Behavior of reinforced concrete walls with integrated tubing system

A novel tuned liquid wall damper (TLWD) system was developed by incorporating liquid-filled tubes within concrete walls to improve structural performance versus motion. However, the placement of the hollow tubes within a concrete wall introduces voids, and their effect on the general structural performance of the multifunctional concrete structure is not well understood. The objective of this paper is to further the understanding of reinforced concrete walls equipped with such tubing systems. To this end, experimental testing was performed on three pairs of reinforced concrete walls with circular openings. One pair was tested for four-point bending, one for axial compression, and the other for pushover. Cracking, failure load, and failure mode were monitored during testing. Finite element (FE) models were developed and correlated with testing results, and results numerically compared against conventional, solid concrete walls also through FE modeling. Results showed that concrete walls with circular opening performed similarly to solid walls for strength, whereas the reduction in strength caused by the tubes did not have significant adverse effects. The strength reduction of the RC wall panel with integrated tubing system is dependent on the configuration of integrated tubing system and the loading condition such as bending moment, axial compression, and in-plane shear. Finally, the strengths of the walls with openings were calculated following ACI Code, which were compared with those from the test. Overall, results showed that a tuned liquid column damping system can be integrated within a concrete wall to create a TLWD, with the wall preserving its structural function.