Bending Moment Plot
Calculate and visualize bending moment diagrams online. Free tool for engineers and students. Analyze beams, find max moments & shear forces.
The Bending Moment Plot Tool 🧮✨ is an intelligent, interactive beam analysis calculator that helps you calculate and visualize shear force (V) and bending moment (M) distributions for beams under various loading conditions.
Whether you’re analyzing a simply supported beam, cantilever, or continuous structure, this tool transforms mechanical and civil engineering theory into accurate, visual diagrams — making it ideal for engineers, students, and educators who need to understand load behavior, bending stresses, and design safety.
⚙️ Key Features:
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🧱 Instant Bending Moment Calculation:
Computes bending moment (M) and shear force (V) values across the beam using classical beam theory:M(x) = ∫ V(x) dx V(x) = dM/dxwhere
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M = bending moment (N·m or kN·m)
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V = shear force (N or kN)
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x = position along beam (m)
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📊 Interactive Bending Moment & Shear Force Diagrams (BMD + SFD):
Displays clear, color-coded plots for:-
📈 Shear Force vs. Beam Length
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📉 Bending Moment vs. Beam Length
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⚙️ Supports Multiple Beam Types:
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Simply supported beam
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Cantilever beam
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Fixed–fixed beam
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Overhanging beam
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Continuous beam (2 spans)
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🔩 Multiple Load Configurations:
Easily apply and combine:-
Point loads 🟦
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Uniformly distributed loads (UDL) 📏
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Linearly varying (triangular) loads 🔺
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Moments (torques) 🔄
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Custom load positions
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🧮 Mathematically Accurate Equations:
Uses standard bending formulas for each case:Mmax = (F × L) / 4 → Point load at center Mmax = (w × L²) / 8 → UDL over full span Mmax = F × a × b / L → Point load at distance a,b -
📏 Input Flexibility:
Choose units, supports, load positions, and magnitudes. -
🧾 Step-by-Step Derivations:
Shows equilibrium equations, shear transitions, and bending calculations:ΣFy = 0 → RA + RB – F = 0 ΣM = 0 → RA×L – F×x = 0 M(x) = RA×x – F(x–a)✅ Result: Fully derived equations and moment functions.
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📈 Auto-Maximum Detection:
Automatically marks maximum bending moment and shear points on the plots. -
🧰 Supports Material Analysis (Optional):
Combine with moment of inertia (I) and modulus of elasticity (E) to calculate stress (σ = M·y / I) or deflection (δ) at critical points. -
🧠 Dynamic Visualization:
Adjust loads and watch the bending and shear plots update in real time — ideal for understanding structural response intuitively. -
🌍 Fully Unit-Aware:
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Force: N, kN, lb
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Length: m, mm, ft
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Moment: N·m, kN·m, ft·lb
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📱 Responsive Design:
Works perfectly on desktop, tablet, and mobile — for classrooms, sites, or offices. -
🔒 Privacy-Safe:
100% offline; no uploads or data storage.
💡 How It Works (Simplified):
A bending moment represents the internal force that causes a beam to bend under an external load.
The Bending Moment Plot Tool computes these internal moments and shear forces step by step, then visually displays the results as diagrams.
🧮 Fundamental Equations:
1️⃣ For a simply supported beam with a point load at center (P):
Mmax = (P × L) / 4 V = P / 2
2️⃣ For a uniformly distributed load (w):
Mmax = (w × L²) / 8 V = wL / 2
3️⃣ For a cantilever with end load (P):
Mmax = P × L V = P
📘 Example Calculations:
Example 1️⃣ – Simply Supported Beam (Point Load)
P = 20 kN, L = 6 m Mmax = (20 × 6) / 4 = 30 kN·m V = 10 kN at each support
✅ Result: Max bending moment = 30 kN·m at midspan
Example 2️⃣ – Cantilever Beam (End Load)
P = 5 kN, L = 3 m Mmax = 5 × 3 = 15 kN·m V = 5 kN (constant)
✅ Result: Linear moment diagram, triangular shear diagram
Example 3️⃣ – UDL on Simply Supported Beam
w = 3 kN/m, L = 8 m Mmax = (w × L²) / 8 = 24 kN·m Vmax = wL / 2 = 12 kN
✅ Result: Parabolic bending moment curve, linear shear diagram
🧭 Perfect For:
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🏗️ Civil Engineers: Structural beam design, load analysis, moment verification.
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⚙️ Mechanical Engineers: Shaft, frame, and machinery component analysis.
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🎓 Students: Learn statics, strength of materials, and equilibrium visually.
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🧰 Educators: Demonstrate real-time load and moment relationships in class.
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🧾 Architects: Check beam behavior in design layouts.
🔍 Why It’s Valuable:
The Bending Moment Plot Tool brings complex structural theory to life through dynamic, visualized computation.
It helps users:
✅ Understand how different loads affect internal moments.
✅ Design beams that are strong yet material-efficient.
✅ Prevent failure by identifying high-stress regions.
✅ Learn mechanical principles through clear visual feedback.
✅ Optimize load placement for minimal bending.
It’s your digital structural analysis companion — blending simplicity with precision.
🧩 Advanced Options (Optional):
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🧮 Combined Loading: Mix multiple point and distributed loads.
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📈 Moment & Deflection Overlay: View bending moment and deflection on one graph.
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🧾 Support Reaction Solver: Automatically calculate end reactions.
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⚙️ Material Stress Mode: Compute bending stress using
σ = M·y / I. -
🧠 Export Results: Download BMD and SFD charts as PNG or PDF.
🌍 Common Use Cases:
| Beam Type | Load Type | Span (m) | Max Moment (kN·m) | Diagram Shape |
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| Simply Supported | Point Load | 6 | 30 | Triangular |
| Simply Supported | UDL | 8 | 24 | Parabolic |
| Cantilever | End Load | 3 | 15 | Linear |
| Fixed Beam | Center Load | 5 | 15.6 | Curved |
| Overhanging Beam | UDL | 7 | 21 | Irregular |
🧠 Scientific Insight:
The bending moment defines how internal forces resist external loads, maintaining equilibrium.
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High bending moments occur where shear force crosses zero.
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Bending moment shape reveals beam stability, deflection trends, and stress distribution.
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Engineers design to ensure
Mmax < M_allowableto avoid yielding or failure.
Understanding bending moment behavior is essential for safe and efficient structural design.
✨ In Short:
The Bending Moment Plot Tool 📉⚙️ simplifies beam mechanics by turning equations into live visual diagrams. It empowers you to analyze, visualize, and optimize beams for any type of load or support condition — with unmatched clarity.
Analyze. Plot. Strengthen.
With the Bending Moment Plot Calculator, structural behavior becomes visual, accurate, and intuitive. 🧱📈💡





