BIM

BIMBuilding Information Modeling

What, Who, Where, When, Why, and How?

What is BIM?

BIM Definition: A modeling technology and associated set of process to produce, communicate, and analyze building models. Building models are characterized by:

•Building components that are represented with intelligent digital representations (objects) that ‘know’ what they are, and can be associated with computable graphic and data attributes and parametric rules.

•Components that include data that describe how they behave, as needed for analyses and work processes, e.g., takeoff, specification, and energy analysis.

•Consistent and non-redundant data such that changes to component data and represented in all views of the component.

•Coordinated data such that all views of a model are represented in a coordinated way.

Mortenson’s Definition of BIM Technology

BIM has its roots in computer-aided design research from decades ago, yet it still has no single, widely-accepted definition. We at the M.A. Mortenson Company think of it as “an intelligent simulation of architecture.” To enable us to achieve integrated delivery, this simulation must exhibit six key characteristics. It must be:

•Digital•Spatial (3D)•Measurable•Comprehensive•Accessible•Durable

Definition of Parametric Objects

The concept of parametric objects is central to understanding BIM and its differentiation from traditional 2D objects. Parametric BIM objects are defined as follows:

•Associated data and rules•Non-redundantly•Automatically modify associated geometries•Different level of aggregation•Object feasibility•Link to or receive, broadcast or export sets of attributes

What Can BIM Do?

3D Model

Estimating

Site Coordination

Scheduling and Animation

Construction Model

Design Review

Who Use BIM, For What, and Benefits of BIM?

•Architect, Designers, and Engineers: • Space planning and program compliance• Energy (environmental analysis)• Design configuration/scenario planning• Building system analysis/simulation• Design communication/review• Quantity take-off and cost estimation• Design coordination (clash detection)

•Benefits:• Ensure project requirements are met• Improve sustainability and energy efficiencies• Design quality communication• Building performance and quality• Communication• More reliable and accurate estimates• Reduce field errors and reduce construction costs

Who Use BIM, For What, and Benefits of BIM?

•Contractor and Estimator:• Quantity take-off and cost estimation• Design coordination (clash detection)

•Benefits:• More reliable and accurate estimates• Reduce field errors and reduce construction costs

•Contractors, Scheduler, and Fabricators:• Schedule simulation/4D• Project controls• Pre-fabrication

•Benefits:• Communicate schedule visually• Track project activities• Reduce onsite labor and improve design quality

Who Use BIM, For What, and Benefits of BIM?

•Owner:• Pro forma analysis• Operation simulation• Asset management

•Benefits:• Improve cost reliability• Building performance and maintainability• Facility and asset management

•Construction Manager•Subcontractor•Manufacturer Supplier•Facility Users•Facility Managers

Where is Bim Use?

When Is BIM Use?

Project Initiation100% Schematic100% Design Development100% Construction DocumentProject Complete

Why Use BIM?

How BIM is Done?

BIM Tools

• Revit• Bentley Systems• ArchiCAD• Digital Project• AutoCAD-based Application• Tekla Structures• DProfiler

BIM Tools (Revit)

•Revit• Introduce by Autodesk in 2002• Leader for the use in BIM• gbXML interface for energy simulation and load analysis• Direct interface to ROBOT and RISA structural analysis• Conceptual design tool• 2D section of detailing• View interface: DGN, DWG, DWF, DXF, IFC, SAT, SKP, AVI, ODBC, gbXML, BMP,

JPG, TGA, TIF•Strength:• Functionality is well-design and user-friendly• Broad set of object libraries• Direct link interface• Bi-directional drawing

•Weakness:• Slow down on project larger than 200MB• Limitation on parametric rules with angles

BIM Tools (Bentley Systems)

•Bentley Systems• Introduce in 2004 by Bentley Architecture• Integrated with others Bentley software

•Strength:• Broad range of building tools• Supports modeling with complex curved surfaces• Multiple support for custom parametric objects• Provide scalable support for large projects

