A new layered shell model for reinforced concrete walls II: experimental validation against quasi-static tests

Nonlinear analysis procedures used in performance-based design/assessment of structural systems with reinforced concrete walls are subject to much improvement, upon implementation of a reliable modeling approach that is capable of accurately simulating the nonlinear response characteristics of both planar and non-planar walls at both global (force-displacement, moment-rotation, torque-twist) and local (e.g., strains, shear deformations, flexural deformations) response levels under combined and multi-directional loading conditions. Towards this objective, a novel nonlinear layered shell element, referred to as the Layered Fixed-Strut-Angle Finite Element (LFSAFE) model, was developed and implemented in OpenSees. In this paper, the effectiveness and accuracy of the LFSAFE model is experimentally-validated, via simulation of test results presented in the literature for non-planar (U-shaped and H-shaped) walls specimens subjected to quasi-static multi-directional lateral and torsional loading conditions. Model results obtained for U-shaped wall specimens under uni-directional lateral loading, bi-directional lateral loading, and pure torsion, as well as for H-shaped wall specimens tested under combined lateral and torsional loading, are systematically compared with test results to assess the capabilities of the model. Comprehensive response comparisons provided in this paper demonstrate that the LFSAFE model can accurately simulate salient response attributes of non-planar walls under combined loading, in terms of hysteretic load-displacement and torque-twist behavior, lateral load and torque capacity, stiffness, ductility, as well as contribution of flexural and shear deformations to lateral displacements and the vertical strain distributions developing both along the wall height and across the wall cross section.