Mezzanine Level Design and Fabrication – 6 O'Connell St, Sydney

1

Executive Summary

project charter overview

Introducing heavy structural modifications into existing commercial high-rises carries major engineering risks, strict building code demands, and tight on-site scheduling limits. For the 6 O'Connell St commercial development, Sydney Welding Engineering required structural fabrication and assembly blueprints designed to fit a pre-defined spatial boundary without error. KEVOS® developed a complete 3D digital twin of the mezzanine in SolidWorks, allowing our engineers to optimize material thickness, detail individual structural parts, and specify exact welding parameters. This exhaustive up-front engineering eliminated fabrication delays, avoided conflicts with strict CBD building codes, and provided onsite installation crews with clear visual assembly instructions to secure a flawless on-time handover.

First Principle

"Verify Virtually, Build Flawlessly"

Physical structural steel cannot be adjusted easily on-site. Resolve every clearance gap, bolt alignment, and weld prep inside the 3D CAD workspace first.

Verify structural members against Sydney's commercial building codes.
Apply parametric CAD modeling to accelerate design generation on tight schedules.
Produce step-by-step visual assembly guides to streamline onsite erection.

2

Visual Knowledge Map

modeling-to-erection lifecycle

Phase A · Design & Sizing

1 site survey dimensions analysis 2 Select load-bearing steel profiles 3 Build master 3D SolidWorks assembly 4 Verify commercial structural code clearances

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Phase B · Shop Detailing

5 · Workshop Drafting

Isolating part drawings, calculating tolerances, and specifying continuous weld maps.

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Phase C · Onsite Erection

6 Run final tolerance stack check 7 Package shop-floor fabrication guides 8 Deliver step-by-step visual assembly maps Result: 100% compliant, zero-rework install

3

Core Concepts

structural fabrication glossary

Concept

Structural Grid Sizing

The engineering layout of columns and primary steel beams mapped to carry commercial occupancy weight loads safely.

Concept

Digital Assembly Twin

A high-fidelity 3D model of all columns, joists, and connection plates to test fit-ups virtually before steel cutting.

Concept

Granular Part Detailing

Isolating and drafting every component individually to guarantee machining precision and simplify workshop fabrication.

Concept

Weld Mapping Specs

Applying precise welding specifications, prep angles, and structural symbols on plans to secure joints against shear forces.

Concept

Parametric Modeling

Linking steel dimensions directly to assembly models, allowing model geometry adjustments to update drawing sheets instantly.

Speeds up drawing deliveries
Guarantees drawing sheet sync

Concept

Commercial Code Compliance

Coordinating structural steel member sizing and connection types with engineers to meet strict city building safety standards.

Concept

Fabrication Instructions

Providing clear, step-by-step guidelines for cutting, reaming, bending, and prepping steel members in the workshop.

Concept

3D Assembly Guides

Exploded 3D pictorial views generated from the SolidWorks model, showing onsite crews exactly how members link together.

4

Frameworks & Models

safety & dynamic spacing models

Model 1

The Structural Validation Split

90% Virtual Assembly Design Verification

10% Onsite Erection

Shifting 90% of structural design, clearance checks, and code verifications to the 3D SolidWorks workspace allowed for a fast, hassle-free 10% on-site assembly cycle.

Model 2

Mezzanine Load & Wear Risks

Column Buckling

Mitigated by using structural column profiles

Connection Shear

Controlled with thick-plate bolt brackets

Deflection sag

Optimized with high-stiffness support joists

Weld Cracking

Prevented using certified continuous welds

Drafting Target: Every joint, weld type, and plate dimension was detailed to secure maximum structural durability.

Model 3

Project Drafting Economics

Comparing Verification Pathways
Design Verification Path	Rework Risk	Relative Design Time
Standard 2D Drafting Only	High (Frequent on-site clashes & corrections)	Baseline (1.0x)
3D SolidWorks Digital Twin	Near Zero (All interferences fixed prior to build)	Highly Optimized (0.6x using automated templates)

Model 4

Parametric Drawing Loop

System Variables: grid dimensions · plate thicknesses · bolt coordinates · deflection limits.

Define SolidWorks Model→ Generate Automated Sheets→ Release Error-Free Pack

Core Asset Value: A highly accurate, compliant structural drawing pack delivered under tight CBD schedules.

5

Process Flow

sequential engineering drafting phases

1

Site Audit

Verify commercial building dimensions and structural limits.

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2

Frame Sizing

Map structural support column coordinates and beam weights.

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3

3D Modeling

Create the complete virtual mezzanine assembly in SolidWorks.

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4

Code Alignment

Review load calculations with engineers to meet Sydney codes.

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5

Shop Detailing

Draft individual cut-plates, columns, and joists in CAD.

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6

Weld Mapping

Specify structural weld preps and symbols across all plans.

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7

Visual Guides

Generate exploded 3D drawings to simplify field assembly.

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8

Site Handover

Deliver compliant drawings to the Sydney Welding team.

6

Relationship Diagram

structural feedback loops

Structural Load Paths→ High-Stiffness Beam Geometry+ High-Tensile Bolted Brackets→ Code Compliance Signoff→ Zero-Rework Shop Fabrication→ Successful CBD Installation

System Balance: Specifying precise welding profiles distributes the load paths evenly across supporting bracket joints, preventing localized metal fatigue under commercial occupancy loads.

