Report on Seminar

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Certificate

Sinhagad Institute of Technology and Science, Narhe, Pune – 411041

Civil Department

Seminar Topic

Reliability of software analysis in structural engineering (RCC)

This is to certify that the report entitled “Reliability of software analysis in structural engineering (RCC)” is a bonafide record of the Seminar presented by

Name – Mr. Nikhil Sunil Kumbhar T.E Civil - Roll No- T5043 Batch – T3

From. Sinhgad Institute of Technology and Science Narhe Ambegaon Pune.

Academic Year – 2013 – 2014

Sign of Seminar Guide (Mr.I.M.Jain)

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2 Civil Dept. Sinhagad Institute of Technology and Science,

Narhe, Pune- 411041

Reliability of software analysis in structural engineering (RCC)

Presented by Mr. Nikhil Sunil Kumbhar ([email protected]) T.E Civil - Roll No- T5043 Batch – T3

Seminar Guide – Mr. I.M.Jain Academic Year – 2013 – 2014 Abstract -

STAAD.Pro, SAP 2000, RSA Pro 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 multi storey building structure and simpe 2D RCC Frame when designed using STAADPro, SAP2000, RSA Pro and ETABS softwares separately. These results will also be compared with manual scalculations of a sample beam and column of the same structure designed as per IS 456.

Keywords: Structure Design, STAADPro v8i, RSA Pro 2014, SAP 2000v 16 and ETABS 2013 1.Introduction

 STAADPro, ETABS, RSA Pro, SAP 2000 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 multi storey building structure when designed using STAAD.Pro ,

ETABS, RSA Pro, and SAP 2000 softwares separately and also determining which one is the most reliable software.

2.Limitations on Manual calculations

 As the size of structure goes on increasing, manual errors in calculations goes on increasing.

 Though the size of structure is small, still time require for designing the structure is more.  Human can do mistake while calculating for complex elements.

 Every time human has to refer the code.  Lack of good presentation of results.  Can not optimize the structure for economy

3.Necessity of Software analysis in structural engineering.  To eliminate the manual calculations and errors.

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 To represent the results obtained in powerful manner  To compare different design criteria for same structure.

 For structural detailing which is the most important part of structural design.  To save the time by reducing time taken for calculations.(almost in secs)  To design the structure as per code of any country.

4.Softwares for structural analysis and design. 1. CSI SAP 2000

2. CSI Etabs 2013

3. Autodesk Robot Structural Anlysis Pro 2014

4. Bentley Staad.Pro v8i 5. SAFE 6. Tekla Structure 19 7. MidasGen 8. Master Series 9. STRAP 10. Bently RAM 11. Axis VM 12. RISA 5.Problem Definitions

5.1Case I - G+2 Storey Structure

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Narhe, Pune- 411041 5.1.1.General Geometry

• Room Size ( C/C) = 3m x 3m • No of Rooms/ Floor = 9 Nos • No of Storey = 3

• Type of Support at base of column = Fixed(Restrained in X,Y,Z) • Floor to Floor Height = 3m

• Type of Structure = RCC

• Beam Size(Typical) = 300mm x 400mm • Column Size(Typical) = 300mm x 300mm • Slab Thickness = 200mm

5.1.2.Property assignments

 Characteristic of Concrete(fck) – 20Mpa (M20)

 Steel Grade – Fe 415 (For main also secondary reinforcement) 5.1.3.Loads

 Dead Load – 1.5 kN/m2  Live Load – 2 kN/m2

 Load Combination – 1.5*(DL + LL) as per IS 456  Load Variation – Linear

 Note – Load values are taken as per IS 875 by considering Residential Project.  Seismic forces are not considered.

