Kajian ini mengkaji kecekapan struktur keratan rasuk- I keluli berprofil web segi tiga
(TriWP) berlubang. Dua peringkat analisis telah dibuat dengan menganalisis 359
model. Di Peringkat 1, kecekapan struktur rasuk TriWP dengan bukaan yang
berdimensi 200 mm × 100 mm × 6 mm × 4 mm dan panjang rentang kira-kira 900 mm
ditentukan berdasarkan nisbah kapasiti beban kepada berat sendiri. Ia dikira di bawah
keadaan saiz lubang yang berbeza iaitu 0.4D, 0.5D dan 0.6D; lima bentuk bukaan yang
berbeza iaitu bulat, segiempat sama, heksagon, oktagon dan berlian dan susun atur
bukaan yang berbeza (Susun atur 1, Susun atur 2 dan Susun atur 3). Dengan
menggunakan kombinasi ini, analisis model dilaksanakan untuk keadaan lenturan,
lengkokan kilasan sisi, kilasan dan ricih pada peringkat kedua kajian. Pada peringkat
ini, bentuk, saiz dan susun atur bukaan yang paling cekap dipilih berdasarkan kepada
nilai kecekapan struktur tertinggi. TriWP dengan bukaan bersaiz 0.4D, bukaan
berbentuk berlian dan susun atur bukaan pada Susun atur 3 menunjukkan kecekapan
struktur yang tertinggi berbanding model-model lain. Nilai-nilai tersebut masingmasing
ialah 158.63, 799.0, 132.17 dan 204.75 dibawah keadaan beban seperti kelakuan lentur, lengkokan kilasan sisi, kilasan dan ricih. Di Peringkat 2, ketebalan web yang berbeza, ketebalan bebibir dan panjang rentang yang digunakan pada model yang dipilih dalam Peringkat 1 untuk memerhati prestasi dan tingkah laku di bawah empat keadaan beban iaitu lenturan, lengkokan kilasan sisi, kilasan dan ricih. Didapati bahawa apabila web dan ketebalan bebibir meningkat di bawah panjang rentang yang sama dengan lebar bebibir dan kedalaman web yang sama, nilai pesongan dan putaran
kilasan model masing-masing menurun di bawah keadaan beban lenturan dan kilasan.
Walau bagaimanapun, nilai-nilai (pesongan dan putaran kilasan) didapati meningkat
apabila panjang rentang yang meningkat. Selain itu, nilai kapasiti lengkokan ricih meningkat di bawah keadaan beban ricih dan nilai momen rintangan lengkokan juga didapati meningkat di bawah keadaan beban lengkokan sisi kilasan. Walau bagaimanapun, nilai keupayaan lengkokan ricih dan rintangan lengkokan didapati berkurangan apabila panjang rentang meningkat.
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This study investigates the structural efficiency of the triangular web profile (TriWP)
steel section with perforation. Two stages were included which comprised of 359
models that were analysed. In Stage 1, the structural efficiency of the TriWP with
perforation with the dimension of 200 mm × 100 mm × 6 mm × 4 mm and span length
of 900 mm is determined from the ratio of load carrying capacity to selfweight. It is
calculated under the condition of different perforation sizes i.e. 0.4D, 0.5D and 0.6D;
five different perforation shapes which are circular, square, hexagonal, diamond and
octagonal and three different layouts of perforations (Layout 1, Layout 2 and Layout
3). By using these combinations, the analysis of the model subjected to loading causing
bending, lateral torsional buckling, torsion and shear are analysed. In this stage, the
most efficient perforation shape, size and layout is selected based on the highest value
of structural efficiency. TriWP with the perforation size of 0.4D, diamond perforation
shape arranged in Layout 3 is found to shows the highest structural efficiency value
compared to other models. The values are 158.63, 799.0, 132.17 and 204.75 for
bending, lateral torsional buckling, torsion and shear loading conditions, respectively.
In Stage 2, different web thickness, flange thickness and span length are used on the
selected model in Stage 1 to observe the performance and its behaviour under four
loading condition i.e. bending, lateral torsional buckling, torsion and shear. It is found
that when the web and flange thickness are increased under the same span length with
constant flange width and web depth, the value of deflection and torsional rotation of
model decreased under bending and torsional loading conditions, respectively.
Nevertheless, these values (deflection and torsional rotation) are found to increase
when the span length increased. Moreover, the value of shear buckling capacity of
model is increased under shear loading condition and the value of moment buckling
resistance is also found to increase under loading causing lateral torsional buckling.
Nevertheless, the value of shear buckling capacity and moment buckling resistance are
found to decrease when the span length increased.