ICSRR – E085 OPTIMIZED DESIGN OF LPB ISOLATORS FOR A SCHOOL BUILDING USING PERFORMANCE TARGETS Aishwarya Ra, Shrivarshini Ea, Abinaya Ishwarya G Kb*

Earthquakes pose significant risks to educational buildings, especially in seismic
regions where ground shaking can cause severe structural and non‑structural
damage. School buildings must maintain a higher level of safety because they
accommodate a large number of students and staff during working hours.
Traditional seismic design methods focus on increasing the strength and stiffness
of the structural system to resist earthquake forces. However, this approach often
results in large structural forces, potential damage to structural members, and
failure of non‑structural components such as ceilings, partitions, and laboratory
equipment. Base isolation has emerged as an effective seismic protection strategy
for reducing the forces transmitted from the ground to the structure. Lead Plug
Bearings (LPB) are widely used base isolation devices that provide flexibility
through rubber layers and energy dissipation through a central lead core. When
an earthquake occurs, LPB isolators allow controlled movement at the base of the
structure, thereby reducing the acceleration and deformation demands on the
superstructure. This project investigates the optimized design of LPB isolators for
a reinforced concrete school building using performance‑based targets. The study
defines structural performance objectives such as limiting inter‑storey drift,
reducing floor accelerations to ensure student safety, and minimizing base shear.
A parametric study is conducted by varying isolator stiffness, yield strength, and
damping characteristics to identify the most effective configuration. Structural
analysis results demonstrate that optimized LPB isolators significantly improve
seismic performance while maintaining constructability and cost efficiency.
Keywords: LPB isolators, earthquake, Lead Plug Bearings, isolator stiffness, yield
strength.