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Important Note – These are descriptions to changes implemented in version 10 and may not reflect current program behaviour.
The program now includes a database of Simpson Strong-tie joist and beam hangers, allows you to select these hangers as the bearing support member, and automatically selects a hanger if you select Unknown.
The hangers are selected from a database program provided by Simpson, which is incorporated into the Sizer installation.
Because Simpson hanger strength depends on the species of material, a new input called Species Group has been added to the Species dialog of Database editor, allowing for input of one of D.Fir-L, Hem-Fir, Spruce-Pine-Fir, Northern.
For I-joists, the input is called Flange species.
For structure composite lumber (SCL), the input otherwise used for Species group is called Type, and offers the choices LVL - DF/SP, LVL – SPF, PSL, and LSL.
The proprietary Sizer material database files from Louisiana Pacific, Weyerhaeuser, Boise (VersaLam), and Forex have been modified to set this value set to the appropriate choice.
All inputs for this have been added to the Supports for Bearing Design data group.
Simpson hanger has been added to the support Type input list. The existing Hanger choice is renamed Other hanger.
Simpson hanger is not available if the main member is Steel or if it is a glulam or lumber file material with Northern species, as Simpson does not publish values for Northern species members.
Simpson hangers are not available for oblique members.
The selection of Simpson hanger applies to end supports only, and selection and design will be done only for end supports only. If All supports or any other selection that includes interior supports is selected, then then ordinary Hangers are used for the interior supports.
The Material changes to Header when Simpson hangers are selected, shows materials from both beams and joists. Steel members are not included in the list.
Will show the species for selected Material, as it currently does. Northern Species is excluded from the list. Hem-fir is treated as if it was SPF, as Simpson has values for Doug-fir and S-P-F only.
The Grade field is retasked to show the section sizes for the selected species, in a b x d format.
Bearing at support end is invisible.
A checkbox indicates that the header is a ledger, which is a member assumed to be affixed to a hard material such as concrete so that nails in the face flange cannot penetrate more than the member thickness. It is active for lumber and SCL materials only.
A checkbox indicates that the header is a nailer, which is a member assumed to be affixed to the top of a member of another material such as a steel I-beam, so that they lie on the flat rather than upright like other members.
Bearing length is disabled and shows Unknown when the hanger selection is Unknown, and the hanger bearing length from the Simpson database otherwise.
Bearing width is disabled and shows Same as beam or Same as joist.
These inputs are unaffected by the hanger selection.
This data group will be renamed Hanger options. All existing inputs are invisible when Simpson hangers are selected. The inputs described below are included instead.
An unlabelled input box has the selections All, Face mount, Top flange, used to filter the hanger list returned by the Simpson database program.
The model input lists the available hanger models given the selections for main member and header, ordered by the cost index value supplied by Simpson.
It is headed by the choice Unknown. Only Unknown will appear if any data needed to select the hangers are not available, such as main member size or no. of plies.
For sloped members, the program lists appropriate angled hangers, showing Simpson’s special information code like SLU5, meaning 5-degree upwards slope.
The fasteners list box used to distinguish those hanger models that have different capacities for different fasteners used on one or more of the flanges of the hanger. It is only when a hanger is selected that has this situation, to allow you to differentiate the repeated hanger model.
The fasteners are designated as Face, Side, or Top, according to which of which of these flanges have differing fastener specifications. If two or more of the flanges have different fastener selections, then the following precedence is used \-Top, Face, Side.
The unfactored capacity and the cost index of the selected hanger will be shown in text fields labelled Capacity and Cost index, respectively in the remaining space in the Hanger options box. This will aid in testing design for unknown hangers, but will also be useful information those . who want to select their own hangers
The program factors the Simpson hanger capacity by duration factor KD and uses that as the bearing capacity for both supported and supporting member.
This value is not used to determine the minimum required bearing length; for this the member is considered to be supported by a generic hanger or a "non-wood" member; i.e. as if it were supported by a steel plate.
The Simpson database capacity includes the KB factor, so Sizer does not calculate or apply a KB factor.
For those load combinations that have an uplift reaction on one or more of the Simpson hanger supports, the program compares the factored uplift capacity to the factored uplift load. Note that it is only Simpson hangers that have uplift design.
When Unknown is selected, the program will cycle through all possible fasteners in order from lowest to highest cost index, until it finds one that passes both the uplift and the bearing design criteria.
After a hanger is selected, the bearing length determined by the flange length B of the hanger and the calculated minimum required bearing are used to determine a new design span, and the beam re-analysed and designed
Under the beam material specification, for each support with a distinct Simpson hanger, a string of information is output giving the model number, a special information code giving for example the angle of the hanger used for sloped members, the fasteners for each flange, and, if necessary, whether backer blocks or web stiffeners are required.
In the Reactions and Bearing table, the fields for KB, KB support, fcp sup , and Kzcp sup are irrelevant an disabled. The support resistance shows the factored resistance of the selected hanger. The Length shows the length B of the bottom flange of the hanger.
If any of the supports with a Simpson Hanger experience uplift, then rows are added for Uplift resistance and the KD factor used for the critical uplift load combination.
If the program fails for uplift design, a new design criterion is added to the red failure warning message in the Design check output called Uplift restraint.