EXPERIMENTAL STUDY OF A RECYCLED PROTOTYPE OF A REAL SCALE FLUID VISCOUS DAMPER

Taipicuri Y.; Zavala C.; Nuñez L. · World Conference on Earthquake Engineering proceedings (2021)

Resumen

In Peru, severe past earthquakes have demonstrated that the majority of buildings did not collapse, but they would be severely damaged, as a consequence, their continuous functionality is affected, and the reparation cost is increased. Seismic protection systems are a good alternative to reduce structural damage by using various mechanisms such as seismic isolation or passive dampers. However, in Peru, there is a limited number of buildings with that kind of mechanism; nowadays, the seismic performance of new or retrofitted buildings with fluid viscous dampers is frequently analyzed through numerical simulations with data provided by the importing company of this device, indeed, there are not Peruvian fluid dampers. Furthermore, there is an informal market in Lima of pieces from disused or damaged construction machinery, which are sold like scrap metal. For these reasons, this research aims to develop at the structural laboratory of the Japan-Peru Center for Earthquake Engineering Research and Disaster Mitigation -CISMID a prototype of a fluid viscous damper to understand and estimate its dynamic behavior. To do so, a recycled hydraulic steel tube of a bulldozer was modified to manufacture the device in order to produce an environmentally friendly prototype with an acceptable behavior. Moreover, this prototype was manufactured by reducing complex processes of manufacturing to decree the construction costs because it has only an annular gap of 0. 5mm between the piston and the cylinder. A quasi-static cyclic loading test is performed to determine the properties of the prototype such as the hysteretic behavior, the effective damping ratio, and the damping coefficient of its linear behavior because the experiment is performed with low velocities. First, three specimens of two chambers were tested using glycerin as the hydraulic liquid; the piston was subjected to a sinusoidal displacement with an amplitude of ± 100 mm of stroke. Then, the prototype was modified to have one more chamber to contain nitrogen gas, also the hydraulic liquid was changed to silicon. Besides, the new amplitude of the sinusoidal displacement is ± 50 mm. Then, based on the data from the experiments, numerical models are proposed to describe the hysteretic behavior of the two types of prototypes. Finally, these prototypes are evaluated in a spring-mass model of one degree of freedom (SDOF) of a steel frame with these devices to perform a time history analysis to evaluate and compare the structural dynamic response. © The 17th World Conference on Earthquake Engineering.

Instituciones: Universidad Nacional de Ingeniería