Comparison of design results of a Structure designed using ...

1 INTERNATIONAL JOURNAL OF CIVIL AND STRUCTURAL ENGINEERING. Volume 2, No 3, 2012. Copyright 2010 All rights reserved Integrated Publishing services Research article ISSN 0976 4399. Comparison of design results of a Structure designed using staad and ETABS Software , , , Arpan Herbert4. 1- Higher Degree Student, Civil Engineering Group, Birla Institute of Technology & Science, Pilani- 333031, Rajasthan 2- Assistant Professor, Civil Engineering Group, Institute of Technology & Science, Pilani- 333031, Rajasthan 3- Professor and Associate Head, Department of Civil Engineering, SHIATS (Formerly AAI- DU), Allahabad- 211007, 4- Assistant Professor, Department of Civil Engineering, SHIATS (Formerly AAI-DU), Allahabad- 211007, ABSTRACT.

2 STAADPro and ETABS are the present day leading design softwares in the market. Many design companies use these softwares for their project design purposes. So, this project mainly deals with the comparative analysis of the results obtained from the design of a regular and a plan irregular (as per IS 1893) multi storey building Structure when designed using STAADPro and ETABS softwares separately. These results will also be compared with manual calculations of a sample beam and column of the same Structure designed as per IS. 456. Keywords: Structure design , STAADPro and ETABS. 1. Introduction STAADPro and ETABS are the present day leading design softwares in the market. Many design companies use these softwares for their project design purposes.

3 So, this project mainly deals with the comparative analysis of the results obtained from the design of a multi storey building Structure when designed using STAADPro and ETABS softwares separately. For first case, a 25mx25m 11 storey Structure is modeled using both STAADPro and ETABS. softwares. The height of each storey is taken as 3mts making the total height of the Structure 30mts. Analysis and design of the Structure is done and then the results generated by these softwares are compared and a conclusion is drawn from them. For second case, a 25mx25m 5. storey plan irregular Structure as per IS 1893 is modeled using both STAADPro and ETABS. softwares. The height of each storey is taken as 3mt making the total height of 15mts.

4 design results of both the softwares are compared along with the manual calculations of a sample beam and column designed using IS 456. 2. Problem Definition Case 1. A 25mtx25mt 11 storey multi storey regular Structure is considered for the study. Modeling, analysis and design of the Structure is done separately on both STAADPro and ETABS. software. Plan of the building considered is shown in Figure 1. Received on December, 2011 Published on February 2012 869. Comparison of design results of a Structure designed using staad and ETABS Software , , , Arpan Herbert Figure 1: Plan of the regular Structure considered Table 1: Preliminary Data Length x Width 25x25m No. of storeys 11. Storey height 3m Beam 400x400mm Column 6-11 storeys 650x650mm Column 1-6 storeys 850x850mm Slab thickness 125mm Support conditions Fixed Beam Releases Axial force Loading consideration Loads acting on the Structure are dead load (DL), Live Load (IL) and Earthquake Load (EL).

5 DL: Self weight of the Structure , Floor load and Wall loads LL: Live load 3 is considered SL: Zone: I. Soil type: II. Response reduction factor: 5. Importance factor: 1. Damping: 5%. Time period: sec (calculated as per IS 1893: 2002). International Journal of Civil and Structural Engineering 870. Volume 2 Issue 3 2012. Comparison of design results of a Structure designed using staad and ETABS Software , , , Arpan Herbert results and Discussions results of vertical reactions of a sample node for different loads have been tabled in Table 2. Table 2: Maximum Deflection at the Roof without Shear Wall Loading STAADPro ETABS. DL kN LL kN kN. EQ(along length) kN kN. EQ(along width) kN kN. Similarly, Bending Moment and Shear Force of a sample column is given in Table 3.

