Evaluation and Design of Flyover using Staad pro

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1 Evaluation and Design of Flyover using Staad pro 1 KONDA PRADEEP KUMAR, 2 B.SHANKAR, 3 P.MADHUSUDHAN RAO 1 M. Tech(Structural Engineering), Departent of Civil Engineering, Kouri Pratap Reddy Institute of Technology, Village Ghanapur, Mandal Ghatkesar, District Rangareddy, Telangana, India. 2 Assistant Professor(M.Tech), Departent of Civil Engineering, Kouri Pratap Reddy Institute of Technology, Village Ghanapur, Mandal Ghatkesar, District Rangareddy, Telangana, India. 2 Assistant Professor(M.Tech), Departent of Civil Engineering, Kouri Pratap Reddy Institute of Technology, Village Ghanapur, Mandal Ghatkesar, District Rangareddy, Telangana, India. ABSTRACT- The design of a ain road bridge super structure is critically addicted to standards and criteria. Naturally, the iportance of ain road bridges during a fashionable installation would iply a collection of rigorous style specifications to confir the protection, quality and overall value of the project. In this treatise an endeavor is fored to judge the perforance of skew bridge victiization copletely different skew angles and by victiization grillage analogy ethodology. In India ost of the bridges have a ost span of In recent years as there's treendous growth of traffic and lack of space, thus we tend to area unit adopting skew bridges. In planning skew bridge, in variation of angles we tend to copare the bending oents, shear force. We tend to use Grillage analogy ethodology and style the foreost effective skew bridge by victiization STAAD professional software package. To achieve ain objective of this project a span, RCC bridge by victiization code IRC112:2011 and IRC code for loadings. The results obtained fro this analysis are helpful in planning of skew bridge. The design of a ain road bridge is critically addicted to standards and criteria. Naturally, the iportance of ain road bridges during a fashionable installation would iply a collection of rigorous style specifications to confir the protection, quality and overall value of the project. 1. INTRODUCTION The superstructure for the 22.0 span bridge consists of 6no.s precast pre-stressed concrete girders with 0.15 thick cast in-situ RCC slab above,spaced at centres in the transverse direction. Two end diaphrags are provided without any interediate diaphrag. The concrete grade adopted for the precast girder for the cast in-situ slab is M45. First stage pre-stressing is envisaged in 4 days after casting of pre-cast girders. The second stage prestressing is done on the 14 th day of casting of pre-cast girders or when the concrete attains strength of M40 whichever is later. METHOD OF ANALYSIS: The analysis of the super structure for sharing of B.M and S.F between various girders is done using grillage analysis and coputer odelling is done using STAAD. Bending oent and shear

2 forces are evaluated using the grillage analysis. The B.M due to self weight of girder and B.M due to deck slab weight is done using bea analysis using STAAD Plane. SEQUENCE OF CONSTRUCTION: accoodating any coplexities in the solution. In this ethod, the actual continuu is replaced by an equivalent idealized structure coposed of discrete eleents, referred to as finite eleent, connected together at a nuber of nodes. Behaviour of a skew bridge SPAN ARRANGEMENT: 1. Center to Center of expansion joints = Total length of pre-cast girder = Center to Center of bearings (effective span) = LITERATURE REVIEW Skew bridges analysis using grillage analogy Vikash Khatri et., at (2012) In this paper describes Grillage analysis is the ost coon ethod used in the bridge analysis. In this ethod the deck is represented by an equivalent grillage of beas. The finer grillage esh, provide ore accurate results. It was found that the results obtained fro grillage analysis copared with experients and ore rigorous ethods are accurate enough for design purpose. The finite eleent ethod is a well-known tool for the solution of coplicated structural engineering probles, as it is capable of Dr. Maher Qaqish et., al. (2008) This ethod is usually used for analysis of bridges based on the consideration of the bridge deck as an elastic continuu in the for of an orthogonally anisotropic plate. Using the stiffness ethod of structural analysis, it becae possible to analyse the bridge deck structure as an assebly of elastic structural ebers connected together at discrete nodes. There are four distinct techniques which have been found useful by bridge engineers: grillage and space frae analysis, folded plate ethod, finite eleent ethod and finite strip ethod.the grillage analogy ethod involves a plane grillage of discrete interconnected beas. 3. SKEW BRIDGE ANALYSIS Dead load: The dead load is the weight of the structure and any peranent loads fixed thereon. If the actual calculated dead load exceeds the assued dead load by ore than 2 ½%. Live load: IRC Class AA loading IRC Class 70 R loading IRC Class A loading

