PERHITUNGAN ULANG PERENCANAAN STRUKTUR GEDUNG MENGACU KEPADA PERSYARATAN FEMA DAN ASCE/SEI 7-10
Andre Ricky, Ashar Saputra, S.T., M.T., Ph.D.,
2012 | Tesis | S2 Teknik SipilGempa merupakan satu fenomena alam yang sering terjadi di Indonesia. Gempa dapat menimbulkan getaran tanah yang berpengaruh terhadap struktur bangunan yang ada. Untuk itu, di dalam perencanaan struktur bangunan, setiap perencana harus mempertimbangkan keberadaan beban gempa tersebut. Penelitian ini menggunakan FEMA 450 dan ASCE 7-10 dalam mengevaluasi struktur bangunan terhadap gempa dengan studi kasus Gedung IGD, Gedung Klinik, dan Gedung Administrasi Rumah Sakit Akademik UGM. Penelitian dilakukan dengan metode numeris menggunakan perangkat lunak SAP2000 versi 11. Data yang diperlukan sebagai input perangkat lunak diperoleh dari as-built drawing RSA UGM dan laporan perhitungan struktur yang diperoleh dari PIU-UGM untuk memodelkan Gedung IGD, Gedung Klinik, dan Gedung Administrasi RSA UGM. Pemodelan gempa dilakukan dengan menggunakan response spectrum dari perangkat lunak yang memuat data gempa terbaru dengan nilai R=3,5 dan R=4. Pemodelan tersebut menghasilkan output yang digunakan sebagai data pembanding terhadap kriteria penerimaan keamanan bangunan, yaitu drift dan member forces. Namun, sebelum mengevaluasi member forces elemen struktur, ada atau tidaknya efek P-delta dan efek torsional irregularity perlu dievaluasi karena berpengaruh terhadap load combination yang digunakan untuk mengetahui member forces. Hasil perhitungan ulang menunjukkan bahwa pemodelan Gedung IGD, Gedung Klinik, dan Gedung Administrasi RSA UGM memenuhi persyaratan untuk batasan drift. Nilai q untuk ketiga gedung kurang dari batas sehingga efek P-delta dapat diabaikan. Analisis Efek torsional irregularity sudah disertakan dalam analisis. Dari hasil running perangkat lunak, member forces dari beberapa elemen pada ketiga gedung diperoleh dan beberapa elemen tidak mampu menahan beban geser dan terdapat capacity ratio yang melebihi batas untuk beberapa elemen berdasarkan kriteria penerimaan.
Earthquake is a natural phenomenon which was happening frequently in Indonesia. Earthquake can make ground motion which affect to the existing building structure. Therefore, in designing building structure, every designer must consider the existence of that earthquake. This research used FEMA 450 and ASCE 7-10 in evaluating building structure due to earthquake with case study IGD Building, Clinic Building, and Administration Building of Academic Hospital of UGM. This research was done by numerical method by using SAP2000 version 11 software. Data which was needed as input of software was got from as built drawing Academic Hospital UGM and Structure Calculation Report from PIU-UGM to model IGD Building, Clinic Building, and Administration Building of Academic Hospital of UGM. Earthquake modeling was done by using response spectrum from the software that contained the newest earthquake data with value of R is equal to 3.5 and 4. That modeling produced output which was used as comparing data to the building safety acceptance criterion, that were drift and member forces. But, before evaluating member forces of structure elements, the existence of P-delta and torsional irregularity effect had to be evaluated because it could affect to the load combination which was used to know the member forces. The result of recalculation showed that modeling of IGD Building, Clinic Building, and Administration Building of Academic Hospital of UGM fulfilled the requirements for drift limits. The value of q for those three buildings was less than the limit so the P-delta effect could be ignored. Torsional irregularity effect analysis was included in the analysis. From the running result of the software, member forces from some elements of those three buildings were found and some elements could not hold shear forces and there were capacity ratios which were bigger than the limit for some elements according to acceptance criteria.
Kata Kunci : RSA UGM, FEMA, gempa