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Quenneville and Mohammad used the cluster concept to arrive at the
splitting capacity of bolted connections. For interior connections, they assumed
that a group of bolts in a connection can be assumed as one cluster
if the distance between the rows of bolts does not exceed the depth of the
member less the unloaded edge distance (h-ep). The assumed angle of distribution
is therefore 63°. On the other hand, if the distance between the
rows of bolts exceeds the depth of the member less the unloaded edge distance
(h-ep), the resistance of each row is determined and the connection
resistance would constitute the sum of the resistance of each of the rows.
Load distribution in interior joints.
35-7-7 A J M Leitjen
Splitting strength of beams loaded by connections, model comparison
See 4.3 Dowel-type fasteners loaded perpendicular to grain
35-7-2 K Komatsu, S Takino, N Nakatani, H Tateishi
Analysis on multiple lag screwed timber joints with timber side members
Abstract
Non-linear load-slip relationships of multiple lag screwed timber joints
with timber side members were analyzed by making use of the classical
Lantos theory which deal with load distribution in the members of general
multiple timber joints under axial force.
Load-slip relationships obtained from single lag screwed joints were fitted
by the three parameters exponential function. Then step-wise load incremental
calculation method was applied on a series of the finite deferent
equations which were obtained by applying Lantos theory to the multiple
lag screwed timber joints under axial force.
A series of experimental studies was also conducted on the double sided
timber to timber joints fastened by single raw lag screws. We prepared
basically five different combinations of test specimens composed of single
main member and double sided members connected by several lag screws
located along one line.
From the comparisons between calculations and experimental result, it
was recognized that the non-linear calculations could predict the nonlinear
load-slip behaviour at least up to the yielding point of each multiple
lag screwed joint. So far as using the 'load incremental method', it was difficult
to predict precisely on the ultimate stage of each multiple joint specimens.
Maximum strength per fastener tends to decrease as the number of fastener
increases, and also this trend could be predicted theoretically.
Conclusions
In this article, we tried to apply the classical Lantos theory to the nonlinear
analysis of the multiple lag screwed timber to timber joints. From the
comparisons between calculations and experimental results, it was recognized
that the theoretical calculations could predict precisely the nonlinear
load-slip behaviours up to the point, which exceeded the yielding point,
but before maximum load of each multiple lag screwed joint specimen.
So-called multiple effect on the maximum strength per fastener was also
recognized by experiment as well as theoretical calculation.
So far as using the 'load incremental method', it was difficult to predict
precisely beyond the stage of ultimate load where local cracking or splitting
had already occurred.
CIB-W18 Timber Structures – A review of meeting 1-43 4 CONNECTIONS page 4.64