6 Table 3: Bending Moment and Shear Force of a sample column Loading Forces STAADPro ETABS. DL Axial force Fx Shear force Fy Shear force Fz BM Mx 0 0. My Mz LL Axial force Fx Shear force Fy Shear force Fz BM Mx 0 0. My Mz EQ(along length) Axial force Fx Shear force Fy Shear force Fz 0 0. BM Mx 0 0. My 0 0. Mz EQ(along width) Axial force Fx Shear force Fy Shear force Fz 0 0. BM Mx 0 0. My 0 0. Mz design results of a sample beam and column by STAADPro and ETABS are given in below Table 4. International Journal of Civil and Structural Engineering 871. Volume 2 Issue 3 2012. Comparison of design results of a Structure designed using staad and ETABS Software , , , Arpan Herbert Table 4: design results of a sample beam and column Section Total reinforcement ( ).

7 STAADPro ETABS. Beam 1131 1048. Column 3380 3380. Case 2. A 25mtx25mt 5 storey multi storey plan irregular Structure as per IS 1893:2002 is considered for the study. Modeling, analysis and design of the Structure is done separately on both STAADPro and ETABS software. Plan of the building considered is shown in Figure 2. Figure 2: Plan of the irregular Structure considered Table 5: Preliminary Data Length x Width 25x25m No. of storeys 5. Storey height 3m Beam along length 300x350mm Beam along width 300x300mm Column 500x500mm Slab thickness 125mm Support conditions Fixed Beam Releases Axial force International Journal of Civil and Structural Engineering 872. Volume 2 Issue 3 2012. Comparison of design results of a Structure designed using staad and ETABS Software , , , Arpan Herbert Loading consideration Loads acting on the Structure are dead load (DL), Live Load (IL) and Earthquake Load (EL).

8 DL: Self weight of the Structure , Floor load and Wall loads LL: Live load 3 is considered SL: Zone: II. Soil type: II. Response reduction factor: 5. Importance factor: 1. Damping: 5%. Time period: sec (calculated as per IS 1893: 2002). Figure 3: Elevation of the irregular Structure considered results and Discussions results of vertical reactions of a sample node for different loads have been tabled in Table 6. Table 6: Maximum Deflection at the Roof without Shear Wall Loading STAADPro ETABS. DL kN kN. LL kN kN. EQ(along length) kN kN. EQ(along width) kN kN. Similarly, Bending Moment and Shear Force of a sample column is given in Table 7. International Journal of Civil and Structural Engineering 873. Volume 2 Issue 3 2012.

9 Comparison of design results of a Structure designed using staad and ETABS Software , , , Arpan Herbert Table 7: Bending Moment and Shear Force of a sample column Loading Forces STAADPro ETABS. DL Axial force Fx Shear force Fy Shear force Fz BM Mx 0 0. My Mz LL Axial force Fx Shear force Fy Shear force Fz BM Mx 0 0. My Mz EQ(along length) Axial force Fx Shear force Fy Shear force Fz BM Mx 0 0. My Mz EQ(along width) Axial force Fx Shear force Fy 0 0. Shear force Fz BM Mx 0 0. My Mz 0 0. design results of a sample beam and column by STAADPro and ETABS are given in below Table 8. Table 8: design results of a sample beam and column Section Total Req. reinforcement ( ). STAADPro ETABS. Beam 1816 1678. Column 2000 2000. design results Comparison of a sample beam and column designed by STAADPro and ETABS with manual calculations are given in below Table 9.

10 Table 9: design results of a sample beam and column Section Total Req. reinforcement ( ). STAADPro ETABS Manual Calculations Beam 1573 1408 1388. Column 2000 2000 2000. International Journal of Civil and Structural Engineering 874. Volume 2 Issue 3 2012. Comparison of design results of a Structure designed using staad and ETABS Software , , , Arpan Herbert 3. Conclusion From the design results of beams, we may conclude that ETABS gave lesser area of required steel as compared to staad PRO. It is found out from previous studies on Comparison of staad results with manual calculations that STAADPro gives conservative design results which is again proved in this study by comparing the results of STAADPro, ETABS and Manual calculations (refer below table).