Eriksson Culvert follows the seismic analysis procedure outlined in FHWA-NHI-10-034.
Below is an example calculation of this analysis, as well as the corresponding Eriksson Culvert file.
Design Parameters
Geometric Parameter | Value |
|---|---|
Clear span | 20 ft |
Clear Height | 11.66 ft |
Slab thicknesses | 14 in |
Wall thicknesses | 14 in |
Joint Location | 36 in up from center line |
Fill depth | 16 ft |
Haunch dimensions | 15 in depth and width |
Seismic Parameter | Value |
|---|---|
Soil density | 130 pcf |
Poisson’s ratio of soil | 0.5 |
Peak ground acceleration | 0.42 |
Ground shear modulus | 1460 ksf |
Slip interface | no slip |
Estimate the Free-Field Ground Strain and Relative Displacement
(Step 1 of FHWA-NHI-10-034, chapter 13.5.1)
The maximum free-field ground shear strain, 𝛾max, can be estimated by using the following equation,
where 𝜏max is the maximum earthquake induced shear stress,
For this example,
