Performance Of Skew Integral Bridge Under Dynamic Loading
In this study, the integral and simply supported bridge with total length of 200 m non-skew and skews were designed, and modeled in SAP2000 software and analyzed the results in terms of moments, shears and stresses under static and dynamic loading were considered and checked with allowable stress method. Extreme stresses that exceed allowable limit in the superstructure and substructure of integral bridges were reduced by using six different stress reduction methods. The integral bridge analysis results were compared with that of simply support bridge result to analyze skew effect and integral effect. The propose of this study was to analyze behaviour of integral, skew angle, and to reduce extreme stress of integral bridge under dynamic loading. The parameters investigated in this analytical study were bridge support type, skew angle and stress reduction methods. The geometric dimensions of the Integral Bridge and the loading used were in compliance with AASHTO standard specifications. Static analysis and dynamic analysis of moving load analysis and nonlinear time history analysis were performed to assess the seismic performance of integral bridge. The FEA results indicate that under static live load, integral bridge girder shear force was minimum in skew 60, but maximum moment that was opposite to simply supported bridge girder. Under dynamic moving load analysis, integral abutment bored pile moment and shear force were maximum in skew 60, but maximum in skew 15 for integral pier bored pile. Under dynamic seismic time history analysis, maximum bending and shear stress occurred at integral abutment foundation and integral pier foundation in non-skew (0) and minimum skew angle 15 bridge, Among six stress reduction method, MSE wall and HLAC method can reduce stress within allowable limit for non-skew and skewed bridge over 90% and 23% respectively. According to analysis result, MSE wall is the best stress reduction method in skew and non-skew integral bridge.
Keywordsó Integral, bridge, skew, stress, static, dynamic, moving load, reduction, steel plate girders, integral abutment, and integral pier