Design Project 1 Replacement of Vehicle Bridge over

Design Project #1 Replacement of Vehicle Bridge over Spring Creek Centre County, PA Introduction to Engineering Design EDSGN 100 Section 002 3: 1 Designs Team 7 Melinda Mckeehan Josh Tumelty Megan Vareha Sophia Zitkus Presented to: Prof. Berezniak Spring 2018

Statement of the Problem ● A bridge located along Puddintown Road in Centre County, PA has recently been destroyed by a 100 -year flood event. ● Once damages had afflicted the site, important traffic flow to the local Mount Nittany Medical Center, nearby schools, and commercial areas had been rerouted to avoid this critical area in College Township.

Project Objective ● Penn. DOT Engineering District 2 -0 has issued the need for an emergency bridge design project to replace the destroyed bridge across Spring Creek.

Required Design Criteria ● Penn. DOT has set strict requirements for the replacement bridge. ● These specifications include: ○ standard abutments ○ no piers ○ medium strength concrete for deck material (0. 23 meters thick) ○ no cable anchorages ○ a design for a load of two-225 k. N trucks with one in each traffic lane ○ deck elevation must be 20 meters high ○ deck span of 40 meters wide ● Both Warren and Howe bridge designs must be prototyped. ● Determined individually: member type, cross section type, size

The Technical Approach Phase 1: Economic Efficiency ● Economic efficiency was determined through the use of Engineering Encounters Bridge Design 2016 (EEBD 2016) software. ○ All specifications provided by Penn. DOT were accounted for in the analysis. ● Bridge costs within $150, 000 and $250, 000 for each bridge type. ● Each design ensured the safe support of both the dead load and live load.

The Technical Approach Phase 2: Structural Efficiency ● Two prototype bridges were designed and constructed ● Materials: ○ Sticks (4 -½ x ⅜ x 1/12 inch) ■ wooden (white birch) ■ Popsicle (craft) sticks ○ Elmer’s white glue ○ Hot glue (only for connecting eight struts and floor beams between the two adjacent truss sections) ● No more than 60 Popsicle sticks each ● Penn. DOT’s parameters: ○ 13. 5” length ○ 4” height ○ 4. 5” width. ● Load tested to catastrophic failure

The Results Phase 1: Economic Efficiency ● Howe Total Cost: $214, 961. 27 ○ solid bars: bridge strength ○ hollow tubes: financial favorability ○ minimized number of products ● Warren Total Cost: $207, 512. 93 ○ quenched & tempered steel: smaller members ○ hollow tubes: financial favorability

The Results Phase 2: Structural Efficiency ● Howe: ○ structural efficiency: 423. 07 ○ average efficiency: 295. 00 ○ load failure: 66. 0 lbs ○ forensic: shearing force destabilized struts and floor beams ● Warren: ○ structural efficiency: 379. 31 ○ average efficiency: 328. 74 ○ load failure: 66. 0 lbs ○ forensic: single joint

The Best Solution ● Howe Bridge ● Economic Efficiency ○ Warren: $7448. 34 less ● Structural Efficiency ○ usually: Warren more efficient ○ maximum: Howe holds maximum ● Design Efficiency ○ Warren: 547. 08 $/SE ○ Howe: 508. 18 $/SE ● Constructability ○ Production Costs: ■ Warren: $130, 112. 92 ■ Howe: $137, 561. 27

Our Conclusions Penn. DOT asked that a new bridge over Spring Creek be quickly designed in order to reopen the roadway leading to the Mount Nittany Medical Center. The completion of a functional bridge is vital to shortening the travel time to the center and will permit the citizens of the surrounding community to reach the center faster during an emergency. The bridges that was designed met all of the design criteria including: the price range, the absence of a pier, the utilization of medium strength concrete, and having standard abutments. After reviewing the designs from both Bridge Designer 2016 and the load testing results from each of the prototype bridges, it is recommended that the replacement bridge across Spring Creek be a Howe Truss Bridge. The Howe Bridge design, while costing $7, 448. 34 more than the Warren Bridge, is more structurally efficient. The Howe design also has a lower cost per structural efficiency value at $508. 18/SE versus the Warren’s at $547. 08/SE.

Our Recommendations Next Steps 1) Survey the Site 2) Address design flaws of preliminary design 3) Contact 3: 1 Designs about additional pricing Areas Needing Further Investigation 1) The Lateral Bracing between the Trusses 2) Project Site

In Closing 3: 1 Designs would like to express our sincere gratitude to Penn. DOT for providing us with a unique design project that allowed us to bond as a design team and travel further down our paths as aspiring engineers.