A Numeral Research on Effect of Vertical Component of Near Field Earthquakes on Long Span Bridges Built on Different Soil Conditions

In this study we tried to consider effect of vertical component of  near zone earthquake (10 to 15 km far from fault) such as Kobe 1995, Northridge 1994, Loma prieta 1989 and Chichi 1999 on a concrete cable bridge by a 320m span in the middle which was built on different type of soils. The SAP software (version14) was selected because I should have done linear and non-linear time history analysis by defining plastic hinges. Also we achieved to some results depended on types of soils and finally we extracted some factors for dead load to consider effect of vertical component of earthquakes on axial force, shear force and bending moment of different parts of the structure, also we gathered some results about horizontal and vertical displacement of span in the middle.