The effect of which loads decreases as the height of cover over the culvert increases?

The effect of which loads decreases as the height of cover over the culvert increases?

• A. Wind Loads
• B. Dead Loads
• C. Live Loads
• D. Environmental Loads

Answer: (C)

When a culvert is buried under soil, the surrounding backfill can carry part of the applied load through arching and friction in the soil. As the height of cover increases, more of the traffic-induced load is shared by the surrounding soil rather than transmitted to the culvert itself. That means the culvert’s response to live loads (vehicle loads) decreases with greater cover, since the soil is taking more of the load. In contrast, dead loads increase with more cover because you’re adding more soil weight and backfill on top of the culvert. Wind and other environmental loads aren’t tied to how deep the culvert is buried in the same way, so they don’t show the same reduction with increased cover. So the load type whose effect decreases as cover height increases is live loads.

When a culvert is buried under soil, the surrounding backfill can carry part of the applied load through arching and friction in the soil. As the height of cover increases, more of the traffic-induced load is shared by the surrounding soil rather than transmitted to the culvert itself. That means the culvert’s response to live loads (vehicle loads) decreases with greater cover, since the soil is taking more of the load.

In contrast, dead loads increase with more cover because you’re adding more soil weight and backfill on top of the culvert. Wind and other environmental loads aren’t tied to how deep the culvert is buried in the same way, so they don’t show the same reduction with increased cover. So the load type whose effect decreases as cover height increases is live loads.