Search results for " seismic protection"
showing 4 items of 4 documents
Sequential design of multioverlapping controllers for structural vibration control of tall buildings under seismic excitation
2012
In this article, a computationally effective strategy to obtain multioverlapping controllers via the inclusion principle is applied to design a state-feedback multioverlapping linear-quadratic regulator controller for a 20-story building. The proposed semidecentralized controller only requires state information of neighboring stories to compute the corresponding control actions. This particular information exchange configuration allows introducing a dramatic reduction in the transmission range required for a wireless implementation of the communications system. More specifically, just a one-story transmission range is required by the proposed multioverlapping controller, while a full-buildi…
Experimental determination of viscous damper parameters in low velocity ranges
2017
In the last decades many strategies for seismic vulnerability mitigation of structures have been developed through analytical studies and experimental tests. Among these, energy dissipation by external devices assumes a great relevance for the relative design simplicity, even if applied to complex structures, and the effectiveness in reducing seismic demand. In particular, the use of fluid viscous dampers represents a very attractive solution because of their velocity-dependent behaviour and relatively low costs. The application on structures requires specific study under seismic excitation and a particular care of structural details. In this context the use of proper constitutive models fo…
Seismic response of steel frames with reduced beam sections
2003
This study concerns the effectiveness of weakening on the beams of fully and partially restrained connection steel frames in order to locate plastic hinges far from the joints. Two types of non-linear analysis, for geometry and constitutive law are developed: static pushover analysis, in which the structure is subjected to constant vertical loads and to horizontal loads linearly increasing up to collapse; and incremental dynamic analysis, in which the structure is subjected to uniformly scaled ground motions. Applications for four-bay frames with three and nine stories designed according to the EC3 code and for Italian 1st-category seismic areas are developed in order to evaluate the influe…
Passive Control of Linear Structures Equipped with non-Linear Viscous Dampers and Amplification Mechanism
2008
Fluid damper devices in civil structures such as buildings or bridges are commonly used as energy absorbers for seismic protection. The problem in the response analysis of structures with filled dampers mainly consists in the fact that, due to the strongly nonlinear behavior of such equipments, the response spectrum technique fails. Moreover, in order to enhance the damping effect various toggle brace configurations have been recently proposed. In this paper by using the concept of power spectral density function compatible with the elastic response spectrum and the stochastic linearization technique, the equivalent damping ratio is obtained. It is shown that once the system is linearized r…