At that level, do we absorb?
As far as shielding, if radiation occurs within the shielding, then it seems obvious that spaced shielding would work better than just more thickness, where you have an open buffer zone before reaching the inner shielding.
Yes, we absorb energy from these hot nuclei. We are thick slabs of water that can slow a cosmic ray, and that means it deposits energy in us. If you look at the chart from the transport calculator, you see the flux is not high, but it is constant. Also the transport calculator does not include secondaries like mesons and neutrons or brems photons that come from the shielding itself. You need to use a code like MCNP for that, and that's not free on the web. So the transport calculator does not do doses, just attenuation of the incident without considering secondaries or absorption in people.
Why put a space? The particle will just cross that space.
Shielding is done in layers, though. Typically a plastic layer for real light stuff and to slow neutrons, an aluminum shield to stop light particles, then a denser shield to stop more particles and the bremstrahlung radiation, then sometimes a plastic type again for neutrons. It cuts weight; the low-Z materials stop the light particles OK. For electronics there are very small very dense shields (like the tantalum Rad_Pak) that are small. You could not make a personnel shield.
On the lighter side, a few years ago National Geographic had a shot of NASA's Janet Barth, from the "Living With A Star" program, wearing corrugated plastic sleeves filled with water for a wearable shield. Actually it was a bunch of gadjets for making tubular ice in your freezer stapled together but it sure looked cool.
If we had wanted to, we could have launched the Shuttle with the main tank attached and leave it up there, so that now we'd have a bunch of big empty cylinders in orbit. Tie them together and fill them with water and you have a big habitat and shield. It would help to find water on the Moon, but if we wanted to we could boost a couple tons a year, if we had a good ongoing space program.