Experimental and numerical investigations of the effect of buried box culverts on earthquake excitation

• Centrifuge tests to study soil culvert interaction considering three earthquakes.
• Kinematic soil culvert interaction reduces the input motion at surface.
• Quantify the effect of soil-culvert rigidity and soil density on input motion.
• Investigate the rocking of box culverts and surface foundation.
• Lateral movement of surface foundation due to ground shaking.

The seismic response of soils consisting of uniform sandy soils with two different relative densities Dr (50% and 90%) was investigated using the RPI geotechnical centrifuge facility, with a one-dimensional earthquake simulator at 60 g. The seismic soil structure interaction between the sand, buried box culvert, and surface foundations was also studied. The models were subjected to three earthquakes with different amplitudes and frequencies. Model settlements were recorded from 1 g to 60 g and during the seismic shakings; the ground response parameters were assessed. Rocking of structures was observed to be small for the box culverts compared to the surface foundation due to the soil confinement. The effect of kinematic soil structure interaction between the dry sand, box culverts and foundations was also explored. Kinematic soil culvert interaction was found to lead to a large reduction in the peak ground acceleration at the soil surface, which can reach up to 50%. Further numerical modeling was performed to investigate the effect of soil cover height on the kinematic soil culvert interaction and these results are also discussed in the paper.