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Important Note – These are descriptions to changes implemented in WoodWorks Shearwalls for version 11 and may not reflect current program behavior.
If they are not indicated below, refer to Engineering Design, Design Settings, or Deflection Analysis sections of this document for physical explanations and design code references pertaining to the changes to the information presented in the Design Results.
The following new settings are presented in the Design Settings table:
The following setting has been removed from the program, so it no longer appears in this table:
The words Dry or Wet are placed after the moisture condition percentages.
For consistency with other cells containing phrases rather than numeric data, Shearwall relative rigidity is now in sentence case rather than title case.
The new input for serviceability wind speed for story drift calculations is shown in the Site information table.
A message regarding story drift referred to the Canadian NBC design code reference. This has been changed to ASCE12.12 for seismic design and ASCE 7 CC1.2 for the new wind provisions.
For walls with openings, the dimensions of the segments between openings now appear, in sequence with the openings at each end of the segments.
The length of segments within perforated walls is the value of Li defined as in SDPWS 4.3.4.3, that is, factored for the aspect ratio of narrowed segments.
Regarding the columns showing the full-height sheathing length:
Because the rules defining full-height segments are now identical for wind and seismic design, the program no longer shows two columns for wind and seismic design; only one value is now shown.
The length of full height sheathing displayed for perforated walls is ∑Li as defined in SDPWS 4.3.4.5 and 4.3.6.4.1.1, that is, factored for narrow segments using 4.3.4.3. This is explained in the legend.
A column has been added called Aspect Ratio, which shows the height-to-width ratio for wall segment, or walls when the entire wall is one segment.
Aspect ratios are shown for the segments in both perforated and segmented walls.
For walls and shearlines when no aspect ratio is shown, a short dash appears.
The legend has been modified in accordance with the new format of the table and information presented.
Occasionally, walls would appear out of order in the table. This has been corrected.
The legend now has consistent capitalization of leading words.
Shearlines no longer show a type, Perforated or Segmented, as there can be both on a shearline. Previously it was showing the first wall’s type.
Due to the increased importance of Aspect Ratio Factors with SDPWS 2015, if a segmented wall has openings, the program now shows shear design results for each full height sheathing segment in the wall. For each segmented wall with openings, lines starting with Seg. 1, Seg. 2, etc. appear after the line for the entire wall. They do not appear for perforated walls.
Note that the output described below for the table rows for individual segments also occurs for table rows for walls when there is only one segment on the wall and shearlines when there is only one segment on the shearline.
In the Show menu and the Options settings, a checkbox has been added to control the display of results by segments. If this is not selected, the program displays wall-by-wall results as before, except for improvements described in later sections.
The force values v and V, the interior and exterior allowable shear; the combined allowable unit shear and the total shear force V are shown for each individual segment.
For unsegmented wall-by-wall output, the wall row still shows the v values for the critical segment and the V values for the or the entire wall, which admittedly can be confusing.
For segment by segment output, the heading Crit. Resp has been changed to Resp. Ratio
as the response ratio for each segment is shown, and you must examine them to determine the critical ratio.
For unsegmented wall design, the old heading remains and the value shown is the one for the critical segment, i.e. the one with the highest response ratio.
The columns titled Asp/Cub (formerly H/W-Cub) shows the Aspect Ratio Factors for the segment, independently of the Unblocked factors, which will be shown in the row for the entire wall. For wall-by-wall output, the Unblocked and Aspect Ratio factors are multiplied together and cannot be discerned separately.
The following data are not shown in the segment line, as they are the same for all segments and are shown in the row for the wall containing the segments, or they are relevant to perforated walls:
Wall group (W Gp), vmax, Perforation factor (Co), Sheathing combination (C).
If there is zero force on the wall, the program does not show segments for that wall as there is no need to show detailed breakdown of force and resistance in each segment.
For segment-by-segment output when there are multiple segments in a wall, the data shown in the row for the entire wall are different from those shown in this row for unsegmented walls, as follows:
The value of v representing unit shear force is not shown, as it can differ for each segment.
The values of Co and vmax are not shown, as they are not applicable to segmented walls.