3 IRC Class B loading Dead Load of wearing coat = 1.650KN/ 2 Dead Load of Crash Barrier = KN/ 4. METHOD SKEW BRIDGE ANALYSIS DEAD LOAD CALCULATIONS Centroid = = = Self Weight of the Girder Cross sectional area of girder at Mid Span = Load = Cross sectional area of girder at Support = Load = KN/ Unifor weight of Girder = 21.4KN/ Extra weight of girder due to Web thickening Load = (cross sectional area at support cross sectional area at center) 25 = KN/ 5. DESIGN OF TYPICAL TEE-BEAM GIRDER RCC T- BEAM TYPE SUPER STRUCTURES DESIGN: 1. This type of Super Structure involves rigorous analysis of load distribution between longitudinal girders, cross girders and panel slabs. Self Weight of the Deck slab and Diaphrags: Deck slab = 6.000KN/ 2 Weight of End Cross Girder (KN/) = KN/ Weight of Interediate Cross Girder (KN/) = 8.625KN/ Super Iposed Dead Load: 2. We have readyade charts developed by SERC Roorkee for shear force and bending oents at critical points in girders to design steel 3. The SERC Roorkee have also developed design charts bending oents at salient points in slab panels to design steel 4. We can also develop odel in STAAD- pro with bea and slab eleents and analyze with oving loads input. Output gives BM and SF in girders and BM in panel slabs so that the required steel can be calculated.

4 CALCULATIONS FOR SECTIONAL PROPERTIES: SECTIONAL PROPERTIES FOR THE LONGITUDINAL GIRDERS AT THE MID SPAN: 6. DESIGNING DESIGN OF LONGITUDINAL BEAMS C/C of Bearing = Grade of concrete = M45 Grade of steel = Fe500 Suary - Meber properties Dead Load of Slab (250 Thick) Unit weight of concrete = 2.5T/ 3 Unit weight of Wearing coat = 2.4T/ 3 Thickness of slab = 250 END GIRDERS: Length of the Slab ( = 2.75 b = b + = Green Land Junction Flyover c/c of bearings Tabulation of Shear Force and Bending Moent with Ipact: (Ref. clause of IRC: ) Consider least value fro above two UDL = T/

5 MIDDLE GIRDERS: Length of the slab ( ) = 2.5 UDL = ( ) = T/ Support Moent Condition: Maxiu wheel load 70R Wheel load = 26.92KN Self weight of slab = 0.63KN Wearing coat weight = 0.149KN Construction live load = 4.00KN Total UDL = 31.69KN/ Bending oent = 24.76KN Calculation of Tension Reinforceent at botto of the Bea (fro staad output) Calculation of depth: Q = n j = 1.71 Effective depth = = Total depth = Hence ok 3design of end cross girder (end diaphrag): Grade of concrete = M45 Grade of steel = Fe500 Perissible stress in concrete = 15 Perissible stress in steel = 250 Lever ar factor, j = Size of the cross diaphrag Width = 250 Depth = 2430 Effective depth = 2370 M = 24.76KN- σ = 240 j = d = A = Provide 12 dia bars = Area of bar = Spacing of bar = Say = 210

6 Provide 12 TOR bars at 210 C/C at botto Provide 12 TOR bars at 210 C/C at top Distribution steel: Miniu percentage 0.1% of b D = Provide 10 dia bars Area of bar = Spacing of bar = Say = 315 Provide 10 TOR bars at 315 C/C 7. CONCLUSION The Grillage Analogy provided close results to the easured values. The influence of slight variation was very sall, so it was not concern in evaluating load distribution of the bridge. Diaphrags plays ore iportant role in load distribution. After adding diaphrags load distribution factor decreased. At the obtuse corner of the skewed bridge, negative oents appear at the pinned ends due to effect of diaphrags. It plays sae effect on deck. As a result, the effect of end diaphrag ight be considered as an equivalent thickness. It should be noted that the oents at pinned ends of girders ay not be zero. As we are designing a bridge with a skew angle areas, oent of inertia, neutral axis have to be calculated. And finally need to calculate area of steel, percentage of steel that to be provided to keep safe the structure. References [1] Trilok Gupta, Anurag isra (2007), Effect on support reaction of skew bridges, Journal of bridge engineering, ARPN. Vol. 2, No. 1. [2] Shreedhar, R., Rashikharde, (2009), Effect of skew bridge for oving loads, International journal of scientific &engineering research, vol - 4, issue feb-2013, ISSN [3] Vikash Khatri, P.R., Maiti. P.K., Singh and Ansuankar, (2010), Analysis of skew bridge using coputational ethods, /ISSN: , Banaras Hindu University, Varanasi. [4] Maher, Eyad Fadda, Ead Akawwi, (2008), Design of T-bea bridge by finite eleent ethod, (KMITL), Vol.8, No. 1. [5] Arinda Dhar, Mithil Mazuder, Sonath Karkar, (2013), Effect of skew angles on longitudinal girder (shear, oent) and deck slab of an IRC skew bridge, The Indian Concrete Journal. [6] Krishna Raju, N., (2009), Design of bridges, IBM publication, Fourth Edition. [7] Vazirani, V.N, Ratwani, M.M, (2009), Design of Reinforced Concrete structure, Khanna publications, 16th edition, Delhi. [8] Krishna Raju, N., (2013), Pre-stressed Concrete, Mc Graw Hill education, Fifth Edition.