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Important Note – These are descriptions to changes implemented in WoodWorks Connections for version 8.1 and may not reflect current program behaviour.
The program did not allow you to specify the factor for preservative-treated incised lumber for use in checks for tension design using net area and shear design for effective depth, independently of the fire retardant treatment factor for connection design. According to O86 table 5.4.3 and table 5.4.3, different factors apply for preservative and fire retardant for design criteria such as shear and tension, however according to 10.2.1.7 only the fire retardant factor applies to connection design. This has been rectified as follows
A checkbox has been added for preservative-treated incised lumber, and if checked applies the factor to effective shear capacity and tension capacity, net section. This checkbox is active only for those members that are stressed in axial tension or in lateral shear. The program checks that the least dimension of the member is less than or equal to 89 mm before applying the factor.
The existing unnamed input has been renamed Fire retardant factor. It applies to both connection design and to the tension net area and effective shear checks. For the shear and tension checks, it is compounded with a fire retardant factor that may also have been entered.
In previous versions of the program, the shear capacity using effective depth had no treatment factor applied to it. Now both the fire retardant factor and the preservative treatment factor are applied.
Where the program used to output just one treatment factor, referring to it as just “factor”. For those connections that require it, the output now reads, e.g.
Treatment Factor: Connection 0.8; Net tension 0.75.
Treatment Factor: Connection 0.8; Effective shear 0.75.
For most lapped shear connections, the calculations to determine maximum number of fasteners per row, and maximum rows, were no longer always correct with the following consequences:
Design would sometimes not allow fastener configurations that could be designed, and at other times design for a number of fasteners that cannot fit within the connection. These problems with incorrect design were most common with bolted connections, and have been corrected.
Even for those connections that were correctly designed, the program would position the fasteners incorrectly, sometimes to the point that they were drawn outside of the connection. Problems with incorrect positioning of fasteners in the drawing occurred with bolts, nails, and wood screws. The problems always occurred in an orthogonal connection when only the horizontal side member is loaded. When loads are on the main member or both members, the problems occurred more intermittently. The problems occurred in both the main and side member when there was a non-zero overhang or inset.
The problems occurred frequently in skewed connections, rarely in splice connections, and for ledger connections when the load is perpendicular to the connection. They have been corrected.
The following problems with the orthogonal lapped shear connection type were introduced with version 8 and corrected for 8.1:
For the orthogonal bolted connections, if the Bolts per Row is set as unknown, design was never performed even if one was possible, the following text was shown:
Bolts cannot be used with the current set of material selections. Invalid fastener geometry: check details.
For bolted connections, If Inset is selected as end type for orthogonal connections, and a non-zero value is set for the inset, the program claimed it cannot design, and continued to disallow design when another member end type was chosen.
An inset end type also was not preserved when you saved a file and reopened, regardless of the offset value, for main and side members. The value of the main member overhang was not preserved on a file save and reopen.
Nailed and wood screw orthogonal connections did not display the offset type upon reopening a file, but the connection diagram showed it and it refreshed when you made a change, and allowed design.
When Unknown was selected as the end type for Orthogonal and Skewed connections , the program would design connections that did not fit in the allowable space, or conversely fail to design connections that were permissible. The connection shown had dimension lines extending out of the drawing. These problems have been corrected.
The following problems have been corrected for the row shear resistance ( CSA O86 10.4.4.4) and group tear out resistance (10.4.4.5) features that were added for Version 8 of the program, and the new implementation of the tension, net section check (4.3.8.2 and 10.4.4.2).
For orthogonal and skewed bolted lapped shear connections with extended end types, the program does not perform the net section check or the group tear out check when it should, that is, for members in tension.
For the orthogonal connection, the program in this case issues a warning about a failed design due to the net section check, even though the amount of material removed is not in excess of 25%.
When the main member is the only one loaded in the orthogonal lapped shear connection, the program was not using the minimum of row spacing and end distance to calculate the value acri for row shear resistance and apgi for group tear out resistance, instead just using the row spacing. This created in non-conservative resistance values when the end distance was less than the row spacing.
When there is just one bolt per row on the group tear out and row shear checks for connections with extended end types, the program applied a wildly high resistance based on 10,000 mm end distance. Now, the Group and Row Tear out checks are not applied for these connections.
The end distance used for the calculations for bolted row shear resistance (10.4.4.4) and group tear-out (10.4.4.5) was the minimum end distance as input in the Details screen, rather than the actual end distance designed by the program. As a result the row shear and group tear-out resistance were almost always underestimated, which may causes over-design or failure to provide design to resist the applied force when a design exists.
For beam-to-beam and beam-to-column connections, the program sometimes reports a design failure for the face plate connected to the supporting beam or column, when in fact the design passed. This happens when there is significant horizontal (X-direction) loading on the supported side member such that the program has to explore connections that require more than the default side plate height, which is 35% of the height of the side member.