PAL

Experiment 6: Non-Linear Analysis of RC Structural Components using ATENA

1. Aim

To perform non-linear analysis of reinforced concrete (RC) structural components using ATENA software and understand the response of RC elements under realistic loading conditions.

2. Objectives

• To familiarize students with ATENA software for structural analysis.
• To model RC beams, slabs, and columns and perform non-linear analysis.
• To interpret software results such as stress distribution, crack formation, and deflection.
• To correlate software analysis with theoretical behavior and observed field defects.
• To encourage hands-on practice using the official ATENA tutorial.

3. Theoretical Background

• Non-linear Analysis: Captures realistic structural behavior, including cracking, crushing, and yielding of RC members.
• ATENA Software: Advanced tool for 2D/3D non-linear analysis of concrete and reinforced concrete structures.
• Capabilities include modeling material non-linearity, reinforcement interaction, crack propagation, and post-peak behavior.
• Students are advised to consult case studies and examples in literature to better understand the practical implications of non-linear analysis.

4. Software Installation & Tutorial

1. Download ATENA Software:

   • Visit Cervenka ATENA Documentation for software instructions.
   • Install the ATENA Engineering 3D trial version on your personal computer or lab workstation.

2. Tutorial Guidance:

   • Follow the official tutorial sheet: ATENA Engineering 3D Tutorial PDF
   • Complete the step-by-step exercises as provided.

3. Practice Tasks:

   • Model a simply supported RC beam and analyze for bending and cracking.
   • Observe stress distribution and crack propagation under increasing load.
   • Record load-deflection curves and compare with theoretical expectations.
   • Document all steps, screenshots, and results in your report.

5. Procedure (Sample – for reference only)

1. Launch ATENA software and create a new project.
2. Define geometry, material properties, and boundary conditions for the RC member.
3. Assign reinforcement details as per design specifications.
4. Apply loads incrementally and perform non-linear analysis.

5. Observe and record results:

   • Crack initiation and propagation
   • Stress distribution in concrete and reinforcement
   • Maximum deflection and failure points
6. Follow the tutorial sheet and note all deviations or observations.
7. Prepare a report including screenshots, interpretation, and comparison with theoretical expectations.

6. Observations & Data Recording (Sample Table – for reference only)

Sr. No.	RC Component	Load Applied	Crack Location / Type	Max Deflection	Observed Stress	Notes / Screenshot Reference
1	Simply supported beam	20 kN	Mid-span flexural	5 mm	28 MPa	Screenshot_01.png
2	Cantilever slab	15 kN	Support region	3 mm	22 MPa	Screenshot_02.png
3	Column under axial + lateral load	50 kN	Local crushing near base	1 mm	35 MPa	Screenshot_03.png

Students must complete a minimum of 3–4 different simulations with screenshots properly captured, numbered, and captioned in the report.

7. Analysis (Sample – for reference only)

• Compare observed crack patterns, deflections, and stresses with theoretical predictions.
• Identify critical regions prone to failure and discuss reinforcement adequacy.
• Discuss how non-linear analysis helps in understanding real-life structural behavior.
• Reference case studies from literature for validation and deeper understanding.

8. Treatment / Preventive Recommendations (Sample – for reference only)

• Reinforcement detailing improvements for areas with high stress concentration.
• Material selection or strengthening methods for critical regions.
• Design modifications based on simulated non-linear response.
• Implement monitoring or additional NDT for in-service structures showing similar behavior.

9. Results (Sample – for reference only)

• Load-deflection curves of simulated RC members.
• Crack pattern and stress distribution diagrams.
• Critical observations from software analysis compared with theory.
• Recommendations for reinforcement or structural improvements.

10. References / Suggested Reading

• ATENA User Manuals (Červenka Consulting)
• ATENA Engineering 3D Tutorial PDF: https://www.cervenka.cz/assets/files/atena-pdf/ATENA-Engineering-3D_Tutorial.pdf
• Selected journal papers on non-linear analysis of RC members

Note: Students can add additional references from textbooks, IS codes, and research articles related to non-linear modeling and analysis.

11. Viva Questions (Sample: for reference only - Do not write in the final report)

1. What is non-linear analysis and why is it important for RC structures?
2. How does ATENA simulate crack propagation and material non-linearity?
3. Explain the significance of load-deflection curves in your analysis.
4. How do your simulation results compare with theoretical predictions?
5. Can non-linear analysis predict failure zones in real structures?
6. What precautions should be taken while modeling RC members in ATENA?

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