Experimental Study on the Performance and Improvement of a Frictional Damping Wall Using a Full Scale Steel Structure

Abstract eng:
A frictional damping wall, which consists of concrete blocks and reinforcing bars, was recently proposed. In this system each element is un-bonded for future reuse and stronger pre-stressed force is introduced in each layer of the wall than the top of the layers, where a connecting L-shaped steel plate to the upper beam will be placed and slide smoothly as the relative story drift between the lower and upper beams is generated. In the past studies, it was confirmed that friction is generated quite stably between the top blocks and the L-shaped steel plate even for large relative story drift. In this study, we verified the effectiveness of this wall on a five-storied full-scale experimental steel structure which was constructed at the Kyoto University Uji Campus. First, we conducted forced vibration tests in order to grasp the wall behavior during consecutive shaking and check the effectiveness of the friction damping system. Two damping walls are set on the east-west long-span direction of the full scale steel structure. We did the experiment twice, before and after the improvement in the damper sliding system. The purpose of the test is to know how much we will see the changes in the natural frequency when the prescribed prestress force are introduced to the damper. The introduced prestress force was 2kN per one bolt before the improvement, and was 3kN per one bolt after the improvement. The damping walls both before and after the improvement have 36 bolts in total. Next, we conducted static loading tests in order to grasp the wall behavior with large deformation. In this time, only a case on a damping wall after the improvement was performed because the case of the wall before the improvement had done. There is a three layered steel structure next to the five layered full-scale steel structure as a target. The static load test was performed through two hydraulic pressure jacks between three layered steel structure and the target full-scale steel structure, and we grasp the behavior on the concrete block frictional damping wall. The loading was performed at 3rd and 4th floors. The two pillars on the eastern side were loaded in the horizontal direction to the west. The maximum adding power of hydraulic pressure jack is 50 ton per one jack, so the total applied force was 100 ton. The applied prestress force was 4kN per one bolt. The total prestress force was changed by the numbers of bolts used, and the patterns of the total prestress forces are 0kN, 48kN, 96kN, and 144kN. Through the results of the static loading test, we measured the stiffness before and during frictional sliding and obtained sliding frictional forces when blocks and angle steel plates are sliding. Combining the results of the static loading test with the shear stiffness obtained from the result of preceeding study, we constructed a trilinear restoring force model for the wall. Finally, we conducted seismic response analysis in order to grasp the efficiency of the frictional damping wall.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket