Slide 1

An overview of utilizing Revit in a collaborative approach to facilitate a major Expansion and Seismic Retrofit of a complex existing Legacy Building from the 1986 Worlds Fair. Modeling new life into a local landmark

Slide 2

Original podium base structure and 47 metre high geodesic dome constructed in 1984-85 The dome shape, familiar at many World Expositions, meant to symbolize our planet Originally designed as a temporary structure to be the Preview Centre for the Expo 86 Worlds Fair which commemorated Vancouvers 100 th Anniversary and symbolized Vancouvers transportation and communications history

Slide 3

During Expo 86 the facility was a theatre and a gallery for the display of futuristic technology. Expo 86 was the largest international event in Vancouvers history. When facility was transformed into Science World in 1988 Bush, Bohlman & Partners were the structural engineers for expansion and extensive renovations

Slide 4

Since first expansion in 1988, BBP have worked on more than a dozen renovation and exhibit projects including exhibit hall mezzanines, rotunda infill and entry lobby infill Prepared structural report for Facility Renewal Master Plan in 2009, assessment for 2010 Olympics Russia Pavilion, engineering services for Phase 1 of Facility Renewal Master Plan in 2011 and a condition assessment study and report in 2014

Slide 5

Seismic assessment and retrofit of original Expo building (podium structure) utilizing 3D dynamic analysis 2 storey plus accessible roof terrace expansion on west side (facing False Creek) to replace existing terraced faade, replace and rebuild existing exit stairs on west side of facility Modify and rework existing entrance on east side of facility (facing along Quebec Street)

Slide 6

Modifications to existing 1988 building expansion including addition of new freight elevator (for moving exhibits between levels to gallery space) and new steel feature stair through existing Level 2 concrete slab/slab band structure plus various interior renovations. Create a digital 3D model utilizing Revit Structure in a collaborative environment, phased to incorporate the as-built existing structure, proposed selected major demolition and the new expansion, seismic upgrade and structural renovations. Revit Structure model to be used primarily for effective integrated design and coordination with the existing complex structure as well as design visualization and construction.

Slide 7

Original 1984 Expo building and 1988 Science World Expansion drawings are hand drafted with base building geometry established on a circular gridline system Complex and congested existing pile supported foundations with battered piles at major column support locations Geodesic dome comprised of inner dome framed with W-shaped steel members supporting triangular mirrored stainless steel panels and outer exoskeleton of steel tube trusses.

Slide 8

Canon Design modeled grids, levels and generic floors/columns and imported in structural Dome link modeled in Shanghai office by creating curtain grid based on existing drawings and utilizing mass and curtain system. This work turned over to BBP as LOD 200 model BBP took ownership of imported generic data and accurately modeled (to LOD 300) existing building structural components, incorporating all major additions and renovations and linked dome model. Shell model of core and architectural components created and linked into structural model Architectural Cladding model linked to layout changes and modifications to building envelope requiring structural input no duplication of structural elements occurred.

Slide 9

Analytical model exported (with limited success - podium structure, gridlines and levels. Dome modeled non-structural and not exported) and imported in ETabs for analysis. Structural areas to be demolished modeled and phased into Revit Structure model Revit model facilitated installation of new pile foundations relative to existing dome structure

Slide 10

Seismic Retrofit of the existing Expo building podium structure was established utilizing large steel moment resisting frames centered along existing radial gridlines on the west face. The frames are anchored by custom cruciform shape wide flange columns, a BBP trademark used extensively at YVR and at Lynden Pindling Airport in Nassau Bahamas. A parametric Revit structural column family was specially created to facilitate this specific purpose The steel columns are supported by the new pilecaps keyed into the existing concourse level such that no addition gravity or seismic loads were transferred back to the existing structure.

Slide 11

West Expansion followed existing grid layout and framing, infilling demolished terraced faade, incorporating the seismic moment frames and replacing existing pre-cast stair cores Architectural shell model linked to layout East renovations, selective demolition, reworking of existing seismic elements and interior renovations requiring structural input. Architectural Cladding model linked to layout changes and modifications to building envelope and existing structural elements incorporated into new steel structure

Slide 12

Completed Expansion/Renovation model re-visited to facilitate comprehensive Structural report for condition assessment of the existing pile structure and support elements of the inner dome steel frame support structure. Revit structure model upgraded to take advantage of Revit Structure software product enhancements, new features and advanced modeling tools Parameter added to existing pile caps/pile schedule to include category for condition assessment so that all piles could be visibly reviewed and itemized by each steel piles condition status to be tracked and itemized in updated pile schedule. Required extensive visual study of the underside of the existing base structure from a small boat at low tide. Study revealed the damaging effects of salt water on the existing piles and categorized to create a condition assessment for proposed remediation

Slide 13

The original dome linked model first created in 2010 needed to be re-visited and re- modeled to provide a more accurate structural representation of the inner dome steel frame and the outer dome tubular frame, particularly at the connection nodes which were the main focus of the dome condition assessment. Various options for creating a realistic and useful structural model of the domes were explored including Conceptual Mass Environment, Adaptive Components as well as Dynamo, tools that were either not available or suitable during the initial modeling phase.

Slide 14

Conceptual Massing Environment became the best solution given the time restraints and scope of work required to facilitate assessment report. A new linked dome model was created by stripping down and removing the original curtain grid system and massing model host from each dome pentagonal segment back down to its beings as a planar surface and then geometry exported. The structural CME modeling approach mimicked the drawing approach of the original hand drafted documents, replicating the triangular grid system and using the geometric information originally calculated, compiled and documented.

Slide 15

The planar surface segment imported into CME and reference points placed on the intersections of the planes to host nodes needed to create the dome segment geometry. Reference lines then created along the edges of the planar surfaces, snapping to the hosted reference points creating the reference geometry need to host the structural elements. Reference points hosted to midpoints of the reference lines to host the structural members. Structural members created using 2d model lines to create structural shapes hosted to reference points then re-hosted to the reference points on the reference lines between the reference nodes. Forms were then extruded along the reference lines from the 3D structural shapes. The accuracy of the reference line lengths, dihedral angles and geometry matched the original drawings and calculated values within a margin of error +/- 5mm

Slide 16

This was completed for each structural shape along the appropriate reference line and plane, except along the leading edge where each segment joins to the adjacent segment Process applied to both dome inner and outer segments then imported into the Revit model and polar arrayed as 5 segments to create the entire 360 degree dome. Once imported back into the upgraded model, existing and addition model views provided the roadmap for visually inspecting and documenting each structural member of the inner support dome and assessing the condition of each of the node connection point to the outer trussed dome frame. Completed condition assessment information obtained from visual data and onsite review entered back into to the upgraded Revit Structure model to complete documentation required to augment the written report

Slide 17

Revit Structure model and associated building information data proved to be invaluable in facilitating the design and construction of a very complex existing structure, providing an unprecedented understanding of the entire facility and related structure. Access to a completely digitized 3d model that accurately conveys the as-built condition, including expansions, upgrades and current conditions of the existing facility. The model can be utilized for any future upgrades, additions or repurposing of the existing facility should any new design opportunities be proposed or presented. The updated dome structural model to be considered for utilizing dynamo to populate structural framing elements as well as testing for export to an analysis program.