ARKON - Infrastructure Management & Engineering

03/06/2026

📊 Modal Analysis Check in ETABS – ACI 318M-19 Compliance

Before proceeding with seismic design, it is essential to verify that the structural model accurately captures the dynamic behavior of the building.

Key checks performed during Modal Analysis:

✅ Translation in X Direction (UX)
✅ Translation in Y Direction (UY)
✅ Rotation about Z Axis (RZ)
✅ Natural Period Verification
✅ Mode Shape Assessment
✅ Mass Participation Ratio Check

Practical Example:
For a G+12 RC Building modeled in ETABS, cumulative mass participation exceeded 90% in both translational directions and rotational mode, satisfying the requirements for dynamic analysis.

A well-defined modal analysis helps engineers:
✔ Predict structural response during earthquakes
✔ Identify torsional irregularities
✔ Validate model stiffness and mass distribution
✔ Improve overall design reliability

Remember: A good design starts with a good analytical model.

03/06/2026

🚀 Static Analysis vs Dynamic Analysis – Are You Choosing the Right Method?

In structural engineering, selecting the appropriate seismic analysis method is critical for achieving safe, code-compliant, and economical designs.

🔹 Static Analysis (Equivalent Lateral Force Method)
✅ Simpler and faster approach
✅ Suitable for regular, low-rise buildings
✅ Considers primarily the fundamental mode of vibration
✅ Ideal for preliminary and code-permitted designs

🔹 Dynamic Analysis (Response Spectrum Analysis)
✅ Considers multiple modes of vibration
✅ Captures higher mode effects and structural irregularities
✅ Provides more realistic force distribution and displacement results
✅ Recommended for taller, complex, and irregular structures

Choosing the right method is essential for safe and efficient structural design👍

28/05/2026

10/05/2026

We are pleased to announce the successful completion of the structural design and detailing works for a 2-Story Family Residence project in Noakhali, developed in collaboration with Plan Architect.

The project was carefully designed to ensure structural safety, functionality, durability, and construction efficiency while meeting modern residential standards. Our scope included comprehensive structural analysis, design, and detailed construction drawings to support smooth project ex*****on.

🏗️ Project: 2-Story Family Residence
📍 Location: Noakhali
🤝 Architectural Partner: Plan Architect
📐 Service Scope: Structural Design & Detailing

We sincerely appreciate the trust and cooperation of our client and project partners. We remain committed to delivering reliable, efficient, and innovative structural engineering solutions for future developments.

06/05/2026

🏗️ ETABS Essentials: Choosing Between Membrane and Shell Elements
When modeling floor systems in ETABS, one decision can significantly influence your results: selecting the right element formulation. Choosing between Membrane and Shell isn’t just a minor setting—it directly impacts how loads flow and how your structure responds under stress.
Here’s a clear breakdown to guide your next project:
🔹 Membrane — The Load Distributor ⚖️
Think of it as a flexible surface with no bending stiffness. It doesn’t resist out-of-plane forces.
✔️ Transfers loads entirely to beams and columns using tributary areas (one-way or two-way).
✔️ Ideal for beam-slab systems where beams are designed to carry the load.
✔️ Commonly used for ribbed slabs, waffle slabs, and steel decking.
💡 Use it when you want a simplified load path and don’t need to design the slab within ETABS.
🔹 Shell — The Structural Backbone 💪
A more comprehensive element that resists bending, shear, and axial forces.
✔️ Distributes loads based on stiffness using finite element analysis (FEA).
✔️ Interacts with the structure by accounting for deformation compatibility.
Types:
• Shell-Thin: Standard choice for most slabs (ignores transverse shear deformation).
• Shell-Thick: Best for thick elements like raft foundations, transfer slabs, and tall buildings where capturing shear deformation—especially in walls—is critical.
✔️ Ideal for flat slabs, shear walls, and complex systems where slab stiffness plays a key structural role.
📌 Bottom line:
If your slab is just a load distributor → go with Membrane.
If it’s part of the structural system → Shell is the way to go.

06/05/2026

We are pleased to announce the successful delivery of the structural analysis and design of a 10-story residential building in Savar, Bangladesh, with an approximate built-up area of 3,900 sft.

🔹 Scope of Services
▪ Structural Analysis & Design
▪ Linear Static Analysis
▪ Comprehensive Structural Detailing

🔹 Advanced Engineering Verification
All analyses and checks were conducted in accordance with BNBC 2020, ASCE, and ACI standards, including:

✔️ Displacement & Inter-story Drift Control
✔️ Seismic Drift Compliance
✔️ Torsional Irregularity Assessment
✔️ Soft & Weak Story Identification
✔️ P-Delta (Second-Order) Effects Analysis
✔️ Mass Irregularity Evaluation
✔️ Re-entrant Corner Effects Check
✔️ Diaphragm Discontinuity Verification
✔️ Structural Eccentricity Assessment
✔️ Base Shear Validation
✔️ Overturning Stability Check

🔹 Engineering Tools & Platforms
ETABS | SAFE | AutoCAD

Through a rigorous analysis and verification process, we ensure structural safety, serviceability, and full compliance with governing codes, delivering optimized and constructible design solutions.

📞 Partner with us for reliable and professional structural engineering consultancy—from concept to completion.