Instability Analysis of Eccentrically Loaded Concrete Walls

In this paper, a computer‐based numerical technique for the prediction of the instability load/length of concrete walls is developed. The wall is treated as a beam‐column and is generally subjected to axial force and two end moments. A wall strip is treated here as a plane‐strain problem. Any material models of concrete exhibiting different behaviors in compression and in tension can be implemented in this analysis procedure. The load‐deflection curves with both the ascending and descending branches are predicted by a new numerical technique based essentially on the Newmark method combined with the concept of equivalent column for computing the instability load of the beam‐column. It is found that for concrete walls within the usual slenderness ratios, material failure prevails and their load‐carrying capacities are very sensitive to a small change in end eccentricities.