International Journal of Engineering Trends and Technology (IJETT) Volume 25 Number 3- July 2015

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1 ANALYSIS AND DESIGN OF STEEL CANOPY WITH HOT WELDED PIPES Yaswanth gorantla #1, Dr. B. Panduranga Rao #2, V.Ramesh #3 #1,2,3 Department of Civil Engineering V R Siddhartha Engineering College Vijayawada, India Abstract The objective of this work is to extend the arrival and departure block at Vijayawada airport by suitably matching the existing roof slopes. A suitable arrangement has been finalized for roof trusses (12m span m cantilever truss on East side and 4.00m cantilever on West side) at a spacing of 2.775m. As the requirement of column free area on other side (perpendicular to span of truss) is 16.65m, it is proposed with two piped beams of 16.65m span for arrangement of 12m span trusses. These piped beams will support seven number of 12m span trusses. Suitable arrangement analysis and design of trusses, piped beams, columns and foundation form the core of this thesis..it has been found from the literature survey 1 arrangement with pipe material is the best alternative and accordingly the work has been carried out using STAAD Pro For better performance STAAD Pro results of the truss are compared with ANSYS results and it is found satisfactory. of 3KN will be imposed on the truss. Since the airport is located in Gannavaram i.e. adjacent to Vijayawada which is near to coastal area, importance is given to the wind load in view of the damage caused to the Visakapatnam international airport due to recent disaster: hudhud cyclone. According to Sagar D. Wankhade, Prof. P. S. Pajgade it is clear that Steel Truss Building using pipe section and PEB is found to be economical compared to Steel Truss Building using angle section. As PEB cannot be preferred because the old slope of the existing airport shed should match the new structure and both should be joined together. Structural arrangement: Piped beams, on the 16.65m span, which support the trusses (on 12m span at a spacing of 2.77m ) are supported by piped columns resting on firm foundation. The structural arrangement is shown in figure.1 Keywords STAAD pro; Ansys ; piped truss. I. INTRODUCTION Trusses in general are simple, compound and complex. Simple truss configurations start with basic triangle. Going on adding a dyad (two members with a common joint) to the existing joints an elaborate simple truss can be generated. Two simple trusses can be joined together with a common joint and a member or two simple trusses joined with three non-parallel, non concurrent members a compound truss can be formed. Complex is neither simple nor compound. All the joints in a truss are welded or riveted but, still we can assume the joints are pinned for analysis purpose. This makes an underestimation in strength of material but still an appropriate approach. The proposed work is to increase the floor area of Vijayawada airport terminal temporarily so that it meets the required capacity of people at immigration, arrival and departure lounge to handle the international air traffic. The lounge is divided into five sections, with each section having a column free area of 16.65m x 12.00m center to center with cantilever projections for roof trusses 4m on west side and 1.28m on east side. Hot welded pipes were considered to design the truss elements. The sections considered are PIPE601.0L1 for top and bottom chords; PIPE483.0M for vertical and diagonal members. The pipe sections are jointed using electric arc welding with sufficient thickness. The purlins used are box type 50mmx50mmx4mm and galvanized thin sheet is used as sheeting material to cover the roof truss. Approximately, a load Fig1 (a) Plan Of The Canopy, Single Span structural Arrangement II. ANALYSIS AND DESIGN The analysis and design of the structure is Carried out in four stages: 1. Analysis And Design Of Roof Trusses 2. Analysis And Design Of Piped Beam 3. Analysis And Design Of Piped Column 4. Analysis And Design Of Foundation Fig 1 (b) Arrangement Of Truss ISSN: Page 130

2 A. ANALYSIS AND DESIGN OF ROOF TRUSSES: Analysis and design of purlin is carried out manually. The dead load i.e sheeting weight and the load from the purlin is applied as a nodal load of magnitude 3KN (figure2-a). Based on the location and height of the structure, the wind pressure was calculated from IS875 Part-3, and is found to be- 1.39KN/m 2. From the calculated wind pressure, wind load acting at joints is obtained as 5.5KN and it is applied on the truss at the nodes (figure2-b).the truss is analyzed for the load combinations specified in IS 800.The pipe sections are provided to the members based on the results of analysis and design check carried out using STAAD.pro. Arrangement of piped beam: A rectangle with outer to outer dimensions of 600mm x 750 mm with spacer connections at regular intervals is formed with pipes along with diagonal to make the beam more rigid Figure4. A 12mm thick MS plate arranged over the beam for seating arrangement of truss Figure 4: (a) Arrangement of piped beam Figure 2: (a) Dead load on trussfigure Figure 4: (b) Loading on piped beam Figure2: (b) Wind Load On Truss Top chord and bottom chord- PIPE601.0L1 Vertical and diagonal members - PIPE483.0M B. ANALYSIS AND DESIGN OF PIPED BEAM: From the results of the analysis of roof trusses, obtained from STAAD.pro, the support reactions from the trusses are taken as loads on the piped beams. Shown in Figure3 Figure 4: (C) : Support Reactions from the piped beam. C.ANALYSIS AND DESIGN OF PIPED COLUMN: The support reactions obtained from the piped beam are taken and that load is applied on the piped column. Arrangement of piped column: Figure 3: Support Reactions from the Truss A square with outer to outer dimensions of 600mm x 600 mm with spacer connections at regular intervals is formed with pipes along with ISSN: Page 131

diagonal to make the column to transfer the load coming from the column, effectively to foundation FIGIRE 5. The axial load was obtained as 52.274KN and the lateral load was obtained as 229.

