Future Infrastructure Forum

Transcription

1 Future Infrastructure Forum Ian Moore, PhD, PEng Professor and Canada Research Chair GeoEngineering Centre at Queen s-rmc

2 1. Large scale computations Continuing to use advancing capabilities to study problems in new ways improve remaining approximations Bridge-foundation-water interactions (e.g. during seismic events) Wind-structure interactions Simulating construction and its effects

3 1. Large scale computations Example - understand culvert strength limit states & influence of 3D effects Testing (Lougheed) and Analysis (Elshimi)

4 Ultimate Limit State Tests Two ultimate limit states Standard load pad 600 x 250 mm CHBDC (AASHTO) wheel : 800 kn Bearing failure of soil 950 x 390 mm : 1100 kn Plastic moment capacity 1000 )Nk( ecrof 2.5 times larger pad CHBDC: 597 kn required 200 / resistance factor = 630kN 0 0 = 1100kN / Displacement (mm) 250

5 Three dimensional behaviour: analysis and design Tamer Elshimi (PhD, 2011)

6 ABAQUS analysis Geometry ¼ 0.45 m 2.4 m z y x 5m

7 Loads and deformations Z=600mm

8 Yielded zones

9 780 kn Yielded zones First yield

10 Yielded zones

11 Yielded zones

12 Yielded zones

13 Yielded zones Max. Load

14 Yielded zones End of test

15 Orthotropic shell performance Yielded zone Yielded zone Top surface (represents crests only)

16 Load choice for parametric study t n e m o m d a o l e v il m u m i x a M 70 CHBDC 60 AASHTO 50 ) m / 40 m. N30 k ( Total force (kn) P1 = Multiple presence factor (MPF) x Nominal load P2 = Dynamic load factor (DLF) x P1 P3 = Live load factor ( L) x P2

17 2. Infrastructure deterioration > 80% of Civil Eng. construction repair or replacement; need to determine: how much deterioration is too much? including deteriorated soil (erosion) Metal culvert, Hwy 401, ON

18 Invert corrosion original design thickness 90o Invert 135o Invert 180o Invert 90o Invert 135o Invert 180o Invert 90o Invert 135o Invert 180o Invert 90o Invert 135o Invert 180o Invert 90o Invert 135o Invert 180o Invert FOSY Corroded / FOSY Intact Corrosion H=3.0m Corrosion H=3.0m Corrosion H=3.0m Corrosion H=3.0m Corrosion H=3.0m Corrosion H=3.0m Corrosion H=3.0m Corrosion H=3.0m Corrosion H=3.0m Corrosion H=1.5m Corrosion H=1.5m Corrosion H=1.5m Corrosion H=10m Corrosion H=10m Corrosion H=10m D=2m D=2m D=2m D=4m D=4m D=4m D=6m D=6m D=6m D=4m D=4m D=4m D=4m D=4m D=4m Thickness reduced by corrosion Finite element analysis to determine resistance to failure by wall crushing % t left 25 0

19 Global buckling strength Reductions in stability are slow until significant wall loss has occurred (corrosion across angle of 135o) 100% 42% 12.5%

20 Non-uniform versus uniform corrosion Non-uniform - 25% remaining at the crest and valley, intact elsewhere (62% of the area remains). 25% 100% Non-uniform 25% Uniform : 75% 50% = 180o Angle from crown (degrees) 25%

21 Local buckling 3 complete wavelengths Solution for 3 mm plate Local rather than global buckling governs when wall thickness is less than 4 mm.

22 Influence of backfill erosion

23 3. Infrastructure rehabilitation Sewer replacement, Ottawa Y Surface Deformation Adjacent Pipeline Burst Head Host Pipe Culvert lining, East ON Replacement Pipe X

24 4. Poor/sensitive soil environments EXIT PIT ENTRY River Rig Drill Rod Reamer 300 Swivel Pipe product

25 Mud-loss during directional drilling

26 5. Construction and service life Simulate pipe installation by directional drilling; then determine how axial forces change over the life of the pipeline

27 6. Improved service lives For example, buried pipe research focuses on barrel performance, while many failures occur at joints; new work has developed rational design methods for joints

28 7. Performance-based codes Stormwater detention chambers Arches, crates, pipes,... HDPE, PVC, PP, Steel,... CSA B182 Standards AASHTO truck 1. short term load factor one month load factor long term earth loads Define load requirements Structural testing required Define tested product Test all variations? Needs sophisticated users (not a single product) How to monitor quality?

29 Research Themes Large scale computations Infrastructure deterioration Infrastructure rehabilitation Poor/sensitive soil environments Construction effect on service life Improved service lives Performance-based codes

30 Future Infrastructure Forum Ian Moore, PhD, PEng Professor and Canada Research Chair GeoEngineering Centre at Queen s-rmc