Where the bridging crew??
am I the only one who is surprised by the thin layer of the road?
the actual paved surface (asphalt or concrete) is often just 10–30 cm thick. What really matters is what's beneath it:
Road Structure (Typical Layers)
1. Surface Layer (Pavement)
– Asphalt or concrete (about 10–30 cm)
– Smooth finish for vehicles, but not structurally strong by itself
2. Base Course
– Crushed rock or gravel (20–40 cm or more)
– Distributes load and provides drainage
3. Sub-base
– Lower-quality materials (sand, recycled concrete, etc.)
– Further support and helps prevent settlement
4. Subgrade (Natural Soil)
– The native ground — its stability is crucial
– If this layer is weak (due to water erosion, poor compaction, or soil type), it’s a recipe for sinkholes or road collapse
So if water seeps into the subgrade (via cracked pavement or broken pipes), it erodes the soil or creates voids. And since the road layer above is relatively thin, it collapses eas
ily once support below is gone.