Studi Pengaruh Infill Wall Terhadap Respons Seismik Struktur Open Frame dan Infilled Frame Berbasis Nonlinear Time History Analysis

Infill wall merupakan komponen yang hampir selalu digunakan pada struktur gedung. Namun, dalam proses analisis dan perencanaan, kontribusinya terhadap kekakuan dan perilaku struktur sering diabaikan. Padahal, pada kondisi gempa, keberadaan infill wall terbukti memberikan pengaruh signifikan terhadap respons dan kinerja struktur bangunan. Penelitian ini dilakukan dengan memodelkan infill wall sebagai equivalent diagonal strut pada sistem rangka beton bertulang. Analisis dilakukan dengan membandingkan respons struktur antara model open frame (tanpa infill wall) dan infilled frame (dengan infill wall). Evaluasi kinerja struktur dilakukan menggunakan analisis Nonlinear Time History Analysis (NLTHA). Sebanyak 11 ground motions untuk mengevaluasi dan memahami perilaku nonlinear struktur terhadap pembebanan seismik. Hasil penelitian menunjukkan bahwa penambahan infill wall pada gedung penelitian mampu menurunkan maximum displacement sebesar 27,47% serta meningkatkan nilai base shear struktur sebesar 30,70%. Namun penurunan displacement dan peningkatan base shear tidak berlaku untuk gedung secara umum yang mengindikasikan adanya peningkatan kekakuan dan kapasitas lateral struktur. Selain itu, keberadaan infill wall juga mereduksi tingkat kerusakan struktur dari level collapse prevention (CP) menjadi life safety (LS). Penambahan infill wall menyebabkan kapasitas daktilitas sistem pada model gedung penelitian ini cenderung menurun sebesar 17,05% dibandingkan struktur tanpa infill wall. Secara keseluruhan, hasil analisis menunjukkan bahwa keberadaan infill wall dalam pemodelan struktur secara signifikan mengubah mekanisme struktur dalam merespons deformasi lateral akibat beban gempa.

=================================================================================

Infill walls are components that are almost always used in building structures. However, in the analysis and planning process, their contribution to structural stiffness and behavior is often overlooked. However, under seismic conditions, the presence of infill walls has been shown to significantly influence the response and performance of building structures. This study was conducted by modeling the infill wall as an equivalent diagonal strut in a reinforced concrete frame system. The analysis was conducted by comparing the structural response between the open frame model (without infill wall) and the infilled frame model (with infill wall). The structural performance evaluation was conducted using Nonlinear Time History Analysis (NLTHA). A total of 11 ground motions were used to evaluate and understand the nonlinear behavior of the structure under seismic loading. The results showed that the addition of an infill wall to the research building reduced the maximum displacement by 27.47% and increased the structure’s base shear by 30.70%. However, this reduction in displacement and increase in base shear did not apply to buildings in general, indicating an increase in the structure’s stiffness and lateral capacity. Furthermore, the presence of infill wall also reduced the level of structural damage from the collapse prevention (CP) level to life safety (LS) level. The addition of an infill wall caused the system’s ductility capacity in this research building model to decrease by 17.05% compared to the structure without the infill wall. Overall, the analysis results indicate that the presence of infill wall in the structural model significantly alters the structure’s response to lateral deformation due to earthquake loads.