A theoretical question

[KOKONIS36]

What is the difference between "Standard Specifications" and "Guide Specifications" ? For example why the AASHTO "Guide Specifications for Design of Pedestrian Bridges" are not called "Standard Specifications for Design of Pedestrian Bridges" ?

 

[Qshake]

Probably something to do with not being fully accepted into the AASHTO family of design specifications.

Once a committee is convened and much research is crowded into a specification it goes to the engineering community for trial. After several years of use and more research the publication usually finalized.

This is not the only document that AASHTO has for guides. AASHTO also has a guide spec on seismic isolation and curved girder bridges.