7

Dependencies & Interactions

system boundaries

Erection speeds depend on visual assembly guides — exploded 3D drawings help field crews bolt segments together without mistakes.

Structural safety depends on welding specifications — specifying exact weld preps and throat sizes prevents joint failures.

Fabrication precision depends on granular part detailing — isolating each plate and member on independent sheets reduces shop errors.

Permit approvals depend on code compliance checks — verifying designs against Sydney regulations prevents expensive project reworks.

Drawing delivery speed depends on parametric modeling — automated CAD template updates slash lead times on tight schedules.

Base stability depends on anchor bolt layouts — heavy anchor plates transfer structural weight safely into existing foundations.

8

Key Takeaways

essential lessons

Resolve structural clashes early — complete 3D digital models catch assembly conflicts long before cutting steel.
Isolate components to guide machinists — drawing single parts on separate sheets prevents workshop sizing mistakes.
Specify weld profiles with precision — detailed weld callouts are essential to secure continuous load paths.
Automate workflows to hit tight schedules — utilizing parametric CAD linkages speeds up drawing delivery times.

Simplify visual installation maps — providing 3D exploded views helps on-site crews install columns rapidly.
Partner with structural engineers early — coordinating clearances early secures fast commercial building signoffs.
Design for off-site fabrication — planning pre-fabricated bolt-together panels reduces noisy field-welding work.
Verify foundation slab load parameters — matching base plates to slab parameters secures long-term safety.

9

Revision Sheet

high-impact review

60 seccore objective

The Task: Design and draft a safe, compliant commercial mezzanine level for 6 O'Connell St, Sydney.
The Method: Build a full 3D assembly in SolidWorks to check clearances, and map precise welding details.
The Value: Fast washdowns, zero water pooling, and quick on-site assembly times.

5 mintechnical details

Structural Detailing: High-stiffness columns, thick-plate bracket weldments, and heavy concrete anchor plates.
Fabrication Blueprints: Individual, granular part drawings detailing exact cutting coordinates, ream limits, and surface preps.
Welding Rules: Continuous structural weld mapping matching AS/NZS welding codes to secure structural load integrity.
Field Handover: Step-by-step visual installation manuals and orthographic drawings to guide the Sydney Welding field team.

10

Quick Reference Table

specification reference

Engineering Solutions Summary
Structural Part Group	Workshop Drafting Detail	Applied Technical Specification	On-Site Assembly Value
Primary Column Supports	Isolated, individual member drawings	High-stiffness hollow steel profiles with base plates	Carries vertical occupancy loads with zero column drift
Connection Plate brackets	Detailed hole locations and taper limits	Thick steel plate brackets with reamed bolt holes	Ensures exact bolt alignments and quick member connects
Support Joist Welds	Standard welding symbol callouts	Continuous structural welds and specified prep depths	Guarantees joint strength under dynamic movement loads
Erection Crew Package	3D exploded assembly diagrams	Step-by-step pictorial installation blueprints	Speeds up construction on site and avoids alignment errors

11

Frequently Asked Questions

clarifying the design choices

Why is 3D modeling crucial for commercial city projects?

Commercial high-rises have tight space limits and existing services. A 3D digital model allows us to run clash checks and verify clearances, ensuring the steel fits perfectly without needing on-site modifications.

How did the design meet Sydney's building codes?

We worked closely with structural engineers to check beam sizing, joint layouts, and base anchor spacing, ensuring full compliance with commercial building regulations.

What are the benefits of detail drawing individual parts?

Isolating each plate and beam on separate sheets allows workshop machinists to focus on one set of tolerances at a time, lowering scrap rates and fabrication errors.

How do weld map specifications protect joint strength?

By specifying exact weld preps, depths, and symbols, we ensure the welds can handle commercial shear and bending forces without cracking over time.

How did the 3D visual guide speed up site assembly?

Instead of forcing installation crews to interpret complex, overlapping 2D blueprints, the 3D guide provides a clear, step-by-step pictorial roadmap for erection.

Why was parametric design important on this project?

The project had very tight deadlines. Parametric modeling ensured that any change to structural models updated all dependent drawing sheets instantly, keeping our team on schedule.

12

Memory Hooks

structural tags

Model First

Virtual Verification

Fix conflicts in CAD before cutting structural steel.

Clean Welds

Continuous Paths

Specify exact weld profiles to secure joint strength.

One Sheet

Granular Detailing

Isolate parts on independent sheets to prevent shop errors.

Step Maps

Visual Erection

Provide exploded 3D blueprints to speed up site assembly.

13

Practical Applications

industrial use-cases

Target · Buildings

Commercial Mezzanines

Adding lightweight, high-load steel mezzanine platforms safely inside occupied commercial high-rises.

Target · Warehouses

Industrial Storage Decks

Designing heavy-duty steel framing systems to expand floor capacity inside distribution hubs.

Target · Plants

Machinery Access Platforms

Constructing robust, code-compliant walkways and service structures above large processing lines.

Practice · Quality

Digital Clash Auditing

Leveraging CAD modeling to check for spatial clashes before installing pipelines in running plants.

Practice · Safety

Explosive Area Safety

Placing sensitive control boxes and cables outside active hazardous areas during initial design.

Practice · Civil

Foundation Load Checks

Performing weight distribution analyses to ensure concrete slabs safely support heavy tanks.