5.1.4..Results Table No – 1 Results for Case I

Parameters Staad.Pro Etabs RSA Pro SAP 2000

Live Load Reaction 27.054kN 26.7kN 26.56kN 27.21kN Dead Load Reactions 143.785kN 147.4kN 146.99kN 147.78kN Reactions for Load

Combination(1.5*(DL+LL)

259.188kN 261.15kN 260.32 262.50kN

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Total Moment

(1.5*(DL+LL) at 1.5m

5.38kN.m 7.88kN.m 8.72kN.m 7.89kN.m

Area Provided 339mm2 246mm2 339mm2 246mm2

Design Load Calculated for Column 151kN 135.03kN 142.53kN 136.18kN Area of long-steel in columns 452.39mm2 (Min Requirement as per IS is 720) 720mm2 904.78mm2 720mm2

Staad.Pro do not consider minimum requirement of steel as per Code

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Narhe, Pune- 411041

Fig3- Loading Diagram of 2D RCC Frame 5.2.1General Geometry

• RCC Portal Frame • H = 4m

• Span of beam – 4m each • Beam Size - 400mm x 600mm • Column Size – 400mm x 400mm

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5.2.2Property

 Characteristic of Concrete(fck) – 20Mpa (M20)

 Steel Grade – Fe 415 (For main also secondary reinforcement) 5.2.3.Loads

 Dead Load – 50kN/m (Excluding Self wt)  Live Load – 50kN/m2

 Load Combination – 1.5*(DL + LL) as per IS 456  Load Variation – Linear

 Seismic forces are not considered. 5.2.4Results

Table No – 2 Maximum Moments Max Moments in kN.m

Softwares Left MidSpan End Support

Staad.Pro 56.07 163.15 269.52

RSA Pro 55.67 162.55 273.91

Etabs 56.28 161.59 270.24

SAP2000 56.28 161.59 270.24

Requied Ast analysis(area in mm2)

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Narhe, Pune- 411041

Table No – 3 Area of steel required

Table No – 4 Results for Column

6.Conclusions

• From analysis of Case I and Case II, It has been found that Staad.Pro v8i do not satisfy the minimum requirement of steel for compression member given as per IS Code.

• Also from Case I and II, it is found that Staad.Pro is giving conservative results, whereas Etabs, RSA Pro and SAP are giving closer results compare to Staad.

• From Case I, It is cleared that there is large variation in results when floor load is applied.

RSA Pro 460.43 847.04 1561 Etabs 492 868 1549 SAP2000 492/621(from Sesmic) 867 1549 Mannual Calculations 462 827.9 1531 Design Load 287.44 kN Design Moment 55.67 kN.m

Column Ast Provided Min ast

Staad.Pro 904.78 1280

RSA Pro 1520.53 1280

Etabs 1280 1280

SAP2000 1280 1280

Note - Staad.Pro is giving huge difference in Min ast and Provided Ast (Almost difference of 1 bar of 22mm)

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• For the RCC building structure, Etabs, RSA Pro are the best software packages. • SAP 2000 is also good software but it is designed for general purpose due to which it

lacks in detailing of structure, however results obtained are great and satisfy the requirements of Code.

• Though the each software is good, it is better to check the design in multiple softwares to ensure the reliability of design.

• Hence from design results, we can conclude that RSAPro, Etabs and SAP are the most reliable softwares, whereas results of Staad in Compression reinforcement do not satisfy in some sections.

• From Structural analysis results, we can conclude that all the softwares are reliable excluding floor load analysis.

7. References

• International Journal Of Civil And Structural Engineering Volume II, Issn 0976 – 4399 article by Prashanth.P, Anshuman.S, Pandey.R.K, Arpan Herbert

• IS 456:2000 • IS 875 Links • http://en.wikipedia.org/wiki/List_of_finite_element_software_packages • http://www.engr.usask.ca/classes/CE/463/Labs/CE%20463%20Lab1%202014/CE463_L ab1_2013.pdf • http://www.overstirred.com/2011/09/top-5-structural-design-softwares.html • http://www.designtoeurocodes.com/forums/showthread.php/307-What-is-your-main-structural-analysis-and-design-software Softwares Usied –

 Staad.Pro v8i (structural analysis and design professional)  Etabs 2013 (Extended 3D Analysis of Building Systems)  RSA Pro 2014 (Robot Structural Analysis Professional)

 SAP 2000 v16 (Structural Analysis Programe)(in 1996 first version of SAP with GUI)