The arrangements of cables showing fan, semi fan and harp are shown in following figures. III. ANALYSIS OBJECTIVE

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1 Volume 3, Issue 5, 216 Available online at International Journal of Innovative and Emerging Research in Engineering e-issn: p-issn: Analysis of the behaviour of Cable stayed bridge with different types of cables arrangement Shivanshi a, Pinaki b a Assistant Professor, Department of Structural engineering, CPU, Kota, India b B.Tech. Student, Gurukul Institute of Engineering and Technology, Kota, India ABSTRACT: The Cable Stayed Bridge consists of cables. There are many types of cable arrangements among that we chose fan type, semi fan type and harp type arrangements. The bridge is designed and analyzed for these cables arrangement by STAAD Pro software. The most efficient arrangement is proposed after analysis among three. The comparison is made for Shear force, bending moment, displacements for the cases. The results are summarized and discussed. Then comparisons are made for the three cases. The conclusion is made in respect to the efficiency of one of the arrangements. This can be useful in the modifying the drawbacks of others. This work would give directions to make other arrangements more efficient. Keywords: cable stayed bridge, fan arrangement, semi fan arrangement,harp arrangement, STAAD pro, finite element method I. INTRODUCTION Cable stayed bridges have good stability, optimum use of structural materials, aesthetic, relatively low design and maintenance costs, and efficient structural characteristics. Therefore, this type of bridges are becoming more and more popular and are usually preferred for long span crossings compared to suspension bridges. A cable-stayed bridge consists of one or more towers with cables supporting the bridge deck. In terms of cable arrangements, the most common types of cable stayed bridges are fan, harp, and semi fan bridges. Because of their large size and nonlinear structural behavior, the analysis of these types of bridges is more complicated than conventional bridges. In these bridges, the cables are the main source of nonlinearity. An optimum design of a cable-stayed bridge with minimum cost while achieving strength and serviceability requirements is a challenging task. In this thesis, cable stayed bridge is analyzed by changing he cables arrangement each time, to obtain the results for bending moment, forces, deflection. The three cable s arrangement taken is fan, semi fan and harp arrangement. Comparison between the three types, in terms of forces, bending moment and deflection, is carried out in this thesis. The bridge is analyzed by the commercial finite element based software STAAD Pro. II. LITERATURE REVIEW A typical cable stayed bridge is a deck with one or two pylons erected above the piers in the middle of the span. The cables are attached diagonally to the girder to provide additional supports. The pylons form the primary load-bearing structure in these types of bridges. Large amounts of compression forces are transferred from the deck to the cables to the pylons and into the foundation. The design of the bridge is conducted such that the static horizontal forces resulting from dead load are almost balanced to minimize the height of the pylon. Cable stayed-bridges have a low center of gravity, which makes them efficient in resisting earthquakes. Cable stayed bridges provide outstanding architectural appearance due to their small diameter cables and unique overhead structure [1] The arrangements of cables showing fan, semi fan and harp are shown in following figures. (A) OBJECTIVE III. ANALYSIS In this analysis, the Cable Stayed Bridge is studied for the three types of arrangement of cables i.e., fan type arrangement, semifan arrangement and harp arrangement. The comparison is made for the three types for shear force, bending moment and displacement. The analysis is done by using STAAD Pro software. The most efficient arrangement is proposed after comparison of the three cases. 125

2 Volume 3, Issue 5, 216 Figure 1. A simple illustration of cable-stayed bridge, Figure 2. Arrangements of cables-,semi fan and.[2] (B) PROBLEM STATEMENT 1. Cable stayed bridge with arrangement of cables 2. Cable stayed bridge with Semi- arrangement of cables 3. Cable stayed bridge with arrangement of cables (C) DESCRIPTION OF BRIDGE Analysis is made for cable stayed bridge. The total span of the bridge is 2 m. The total width of the deck of the bridge is 1 m. The diagram of bridge is as shown in Figure.3.In construction; firstly edge beams are erected and then followed by deck slab with crossbeams. The total height of bridge is 65 m. The pylon used here is H shaped. Bridges with arrangement, Semi fan arrangement and harp arrangement are as shown in Figure 4, Figure 5 and Figure 6. The live load, earthquake load, vehicle load are not considered. The thesis is limited to the three cables arrangement only, other are not considered. The properties limited only to the shear force, bending moment and deflections. Other evaluations are not considered. Figure 3. Reference Bridge with dimensions-isometric view (a) 126

3 Volume 3, Issue 5, 216 Figure 4. Cable stayed bridge with arrangement of cables Figure 5. Cable stayed bridge with Semi- arrangement of cables Figure 6. Cable stayed bridge with arrangement of cables 127

4 Volume 3, Issue 5, 216 Comparison Table 1: Max and Min shear forces and bending moment for arrangement Beam Node Fx kn Fy kn Fz kn Mx knm My knm Mz knm Max Fx Max Fy Max Fz Max Mx Max My Max Mz Min Fx Min Fy Min Fz Min Mx Min My Min Mz Table 2: Max and Min shear forces and bending moment for Semi fan arrangement Beam Node Fx kn Fy kn Fz kn Mx knm My knm Mz knm Max Fx Max Fy Max Fz Max Mx Max My Max Mz Min Fx Min Fy Min Fz Min Mx Min My Min Mz Table 3: Max and Min shear forces and bending moment for arrangement Node X mm Y mm Z mm mm Max X Min X Max Y Min Y Max Z Min Z Max rx Min rx Max ry

