Di Malaysia, hampir semua bangunan telah direka tanpa menggabungkan daya gempa bumi, walaupun baru-baru ini (kawasan Ranau) Sabah telah dilanda gempa bumi dengan magnitud 6.0. Gempa bumi tidak boleh dielakkan tetapi kesannya boleh dikurangkan dengan meningkatkan kestabilan struktur. Kajian ini memberi tumpuan kepada penilaian seismik terhadap bangunan konkrit bertetulang berbentuk T- (pelan ketaksekataan). Dua belas model yang mempunyai lokasi teras lif dan ketinggian bangunan yang berbeza telah dihasilkan. Analisis berangka dilakukan dengan bantuan pakej perisian SAP2000. Keputusan yang berkaitan dengan pesongan bangunan, maksimum kilasan tiang, kewujudan-bersama ricih, kewujudan-bersama momen dan momen sambungan pada rasuk ke tiang direkodkan dan dibincangkan dengan sewajarnya.
Model tingkat 6 menunjukkan prestasi seismik yang lemah apabila teras lif itu terletak di tengah-tengah sayap di atas model bentuk T. Ini adalah benar bagi kebanyakan keputusan kecuali kilasan. Magnitud kilasan adalah sensitif kepada lokasi teras lif. Walau bagaimanapun, kewujudan-bersama ricih dan momen didapati tidak menjadi nilai maksimum berkaitan dengan kilasan maksimum. Tiada trend yang jelas diperhatikan untuk mengaitkan tindak balas seismik dengan lokasi teras lif apabila ketinggian bangunan telah meningkat. Dalam erti kata lain, lokasi lif teras dikawal oleh jenis kegagalan yang berbeza dan benar, terutamanya apabila bangunan bentuk-T menjadi langsing. Momen kilasan mengekalkan perbezaan peratusan yang tinggi untuk lokasi lif teras yang berbeza dengan ketinggian bangunan. Oleh itu, dalam kerja reka bentuk sebenar, lokasi teras lif perlu dikaji dengan teliti untuk mengurangkan kegagalan yang dikaitkan dengan momen kilasan.
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In Malaysia, almost all buildings were designed without incorporating earthquake force, although recently Sabah (Ranau area) was struck by a 6.0 magnitude earthquake. Earthquakes cannot be prevented but the impact can be minimised by enhancing the stability of the structures. This study focused on the seismic assessment of reinforced concrete T-shape building (plan irregularity).Twelve models, each having different lift core location and building heights were generated. The numerical analysis was performed with the aid of SAP2000 software package. Results pertaining to the building displacement, maximum column torsion, co-existence shear, co-existence moment and moment at the beam to column connection were recorded and discussed accordingly.
The 6-storey model showed poor seismic performance when the lift core was located at the centre of the top wing of the T-shape model. This is particularly true for most of the results except for torsion. The magnitude of torsion was sensitive to the location of the lift core. However, he co-existence shear and moment were found not be the maximum value with respect to the maximum torsion. No obvious trend was observed to relate the seismic response with the location of the lift core as the building heights were increased. In other words, different lift core locations governed different types of failure and particularly true when as the T-shape building became slender. Torsional moment maintained high percentage difference for different lift core position and building height. As such, in real design work, the location of the lift core must be studied carefully in order to significantly reduce the failure associated to torsional moment.
Analysis of reinforced concrete buildings with plan irregularity subjected to seismic load / Junaidah Abdullah