minimum number of bolts

huangyhg

minimum number of bolts
many design codes and specifications (e.g. aashto & aisc) require that bolted connections for structurally significant components contain a minimum of two bolts, regardless of the strength required.

today i was working with the nds timber design spec and noticed that this requirement doesn't seem to be included. did i miss it, or is one connector all that is required for bolted/lagged timber connections?
thanks!
find a job or post a job opening
i recently became involved in the 2005 nds code and i did not find a minimum number of bolts required.  note that there are 4 modes of connection failure (appendix i).  i programmed them all so i could duplicate their connection load tables (table 11g in particular) and then make adjustments for our specific details.  i never knew there was so much to wood design!!  i prefer redundancy in my connections because 28 years of experience has shown me that the connections are where the failures tend to occur and are the details most overlooked by designers.
i like the two bolt minimum regardless of material.
poke one hole on a piece of paper with a pencil and spin the paper.
try the same with two pencil holes.
i always liked this analogy with bolts.
sometimes you want the paper to spin, for example, to have a true pinned connection.
i am not an authority on wood design.
i can see situations that could arise where one bolt has way more capacity than the connection requires.  off the cuff (re  
i do a lot of wood design and the best advice i have ever recieved, was to provided resistance for the known forces.  what the engineer mean't who gave me this advice, was that you shouldn't add fasteners or increase   
here is a link to a master's thesis on "experimental investigation of group action factor for bolted wood connections" (free .pdf download)
i use two bolts to eliminate single point failure mode regardless of how small the load is.
regards,
lutfi
i would never use just one bolt for a gravity load-carrying connection, but for a beam seat on masonry, for example, where the bolt only provides a "lateral tie", such as the simpson glb beam seat, one bolt would be feasible.