2008 GT STRUDL Users Group Meeting & Training Seminar

1. 2008 GT STRUDL Users Group Meeting & Training Seminar Soil-Structure Interaction Analysis of a Composite Structure on a Backfill HilltopWSRC-STI-2008-00269 Rev 0Lisa Anderson, Bechtel National, Inc.Jay Amin, Washington Savannah River Co.June 25, 2008

2. Overview • Scope of Analysis • Building Description • Analysis • Conclusions

3. Scope of Analysis

4. Scope of Analysis • Assess feasibility of adding new process to this complex • Building complex constructed in 1980’s • Not designed to resist current seismic loads or wind loads • Lateral load path is not well defined

5. Scope of Analysis • Evaluate the structures for • Normal operating dead and live loads • PC-3 seismic loads* • PC-2 wind loads* • administrative controls will stop process prior to tornado events • II/I concerns* *DOE Standard 1020

6. Building Description

7. Building Complex • Split up for analysis • Filter Cells and Hold Tank Room (Concrete) • Enclosure Building (Steel) • Benzene Stripper Building (Composite)

8. Building Complex

9. Building Complex

10. Analysis

11. Finite Element Models • Create finite element models in GT STRUDL using a model builder program • Filter Cells and Hold Tank Room • Convert Filter Cells and Hold Tank Room to SASSI House Model • STRUSASSI • Enclosure Building • Benzene Stripper Building

12. Filter Cells and Hold Tank Room SBHQ6 Elements Filter Cells 1:1 Mesh except column support Hold Tank Room

13. Enclosure Building

14. Benzene Stripper Building SBHQ6 Concrete Elements < 2:1 Mesh

15. General Site Analysis • Generation of time histories • Amplified for hilltop • Free-field soil analysis

16. Amplified Hilltop Response Spectra

17. Horizontal Hilltop Time History Time History Plot

18. Soil Profile

19. Soil Profile

20. Free-Field Soil Analysis Best Estimate Soil (Upper and Lower Bound not shown) High Strain Low Strain

21. Filter Cells and Hold Tank Room Analysis • Perform Soil-Structure Interaction (SSI) on the Filter Cells and Hold Tank Room SASSI model • Obtain response at connection points of Enclosure Building • Apply response to FEM of Enclosure Building and Benzene Stripper Building

22. Filter Cells and Hold Tank Room Mode Shapes EW Frequency 26 Hz NS Frequency 28 Hz E-W N-S

23. Filter Cells and Hold Tank RoomTransfer Functions Fixed-Base Soil Structure Interaction Frequency 26 Hz Frequency 7 Hz

24. In-Structure Response Spectra at Top of Filter Cells

25. In-Structure Response Spectra at Top of Hold Tank Room Spectra Amplifies at Thin Wall of Hold Tank Room

26. Filter Cells and Hold Tank Room Analysis • Perform SSI on the House model • Obtain zero-period accelerations at each node • Apply as equivalent static loads in GT STRUDL • Run GT STRUDL stiffness analysis • Apply section cuts to obtain demands • Compute capacities based on existing conditions • Shear wall demand to capacity spreadsheet macro • Report demand to capacity ratios

27. Filter Cells and Hold Tank Room Shear Demands

28. Enclosure Building Analysis • Run GT STRUDL response spectra analysis • Using the soil-structure interaction input motion • Check ASD9 code • Check ASCE 7-05 wind loads • Report demand to capacity ratios

29. Enclosure Building Mode Shapes EW Frequency 2.9 Hz NS Frequency 4.3 Hz N-S

30. Enclosure Building Mode Shapes at Stairwell Occurs at NS Frequency 1.8 Hz

31. Enclosure Building ASD9 Code Check Members in red fail due to seismic F factor is necessary

32. Enclosure Building F Factor The elastically calculated PC-3 seismic responses can be reduced by the inelastic energy absorption capacity factor (Fμ).

33. Enclosure Building ASCE 7 Wind Loading 107 mph

34. Enclosure Building Wind Demand to Capacity Ratios

35. Enclosure BuildingShear Comparison PC-2 Wind Base Shear EW 137 kips < PC-3 Seismic Base Shear 150 kips PC-2 Wind Base Shear NS 68 kips < PC-3 Seismic Base Shear 112 kips

36. Benzene Stripper Building Analysis • Run GT STRUDL response spectra analysis • Using the soil-structure interaction input motion • Including ASCE 7-05 wind • Check ASD9 code • Report demand to capacity ratios • Apply section cuts to obtain concrete demands • Compute capacities based on existing conditions • Shear wall demand to capacity spreadsheet macro • Report demand to capacity ratios

37. Benzene Stripper Building Mode Shapes EW Frequency 3.9 Hz NS Frequency 3.0 Hz

38. Benzene Stripper Building Seismic Demand to Capacity Ratios

39. Benzene Stripper Building ASCE 7 Wind Loading 107 mph

40. Benzene Stripper Building ASCE 7 Wind Loading

41. Benzene Stripper Building Wind Demand to Capacity Ratios Braces that exceed 1.0 are qualified as tension members

42. Seismic Displacements Enclosure Building Displacement Wind Seismic NS 0.07 in 0.26 in EW 0.18 in 0.97 in Vertical 0.98 in 1.21 in Stripper Building Displacement Wind Seismic 0.001 in 0.001 in Enclosure North

43. Conclusions

44. Conclusions • Adequate for PC-3 seismic and PC-2 wind loads • Enclosure Building • Filter Cells and Hold Tank Room • Benzene Stripper Building • No pounding occurs

45. Questions?