Please criticize my idea, thanks!
For making shipping containers easily reusable as structural components for modular buildings, and reducing their carbon footprint, we want to made their structure out of wood instead of steel.
Imagine mass producing wood shipping containers with building features (insulation, windows, plumbing and wires) in a manufacturing cluster city, all kinds of finished goods are packed inside these containers and shipped to a consumer market where the containers are stacked up to become permanent buildings.
According to wikipedia, Shipping containers should have a stacking strength to withstand a superimposed weight of 216,000 kg, allowing stacking a total of 7 layers, 36,000 kg maximum for each layer.
Pine is the most abundant and affordable wood in the US. According to matweb, pine has a compressive strength of 33 MPa along the grain.
If we use pine for the 4 corner posts in the 4 corners of a shipping container, the minimum cross section of all 4 corner posts combined is 216000*9.8/33e6 = 0.064m2.
Ideal load distribution: each corner post only need 0.016m2 (about the size of a common 6inx6in lumber).
worst case load distribution: all stress is concentrated on one corner. We need 4 lumbers sized 6inx6in for each corner.
Update: I found a very informational video on youtube: https://www.youtube.com/watch?v=hk6BQDPw924