Anuar KASA, Zamri CHİK, Mohd Raihan TAHA

Global Stability and Settlement of Segmental Retaining Walls Reinforced with Geogrid

Most of segmental retaining wall design procedures such as NCMA, BS8006, AASHTO and NCHRP do not take into account global stability and foundation settlement in their design calculation. A system to solve the problem and to predict the stability of the wall quickly and accurately by using simple input was planned to be developed. This study used a residual soil that was classified as SC-SM according to the Unified Soil Classification System (USCS). Geogrid used in this study had a characteristic strength of 40 kN/m while concrete blocks had a minimum strength of 35 MPa. Simulations were performed using twodimensional FEM to calculate maximum deflection, maximum foundation settlement and maximum surface settlement. In addition, global stability was calculated by using phi/chi reduction method for each design. Prediction was done by using Response Surface Methodology. Mathematical models used for the RSM were MLR (Multiple Linear Regression), Pure Quadratic, Interactions and Full Quadratic. Among all the mathematical models in RSM, output of Full Quadratic was the closest to the target value

Keywords:

Prediction, Segmental retaining wall Geogrid, FEM, RSM,

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