Pushover experiment and numerical analyses on CFRP-retrofit concrete shear walls with different aspect ratios

The efficiency of shear walls to sustain the earthquake loads mainly depends on the aspect ratio, the vertical load, and the ratios of longitudinal and transverse reinforcement. In this paper, two lightly reinforced concrete walls have been experimentally and numerically investigate with an aspect ratio equal to 0.67 (short wall) and 2.5 (slender wall). Different retrofitting strategies have been considered using Carbon-Fiber-Reinforced-Polymer (CFRP) materials. Pushover analyses have been carried out using two advanced numerical approaches for the concrete modeling: the first one adopts a 2D plane stress approach with a local concrete model based on the smeared fixed crack approach and a classical regularization technique based on the fracture energy; the second investigates a coupled elastoplastic damage model using local approach in 2D and 3D simulations. The numerical results in terms of the load–displacements are very consistent with experimental data. The observed failure modes and crack patterns are satisfactorily reproduced for both walls, without or with the CFRP strengthening.