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1. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 05 Issue: 03 | Mar-2018 www.irjet.net p-ISSN: 2395-0072
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Case study on Lead Rubber Isolation Bearing
Saurabh P. Kharat 1, Dinesh N. Biradar2, Ajay S. Sagekar3, Prathamesh V. Chavan4,
Prof. Reshma Shaikh5
1,2,3,4 Student, Department of Civil Engineering, DRIEMS College, MAHARASHTRA, INDIA
5Professor, Department of Civil Engineering, DRIEMS College, MAHARASHTRA, INDIA
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Abstract – Earthquake represent one among the best hazards of life and property on the planet. Because of
hurriedness of their prevalence, they're least understood and most fearful. The earthquake resistant construction is
taken into account to be vital to mitigate their effects. Earthquake resistant structures area unit structures designed
to resist earthquake. whereas no structure will be entirely proof against harm from earthquake, the goal of
earthquake resistance construction is to erect structures that fare higher throughout seismic activity than their
standard counterparts. For earthquake resistant structure the foremost effective material that we have a tendency to
area unit victimisation is lead rubber bearing. Seismic Base-isolation of building is associate degree innovative
technique employed in year for reducing seismic energy transmitted to assembling in extremely seismic prone space.
The essential principle behind the bottom isolation system is to introduce a versatile interface between the bottom of
a structure and therefore the foundation. Laminated Rubber Bearings area unit the foremost wide used technology in
seismic base isolation, owing to their technical and economic effectiveness and dependableness. Despite the fact that
base isolation technique is extensively used for over 8000 structures internationally, this technique is extremely
seldom employed in Republic of India in spite of the actual fact that India has such a lot of extremely seismically
active zones. excluding the trendy techniques that area unit well documented within the codes of apply, there area
unit another recent ancient earthquake resistant techniques that have evidenced to be effective for resisting
earthquake loading and are value effective with simple constructability. This paper presents the transient necessities
of earthquake resistant construction and a way to enhance the resistance of building and building materials to
earthquake forces, economically.
Keywords- Base isolation; Earthquake; Near-fault motion; Lead–rubber bearings; Bearing yield strength;
Superstructure flexibility.
1. INTRODUCTION
The earthquake is a disruptive disturbance that cause shaking of surface of the earth due to undergoes moment
along a fault plane or from volcanic activity is called Earthquake. Earthquake resistant structure is structure
designed to withstand earthquakes. While no structure can be entirely immune to damage from earthquakes. Base
isolation is a most effective method for earthquake resisting structure.
“Earthquake doesn’t kill folks, folded building do”. The Indian landmass contains a history of devastating earth
quakes. The most recent version of unstable seismic zoning map of India given within the earthquake resistant
design code of India [IS 1893 (Part 1) two002] divides India into four unstable zones (Zone 2, 3, 4 and 5), with
Zone five expects the best level of seismicity whereas Zone two is related to very cheap level. every zone
indicates the results of Associate in Nursing earthquake at a selected place supported the observations of the
affected areas and may even be delineated employing a descriptive scale like changed Mercalli intensity scale or
the Medvedev-Sponheuer-Karnik (MSK) scale. The MSK intensity generally related to the varied unstable zones is
VI (or less), VII, VIII and IX (and above) for Zones two, 3, 4 and 5, severally, like most thought-about Earthquake
(MCE). Zone 5, that is mentioned because the terribly High injury Risk Zone within the IS code, assigns zone
issue of zero.36 to it, that is indicative of effective (zero period) peak horizontal ground accelerations of zero.36 g
(36% of gravity) which will be generated throughout MCE level earthquake during this zone. The state of
Kashmir, the western and central Himalayas, the North-East Indian region and also the Ran of tannic acid fall
during this zone.
A variety of isolation devices as well as elastomeric bearings (with and while not lead core), frictional/sliding
bearings and roller bearings are developed and used much for a seismic style of buildings throughout the last
twenty years [1,2]. Among the varied base isolation systems, the lead–rubber bearings (LRB) had been used
extensively in New Zealand, Japan and u. s. The LRB consists of alternate layers of rubber and steel plates with
one or additional lead plugs that area unit inserted into the holes. The lead core deforms in shear providing the
linear response (i.e. adds hysteretic damping within the isolated structure) and conjointly provides the initial

2. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 05 Issue: 03 | Mar-2018 www.irjet.net p-ISSN: 2395-0072
© 2018, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 3252
rigidity against minor earthquakes and robust winds [3]. The primary building isolated by the LRB was the
William Clayton building in Wellington, New Zealand completed in 1981 and followed by alternative buildings in
many countries. The buildings isolated with LRB performed fine throughout the 1994 Northridge and 1995 Kobe
earthquakes confirming the suitableness of LRB as a base isolator. The performance of the LRB system with
designated property was conjointly not rumored to be terribly satisfactory below near-fault motions within the on
top of studies. Since the LRB system could be a quite common isolation system equipped with all fascinating
options for base isolation, it's necessary to check the dynamic behavior of the LRB system and its optimum
parameters below the near-fault motions. Here, the response of multi-storey buildings and bridges isolated by the
LRB is investigated below near-fault motions. the particular objectives of the study area unit (i) to check the
performance of structures isolated by LRB below near-fault motions, (ii) to research the optimum parameters of
the LRB for minimum earthquake response of the isolated system below near-fault motions, (iii) to check the
variation of optimum parameters of the LRB below totally different system parameters of construction and
isolation systems, and (iv) to research the unstable response of bridge with LRB below near-fault motions.
2. MEHODOLOGY
The methodology utilized during this study was to watch and monitor this sort of elastomeric bearings comprises
skinny layers of low damping natural rubber and steel plates in-built alternate layers and a lead cylinder plug
firmly fitted in an exceedingly hole at its centre to deform in pure shear. The steel plates within the bearing force
the lead plug to deform in shear. This bearing provides associate degree elastic restoring force and additionally,
selectively of acceptable size of lead plug, produces needed quantity of damping. The force deformation behaviour
of the bearing. Performance of LRB is maintained throughout continual robust earthquakes, with correct sturdiness
and liableness.

3. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 05 Issue: 03 | Mar-2018 www.irjet.net p-ISSN: 2395-0072
© 2018, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 3253
2.1 SCHEMATIC DIAGRAM
2.2 CASE STUDY
To study the impact of victimization Lead rubber referring to the buildings to hold the seismic forces in
extremely seismic prone areas, in Indian conditions with totally different soil creation strata, Lead Rubber
Bearings area unit designed for a planned medium height information center building close to Delhi region of
Republic of India. Information center could be a heavily loaded building, that is handling terribly sensitive
electronic info of assorted company teams. The information keep got to be protected and also the performance of
information center got to proceed uninterrupted, throughout and when the prevalence of an important earthquake.
Even if the building is found in zone IV, as per client’s request, it's designed for one zone higher i.e. zone V. The
structure is analyzed with Soil Structure Interaction, for varied creation Strata of Hard, Medium and Soft Soils for
parametric comparison.
The structure is to be analyzed for all loads with and without LRBs fitted to all columns and shear walls as per
codal requirements. Parametric comparison is to be done for all seismic parameters for the building analyzed with
and without base-isolators.

4. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 05 Issue: 03 | Mar-2018 www.irjet.net p-ISSN: 2395-0072
© 2018, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 3254
3. CONCLUSION
Base lateral displacements and toe storey displacement were also found to be within reasonable limits. The study
shows the effectiveness of the LRB base isolation system in terms of reduced structural responses under seismic
loading. As the base isolators are extensively used worldwide in high seismic areas in near future we will except
the same in India also. At least in seismic zone 4 and 5 the use of base isolators has to be encouraged as they
are technically very effective and economically feasible.
The use of base isolators reduces inter-story drift and structural damages during earthquake. The building will be
ready to occupy with minor repair. The results of this work demonstrated that base isolators are excellent seismic
control devices for high raise symmetric buildings. Base isolation method has proved to be a reliable method of
earthquake resistant design. Therefore it is concluded that building with base isolation remains strong enough
during an earthquake as compared to fixed base building.
REFERENCES
(1) R.S. Jangid ‘’Stochastic response of building with Lead rubber bearings.
(2) Effectiveness of Lead Rubber Base Isolators for seismic resistance of Buildings supported on different soil
strata’s
(3) Skinner RI, Beckand JI, Bycroft GN. A practical system for isolating structures from earthquake attack
Earthquake engineering and Structural Dynamics ;3:297-309(1975)
(4) R .S Jangid “Optimum lead–rubber isolation bearings for near-fault motions”