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Sizer 8.11 – Design Office 8 Service Release 1a – March 11, 2009
This was an update due to the following problem introduced with Service Release 1 –
In Version 8.1 of the software, the live load component was not being transferred through any reaction in concept mode, that is,from beams, columns, or joists to supporting members.
Sizer 8.1 Design Office 8, Service Release 1 - Released Feb, 2009.
Starting with version 8.0, when point loads exist directly on top of supports, they were not being included in the bearing length design.
Starting with version 8.0, the unfactored dead reaction shown in the Bearing and Reactions output table was not including the self-weight.
I-Joist bearing design was not factoring the bearing capacity by the CD factor (NDS 7.32 and table 7.3.1; also AF&PA ASD Manual, Section M7.3).
The maximum "live" (non-dead) reaction displayed in the Maximum Reactions table of the Design Results was being affected by the determination of the maximum total reaction, so that occasionally the value shown was not the largest non-dead reaction. The program now reports the largest “live” reaction from any load combination.
When self-weight was set to "Manual" it was still being used in the calculations that determine maximum bearing length. The reactions reported in the Design Results were not including it, however.
Starting with Sizer 2004, the program was not considering the effect on shear from excluding loads at a distance “d” during the design search, so in some instances, passing designs could have been overlooked.
It was considering these loads when doing the full Design Check, so the shear response ratios in the Design Summary search were larger than the shear response ratio reported in the design check report when loads near supports are present.
The maximum number of plies available for built-up columns was mistakenly reduced from 5 to 4 in Sizer 7.1. This has been corrected; Sizer 8.1 allows 5 plies for built-up columns again, as NDS 15.3.1 allows for a maximum of 5-ply compression members.
The warning message that used to appear in the special Warnings section of the Design Check report in the case of 5-ply columns has been changed to read that these columns are not recommended, not that they are not allowed, and to refer to the design note for more details.
A design note appears under the same circumstances as the warning message described above. It says:
5 plies may be impractical due to NDS 15.3.3.1 requirement that all nails penetrate at least ¾ of the thickness of the last piece; a 5-ply 2x built-up column requires 7.125” nails. Nailing individual plies together with smaller nails has not been tested to determine if the published resistance values of the built-up member are achieved.”
This warning appears only when the column meets the following conditions.
The reason for the note is that nails long enough to comply with 15.3.3.1 are not practical and not listed elsewhere in the NDS.
The exclusion for full lateral support is because, according to 15.3.1, it is possible to design using the combined resistance of the individual members, which will be the case for full lateral support and CP= 1. So the requirements for nailing in 15.3.3.1 do not apply.
Note that the program does not attempt to prevent design with custom built-up ply sizes of less than 1.5” to comply, however an existing design note says that built-up members should be at least 1.5” mm to comply with 15.3.
The program now includes the moment due to eccentric column loads along with the side load moment in the design check for pure bending. Previously, the program was not including it because the bending value without eccentricity is needed in the design for combined axial, side load, and eccentric axial load design using NDS 15.4-1 and 15.4-2, and this was the only bending moment value the program was considering. The program now includes eccentric moment in its design for bending using NDS 3.3 as well as implementing 15.4-1 and 14.4-2.
The deflection results for the critical combination for each design criterion, live, and total are now shown in the Allowable Stress Design table. Previously, the deflection results for the critical load combination for the critical deflection criterion were reported for the other criteria as well.
Removed the setting Report dead load deflection from the Settings dialog. The dead deflection is now always output in the design report.
Starting with Version 8.0, when the moving concentrated load is added and is critical for design, the critical load combination shown in the Design Check results was always -1. This occurred for live and for total deflection. The load combination description is correct, and design is not affected in any way.
The Design setting Report interior and cantilever deflections separately can now be saved as default for new files
Changes to the Total Deflection Factor in Beam View would persist when a file is closed and an existing file is opened. Now, the newly opened project has its own factor.
For custom sizes of glulam columns less than 6" deep, compression parallel to grain resistance values are from the NDS Supplement Table 5B for sections with 4 or more laminations, when they should have been using the values for 3 and less. This has been rectified.
Title to Analysis vs. Design results section of the Design Check report did not include units for moment. Now the units for force, moment, and deflection are all placed at the end of the title.
The sawn lumber size factor CF is used in the calculation of Fb** in NDS 3.9 was not being output in the table of Modification Factors in the Additional Data of the Design Check report. It is now.