•Weakness:• Large and non-integrated user interface• Hard to learn and navigate• Less extensive object libraries

BIM Tools (ArchiCAD)

•ArchiCAD• Produce by Graphisoft in early 80’s• Serve MAC platform in addition to Windows• Support range of direct interface• Contains extensive object libraries• Suite interfaces for energy and sustainability• OBDC interface

•Strength:• Intuitive interface and relatively simple to use• Large object libraries• Rich suite in supporting applications in

construction facility management• Only strong BIM product for MAC

•Weakness:• Limitation to parametric modeling• Encounter scaling problem with large project• Partition large project to manage them

BIM Tools (Digital Project)

•Digital Project• Develop by Gehry Technologies• Require a powerful workstation to run well• Able to handle even the largest projects• Model any type of surfaces• Support elaborate custom parametric objects

•Strength:• Complete parametric modeling capabilities for

controlling surfaces and assemblies• Relies on 3D parametric modeling for most detailing

•Weakness:• Steep learning curve• Complex user interface• High initial cost• Limited object libraries (including external)• Architectural drawing are not well developed• Output section to drafting systems for completion

BIM Tools (AutoCAD-based Application)

•AutoCAD-based Application• Architectural Desktop ( ADT)• Autodesk original 3D building modeling

tool prior to Revit• Provide a transition for 2D to BIM• Relies on AutoCAD well-known

capabilities for drawing production•Interface: DGN, DWG, DWF, DXF, and IFC•Strength:• Easy to adopt for AutoCAD user• Drafting functionality and interface

•Weakness:• Not parametric modeling• Limited interface to other applications• Scaling problem

BIM Tools (Tekla Structures)

•Tekla Structures• Offered by Tekla Corp.• Multiple divisions: building and construction, infrastructure and energy• Support fabrication-level detailing of precast concrete structure and

facades• Structural analysis• Interface: IFC, DWG, CIS/2 DTSV, SNDF, DGN, and DXF• Export CNC

•Strength:• Model structures that incorporate all kinds of structural materials• Support very large model• Concurrent operations on some projects• Multiple simultaneous users• Support complex parametric custom component libraries

•Weakness:• Too complex to learn and fully utilize• Parametric component require sophisticated operators with high skill• Not able to import complex multi-curved surfaces• Relatively expensive

BIM Tools (Dprofiler)

•Dprofiler• Product of Beck Technologies in Dallas, Texas• Provide feedback for construction cost and time• User gain a set of drawing with financial and schedule

reporting• Can input own cost data or data from RS Means• Support Sketchup and DWG• Interface with Excel and DWG

•Strength:• Market as a closed system for feasibility studies before

actual design begins• Ability to generate quick economic assessments

•Weakness:• Not a general purpose of BIM tool• Purpose is economic evaluation of construction project• Interface to support development in BIM• Design tools is limited to 2D DWG files

BIM Tools

•AutoCAD-based Application• Strength:• Weakness:

•Tekla Structures• Strength:• Weakness:

•DProfiler• Strength:• Weakness:

What is Not BIM Tools

•Models that contain 3D data only and no object attributes

•Models with no support of behavior

•Models that are composed of multiple 2D CAD reference files that must be combined to define the building

•Models that allow changes to dimensions in one view that are not automatically reflected in other views

BIM Facts/Case Study

BIM Terms

Authoritative Standard: A data Standard considered the authority for that type of data. It is usually managed by an association that has as its charter sustaining that data. Authoritative data is data required in the BIM process and must have a point of reference for data fidelity and validity in a BIM product. UniFormat and OmniClass are examples of authoritative standards proposed for NBIM Standard data.

buildingSMART: Created to spearhead technical, political, and financial support for advanced digital technology in the real property industry – from concept, design and construction through operations and management – the new buildingSMART Alliance operates within the independent nonprofit National Institute of Building Sciences (NIBS)

Building Lifecycle Interoperable Software (BLIS): A project of IAI-International, BLIS Project was conceived as a way to initiate the next logical phase in the widespread adoption of an object data model standard for the AEC/FM industry. Through implementation and cooperation commitment by a large number of software vendors the project has a goal of removing the ‘wait and see’ delays in implementing IFC-based software. http://blis-project.org/

BIM Terms

Business Process Modeling Notation (BPMN): a process and graphic notation conventions used to design and capture existing business processes, as well as the simulation of new ones. BPMN is used requirement definition and the Model View Definition processes.

