1. Bethesda Triangle Brian Groark Construction Management Faculty Consultant: Dr. Messner

2. Bethesda Triangle 14 story apartment building Additional 4 stories below grade for parking 580,000 SF Cast in place concrete structure Offices and retail on plaza level High end apartments on floors 12- 14

3. Bethesda Triangle Owner: Bethesda Triangle, LLC CM: Encore Development Construction began on February 14, 2002 Phased occupancy Little site space

4. Bethesda Triangle

5. Thesis Overview SIPS Schedule Change emergency generator Change formwork Guidelines for mold prevention

6. CM Depth Short Interval Production Schedule (SIPS)

7. Reasons for Using SIPS Lack of solid schedule for the project Project will finish extremely late Needs solid, detailed schedule for all aspects of the project Repetitive floors work well for SIPS

8. SIPS Create a detailed SIPS schedule for the concrete structure Compare it to the original duration for the structure

9. SIPS Each floor is broken up into 4 sections Crews follow in progression through all the sections and floors Each section has the same duration

10. Section Layout

11. SIPS Floors G4 – plaza level are the same Floors 2 – 14 are the same Each section takes 2 weeks to complete

12. SIPS

13. Results Original duration was 44 weeks SIPS duration is 31 weeks Time saved is 13 weeks

14. Electrical Breadth Change Emergency Generator

15. Original Generator 2 mega-watt generator Power entire building in the event of a black out Sell extra power back to the grid at times when the costs of running the generator are less than electricity costs

16. New Generator 350 kilo-watt generator Power only emergency systems Emergency lighting and alarms Fire pump Stairwell pressurization Smoke exhaust Elevator

17. Initial Costs 2 mega-watt – $540,000 350 KW - $40,000

18. Cost Analysis

20. Costs of running the generator to power the building were compared to purchasing electricity on an hourly basis

21. Results No profit is shown from running the generator Price of diesel fuel has increased

22. Recommendation Use proposed generator Initial cost savings of approximately $500,000

23. Structural Breadth Change Formwork System

24. Original Formwork Traditional formwork Built in place with shoring Stripped and re-shored

25. New Formwork System Symons flying truss system Large aluminum forming tables are flown into position with a crane Much higher productivity

26. Slab Original slab was a flat slab with drop panels Flying truss system can only be used with flat plate slabs Slab was redesigned to a 10” flat plate to accommodate the new forming system

27. Productivity With a crew of six workers: Hand set system – 544 sq ft per day Flying truss system – 7500 sq ft per day

28. Comparison Form costs Slab Costs

29. Results Total cost savings of approximately $950,000

30. Research Mold Prevention Guidelines

31. Effects of Mold in Buildings Less serious symptoms of toxic mold poisoning Skin rashes Fatigue Coughing Headaches

32. Effects of Mold in Buildings More serious symptoms of toxic mold poisoning Impaired breathing Memory loss Hearing, speech, and eyesight degradation Loss of balance

33. Causes of Mold Moisture Leaks Condensation

34. Guidelines for Prevention 1. Clear details of all exterior penetrations 2. Design must provide for adequate roof drainage 3. No changes to design of enclosure without architects approval 4. Proper slope of grading

35. Guidelines for Prevention 5. Drywall must remain dry 6. Complete enclosure of building prior to drywall installation 7. Use drywall designed to reduce mold growth 8. Proper inspection 9. Proper operation of equipment

36. Conclusions SIPS can reduce schedule duration Larger generator is not profitable at current fuel prices Flying truss formwork greatly increases productivity Early mold prevention can save costly repairs in the future

37. Questions