bim curriculum12 lecture 06 construction coordination

BIM Curriculum Lecture Notes 1

BIM Curriculum Lecture Notes

2 BIM Curriculum Lecture Notes

GraphisoftVisit the Graphisoft website at http://www.graphisoft.com for local distributor and product availability information.BIM Curriculum Lecture NotesCopyright © 2009 by Graphisoft, all rights reserved. Reproduction, paraphrasing or translation without express prior written permission is strictly prohibited.TrademarksArchiCAD®, Virtual Building™ and Virtual Building Solutions™ are trademarks of Graphisoft.All other trademarks are the property of their respective holders.

http://www.graphisoft.com

http://www.graphisoft.com

BIM Lecture 6: Construction Coordination

BIM LECTURE 6: CONSTRUCTION COORDINATION

Topics• Problems of the Construction Industry• Objectives• The Virtual Construction Model• BenefitsThe construction industry has been struggling with several difficulties in recent years. Up to 25% of the cost of a construction project is still wasted. In North America, construction is the only non-agricultural industry that has seen a consistent decline in productivity over the past 40 years. Let’s look at how BIM, allied with automated construction coordination solutions, can help to overcome these difficulties.

PROBLEM DEFINITION

Problems of the construction industry affect all areas of the construction process, including the design, subcontractor costs, construction and facility management. Here we list only the most critical of these issues.Design

• No direct cost feedback on design decisions• Coordination of tradesSubcontractor Cost

• Missing / Incorrect Design Information• Inability to reuse data for shop drawings• Field rework required for prefabricated components• Padding to compensate for risks• Poor subcontractor work flow – “Starts and Stops”• Inadequate quantity information for planningConstruction

• Lack of owner trust – difficulties in communicating cost and schedule issues• Production control is based on subjective information • Frequent starts and stops• Estimating is time-consuming and occasionally inaccurateFacility Management

• Insufficient as-built project documentation • Renovation, addition and demolition planning is time-consuming

OBJECTIVES

The needs and the point of view of construction companies are different from those of the architects. Construction must excel in two areas: winning bids and effectively managing the money, manpower, machinery, and materials required to construct buildings. If construction processes and results can be predicted more accurately, that means better business for construction firms.



Objectives

• Winning the bid– Fast design feedback loop– Fast & accurate estimates– Value engineering– Constructability analysis

• Managing the 4 Ms– Money– Manpower– Machinery– Materials

CONSTRUCTION PLANNING

Applying automated construction coordination solutions for construction planning offers significant advantages during the modeling, estimating, sequencing, procurement and site management phase as listed below

Model

• Constructability Analysis• Drives Estimating• Provides Locations• Zone Planning• Design to Build/Build to DesignEstimating

• Fast & Accurate• Easy Updates - Linked• Drives SequencingSequencing

• Schedule Analysis• Line of Balance• Integrated Monte Carlo • 4D Simulation



• Drives ProcurementProcurement

• Data Mining for Supplier Negotiations• Tracking of High Risk, Long Lead Items• Integrated with the Project Schedule• Drives Site Management ProcessSite Management

• Short Lead Procurement• Site Planning for Materials, Equipment and Locations

TRADITIONAL DESIGN PROCESS

The traditional design process lacks any automated project coordination solutions. Several project reworkings are required during the different project phases.

NEW DESIGN PROCESS

The suggested new design workflow is based on the close integration of the BIM model and the construction coordination application. This highly efficient approach supports the iterative design process and minimizes the need for project rework.

THE VIRTUAL CONSTRUCTION MODEL (5D)The building model provides the only logical connection point for cost and time. It elaborates on the ability to predict changes in cost and (to a lesser extent) schedule that would result from lengthening a wall in a model. Neither the schedule nor the estimate as a connection point would provide this type of predictability.



However, the difficult task is to provide a connection that doesn’t change the level of detail existing team members currently use. Estimators, schedulers and other team members manipulate information in very different ways. Graphisoft’s 5D solution has solved this problem in the following way. The next slide describes the information flow.

5D WORK FLOW

The 5D model serves as the bases for all elements of the project control including constructability analysis, cost estimation and construction documentation.

CONSTRUCTION MODELING

The construction modeling process is somewhat different from those in architectural modeling. The following image illustrates the basic conceptual differences between the two approaches. Since the construction model is primarily used to extract quantities for estimating and to identify any possible constructability problems, it is critical that the construction elements are modeled precisely and with correct connections.On the other hand, non-construction elements like furniture or landscape objects that are standard parts of any architectural documentation are not required in the construction model.

The slide shows the construction model of a recessed slab structure. The very same structure is typically modeled with just one plain slab element in the architectural model.



RECIPES

Let’s see how complex elements are modeled in Graphisoft’s 5D solution. A single model object, such as a column, is connected to estimating recipes that describes the methods and resources used to build them.

METHODS

Each recipe stores a series of methods. Most building objects are built at multiple stages. Again using the column as an example, a column is not built at one time. The rebar for a series of columns is built and then the crew returns to place the formwork, and again to pour the concrete, and again for the finishing. Each method represents a separated work activity.

RESOURCES

Each method requires a series of resources. For example, the concrete pour for the column requires:• Equipment• Concrete Mixer• Crane• Materials



• Cement• Sand• Labor

THE 5D MODEL

Because the recipes are divided into methods and the model into zones, a schedule can be extracted based on data on • how many activities are performed on each object • the group of objects on which an activity will be repeated before the next type of activity begins.Once the schedule is updated to reflect actual start times and durations, a full 5D model exists, while still allowing the estimating and scheduler to work at their normal level of detail.

On the following slides we’ll have a quick overview of the main advantages of the Virtual Construction Solution.

BENEFITS: CLASH DETECTION

BIM and construction coordination applications, in collaboration with collision detection tools like NavisWorks, are able to provide automatic clash detection within the structural components, saving as much as 10% in construction costs.



BENEFITS: COST VARIANCES

The ability to change basic parameters of structural elements (like size or material) is a core feature of any BIM application. In addition, the 5D model allows you to estimate the costs of various design alternatives. However, the limitation of cost estimating in the early design phase is that the estimator can work only with cost ranges instead of fixed prizes.

VARIANCE ESTIMATING©The Graphisoft 5D method offers a solution for this problem by assigning cost ranges to the building elements. Consequently, cost variances can be estimated even at the very early design phase of the project.



BENEFITS: DESIGN TO BUILD

A clear benefit of connecting the BIM model with construction coordination applications is that the building design will follow the construction methodology from its earliest stages.

BENEFITS: BUILD TO DESIGN

Another consequence of adopting the virtual construction model is that the building can be built more precisely on its site, in accordance with the construction documentation set.

VIRTUAL CONSTRUCTION™ PRODUCTS

Graphisoft’s suite of Virtual ConstructionTM applications and services is helping construction companies to get more business and change the face of the industry.


bim curriculum12 lecture 06 construction coordination

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