CIMsteel Integration Standards Release 2: Second Edition (CSI/2): Published by The Steel Construction Institute CIMsteel Integration Standards (CIS/2.1), a set of formal computing specifications that allow software vendors to make their engineering applications mutually compatible. http://www.cis2.org/

Construction Specifications Institute (CSI): CSI is a national association dedicated to creating standards and formats to improve construction documents and project delivery. The organization is unique in the industry in that its members are a cross section of specifiers, architects, engineers, contractors and building materials suppliers. www.csinet.org

Harmonization: Comparison and normalization of two or more similar standards including issues such as scope, specifications, guidance or implementation.

BIM Terms

IFCxml: xml which has been developed to map to the IFC data model. http://www.iai-international.org/Model/IFC(ifcXML)Specs.html

Information Value-Chain: As with other industries, and information value-chain needs to be developed around well understood workflows in order to have a collaborative enviroment, the incorporation of NBIMS into software applications supports this value-chain development.

Industry Foundation Dictionary (IFD): Created by IAI-International, this international construction thesaurus currently supporting several languages. CSI in managing this activity in the US. It is used to support various NBIMS Initiative activities. http://ifd-library.com/

Leadership in Energy and Environmental Design (LEED): An initiative of the U.S. Green Buildings Council. www.usgbc.org/leed

BIM Terms

Roadmaps: The overall implementation strategy documents from various groups used to set the definition, direction, sequence and usually milestones for an initiative. For example, the FIATECH Capital Facilities Technology Roadmap. http://www.fiatech.org/projects/roadmap/cptri.htm

Owner/Architect/Engineer/Contractor/ (OAEC or A/E/C/O): Common term used to describe as a group the principal actors/stakeholders during buildings design and construction projects.

Formats

Image (raster) Formats (JPG, GIF, TIF, BMP, PIC, PNG, RAW, TGA, RLE)Raster formats vary in terms of compactness, number of possible colors per pixel, some compress with some data loss.

2D Vector Formats (DXF, DWG, AI, CGM, EMF, IGS, WMF, DGN)Vector formats vary regarding compactness, line widths and pattern control, color, layering and types of curves supported.

3D Surface and Shape Formats (3DS, WRL, STL, IGS, SAT, DXF, DWG, OBJ, DGN, PDF(3D), XGL, DWF, U3D, IPT, PTS)3D surface and shape formats vary according to the types of surfaces and edges represented, whether they represent surfaces and/or solids, any material properties of the shape (color, image bitmap, texture map) or viewpoint information.

3D Object Exchange Formats (STP, EXP, CIS/2)Product data model formats represent geometry according to the 2D and 3D represented. They also carry object properties and relations between objects.

Formats

Game Formats (RWQ, X, GOF, FACT)Game file formats vary according to the types of surfaces, whether they carry hierarchical structure, types of material properties, texture and bump map parameters, animation and skinning. (RWQ, X, GOF, FACT)

GIS formats (SHP, SHX, DBF, DEM, NED)Geographical information systems formats

XML Formats (AecXML, Obix, AEX, bcXML, AGCxml)XML schemas developed for the exchange of building data. They vary according to the information exchanges and the workflows supported.

BIM Sources

Online Sources

Hardin, Brad (2009). BIM and Construction Management PROVEN TOOLS, METHODS, AND WORKFLOWS. Indianapolis, ID, Wiley Publishing, Inc.

Eastman, Chuck, et. al. (2008). BIM Handbook A Guide to Building Information Modeling for Owners, Managers, Designers, Engineers, and Contractors. Hoboken, NJ, John Wiley & Sons, Inc.