Evaluasi Kinerja Seismik Struktur Rangka Beton Pemikul Momen dengan Pengaruh Dinding Pengisi Menggunakan SNI 9273:2025 (Studi Kasus: Wilayah Gempa Kota Palu)

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ABSTRAK

bertulang sering kali menghasilkan prediksi perilaku seismik yang tidak akurat, khususnya di wilayah dengan intensitas gempa tinggi seperti Kota Palu. Penelitian ini bertujuan untuk mengevaluasi pengaruh interaksi dinding-rangka terhadap kinerja seismik gedung perkantoran 5 lantai pada kondisi tanah sedang (SD) menggunakan standar evaluasi terbaru SNI 9273:2025. Analisis dilakukan secara komparatif menggunakan Prosedur Dinamik Linear (Respons Spektrum) terhadap dua model struktur: Model A (Bare Frame) dan Model B (Infilled Frame) yang dimodelkan dengan metode makro Equivalent Diagonal Strut (Mainstone). Hasil simulasi menunjukkan bahwa pemodelan dinding pengisi meningkatkan kekakuan global secara signifikan, yang mereduksi periode getar fundamental sebesar 71%. Peningkatan kekakuan ini berimplikasi pada lonjakan Gaya Geser Dasar (Base Shear) sebesar 162% akibat pergeseran respons spektral ke area percepatan tinggi, namun secara efektif mereduksi simpangan antarlantai (drift) hingga 69%. Evaluasi kapasitas berdasarkan kriteria Force-Controlled menunjukkan bahwa dinding pada lantai 1-4 mengalami kegagalan geser dengan rasio DCR > 1,0. Kesimpulan studi ini menegaskan bahwa asumsi bare frame cenderung memberikan estimasi gaya geser dasar yang terlalu rendah (underestimate).

Kata kunci: dinding pengisi, Equivalent Diagonal Strut, Kota Palu, respon spektrum, SNI 9273:2025

ABSTRACT

Omitting the contribution of infill wall stiffness in the structural analysis of reinforced concrete buildings often leads to inaccurate predictions of seismic behavior, especially in areas with high earthquake intensity, such as Palu City. This study aims to evaluate the effect of wall-frame interaction on the seismic performance of a 5-story office building on moderate soil conditions (SD) using the latest evaluation standard SNI 9273:2025. The analysis was conducted comparatively using the Linear Dynamic Procedure (Spectrum Response) on two structural models: Model A (Bare Frame) and Model B (Infilled Frame), modeled with the Equivalent Diagonal Strut (Mainstone) macro method. The simulation results show that infill wall modeling significantly increases global stiffness, thereby reducing the fundamental vibration period by 71%. This increase in stiffness implies a 162% increase in Base Shear Force due to the shift in the spectral response toward the high-acceleration area, but effectively reduces the drift between floors (Drift) by 69%. Capacity evaluation based on Force-Controlled criteria indicates that walls on floors 1-4 experienced shear failure with a DCR ratio > 1.0. The conclusion of this study confirms that the bare frame assumption tends to provide an underestimate of the base shear force.

Keywords: infill wall, Equivalent Diagonal Strut, Palu city, spectrum response, SNI 9273:2025