Kajian Pengaruh Panjang ‘Back Span’ pada Jembatan Busur Tiga Bentang

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ABSTRAK

Penelitian ini melakukan kajian pengaruh variasi bentang ‘back span’ pada jembatan. Jembatan yang dikaji adalah jembatan baja profil persegi tubular dengan bentang utama 150 meter dan ‘back span’ 51,2 meter. Ada 6 variasi penambahan dan pengurangan terhadap bentang ‘back span’ jembatan acuan awal yaitu : Model 1 berupa penambahan 10 meter, Model 2 berupa penambahan 5 meter, Model 3 berupa penambahan 0 meter, Model 4 berupa pengurangan 5 meter, Model 5 berupa pengurangan 10 meter, dan Model 6 berupa pengurangan 25 meter. Hasil analisis nilai terbesar menunjukan Model 1 sebesar 78.693,89 kN untuk reaksi perletakan rol, Model 1 sebesar 305,8 mm di girder jembatan untuk lendutan, Model 1 sebesar 21.611,454 kN di girder untuk aksial, Model 1 sebesar 36.775,691 kN di girder untuk momen lentur, dan model 1 sebesar 5.020,33 kN di girder untuk geser. Hal ini menunjukkan beban dari lengkung dan main span jembatan disalurkan menuju ‘back span’ seiring bertambahnya bentang.

Kata kunci: jembatan lengkung baja, ‘back span’

 

ABSTRACT

This research investigate the effect of variant ‘back span’ length in a bridge. The type of the studied bridge is a hollow tube steel bridge with 150 meter of main span and 51,2 meter of back span. There are 6 variations of the addition and subtraction of the bridge 'back span'  length, that is: Model 1 with 10 meters addition, Model 2 with 5 meters addition, Model 3 with 0 meters addition, Model 4 with 5 meters reduction, Model 5 with 10 meters reduction, and Model 6 with 25 meters reduction. Results of the analysis showed that Model 1 have the greatest value of 78693.89 kN for the for roll joint reaction, 1Model amounted to 305.8 mm in girder bridge for deflection, Model 1 amounted to 21.611,454 kN in girder for axial, Model 1 amounted to 36.775,691 kN in girder for momen, and 1 Model amounted to 5.020,33 kN in girder for shear. This show that with increasing of the length, loads from arch and main span are distributed towards ‘back span’

Keywords: steel arch bridge, ‘back span’