Journal of Civil Engineering and Environmental Technology Print ISSN: 2349-8404; Online ISSN: 2349-879X; Volume 2, Number 12; April-June, 2015 pp. 27-31 © Krishi Sanskriti Publications http://www.krishisanskriti.org/jceet.html Protection of the Buildings from the Earthquake Risk Using High Damping Rubber Bearing S.D. Gowardhan 1 and Manoj U. Deosarkar 2 1 Applied Mechanics Department Government College of Engineering, Amravati, Maharashtra 444604 2 Post-Graduate Student, Applied Mechanics Department Government College of Engineering, Amravati, Maharashtra 444604 E-mail: 1 dhepesharvari@gmail.com, 2 manojdeosarkar@gmail.com Abstract—In past few years, passive control mechanisms including base isolation systems are gaining large attention as mean to protect structures against seismic hazard. The effectiveness of an isolation system depends upon the dynamic characteristics of earthquake ground motion and the building superstructure. The base isolation system separates the structure from its foundation and primarily moves the natural frequency of the structure away from the dominant frequency range of the excitation via its low stiffness relative to that upper structure. In order to verify the effect of base isolation system, the structure is presented as symmetrical building in which the seismic responses of the 'fixed-base' and 'base-isolated' conditions have been compared using a well-known computer program SAP2000 version 14. The aim of this study is to reduce the base shear, story drifts and story acceleration due to earthquake ground excitation, applied to the superstructure of the building by installing base isolation devices at the foundation level and then to compare the different performances between the fixed base condition and base-isolated condition of symmetrical building. The high damping rubber isolation system has been used at the foundation level. Non linear time history analysis has been performed on El-Centro earthquake. Comparing the results of the base -isolated condition with those obtained from the fixed-base condition has shown that the base isolation system reduces the base shear force, story drifts and storey acceleration, also increasing the storey displacement and time period. Keywords: Earthquake, Base Isolation, Non Linear Time History Analysis, High Damping Rubber Bearing. 1. INTRODUCTION Earthquakes are one of nature’s greatest hazards; throughout historic time they have caused significant loss of life and severe damage to property, especially to man-made structures. On the other hand, earthquakes provide architects and engineers with a number of important design criteria foreign to the normal design process. From well established procedures reviewed by many researchers, seismic isolation may be used to provide an effective solution for a wide range of seismic design problems. The application of the base isolation techniques to protect structures against damage from earthquake attacks has been considered as one of the most effective approaches and has gained increasing acceptance during the last two decades. This is because base isolation limits the effects of the earthquake attack, a flexible base largely decoupling the structure from the ground motion, and the structural response accelerations are usually less than the ground acceleration [1]. Many comparative studies have revealed that the responses of the isolated structure are significantly smaller than the fixed base structure. Most of these studies compared the seismic demands (e.g. inter story drift, floor acceleration and base shear) for the two types of building structures, but only a limited number of studies investigated the responses of the isolated structure using high damping rubber bearing (HDRB) with detailed procedures of the design of HDRB. Nassani and Mustafa [1] presented as two different structures are (symmetrical and non-symmetrical school buildings) in which the seismic responses of the 'fixed-base' and 'base-isolated' conditions using SAP2000. Comparing the results of the base - isolated condition with those obtained from the fixed-base condition has shown that the base isolation system reduces the base shear force and story drifts, whilst also increasing the displacement. Akhare and Wankhade [2] studied to use of High density rubber bearing (HDRB) and friction pendulum system (FPS) as an isolation device and then to compare various parameters between fixed base condition and base isolated condition by using SAP2000v14 software. In this study the (G+12) storey hospital building is used as a test model. Nonlinear time history analysis is carried out for both fixed base and base isolated structure. The result obtained shows the reduction in base shear in both direction and increase in the displacement and time period for the base isolated structure. Gomase & Bakre [4] studied force deformation behaviour of an isolator is modeled as Bi-linear hysteretic behaviour which can be effectively used to model all isolation system in practice. Floor acceleration and inter- story drifts of the subject base isolated building are significantly reduced when compared to its fixed base counterpart. Tourunbalci & Ozpalanlar [3] presented energy approach to the earthquake resistant structure design. They studied the numerical example on six storey structure and