University of Qom Civil Infrastructure Researches 2783-140X 2 1 2016 08 22 Study of the modification factor of concrete bridges with Elastomeric Rubber Bearing (ERB) and Lead Rubber Bearing (LRB) Study of the modification factor of concrete bridges with Elastomeric Rubber Bearing (ERB) and Lead Rubber Bearing (LRB) 13 24 750 10.22091/cer.2015.750 FA Ehsan Dehghani Assistant Professor, Faculty of Engineering, University of Qom 0000-0002-7030-5948 Seyed Omid Mousavi MSc Student, Faculty of Engineering, University of Qom Journal Article 2016 03 12 By examining the results of the analysis of the modification factor of the bridge with LRB isolators for x and y, respectively 2.32 and 3.95 and modification factor of bridge isolators ERB to x and y, respectively 2.57 and 4.25 was calculated. So modification factor of the bridge with LRB isolators for x and y is less than ERB isolators that represents the LRB bearings will cause that substructure is less inside nonlinear phase. Also the modification factor is less than the factor of “Publication 463” –it is in the x and y respectively 3 and 5- that indicates isolators reduce the nonlinear behavior of structural parts and lower general modification factor of the structure. The modification factor of isolators of bridge is less than the amount listed in the code. Although there is no significant difference but it less of it can be a reason for further investigation and as well as selected and proposed new factors for bridge with isolators in the codes.<br /> In addition, the effect of reduction in the spans can be seen in two cases that there is no significant effect in various spans of bridge. By examining the results of the analysis of the modification factor of the bridge with LRB isolators for x and y, respectively 2.32 and 3.95 and modification factor of bridge isolators ERB to x and y, respectively 2.57 and 4.25 was calculated. So modification factor of the bridge with LRB isolators for x and y is less than ERB isolators that represents the LRB bearings will cause that substructure is less inside nonlinear phase. Also the modification factor is less than the factor of “Publication 463” –it is in the x and y respectively 3 and 5- that indicates isolators reduce the nonlinear behavior of structural parts and lower general modification factor of the structure. The modification factor of isolators of bridge is less than the amount listed in the code. Although there is no significant difference but it less of it can be a reason for further investigation and as well as selected and proposed new factors for bridge with isolators in the codes.<br /> In addition, the effect of reduction in the spans can be seen in two cases that there is no significant effect in various spans of bridge. https://cer.qom.ac.ir/article_750_a36bd2f5756c881dc06765c4ca6233d7.pdf