In the Additional Data section of the Design Check results, the modification factor table column heading “CL/CP” has been included for walls as well as for columns. Previously, it was showing just "CP" for walls. . "CL/CP” indicates that the table value in that column of the table is the column/wall lateral stability factor CP for axial design criteria, or beam/joist lateral stability factor CL for lateral criteria.
The program logic assumed that the custom load duration factors you enter in Load Input view are in the same order (in terms of magnitude) as the default values that come from the NDS 2.3.2. If the values were in a different order, the program may not select correctly the largest KD for any load in the combination. This could create a non-conservative error, but was unlikely to happen for any common load type. This has been fixed.
The Fire retardant checkbox has been disabled for SCL materials to comply with NDS 2005 2.3.4
Concentrated live load (safe load) previously applied only to floor joists, can now be applied to beams. The program assumes that the entire concentrated load that you input in the Magnitude field is applied to the beam, over the distance along the beam given in the Width field.
Entering more than 20 loads per span could sometimes crash the program or cause unpredictable results for load analysis. For version 8.0, Sizer restricted the user to inputting a maximum of 20 loads per span as a short-term fix. For version 8.1 this has been fixed, and the maximum number of loads per span is now increased to 100 loads per span. This limitation is imposed during user input of loads on the member.
In Concept mode, when a wall should have been supported by a joist area, and there were also joist areas below the wall on levels further down the structure, the wall carried through until it meets the lowest joist area, and was supported by that area instead of the one immediately below the wall. If there was a non-supporting joist area on a lower level, the wall was disqualified by that area, when it should be supported by the upper area. All walls are now supported by joist areas immediately below the walls. Note that this problem has always been in the software.
In the Maximum Reactions table of the Design Check report, the Dead and Live reactions included the load combination factors (for the critical load combination), but the value needed is the unfactored reactions, in order that you can transfer them to other members for analysis in Sizer without compounding the load factors.
Note that the “Live” reaction is in fact the sum of all non-dead load reactions – live, wind, snow, etc.
This applies to those load combinations that have more than one live, snow, or wind type. The program was applying the 0.75 factor according to load combinations 4 and 6 of ASCE 7 2.4.1 and IBC 1605.3.1 Eqns 16-11 and 1613. It also applies to the counteracting dead/ wind load combination with the 0.6 dead load factor (ASCE combination 7 and IBC Eqn 16.4)
The program now outputs these reactions unfactored. In order to make this more clear, the row headings "Unfactored" and "Factored" have been added to the Reactions table for dead and live reactions, and total reactions, respectively.
The load previously referred to as "Live” has been renamed "Other" because it in fact contains the sum of live, wind and snow loads..
For the IBC and ASCE-7 choices of load combinations, the load combination 1.0D + 1.0W, corresponding to equation 16-12 of IBC 2006 1605.3.1, and combination 5 of ASCE 2.4.1, was not implemented by the software. Only the counteracting combination 0.6D + W was implemented.
This load combination was introduced in the 2002 version of ASCE-7, so should have been implemented by the 2004 version of Sizer for the ASCE 7, It was first included in the IBC 2006 version, so should have been in version 8.0 for the IBC choice.
What were previously referred to as "Constr." (construction) loads , with symbol C, are now referred to as Roof live" loads with symbol Lr, and are given the the load duration factor CD for live loads (default: 1.0) rather the one for construction loads (1.25). This change has been made to properly implement load combinations in ASCE 7-05 2.4.1 and IBC 2006 1605.5.3.1 containing Lr loads.
To accommodate construction loads, a checkbox has been added to the Load Input view allowing you to indicate that all live loads are to be interpreted as construction loads and given the construction CD factor, which defaults to 1.25 from NDS 2.3.2. These changes recognise that, according to the provisions in IBC 1607.11 and ASCE 7 4.9, live roof loads are not equivalent to construction loads. However, this implementation does not allow you to design for construction and live occupancy loads simultaneously. Future versions of Sizer may allow for this if there is a demand for it.
When the construction box is checked, all live loads are renamed "Construction" loads and Live roof loads are named "Roof constr." loads, but they retain the L and Lr symbol. The "C" symbol is no longer used. The changes to nomenclature are made wherever these load type names and symbols appear in the output, for example the analysis results say "L= Construction" when the box is checked.
