scholarly journals Seismic Analysis and Design of Multi Storey RC Buildings with and without Fluid Viscous Dampers

Author(s):  
Prof. Sanjay Bhadke

Earthquakes are one among the foremost destructive of natural hazards. Earthquake occurs due to sudden transition motion of the ground as a result of release of energy in a matter of few seconds. This recent events remind us of the vulnerability of our society to natural hazards. The protection of civil structures, including material content and human occupants is, doubtless, a worldwide priority. The challenge of structural engineers is to raised withstand these natural hazards. In the present study reinforced concrete moment resisting frame building of G+20 are considered. The building is taken into account to be located in the seismic zone (v) and intended for commercial purpose. Model-I Building without dampers, Model-II –Building with dampers. The building of G+20 has been modeled by providing with and without damper providing all parameters using S A P 2 0 0 0 software. Results show that using fluid viscous dampers to putting together effectively reduce the building responses by selecting optimum damping coefficient i.e. when the building is connected to the fluid viscous dampers (FVD) can control both displacements and accelerations of the building. Further damper at appropriate locations can significantly reduce the earthquake response.

Author(s):  
Timothy Graf ◽  
James O. Malley ◽  
Mark Sinclair ◽  
James Newell ◽  
Colin Blaney ◽  
...  

2021 ◽  
Vol 7 ◽  
Author(s):  
Michele Palermo ◽  
Vittoria Laghi ◽  
Giada Gasparini ◽  
Stefano Silvestri ◽  
Tomaso Trombetti

The paper investigates the dynamic behavior of structural systems obtained by connecting a moment-resisting frame structure with a vertical rigid truss pinned at the base, known in literature as “strongback,” and equipped with added fluid-viscous dampers. The strongback, designed in order to remain in the elastic field under strong seismic ground motion, acts as a mast by imposing to the structure a linear lateral deformed shape. By regularizing the lateral drift profile of the structure, the strongback limits undesired effects such as weak-storey mechanisms, damage concentration and residual drifts. In addition, when supplemental dampers are inserted in the structure, a considerable amount of energy can be dissipated, thus reducing the peak seismic response. The aim of the work is twofold: i) to provide analytical formulations for the preliminary design of added dampers based on the Generalized Single Degree Of Freedom (GSDOF) concept, and ii) to evaluate the increase in energy dissipation capabilities for selected dampers configurations thanks to the presence of the strongback. The formulas are developed for different configurations of added viscous dampers: dampers inserted within the frame between all or selected consecutive storeys (inter-storey placement) and dampers located at the base of the strongback to realize a rigid “dissipative tower.” The effectiveness of the dampers configurations is evaluated through dynamic time-history analyses.


Author(s):  
Ashutosh Shrivastava ◽  
Rajesh Chaturvedi

Nowadays, as in the urban areas the space available for the construction of buildings is limited. So in limited space we have to construct such type of buildings which can be used for multiple purposes such as lobbies, car parking etc. To fulfill this demand, high rise buildings is the only option available. The performance of a high rise building during strong earthquake motion depends on the distribution of stiffness, strength and mass along both the vertical and horizontal directions. If there is discontinuity in stiffness, strength and mass between adjoining storeys of a building then such a building is known as irregular building. The present study focuses on the seismic performance of regular and vertical irregular building with and without masonary infills. In the present study G+11 building is considered for the analysis with modelling and analysis done on ETABS software v17.0.1. The earthquake forces are calculated as per IS 1893 (part 1): 2016 for seismic zone III. The width of strut is calculated by using equivalent diagonal strut method. Total five models are considered for the analysis i.e. regular building with bare frame, regular building with masonary infill, soft storey building with open ground storey, mass irregular building with masonary infill and vertical geometric irregular building with masonary infill. The non-linear static analysis (pushover analysis) and linear dynamic analysis (response spectrum analysis) are performed for all the models and thereby compare their results. From analysis, the parameters like performance point, time period, maximum storey displacement, maximum storey drifts, storey shears and overturning moments are determined and also comparative study is done for all the models. From the comparison, it is observed that the vertical geometric irregular building shows better performance under seismic loading and bare frame building shows inferior performance. Moreover, the performance of masonary infilled frame building is f


2018 ◽  
Vol 763 ◽  
pp. 967-974 ◽  
Author(s):  
Bai Ping Dong ◽  
Richard Sause ◽  
James M. Ricles

Real-time hybrid earthquake simulations (RTHS) were performed on steel moment-resisting frame (MRF) structures with nonlinear viscous dampers. The test structures for the RTHS contain a moment-resisting frame (MRF), a frame with nonlinear viscous dampers (DBF), and a gravity load system with associated seismic mass and gravity loads. The MRFs have reduced beam section beam-to-column connections and are designed for 100%, 75%, and 60%, respectively, of the base shear strength required by ASCE 7-10. RTHS were performed to evaluate the seismic performance of these MRF structures. Two phases of RTHS were conducted: (Phase-1) the DBF is the experimental substructure in the laboratory; and (Phase-2) the DBF with the MRF is the experimental substructure. Results from the two phases of RTHS are evaluated. The evaluation shows that the RTHS provide a realistic and accurate simulation of the seismic response of the test structures. The evaluation also shows that steel MRF structures designed with reduced strength and with nonlinear viscous dampers can have excellent seismic performance.


Seismic analysis of structure is employed to make the structure enable to resist the seismic forces and perform against the factors causing the failure of the structure under dynamic excitation. Among various response factors, the base shear and time period of buildings are predominant factors used in the analysis and design of the structure. The prime objective of the paper is to present an analytical study on non-linear seismic analysis of moment resisting framed buildings (as per Indian code IS1893 – 2016) to evaluate the base shear of different configurations of buildings according to different mode combination methods. The obtained results have been presented the comparative analysis of different combination methods. The paper also presents the evaluated results in the form of the time period values of the different buildings depending upon variation in its configuration. As a result, the responses of multistoried moment-resisting framed buildings have been evaluated for various models of considered buildings based on different mode combination methods, and the results of obtained responses have been analyzed in a comparative manner to understand the behaviour of buildings under various methods and configuration conditions. The work presented in the paper can support to develop better understanding of structural response and efficient designing of structures.


Sign in / Sign up

Export Citation Format

Share Document