Copyright © 2017 Pinnacle Infotech, Inc.

Global Leader in BIM Serviceswww.pinnaclecad.com

innacle is responsible for creating the 3D BIM Models of PAcademic Core Buildings 1, 2 and 3 of Ohlone College, (comprising of 5 floors of Building 1, 6 Floors of Building 2

and 6 Floors of Building 3) that would rise from the center of the Ohlone College campus on Mission Boulevard in Fremont. The purpose of construction is accomodating 150 people, including college faculty, students, elected officials and other community members for attending Ohlone’s Academic Core Project. The three structures totaling 188,000 square feet will house classrooms, laboratories, offices, conference rooms and a library, Each building will focus on particular academic discipline.

Scope of WorkOur scope of work for the project included preparation of Concrete 3D Model & Update, Shop Drawing Creation and Constructability Review for the 3 Buildings.

Trades Covered: Concrete Structure

Software Used: Revit 2016

Challenges & Solutions

RFI Snap - Issue identified

ACADEMIC CORE BUILDINGS 1,2,&3-OHLONE COLLEGE

Fremont, California, USA

[Educational]

BIM Start Date October, 2016

Project Area 395,638 Sq ft

Architect

8 Engineers

Cannon Design

Team Size

Balfour Beatty ConstructionGeneral Contractor

BIM End Date March, 2017

Robert A. Bothman ConstructionConcrete Contractor*

Ohlone Community College District Owner/Developer

LOD: 400

We faced lots of design issues in the input documents. Few dimensions were mismatched between Architectural & Structural input documents. For example, we could not found the size of the sump pits as well as the position from the nearest grid reference marked in the PDF pertaining to the Structural drawings.

Solution: We raised RFIs for the issues and considered logical assumptions for the same. While sending the concrete lift drawings we marked portions in cloud for each pending RFI. For example, we considered 2'-0"x2'-0" sump, located 1'-8" below grid 1-D.5 & 4'-3" left from grid 1-2.5 and top elevation of Sump Pit as 421'-6" and took client suggestion through weekly Webex meeting.

We received the final Rebar shop drawings from client more than 2-3 times to revise our concrete lift drawings. However we found some discrepancy between Rebar drawings and original contract documents.

Solution: We coordinated with client via e-mail and phone and raised RFCs (Request for clarifications) to resolve the concern.

We did not get 3D model of other trades in Revit to coordinate with the concrete model. Moreover, we could not found the exact depth and width of the stepped footings with reference to the Structural Contract drawing and Wall Elevations.

Solution: We used 2D drawings as well as the CAD 3D model of other trades for coordination.We also measured the dimension from the input PDF and shared snapshot of the model for the stepped footings to seek client approval.

Challenge 1: Design Issues//Missing Input

Challenge 2: Frequent Drawing Revisions

Challenge 3: Input Challenge

Pinnacle’s Value AdditionWe raised 47 RFIs and 10+ RFCs for various constructability and coordination issues and communicated with client , GC and other subcontractors through Newforma and Goto meeting to resolve the same. Based on our RFIs and RFCs design issues were resolved and input drawings were revised. RFIs were raised pertaining to: i. We have not found the top elevations of the wall foundations with reference to the Structural contract document " Site wall plan _S3.40" & Architectural contract document "Enlarged site plan_A-0012" and considered the top of footing as 422'-8", 423'-8" and 425'-2". ii. Moreover, with respect to structural contract documents "S3.04; PIER CAP DETAILS - BUILDINGS 2&3" & "S2032.A; FLOOR FRAMING PLAN - BUILDING 3 - LEVEL 2 - SECTOR A" we have found a column blockout at base of steel columns. We created the column cut-outs in slabs and placed embed (base plates). iii. In addition, with reference to the Structural contract documents " FLOOR FRAMING PLAN-BUILDING 1-LEVEL 2-SECTOR B_S2012.B, GRADE BEAM/ WALL FOOTING SCHEDULES AND DETAILS_S3.07 & GRADE BEAM ELEVATIONS_S3.08" we have found a few issues regarding the marked grade beams. According to the floor plan, the marked beams (GB-1 & GB-2C) are tagged as SLOPED and the SOG is flat and we have not found any slope indication on SOG. However the detail of beams (1/S3.07, 2/S3.07 & 3/S3.07) indicated that the top elevations of those beams are same with top of SOG elevation and the beam schedule mentioned the beam depth as 2'-6" and 3'-4" We requested client to provide us the exact information of slope of beams. iv. With reference to the Architectural contract document "EDGE OF SLAB PLAN - BUILDING 3 - LEVEL 3 - SECTOR B_AS133.B and Structural contract document FLOOR FRAMING PLAN - BUILDING 3 - LEVEL 3 - SECTOR B_S2033.B and WALL SECTIONS - BUILDING 3_S3.30", we have found a slab layout discrepancy in between the Edge of Slab plan drawing (AS133.B) and Structural section (1/S3.30). The edge of slab plan showed the slab edge dimension from grid 3-L as 1’-8” but the section drawing indicated the wall to extend upto top of slab elevation and the slab to be terminated at edge of walls. We followed the Edge of slab drawing and kept the wall below the slab.

Apart from Pinnacle RFIs, we received lots of RFI responses from other sub-contractors.

Solution: We prepared a RFI log for sub-contractors' RFIs and defined the trade to incorporate the same into concrete models.

Challenge 4: RFIs from Sub-Contractors