Please use this identifier to cite or link to this item:
https://ptsldigital.ukm.my/jspui/handle/123456789/486836| Title: | Development of live load distribution and dynamic impact factors of skewed multicell box-girder bridges subjected to moving vehicle loads |
| Authors: | Iman Mohseni (P51494) |
| Supervisor: | Abdul Khalim Abdul Rashid, Prof. Madya Ir. Dr. |
| Keywords: | Universiti Kebangsaan Malaysia -- Dissertations Dissertations, Academic -- Malaysia Bridges -- Live loads Bridges -- Design and construction Box girder bridges -- Design and construction |
| Issue Date: | 23-Oct-2013 |
| Description: | The use of multicell box-girder deck in new modern highway bridges has widely increased in recent decades. In spite of all benefits of these bridges, the presence of skewness may raise disputing problems for researchers in determining the static and dynamic responses of these bridges subjected to moving vehicle. Skewed bridges undergo high torsional as well as flexural stresses. The AASHTO LRFD specifications have recommended formulas for the load distribution factors only for moment and shear, and not for stress, deflection and reaction at piers. In addition, these specifications did not consider the effect of diaphragms and continuity in development of recommended formulas. In addition, dynamic impact factor formulas proposed by current specifications are generally restrained to simple supported and straight bridges, obtained from experimental study on limited number of real bridges. Therefore, to meet the practical requirement arising during the design process of skewed multicell box-girder bridges, the simple equations are required to estimate reliable values for live load distribution factor and dynamic impact factor of bridges. In the present study, the three-dimensional finite element program of SAP2000 was used to investigate the static and dynamic behaviour of bridge. Moment and shear distribution factor, fundamental frequencies and mode shapes were compared to experimental and analytical results to verify the modeling technique. Based on up to 1000 rigorous analysis conducted on 280 skewed multicell box-girder bridges, the effect of main parameters on live load distribution factor and dynamic impact factor of bridges were investigated. The results of this study were used to develop the simplified equations for live load distribution factor, skew correction factor and dynamic impact factor of bridges. The finding results indicated that the bridge span length, skew angle, number of boxes and number of lane loaded is the most critical parameters that affect the live load distribution factor of bridges, and intermediate diaphragms extremely affect the live load distribution factor of skewed bridges. Difference between shear and reaction distribution factor were observed. Thus, the skew angle, span length and vehicle speed affect the dynamic response skewed bridges. The dynamic impact factor of moment decreases with the increasing of skew angle, but reaction and shear dynamic impact factors increase. Thus the good agreement between the analytical methods and experimental study verified the accuracy of proposed equations. The results from this study provide an insight into the design of skewed and straight multicell box-girder bridges.,Certification of Master's / Doctoral Thesis" is not vailable |
| Pages: | 192 |
| Call Number: | TG362.M637 2013 3 tesis |
| Publisher: | UKM, Bangi |
| Appears in Collections: | Faculty of Engineering and Built Environment / Fakulti Kejuruteraan dan Alam Bina |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| ukmvital_96537+SOURCE1+SOURCE1.0.PDF Restricted Access | 382.48 kB | Adobe PDF |  View/Open |
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.