MONOTONIC AND CYCLIC LOAD TESTING OF PARTIALLY AND FULLY ANCHORED WOOD-FRAME SHEAR WALLS

The objectives of this study were to evaluate the performance of wood-frame shear walls under monotonic and cyclic loads by: 1) determining variability of shear wall performance; 2) comparing performance of walls under each loading protocol; 3) evaluating effects of anchorage on wall perfor- mance; and 4) evaluating performance of walls qualitatively and quantitatively with respect to code- defined performance measures. Sets of tests consisting of eight partially and two fully anchored walls were conducted using both the ASTM E564 monotonic protocol and CUREE cyclic-test protocol for ordinary ground motions for a total of 20 walls. Statistical comparisons of parameter variance and mean values were made between partially anchored walls tested under different protocols and performance comparisons were made between partially and fully anchored walls. Cyclic tests on partially anchored walls generally exhibited a coefficient of variation that was lower than for monotonic tests. Failure mode of fully anchored walls was different than that for partially anchored walls because hold-downs changed the load path. Comparison of test results with ASCE 41 m-factors suggests that ductility of partially anchored walls is below the acceptance criteria for shear walls with structural panel sheathing.