PARAMETRIC STUDY ON CURVED BRIDGES SUBJECTED TO SEISMIC LOADING

Shashi Kumar N S , Ashwini B T , Dr. B.M Gangagadharappa

Box girder Bridge, I girder Bridge, Radius of Curvature, Column Skewness

As India is developing, the infrastructure is gaining a lot of importance. This project aims at infrastructure development such as bridges. The curvature in the bridges is usually introduced to eliminate the support irregularities or presence of important structures which cannot be demolished. Due to the curvature in the bridge there will be large centrifugal reactions on the vehicles. Apart from the reaction a large torsional moment will be induced on the supporting girders. The column’s location and orientation is also a major design criteria in bridges. When the columns are tilted from the normal angle the column is said to be skewed. Skewed column decreases the stability of structures as seen in the previous literatures. Skewed columns along with some degree of horizontal curvature to the bridges create a lot of instability. In this project bridges subjected to seismic loads and its behavior when the bridge is curved horizontally at deck section and skewed at column or pier section is dealt. The bridge model considered for the project consisted of 2 spans each of 50m, with abutments at both ends and piers at mid-section. 2 columns of 1.5m diameter were considered at mid-section. In this project Box girder bridge and I girder bridge are compared with horizontal curvature being (R= inf, 150m, 250m) and column skewness with (0, 15, 30 degrees) variation. The software used for the study is CSI Bridge 2016 v18 subjected to seismic load subjected to code of 1893 2002 and IRC 6 for vehicle loading. The pushover results showed that combined effect of both radius of curvature and skewness of column greatly reduces the base shear reaction ie for Box girder section the base reaction reduced to 1600 for 30 degree skew and 150m radius of curvature.

Volume 3 Issue 6, June-2018

Pages : 253 - 266