mbeng_dlg.dcl — Moment/Bending Engineering

File: mbeng_dlg.dcl
Version: v3.60
Category: Dialog Definitions
Size: 5.6 KB (170 lines)

Note

Moment Engineering Analysis

Advanced bending moment calculations including redistribution, T-beam analysis, and combined loading effects for comprehensive structural design verification.

Functional Purpose

Moment Engineering - Performs advanced moment analysis including moment redistribution, T-beam capacity, compression steel effects, and combined loading scenarios.

Key Functions:

  1. Moment redistribution (continuous beams/slabs)

  2. T-beam analysis (composite sections)

  3. Compression steel (doubly-reinforced sections)

  4. Combined loading (axial + bending interaction)

  5. Moment envelope (multiple load cases)

User Need

  • Complex loading (multiple load combinations)

  • Continuous structures (moment redistribution benefit)

  • Composite sections (panel + topping)

  • Capacity optimization (use compression steel if needed)

Typical Workflow

1. User selects analysis type:
   • Simple bending
   • Continuous span (redistribution)
   • T-beam (composite)
   • Combined axial + bending
2. User enters parameters:
   • Load cases (dead, live, wind, seismic)
   • Support conditions
   • Section properties
3. System calculates:
   • Moment envelope (max positive/negative)
   • Required reinforcement
   • Capacity with redistribution credit
4. Results: Optimized rebar design

Control Semantics

Analysis Type:

  • atype - Simple, Continuous, T-beam, Combined

Load Cases:

  • dl - Dead load

  • ll - Live load

  • wl - Wind load

  • el - Earthquake load

  • load_factors - ACI load combinations

Section Properties:

  • width, depth, flange_width (if T-beam)

  • rebar_top, rebar_bot - Reinforcement

Output:

  • moment_pos - Maximum positive moment

  • moment_neg - Maximum negative moment

  • required_As_pos, required_As_neg - Required steel

  • redistribution - Moment redistribution percentage (if continuous)

Engineering Calculations

Moment Redistribution

Continuous Slab (ACI 318):

Can reduce negative moments by up to 20% if:
- ? ? 0.50 ?b (under-reinforced)
- Redistribution compensated in positive moment

Example:
Elastic negative moment: -10 kip-ft
Reduced by 20%: -8 kip-ft (design value)
Savings: 2 kip-ft ? less top rebar needed

Positive moment increases: +1 kip-ft (conservatively)
Net benefit: Reduced total reinforcement

T-Beam Capacity

Composite Section:

Panel + 2" topping = T-beam
Flange width = panel width
Web width = panel thickness
Flange depth = topping thickness

Capacity increases ~30-50% vs panel alone
Lower deflections, better crack control

Integration

Called By: Engineering analysis suite, advanced design tools Calls: Moment calculation library, load combination generator

Documentation Metadata

Enhancement Status: ? COMPREHENSIVE - ENHANCED [4/23 v3.60 remaining]

End of Document