Experimental and numerical investigation of jointed self-centering concrete walls with friction connectors

A jointed self-centering (SC) concrete wall system with friction connectors is proposed, in which the precast concrete wall panels are assembled through unbonded posttensioning (PT) tendons to provide self-centering capacity, and friction connectors at the vertical joint provide supplementary energy dissipation as the walls move relatively to each other during a major earthquake. The wall toes are protected by the steel jackets from crushing as the walls rock. The behavior of the jointed wall system was experimentally investigated through nine cyclic load tests, based on which the influence of different initial PT forces and friction forces on structural performance of the walls was discussed. Besides, strains on the steel jackets during the tests were measured to validate the effectiveness of steel jackets, and three-dimensional laser scanning technique was applied to measure the in-plane and out-of-plane deformations of the walls. It is observed that the main structure remained resilient after the nine tests with the maximum drift ratio of about 2.98%, though cracking in concrete cover at the eastern connectors was found after a number of reversal loading, which calls for improved structural details. A numerical simulation method of the jointed SC wall system is proposed, and the simulated hysteretic behaviors match well with the test results.