rectangular and cylindrical tlds with rotatable baffles to improve seismic behavior of structures, a numerical study

One of structural passive control methods is to use tuned liquid damper (tld). however, because of the nature of the tld, only one tuning frequency can be created when the water is sloshing. to fix this problem, some installed rotatable baffles can be embedded inside tld called variably baffled tld (vbtld) where by changing the angle of the baffles a tuning frequency range is created. this gives the passive control system the capability to be pre-tuned according to the desired frequency. in this paper, the effects of rectangular and cylindrical shapes of container on behavior of vbtld are studied and numerically validated with experimental results. there are four baffles inside each damper tuned manually in different cases. in numerical investigation, the rectangular tld created greater returning force than cylindrical tld in all depth and angle selections. by increasing the baffle angle, from 0 ° to 80 ° at the water depths of 4, 5.2 and 6.4 cm, the control forces are increased 59.8%, 38.4% and 30.2% respectively for rectangular tld and 58.4%, 50.4% and 46.1% for cylindrical tld.