PERBANDINGAN ANTARA DISAIN ELASTIS DAN DISAIN PLASTIS DALAM PERENCANAAN GELAGAR INDUK JEMBATAN KOMPOSIT

This research is aimed to investigate the comparison between elastic design and plastic design in designing main girder composite bridge. The result of the design shows us that main girder composite bridge which is designed by using plastic design is more economical compared to elastic design. We can see the comparison from the calculation that the stress of the upper main girder'sflanges aa=1,515.50 kglcm1 < aa=1,600 kglcm1 and the stress ofthe lower main girder's flanges aa=1,495.78 kg/cm 1 < ar:z=1,600 kglcm1 And the main girder composite bridge designed by plastic design is still stronger. We can see it from the safety factor n=2.249 > n=2.0. It means that the area of main girder composite bridge designed by using plastic design can be reduced. The length of the reinforce plate of the lower main girder's flanges designed by elastic design is 18.18 m ,and that designed by plastic design is only 4.28 m .We need 180 shear connectors for elastic design ,but we need only 168 shear connectors for plastic design.Hopefully this research can be used by the students in Technical Faculty in order to increase the quality of the students in Steel Construction Subject.Besides,this research is also can be used by the designers of the composite bridge to design stronger,more economical bridge.