5 Volume 3, Issue 5, 216 Min ry Max rz Min rz Max Rst Table4: Displacement at nodes for fan arrangement Beam Node Fx kn Fy kn Fz kn Mx knm My knm Mz knm Max Fx Max Fy Max Fz Max Mx Max My Max Mz Min Fx Min Fy Min Fz Min Mx Min My Min Mz Table 5: Displacement at nodes for fan arrangement Node X mm Y mm Z mm Mm Max X Min X Max Y Min Y Max Z Min Z Max rx Min rx Max ry Min ry Max rz Min rz Max Rst Table 6: Displacement at nodes for harp arrangement Node X mm Y mm Z mm mm Max X Min X Max Y Min Y Max Z Min Z Max rx Min rx Max ry Min ry Max rz Min rz Max Rst

6 Volume 3, Issue 5, X mm Y mm Z mm mm Figure 7: At Node 15, Max displacement for, Semi- and, X mm Y mm Z mm mm Figure 8. At Node 15, Min displacement for, Semi- and X mm Y mm Z mm mm Figure 9. At Node 67, Min displacement for, Semi- and X mm Y mm Z mm mm Figure. 1 At Node 1, Min displacement in for, Semi- and. 13

7 Volume 3, Issue 5, X mm Y mm Z mm mm Figure 11. At Node 67, Min displacement for, Semi- and. (A) Beam Shear Forces and Bending moment Fx kn Fy kn Fz kn Figure 12.At Node 11, Shear force for, Semi- and Mx knm My knm Mz knm Figure 13. At Node 8, Bending moment for, Semi- and 131

8 International Journal of Innovative and Emerging Research in Engineering Volume 3, Issue 5, 216 Fx kn Fy kn Fz kn Figure 14. At Node 4, Shear force for, Semi- and Fx kn Fy kn Fz kn 1 Figure 15. At Node 4, Shear force for, Semi- and. 5-5 Mx knm My knm Mz knm -1 Figure 16. At Node 4, Bending moment for, Semi- and. IV. RESULT AND CONCLUSION In this section, the results for the efficient design of the three arrangements of cable-stayed brides including semi-fan, fan, and harp arrangements are presented. The purpose of this to study the effect of different cables configurations on bridge component like pylon, deck, cables, and total cost. The graphical summarized results are as shown: 132

9 15 International Journal of Innovative and Emerging Research in Engineering Volume 3, Issue 5, 216 Deflection 1 5 Deflection semi fan Figure 17. Graph for total Deflection for fan, semi fan and harp type arrangements. 15 Shear Force( in KN) 1 5 Shear Force( in KN) Semi-fan Figure 18. Graph for total Shear force for fan, semi fan and harp type arrangements. 2 Bending Moment(in knm) 15 1 Bending Moment(in knm) 5 Figure 19. Graph for total Bending Moment for fan, semi fan and harp type arrangements. The specific results that can be drawn from this analysis are numerated as follows: 1. The shear force is more in harp than semi fan and least in fan arrangement 2. The bending moment is more in harp than semi fan and least in fan arrangement 133

10 Volume 3, Issue 5, The deflection is more in harp than semi fan and least in fan arrangement CONCLUSION In this study, an implementation of three types of cables arrangement for the design of the cable-stayed bridges have been introduced considering fan,semi fan and harp arrangements. The shear force, bending moment, deflection for three types of cable-stayed bridges are compared with each other and the result of comparisons are reported. First, bridge is developed for fan, semi fan and harp arrangements of cable stayed bridges. Then effect of these arrangements on the stability and efficiency of bridge components are investigated for fan, semi fan and harp arrangements are compared. At the end, the most efficient out of all these three arrangements is proposed. The results indicated that the fan arrangement is more efficient then two other arrangement. ACKNOWLEDGMENT First of all I feel great pleasure in acknowledging my deepest gratitude to my revered guide and mentor, Mr Nitin Nagar, Assistant Professor, Structural Engineering Department, Career Point University, Kota, under whose firm guidance, motivation and vigilant supervision for successful completion of my research work. He infused in to me the enthusiasm to work on this topic. His tolerance nature accepted my shortcomings and he synergized his impeccable knowledge with my curiosity to learn in to this fruitful result. I would also like to thank to entire members of IJIERE for providing me the best platform for presenting the research work. REFERENCES [1] Olfat S.Zadeh (212),Comparison Between Three types of Cable Stayed Bridge using Structural Optimization [2] Aye Nyein Thu, Dr San Yu Khaing Structural Behaviors of Long-span Cable-Stayed Bridge with due to Wind speed,,internatinal Journals of Engineering &Technology,oct 214 [3] Mostafa Salehi, Ahmad Shooshastri,Vahab Esmaili,Alireza Naghavi Riabi. Non-Linear Analysis of Cable Structures under general loading, Finite elements in Analysis and Design,213 [4] On the Structural Analysis and Design of Cable stayed bridge and suspension Bridges,Fabio,marco,Pier Giorgio,International Conference on Bridge maintenance,safety and management, oct 24 [5] Katherina Santoso, Wide Span Cable Structures,University of California,June 22. [6] Krishna,Prem. Cable Suspended Roofs. New York: MacGraw Hill.c