Presentation Outline. Need for Creative Solutions in Technical Construction Problems. creativity, imagination, and innovative skills.

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1 Construction Engineering Process and Knowledge Requirements for Fostering Creative Design Solutions on Infrastructure Projects Robert B. Bittner, Bittner-Shen Consulting Engineers Robert L. Schmitt, University of Wisconsin, Platteville Presentation Outline Need for Creative Solutions Process for Attaining Optimal Solutions Case Histories Knowledge, Skill, & Experience Requirements Conclusions Need for Creative Solutions in Technical Construction Problems Young engineers seek a challenge and to use their creativity, imagination, and innovative skills.

2 Every construction project has unique technical challenges. Few major projects can be considered routine, each must be uniquely engineered. Need for Creative Solutions in Technical Construction Problems Technical Solutions must work and be efficient and cost competitive. Process and Sequence for Attaining Optimal Construction Solutions Team effort requiring construction personnel with a wide range of talent and experience. Beneficial for individuals with a wide range of experience to participate. 10-step process Developed from successful project execution on multiple projects by Ben C. Gerwick, Inc. & Bittner-Shen Consulting Engineers, Inc.

3 10-step process 1. Identify key technical problems 2. Collect and review relevant information 3. Defining i the problem clearly l 4. Identify available feasible solutions that have worked successfully in the past 5. Conceive or create new solutions 10-step process 6. Confirm the viability of the new solutions 7. Evaluate the solution options 8. Select the optimum solutions 9. Detailed design and confirmation testing 10. Implement and monitor Case Histories Bridge Foundations for the New Tacoma Narrows Bridge, Washington Launching the Oresund Immersed Tube Tunnel Connecting Denmark and Sweden Braddock Dam on the Monongahela River, Pennsylvania Piers for the Bath-Woolwich Bridge, Maine

4 Bridge Foundations for the New Tacoma Narrows Bridge, Washington Source: skyscrapercity.com Bridge Foundations for the New Tacoma Narrows Bridge, Washington 160-ft water depth Rapid 7-knot tidal currents 4-month period Two main pier caissons required 64 anchors with a safe working capacity of 500 tons each 10-Step Construction Engineering Process Step Action Taken Identify problem Build main span foundations Collect & review data Hydrologic studies, loads Define problem Deep water & fast current Identify solutions Dead weight & drag anchors Create solutions Driven plate anchor system Confirm solutions Test-driven plate anchors Evaluate options Significant cost differences Select solutions Anchors with 500-ton capacity Design & confirm Calculate working stresses Implement & monitor Measure anchor line tension

5 Launching of the Oresund Immersed Tube Tunnel Connecting Denmark and Sweden Source: roadtraffic-technology.com Oresund Immersed Tube Tunnel Match-casting 20 concrete tunnel elements - 55,000 tons each Oresund Immersed Tube Tunnel Casting a 22-m long tunnel segment on a fixed casting bed, then skidding forward to clear the bed for the next casting.

6 Oresund Immersed Tube Tunnel Skidding process repeated 8 times to complete a single 176-m long tunnel element. Challenge - how to skid a very rigid 55,000-tn tunnel element (28 hours after casting the prior segment) without cracking exterior. Oresund Immersed Tube Tunnel 6 pile-supported pp skid beams aligned under each of the 6 tunnel walls. 288 hydraulic jacks (300-tn capacity each) provided a 3-point support system. 6 hydraulic rams (600-tn capacity each) travelled on top of and reacted against the skid beams. 10-Step Construction Engineering Process Step Identify problem Collect & review data Define problem Identify solutions Create solutions Confirm solutions Evaluate options Select solutions Design and confirm Implement & monitor Action Taken Skid 55,000 ton segment in place Loads, tunnel dimensions Skid without cracking exterior Pile supports, hydraulic jacks Three-component system Calculations & model testing Significant assembly activity Skid beams react with jacks Calculate forces & stresses Measure loads during skidding

7 Braddock Dam on Monongahela River, PA Source: port.pittsburgh.pa.us Braddock Dam on Monongahela River, PA Float-in techniques rather than river diversion with circular cells and site dewatering. Final solution consisted of two precast dam shells (333-ft and 265-ft long, 125-ft wide and 40-ft high) constructed off site at a downstream dry dock location. Braddock Dam on Monongahela River, PA Two dam segments were launched and towed 22 miles upstream to the dam site for placement on the drilled shaft foundations. After landing and leveling the segments, were locked to the drilled shafts with tremie concrete.

8 10-Step Construction Engineering Process Step Identify problem Collect & review data Define problem Identify solutions Create solutions Confirm solutions Evaluate options Select solutions Design and confirm Implement & monitor Action Taken Construct using alternate means Cast-in-place or precast Avoid river diversion/dewatering Precast segments Fabricate off site and float in Confirm precast shell size Cost, schedule, & risk advantage Off-site fabrication Calculate installation stresses Verify in-place dimension Bridge Piers for Bath-Woolwich Bridge, ME Source: flatironcorp.com Bridge Piers for Bath-Woolwich Bridge, ME Concept based on precasting bridge pier shells on shore, while the drilled shafts were installed and cut-off under water.

9 Bridge Piers for Bath-Woolwich Bridge, ME Innovative float-in cofferdam system for 6 piers. Steel cofferdam was then attached to the top of the precast shells. Positioned over the top and lowered on to the drilled shafts. 10-Step Construction Engineering Process Step Identify problem Collect & review data Define problem Identify solutions Create solutions Confirm solutions Evaluate options Select solutions Design and confirm Implement & monitor Action Taken Float-in cofferdam for piers River depth, bridge dimensions Sequence pier assembly Precast bridge pier shells Float in shells and attach to shafts Dimension shaft connection Shell float-in is significant act. Position, level, lock connection Calculate lock connection Measuring during installation Key Knowledge, Skill, and Experience Requirements for Providing Creative Solutions to Technical Challenges of Construction

10 Knowledge, Skill, & Experience Requirements 10 to consider #1 An understanding of the forces of nature: Wind Current Hydrostatic Seismic Impact Friction Earth pressure Knowledge, Skill, & Experience Requirements #2 An ability to clearly see and define the problem #3 A sound basis in engineering fundamentals Knowledge, Skill, & Experience Requirements #4 A facility with analytical tools for structural analysis

11 Knowledge, Skill, & Experience Requirements #5 Ability to communicate ideas #6 Ability to work within a team and lead Knowledge, Skill, & Experience Requirements #7 An understanding of construction costs #8 An understanding of construction scheduling Knowledge, Skill, & Experience Requirements #9 An ability to identify, evaluate, and mitigate potential risks

12 Knowledge, Skill, & Experience Requirements #10 An ability to identify and evaluate potential environmental impacts Conclusions Construction engineering is an exciting field with a lifetime of challenges and creative endeavour opportunities. One of the most challenging activities within this discipline is creating and developing innovative optimized solutions for the many technical problems. Conclusions A 10-step procedure for creating and developing these optimum technical solutions leads to success. Four case studies illustrated the process steps. The team effort requires a wide ranging mix of skills, talent, knowledge and experience.

13 Conclusions This mix covers not only estimating, scheduling, cost control, and project planning, but structural and hydrodynamic analysis, risk evaluation, analysis, and mitigation, and an understanding of environmental impacts of construction and how to minimize them. Questions and Discussion