3 diagonal to make the column to transfer the load coming from the column, effectively to foundation FIGIRE 5. The axial load was obtained as KN and the lateral load was obtained as KN from support reactions of piped beam. The piped column is safe for the axial load alone but due to lateral load, the stresses in the bottom portion of the pipes should take additional stress making the column is unsafe. To counter this, the column is encased with 12mm thick MS plate upto half of height and 6mm thick ms plate for the remaining column. The plate is welded along the four edges of the column to make column more stiff and stable.at the bottom the column is bolted to the foundation pedestal. Figure 6 (a) Foundations on east side Figure 5: Column Arrangement And Loading On piped Column D.ANALYSIS AND DESIGN OF FOUNDATION. To effectively transfer the load from the column to the soil, isolated footing with pedestal is designed taking the support reactions from the column. The safe baring capacity of the soil is found to be 8t/m2 from geotechnical investigation. Footings of size 2.7m x 2.7m x0.7m on East side, 3.0m x 3.0m x 0.9m on west side wear considered. The footing dimension is more on west side because of the additional load induced by the 4m cantilever truss projection. The depth of the foundation is taken as 2m from the ground level. Levelling course of 150mm thick Plain cement concrete (P.C.C) of proportion 1:4:8 is provided beneath the foundation. 1m x 1m pedestals are provided with M20 grade concrete embedded with 8No.s- 25mm diameter foundation bolts at a depth of 1m from the top of the pedestal. The foundation bolts are anchored at the end with 100 x100 x10mm anchor plate. Figure 6 (b) Foundations on west side ANALYSIS OF TRUSS USING ANSYS: The same truss which is analyzed and designed in STAAD.pro was considered and modelled using ANSYS software. In the analysis using STAAD pro three load combinations are considered and the design is carried out for the worst load combination. In ANSYS, analysis is considered for two combinations, the first combination is self weight of the structure and the dead load due to purlin. The second combination is dead load and wind load. Wind load is resolved into X and Y component because nodal load perpendicular o the member axis cannot be defined in ANSYS. The minimum and maximum stress for both combination of load is shown in figures below. ISSN: Page 132

In ANSYS, pipe188 element is considered for analysis of pipe truss.

Using key points and lines the truss is created then each element in the truss is meshed with uniform

Support conditions and load conditions are applied to the truss, analysis have been carried out.

Figure 10: Stresses in members for Load Case:1 Load case Stress(N/mm 2 ) Maximum MINIMUM (D.L + L.L) x 1.

4 In ANSYS, pipe188 element is considered for analysis of pipe truss. Sectional properties are defined using pipe sections. Using key points and lines the truss is created then each element in the truss is meshed with uniform divisions. Support conditions and load conditions are applied to the truss, analysis have been carried out. Forces and stress in the members have been obtained. Figure 10: Stresses in members for Load Case:1 Load case Stress(N/mm 2 ) Maximum MINIMUM (D.L + L.L) x (D.L + L.L+W.L)x Table 1: Load Combinations Figure 7: Truss model in ANSYS Figure 8: Properties and Loading for Load Case : 1 Figure 11 : Properties and loading for Load Case :2 Figure 9: Deformation of truss due to Load Case:1 Figure 12: Member forces for Load Case:1 ISSN: Page 133

5 Figure 13: Stresses in members for Load Case:2 Figure 14: Stresses in members for load Case :2 III. CONCLUSIONS 1. The member forces in the truss members when analysied in STAAD.Pro and ANSYS are nearly equal. 2. Member forces in the piped columns at the bottom panel are very high, dueto the application of wind loads.to meet the requirment for high stresses piped columns are encased with M.S plates. 3. Analysis has been carried out in four different stages separately for trusses, piped beams, piped columns and foundations, without giving any interruption to the interaction between pin-joints and rigid joints. 4. Aproxiate structural steel consumption works out to 4.1kg/sft. REFERENCES [1] Sagar D. Wankhade, Prof. P. S. Pajgade, Design & Comparison of Various Types of Industrial Buildings, International Refereed Journal of Engineering and Science, Volume 3, Issue 6 (June 2014). [2] MananD.Maisuri, HiteshK.Dhameliya, Hiten L.Kheni, Review Of Comparison Between Conventional Steel And Tubular Steel Section For Multi Span Industrial Shed With Truss And Portal Frame.Volume 1,Issue 12, December [3] Dr. K. Manjunath, Santhosh Kumar.C.N, Reliability based Analysis of Steel Truss Member, International Journal of Emerging Technology and Advanced Engineering, Volume 2, Issue 11, November 2012 [4] IS 875 (part 3) 1987: Wind Loads. [5] IS Indian standard code of practice for general construction in steel. [6] IS Plain And Reinforced Concrete - Indian standard Code Of Practice. ISSN: Page 134

Analysis and Design of Multi-Storey Building Subjected to Lateral Forces

Analysis and Design of Multi-Storey Building Subjected to Lateral Forces Analysis and Design of MultiStorey Building Subjected to Lateral Forces Pratik Dadsena 1, Nishant Rajoria 2, Bhaskar Dadsena 3 Student, Department of Civil Engineering, S.E.T., Sharda University, Greater