Case Study. Hong Kong International Airport Baggage System Upgrade

Transcription

1 Case Study Hong Kong International Airport Baggage System Upgrade

2 Introduction The design for the enhancement of the Baggage Handling system at Hong Kong International airport incorporates the baggage handling system works and associated building structure and services modifications. Building Information Modelling (BIM) is required for the co-ordination of the existing and new systems. InteliBuild has been involved in projects doing BIM for Ove Arup & Partners Hong Kong since 2004 and is one of the leading experts in the field of Building Information Modelling in Hong Kong. An Initial Scheme Design report set out the overall design solution for enhancement of the Baggage Handling System within Hong Kong International Airport. The design solution was developed in partnership with the Technical Services & Procurement (TSP) and Terminal operations team within the Airport Authority and incorporates feedback from reviews with the Senior Management Team. The scheme design was developed as a holistic solution considering the overall functionality and performance of the baggage system and operations, including the interaction between individual sub-systems whilst recognising that the works will need to be procured and installed in phases to avoid disruption to the ongoing operations. The design incorporates the baggage handling system works and associated building structure and building services modifications. The existing baggage handling system layout was modified to the new baggage handling system layout so as to meet the future requirements of the Hong Kong Airport Authority.

3 3D Modelling (2D to 3D) The first stage of the BIM process was the conversion of all of the As-Built information, plans elevations, sketches, into the 3D CAD model. (Fig. 3). Fig. 3 : 3D Modelling using As-Built Plans The existing concrete, steel and mechanical structures were modelled in 3D in AutoCAD (Fig. 4). Fig. 4 : 3D model of Existing Steel, Concrete and Mechanical structures

4 Following the initial 3D modelling, during site visits, the designers noticed that some structures at the site were different from those modelled in 3D. This was further checked by looking at the as-built plans from which the 3D models were created from and comparing them to pictures taken from the site. The conclusion was taken that the as-built plans are not up-to-date or were not updated when changes at the site were made either during construction or when structures were added at the site later. A team of surveyors were commissioned to re-survey the site and the survey data was then input into the 3D model for checking and updating of the 3D model. The survey data which were northings and eastings of point locations of ducts and structures was input using a lisp program and was further checked visually in the 3D model to make sure that what is in the 3D model is accurately representing what the site conditions are. The baggage handling system layout, equipment and operational space requirements were also modelled in 3D. These models included the clear space requirements above and below the conveyors, sorters and conveyor bends (see Fig. 5). Fig. 5: 3D model of conveyors with clear space areas also modelled.

5 3D Model Data The baggage handling system equipments such as Primary and Secondary Sorter Units, Vertical Sorter Units, Scanners, Data Scanners, RFID scanners, horizontal ploughs, conveyor bends and conveyors were modelled in AutoCAD using dynamic blocks with attributes (see Fig. 6). It is a requirement that each block includes data in the form of block attributes to be exported to an excel file for the creation of the Equipment Schedule. Fig. 6: 3D model of conveyors and equipments using AutoCAD dynamic blocks with block attributes It was also required that any changes made in the excel file by the design engineers was to be imported back into the 3D model to update the attributes of the blocks in the model. InteliBuild programmers created Visual Basic programs specifically for this purpose. The process of extracting the data from the 3D model layout just requires opening the 3D model in AutoCAD and running the Visual Basic program inside AutoCAD. The program will then look for groupings/blocks with attributes and extract the data/block attributes to an excel file (see Fig. 7). The excel file can then be updated and used to update the data in the 3D model. To update the data in the 3D model, the model is opened in AutoCAD and the Visual Basic program for importing the data is run. The program updates the data in the blocks in the 3D model using the excel file.

6 I Fig.7 : Sample of Excel file extracted Clash Detection The purpose of modelling all of the existing structures was to generate an accurate virtual representation of what is at the actual site. This is where the new baggage handling services layout and the supporting structure will be modelled and inspected so that everything fits into place. The Clash Detective from Navisworks was used for detecting clashes between building components of different services in the 3D model. Clash detection was done on the Baggage Handling Services layout against all structures in the model (see Fig. 10, 11 & 12). Reports were created within Jetstream Navisworks and exported to html format. The whole 3D model was also published to an NWD file using the Publisher of Jetstream from Navisworks for viewing by designers using the free Navisworks Freedom NWD viewer. The published NWD file contains the whole model including the clash reports. (see Fig. 8). Navisworks Freedom allows Designers and Engineers to view real time navigate and walkthrough the 3D model NWD file (see Fig. 9).

