Menara penghantaran terdiri daripada keratan sesiku yang dihubungkan secara eksentrik di satu bahagian kaki. Secara umumnya, perisian komersial menghasilkan secara automatik sambungan anggota sebagai sepusat. Pemodelan jenis ini mengabaikan orientasi sebenar anggota menara. Sambungan eksentrik boleh meningkatkan daya dalaman dan perlu disiasat. Di dalam kajian ini, menara transmisi 132 kV telah dihasilkan dan dianalisis dengan menggunakan perisian komersil STAAD Pro. V8i. Sasaran kajian ini adalah untuk menyiasat perubahan daya dalaman dan keupayaan terguna terhadap anggota utama menara penghantaran tersebut. Terdapat dua jenis model telah dibangunkan untuk membezakan sambungan anggota sepusat dan eksentrik. Di samping itu, beban normal dan tiga set keadaan kepecahan wayar telah digunakan untuk semua model. Perbezaan di dalam daya paksi anggota telah dikira dan dibincangkan dengan sewajarnya. Keputusan menunjukkan daya paksi dalam anggota utama meningkat disebabkan keadaan beban biasa apabila arah angin dikenakan pada paksi-x. Berbanding dengan keadaan beban biasa, model yang keadaan kepecahan wayar menunjukkan peningkatan yang lebih tinggi didalam daya paksi yang disebabkan oleh sambungan eksentrik. Di samping itu, dari aspek kekuatan mampatan maksimum, perbezaan peratusan tertinggi antara sambungan sepusat dan eksentrik berlaku didalam keadaan (G.W) dawai pecah apabila angin yang dikenakan pada paksi-x. Tambahan pula, salah satu dari anggota yangh terletak pada sangkar menara telah mengalami kegagalan apabila dikenakan keadaan (T.C + M.C) keadaan wayar pecah. Di dalam kes ini, keupayaan terguna telah melebihi 6.82%. Peningkatan yang ketara didalam daya dalaman anggota dan kemungkinan kegagalan menara penghantaran disebabkan oleh sambungan anggota secara eksentrik mencadangkan agar orientasi sebenar anggota menara mesti diambil kira di dalam reka bentuk menara penghantaran.
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Transmission tower is made up of angle sections that are connected eccentrically by one leg of the section. Generally, commercial software automatically generates the connection of the member as concentric. This type of modelling ignores the actual orientation of the tower members. The eccentric connection may increase the internal forces and need to be investigated. In this study, numerical model of 132 kV transmission tower was generated and analysed with the aid of STAAD Pro. V8i commercial software. The aim is to investigate the change in the member forces and used capacity of main tower members due to eccentric connection. Two types of models were developed to differentiate the members with concentric and eccentric connection. In addition, normal loading condition and another three sets of broken wire conditions were applied to all models. The differences in the member axial forces were calculated and discussed accordingly. The results showed that the axial force in the main members increased under normal loading condition when the wind direction was applied in x-axis. Compared to normal loading condition, models with broken wire condition showed higher increase in the axial forces due to eccentric connection. In addition, the highest percentage differences in terms of maximum compressive force between concentric and eccentric connection was developed in (G.W) broken wire condition subjected to wind in x-axis. Moreover, one of the members located on the tower cage failed when subjected to (T.C + M.C) broken wire condition. In this case, the used capacity was exceeded by 6.82%. The significant increase in the internal member forces and possible failure of tower member due to eccentric member connection suggests that the actual orientation of the tower members must be considered in the design of transmission towers.
Numerical investigation on the effect of member orientation to the strength of transmission tower / Karen Yong Bee En