My Research Interests 

Sachin Bakre

Home      PhD Thesis      Poster Presented      Experiments: IITB      Experiments: SERC      Experiments: Japan

Major 

Classification    Structural Dynamics

Earthquake Engineering

Finite Element Analysis

Random Vibrations

PhD 

Thesis               Response of Piping Systems with Supplemental Devices. [Submitted ]

I am working in the area of seismic control of structures (Piping in Nuclear and Industrial plants & Buildings) which involves study in all the major areas as mentioned above. The abstract of my work can be briefed as below:

Passive supplemental devices have been successfully implemented in vibrating systems to reduce structural response, primarily due to dynamic loads, but also for wind and earthquake loadings. In this technique, most of the input energy is concentrated into specially designed devices, rather than allowing it to develop in the primary structural elements, and thereby reducing damage in the main system. Hence, the application of this technique is widely adopted for piping systems, over active or hybrid passive control methods, for their simplicity in design, operation and maintenance. Researchers have proposed innovative supplemental devices for possible use in the piping systems. However, simplified analytical and systematic design procedures for optimal sizing and placement of these protective devices in piping systems are needed and not yet available. The main objective of this study is, therefore, to formulate a general framework for simplified analysis and optimal design of supplemental devices for seismic control applications. Here-in, the suitability of various supplemental devices is investigated under various excitations for controlling the mechanical vibrations and seismic responses of the piping systems; and also for increasing the inherent damping in the piping systems. The following six types of control systems have been examined in the study: (1) yielding metallic damper, (2) friction support, (3) viscous damper, (4) viscoelastic damper, (5) tuned mass damper and (6) multiple tuned mass dampers. Seismic response of typical piping systems equipped with each of the above dampers is investigated under parametric variation of important damper properties under narrow band random motions and few real earthquake ground motions. The analytical results thus obtained are compared for few sets of experimental results to establish the authenticity of the proposed procedures. Moreover, stochastic responses of the piping system incorporating linear damping devices like tuned mass damper and multiple tuned mass dampers is also investigated under white-noise random excitation, to further establish their effectiveness. Explicit expressions for the design parameters of the tuned mass damper are determined for the minimization of various response quantities of the piping system. In addition to this, analytical and design guidelines for designing piping systems with optimal dampers are also provided.

This work is fully supported by Board of Research in Nuclear Sciences (BRNS), Bhabha Atomic Research Center (BARC), Government of India.