Traditional Design Methodologies And Bim

Published Date: 02 Nov 2017

CHAPTER 2

Literature Review

Introduction

As previously mentioned in Chapter 1, the aim of this thesis is to explore how implementing and using Building Information Modeling (BIM) as a design tool can impact the project management process. The main aim of chapter 2 is to clearly provide needed background and information to clarify the research subjects and objectives.

This chapter displays BIM definition, difference between traditional design methodologies and BIM, benefits of BIM to several stakeholders such as owner, Architect and consultant, contractors and also explores different applications of BIM.

This chapter displays development of project management, reviews many definitions and concepts of project management, outlines the importance of project management and presents the different project processes.

BIM

Definition of BIM

There is no definite definition of BIM, but we can describe BIM as a computer aided modeling technology which manages and generates building information by means of related processes of producing, analyzing, and communicating building information models (BIM Handbook 2008). Building information models consist of objects and components, each contains information describing what they represents. The building components are attached with parametric data to describe its attributes for use in functions such as work processes. As the model objects are correlated to each other, changing data in any view of the model will update it in all other views in a coordinated way.

BIM may be also viewed according to the following definition from the National Building Information Modeling Standards:

"… a digital representation of physical and functional characteristics of a facility. A BIM is a shared knowledge resource for information about a facility forming a reliable basis for decisions during its lifecycle; defined as existing from earliest conception to demolition." (NBIMS, 2007, p. 21).

There are many misinterpretations concerning BIM according to Jernigan (2008), there are many common and that a way to get an understanding of BIM is to understand what it is not. One of the biggest misconceptions regarding BIM is that it consists of a single model or database. This is not really the case as BIM on the contrary is constituted by multiple linked models and databases.

Building Information Modeling software utilize what are typically referred to parametric databases, in which all aspects of the building design and construction details are linked to one another to simplify building analysis. To elaborate, the building is digitally modeled in three dimensions, such that any modifications to the actual model are automatically updated in all supporting two-dimensional views or camera angles of the model, including not just the exterior elevations, but the floor plans, building sections, and any interior elevations as well. The parametric nature of data storage can possibly provide many potential benefits. BIM is a technology integrated into various computer software applications as a way to potentially improve the processes of design and building documentation, construction, fabrication, and life cycle assessment of buildings. Building Information Modeling is the use and creation of consistent, coordinated, computable information about a building project in design information that need to be used for design decision making, production of high-quality construction documents, predicting building performance, cost estimating, construction planning, and, eventually, for managing and operating the facility (Krygiel and Nies 2008; Autodesk Inc. 2008).

BIM models are not simply graphic tools; they are also databases for information that assist in the drawings and reports automatic generation, schedule simulation, design analysis, facilities management, and more. These benefits assist the building team in making more informed decisions in collaboration among project team members while reducing or eliminating data redundancy, data re-entry, data loss, miscommunication, and translation errors (Bentley Systems Inc. 2008).

Eastman et al. characterizes BIM models as having the following characteristics (Eastman, Teicholz, Sacks and Liston 2008):

Digitally represented building components with intelligent associations among graphic data, parametric rules, and object attributes necessary for project analysis and work processes including quantity takeoff, specifications, and energy analysis.

Consistent and non-redundant data such that changes to object data are reflected in all views of the object.

Coordinated data such that all views of the 3D model are associative

BIM is becoming an increasingly common catch-phrase among software developers when marketing their software. Eastman et al. (2008) stresses the importance of emphasizing information storage and analysis, the "I" of BIM, describing several characteristics of models which are NOT derived from BIM software:

Models only containing graphic visual 3D data without object attribute.

Models with no support of behavior or parametric proportioning and dimensioning.

Models generated from combining multiple 2D CAD reference files.

Models allowing dimensional changes in one view which are not automatically updated in all other views.

Traditional Design Methodologies and BIM

The problem with traditional design methodologies is that the design aspect of the AEC community is traditionally comprised of architects, structural engineers, mechanical engineers, electrical engineers, and a host of other various professionals who work for owners and clients by typically prescribing buildings components as two-dimensional lines in paper format, or more recently, in AutoCAD or other digital software. Even after the transition from the traditional paper media to digital media, these drawings typically occurred in relative isolation from one another in comparison to the manner in which BIM relates the drawings; although tracing paper for physical media and drawing layers for digital media make it possible to view other 2-D drawings as an underlay, it is difficult if not impossible to place every other relevant finalized or in-process drawing, physical or digital, underneath the current drawing in progress. As a result, errors, omissions, inconsistencies, and/or clashes (overlapping building components) can and do occur quite frequently when any given drawing within the architectural documents is incorrect with respect to any other drawing (Eastman et al. 2008).

Building Information Modeling can potentially reduce such error among multiple drawings by uniting multiple aspects of the building design processes into a single database of information. With BIM software, the building is designed in 3-D, or potentially 4-D which considers time related issues of construction sequencing. The 3-D model can then be used to produce high quality 2-D construction drawings. Due the parametric modeling aspect of BIM, efficiencies are introduced which could expedite the design process (Eastman et al. 2008).

To start designing a building and during preliminary design phase, rough drawings and sketch models are produced to explore architectural concepts such as building mass/void, exterior/interior views, materiality, lighting, color, etc. It is through a series of iterations which the process of building conceptualization progresses such as multiple conceptual physical models might be built in order to explore design possibilities and programmatic requirements of the building, then a separate 3-D digital model might then be produced to assist in fine-tuning of the design and to provide a presentation medium for the owner, investors, and other parties. Ultimately, the architect will use a variety of tools which will be used to generate the final design, and finally the construction documents, which are typically generated as a series of lines printed in traditional 2-D CAD or similar software. Historically, it has been unlikely that these multiple phases in the design process occurred within the same platform. (Krygiel and Nies 2008).

BIM can provide powerful methods of consolidating the phases of the architectural design, even at an extremely preliminary design phase. When the concept of BIM was originally introduced, it predicted the ability of a single building model to support all aspects of design, construction, and operations (Khemlani 2006).

By using Building Information Modeling an effective communication and collaboration can be achieved by specifying data exchange patterns between multiple building product models. This can be achieved through interoperability, which describes the need to pass data between software applications to enable the contribution of different participants and applications to building model data. New patterns of communication of design knowledge and intent have emerged in architectural practice with the implementation of these data exchange routines. This will affect how different design team members express and transfer important design information and the reasoning behind design decisions.