of the wall crest and relative displacement of the wall after earthquake. Experimental and laboratory data from previous studies were used to validate a model and then the effects of various parameters on the seismic behavior of the wall such as nail length, spacing, and density in walls with 5 different heights of 6, 8, 10, 12 and 14 meters were investigated in three performance levels including serviceability limit state, ultimate limit state and failure of sandy soil. The seismic performance and flexibility of the nailed wall were eva‎luated by applying a loading pattern that simulated the characteristics of the 1990 Rudbar-Manjil earthquake recorded at Abbar station. This earthquake had a peak ground acceleration of 0.49 g and a predominant frequency of 8.33 Hz. The failure criterion of the walls with different heights was determined by varying the nail density and the normalized nail length, which is the ratio of the nail length to the wall height (L/H). The failure criterion in the models is the development of a continuous plastic shear zone that reaches the ground surface. The walls with heights of 6, 8, 12 and 14 meters failed at nail densities of 2.1, 2.8, 4.2 and 2.45 nails per square meter respectively with L/H ratio of 0.7 in all mentioned walls. The nail density in 10-meter walls at the time of failure was 1.25 nails per square meter with L/H ratio of 0.5. The results of this study indicate that the nail density factor is a significant parameter for the stability and deformation of nailed walls. However, this factor depends on the specific design of each wall and the ratio of L/H, which should be determined accordingly. Moreover, this study offered some guidelines for designing and optimizing soil-nailed systems under seismic conditions.

ديوار ميخكوبي شده , بارگذاري لرزه اي , مدلسازي عددي , روش اجزاء محدود (FEM) , تحليل مبتني بر عملكرد

Soil-nailed wall , Seismic loading , numerical modeling , Finite Element Method (FEM) , performance-based analysis

Elham Andarkhor

Dr. Bazyar