just like a girl wearing a heavy clothes，her face turns red after wearing these heavy stuff，look！
But there still are some mesh structure on Bridges! see
in these cases, mesh is used as a handrails, or some structures protecting things falling down. this is one function
but there is the other function—filtrating lights
this bridge is called snake bridge, just like the madam from other side of GOTO MEETING said, mesh can used to reduce sunshine. we can reduce the sunshine by reducing the open area.
and there is the third function I am stilling working on it 🙂