7 Fig. 8: Screen capture of NWD file in Navisworks Freedom showing saved clash reports. Fig. 9: Screen capture of walkthrough view in Navisworks Freedom.

8 Fig. 10: Screen capture of clash detected between existing duct and the proposed baggage handling system. Fig. 11: Screen capture of clash detected between existing structure and the proposed baggage handling system.

9 Fig. 12: Screen capture of clash detected between proposed structure and the proposed baggage handling system. Designers and Engineers scheduled weekly design meetings to get the design coordinated, clashes resolved and make sure that all that are involved in the project be updated about changes to be done. Viewing the design in 3D, walking through and navigating inside the virtual environment created provides better interaction with those involved in the design process and is the best way for the Designers and Engineers to have to understand what the potential problems are in the project and resolve them during the Design meetings. Drawing Sheets (3D to 2D) Drawing sheets in 2D CAD are also required for submission to the Airport Authority and Government for approval. Drawing sheets were created in Autodesk Building Systems 2007 (ABS 2007). The ABS 2007 Architectural module has a sectioning feature that allows users to create horizontal (plan) and vertical (elevation) sections from 3D models. The baggage handling system layout provided problems in creating 2D plan drawings since part of the system are double stacked or even triple stacked (conveyors are placed on top of each other in the same line or crossing one another on different levels) in some areas. The solution was placing lines of conveyor blocks with the same level into different layers in AutoCAD (see Fig. 13). 2D plans were created using the horizontal sectioning feature and 2D sections were created using the vertical sectioning feature of ABS 2007 Architectural module. Plans and sections for the different levels were created and also placed into different layers (see Fig. 14). The plans and sections created using ABS 2007 are blocks which can be later updated automatically whenever there are changes in the 3D model.

10 Fig. 13: Screen capture showing stacked conveyors changed to different layers. Fig. 14: Screen capture showing 2D plans and sections created from the 3D model. The drawings containing the 2D plans and sections are then inserted as external references (xref) in the drawing where the drawing sheet will be created (see Fig. 15).

11 Inserting drawings as external references are preferred rather than inserting drawings as blocks to make sure that any changes done in the original or source drawing will automatically be updated in the sheet drawing. Fig. 15: Screen capture showing the contents of the model space of the sheet drawing. In the paper space of the sheet drawing, the actual paper size is selected and title block (provided as standard by the Airport Authority) is inserted. Viewports are created to view the inserted external references in the model space. After creating a viewport or a window to see the contents of the model space, everything in the model space is seen. In paper space, visibility of layers can be manipulated specific to a viewport. Fig. 16 shows different viewports showing different contents by manipulating the visibility of layers. Annotations and dimension texts were added in paper space. Aside from layer control, different visual styles can be set in the viewports in paper space. Since the isometric view in the sheet drawing is actually a view taken from the 3D model it was required that the viewport display for the viewport be set to hidden (hidden line removal for plotting/printing purposes), the other viewports remain in the default 2D wireframe display. Fig. 17 shows the print/plot of the sample sheet drawing where the isometric view was printed with hidden line removal.

12 Fig. 16: Screen capture showing the contents of the paper space of the sheet drawing. Fig. 17: Sample print of the sheet drawing.

13 Drawing File Format Conversion (DWG format to DGN format) Another requirement of the Airport Authority is the conversion of the AutoCAD DWG format file to MicroStation DGN format file with the layering convention provided by the Airport Authority. The problem that was encountered was that the DWG format files were created and saved using AutoCAD 2007 and ABS 2007 while the software to be used for the conversion to DGN format is MicroStation V7 which only recognizes DWG files created by AutoCAD 2004 or older. Due to this difference in software versions the following were done before the conversion from DWG format to DGN format: Conversion of AutoCAD DWG 2007format to AutoCAD DWG 2004 format Exploding blocks created in ABS 2007 that are not recognized by MicroStation V7 Creating new drawings for the different levels of the conveyor layout Updating the external references of the sheet drawings to the newly created drawings MicroStation can read DWG files and save the DWG format files to DGN format (see Fig. 18). A batch script program was created to convert DWG format files to DGN format files and changing the layers into the Airport Authority layering standards. Fig. 18: DWG format file of the sample sheet drawing opened directly in Microstation.