Generally speaking, I routinely use:
- IBC & California Bldg Code (I do work in a several different states. I think you can get both of these electronically, but I know
the IBC is available as PDF.)
- ASCE 7 (available as a PDF)
- AISC steel manual and seismic manual (I'm a hardcopy guy, but I believe they're now available electronically)
- AISC design guides (available free to AISC members in PDF)
- ACI 318 (which you can get in PDF)
- NDS/SDPWS (also available in PDF)
- various APA references (most available in PDF)
- AISI cold-formed steel design standards (CFSEI members can get all (almost all?) of them for free as PDFs.)
Although I could probably live without them, I'd be sad not to have my collection of the various Blodgett books. I used to think I was too lazy to digitize them, but maybe my motivation just shifted.
On the B-list, I'd probably include:
- Galambos' Guide to Stability Design Criteria for Metal Structures (I don't use it all the time, but when I need it....)
- Roark's handbook (same reason)
- Terry Malone's Analysis of Irregular Shaped Diaphragms (because architects think that a straight line at the diaphragm boundary is some kind of sin....)
- PCA notes on 318 (although with 318-14 I've found the ACI design manuals pretty handy as a substitute)
- pick your favorite geotechnical reference (e.g. DM7.0x) if you do enough geotech/retaining walls/subterranean levels to justify it
- ACI 562 if you do enough concrete retrofit to justify it
Hrm...maybe I'm not a good character reference for a minimal library....
I also periodically refer to the Van Nostrand-Reinhold engineering series (e.g. Timoshenko's elastic stability, etc) when I get something hinky to analyze.