ANALYTICAL STUDY THE EFFECTS OF VARIOUS OF SEISMIC ISOLATION SYSTEMS ON A STEEL ARCH BRIDGE

• Main Author: Bachtiar, Yusuf
• Format: Theses
• Language: Indonesia
• Subjects: Teknik sipil
• Online Access: https://digilib.itb.ac.id/gdl/view/77323
• Institution: Institut Teknologi Bandung

This study focuses on the seismic response analysis of the Youtefa Bridge, employing a Friction Pendulum System (FPS) of the Sliding Isolation Pendulum (SIP) type as a bridge bearing due to its worldwide recognition as a Seismic Isolation system (SIS). This decision is driven by the seismic vulnerability of the 400-meter long steel arch bridge located in Jayapura, which experiences significant earthquake loads, with an estimated Peak Ground Acceleration (PGA) in of 0.7-0.8 g. The implementation of FPS is expected to significantly alter the bridge's seismic behavior compared to situations without seismic Isolation or with other isolator devices. The study examines three widely adopted Seismic Isolation Systems: Friction Pendulum System (FPS), High-Damping Rubber Bearings (HDRB), and Lead Rubber Bearings (LRB). The primary objective is to contrast the structural responses of various models, including FPS, HDRB, and LRB, under both design displacement and historical earthquake loading conditions. The investigation employs four models simulating the Youtefa Bridge, utilizing Nonlinear Time History Analysis (NLTHA) with earthquake histories tailored to match spectral response targets. The analysis encompasses crucial parameters such as critical element identification, mass participation, natural period determination, composite response spectrum evaluation, base shear assessment, superstructure deformation and displacement analysis, and hysteresis curve examination across the three Isolation devices. The results indicate the superior performance of the FPS device in mitigating the effects of seismic forces when compared to HDRB and LRB devices. This superiority is manifested through its remarkable reduction in base shear, relatively minor superstructure displacement, and sustained hysteresis curve behavior within the cross-sectional capacity limits.