1. Dept. of Civil Engineering
Mapping NYC
Below Ground Level
George Deodatis
Dept. of Civil Engineering
Columbia University

2. Plus: transportation tunnels, foundations of buildings, etc.

10. Kaohsiung, Taiwan underground gas explosions.

11. There is soil in between the various utilities, tunnels, foundations, etc.

13. Soil is not uniform!

14. Soil heterogeneity in depth.

15. Soil heterogeneity in depth.

16. Soil Heterogeneity in 2D.

17. Soil Heterogeneity in 2D.

18. Soil heterogeneity is of course a 3D phenomenon.
Underground water further complicates the situation.

19. Detailed description of soil properties and of their inherent heterogeneity in 3D is absolutely critical for the behavior of buried utilities, tunnels and foundations, both under normal and under extreme conditions.

20. The number of available geotechnical borings in New York City, although large, cannot cover every location. There are gaps without any borings.
Sophisticated techniques have been developed to infer soil properties in between geotechnical borings (accounting for uncertainties).

21. Thank you!