The program now treats Impact loads as any other live load for the purposes of generating load combinations, for all choices of load combination design code. Previously, for IBC, Impact loads were not being combined with Construction loads in order to implement Exception 1. of IBC 1605.3.1 regarding the combination of roof live loads with crane hook loads. (Refer to a) and b) above for the changes to live roof/construction loads). This change recognises that according to IBC 1607.8 and 1607.12, crane hook loads are not equivalent to impact loads, and some impact loads might legitimately combine with live roof loads, as those from an elevator.
Load combinations containing impact loads continue to be given the load duration factor for impact loads, which defaults to 2.0, from NDS 2.3.2,, from and Impact loads continue to be given the symbol I
Exception 1 of IBC 1605.3.1 for crane loads is no longer implemented in the software, as crane loads are rare on wooden structures.
Note that changes D and E means that the load combinations generated using the IBC and ASCE 7 choices of load combination design code are now identical.
The load combination factor in Sizer for ASCE 7 impact loads when combined with wind loads and with construction (now live roof) loads, was 1.0, when it should be 0.75 according to ASCE 7 section 2.4.1, load combination 6, considering that impact loads are a type of live loads according to ASCE 4.7. The load factor has been changed to 0.75 for this combination.
Sizer did not create Construction pattern load combinations when snow loads are present, instead creating only the snow pattern combinations, even though construction patterns were created when there is no snow on the member. The program now creates patterned load combinations for Roof Live loads, which have replaced Construction loads in those combinations (see Bug 1864, above), in all circumstances.
When repeating point loads are added and a repeating point load is created directly over top of a support, sometimes the point load was incorrectly being included in the shear analysis values and also therefore the moment values. The load drawing would also show these loads as contributing to the point load over other supports than the ones they were on.
The program now includes the moment due to eccentric column loads In the Analysis diagram and in the Analysis results.
Previously, the program was not including it because the bending value without eccentricity is needed in the combined axial, bending, and side load design, using NDS 15.4-1 and 15.4-2, and this was the only bending moment profile the program was considering.
After opening a concept mode project that was created with a previous version of Sizer in version 8 USA, when a load was selected, Sizer was crashing. This has been fixed.
Starting with version 8.0, attempting to enter an Impact load on a member was creating a Hydrostatic load instead, even though Hydrostatic loads are not included in the USA version of WoodWorks Sizer. Attempts to enter such loads create instabilities in the software.
Starting with Sizer 8.0, in Concept Mode, live loads applied to roof were changing to dead loads when focus was no longer on the load.
Trying to add a triangular load with zero magnitude at the end point caused an “invalid load location” message and the load was not created.
When point loads were added in Beam or Column Mode Load Input view, with Force set to Kips in the Format Settings, the program interpreted the input as pounds, despite showing Kips in the label. It showed the equivalent number of kips in the load list (input divided by 1000). This has been fixed.
Upon changing Material type, the Service conditions, Fire-retardant, and Temperature (T) input fields were being reset to default values. They now persist through a change of materials.
In Beam Input view, when a range of widths are selected sometimes extra duplicate depths are listed in the depths combo-boxes.
Corrected typos in Building Codes box that is invoked from the Welcome to Sizer dialog box (question marks and misplaced "Design" )
Restored comment about Fire design using NDS 2001 not being implemented by Sizer.
Using metric units, the concentrated load combination name, which includes the location of the load, was expressed in whole numbers, with 0 digits after the decimal place. It now has two digits, so that a name that was previously "Lc@1” is now “Lc@1.47”.
When there is only self-weight on a member and no other dead loads, the concentrated load combination symbol in the Analysis output showed only the concentrated load, not the dead load. This has been corrected.
When the information in a concept mode output report exceeded the height of the screen, no scroll bar was present.
You can now choose to turn off the display of wood textures on the beam diagram separately for screen display and printed output, as some printers malfunction when trying to display the textures. The default setting for printed output is to have the textures turned off, and for screen output, to have them on.
When a range of more than one depth is entered in beam view, the Beam Drawing in Beam Mode was showing a beam that has a depth equal to the minimum depth entered. It now shows as a thin line as if the beam depth was unknown.
Notches were being drawn too long in the beam diagram so that a space appeared between bearing and notches when the notch should have been the length of bearing. This was increasingly so for larger notches.
The deflection diagram for columns no longer shows negative numbers, which have no meaning for columns.