The interior and exterior allowable unit shear force are the ones unfactored by the Aspect Ratio factor or the Unblocked Factor Cub (In the rows for segments or for unsegmented walls, the factored capacities are shown.)
The columns titled Asp/Cub show only the Unblocked factors, not the Aspect Ratio factors, for each side of the wall. The Aspect Ratio factors are shown for in the rows for shearwall segments.
The combined allowable unit shear V is not shown, as the interior and exterior unit allowable shears are shown unfactored, and there is no design significance to adding unfactored shear capacities. The factored combined allowable shear force that is used for design can differ for each segment.
The design ratio is not shown as it differs from segment to segment, and it would be confusing to show some data on this line that were for the critical segment, and not others. Refer to the output for the individual segments for the critical design ratio.
The following pertains to the column titled "C" that indicates the rule used for combining sheathing capacities on opposite sides of the wall from SDPWS 4.3.3.3.
Due to changes in the interpretation of SDPWS rules to combine sheathing capacities on opposite sides of the wall, the letter G has been introduced to indicate the method in SDPWS 4.3.3.3.1 which uses apparent stiffness Ga of the walls.
As there are no rules in the SDPWS that specify you must use the strongest side only, this option has been removed from the list of codes. The symbol S is currently shown when there is sheathing on only one side, but in reality, no rule applies in this case. A dash (-) now appears.
The program now uses use the letter S for "strongest or twice weakest", eliminating the awkward use of the letter X for this option.
Because of the clarification to the SDPWS allowing for non-identical material specification for different walls on the line, all values except for the total ASD shear force V and the total allowable shear V can no longer be assumed to be identical for all walls on the line. If non-identical materials are allowed in the Design Settings, and there is more than one wall on the line, then in the Shearline row of the table, all values except for the two instances of V are removed and replaced with a dash (-).
The heading H/W-Cub changes to Asp/Cub, Asp standing for Aspect Ratio Factor, as per current SDPWS terminology.
The heading Total changes Cmb, meaning "Combined" as Total could mean total shear force for all segments on the wall, whereas the intention is the total of the interior and exterior allowable shears for an individual segment.
The columns headed by Asp/Cub have been moved to precede the Int and Ext columns in the Allowable Shear section. Previously, it preceded the shear force values to which it was not related.
Note that these values are included in the Int and Ext allowable shear, just as the Co factor is included in the combined allowable shear column that follows it.
Under ASD Shear Force, the V[lbs] column has been swapped with the v column for consistency with the Allowable Shear side of the table, and to place the more common v value before vmax, which is just for perforated walls.
For segmented walls, regardless of whether segment rows are shown, the values of Co and vmax have been changed to a dash (-), to show that they do not apply to these walls and to make the distinction between segmented and perforated walls more evident.
Previously, 1.00 appeared under Co and vmax showed the same value as v.
The following changes have been made to the row for the entire shearline when there is more than one shearwall on the shearline, otherwise the shearline row is treated as a wall row in the table..
Several data in this row were unneeded and difficult to decipher. The following outputs repeated the output of values for the critical wall on the line and have been removed and replaced with a dash (-): Aspect Ratio / Unblocked Factor Asp/Cub, unit shear force v, perforation factor Co, design ratio Crit Resp.
The Int and Ext allowable shear now shows these values unfactored by the Aspect Ratio and Unblocked factors. Previously it showed the factored values for the critical segment on the line. Note that the new behavior is consistent with the output of the row for the entire wall when wall segments are also shown.
Changes were made to the explanations in the legend in accordance with the revisions to the table described above, and to show updated SDPWS reference numbers and terminology also described elsewhere. In addition:
The description for vmax refers to the collector shear force, rather than just shear force.
The description of Co has changed from Perforation factor to Adjustment factor for perforated walls or perforated wall factor.
The Aspect Ratio Factor is no longer indicated to be specific to fiberboard for wind design.
In the explanation for combined (formerly Total) allowable shear, the unnecessary abbreviations int. ext. and inc. have been expanded to interior, exterior, and including.
The line explaining the meaning of the letters "W" and "S" after some response ratio values has been placed on the same line as the explanation for the response ratio, as it wasn’t clear what it pertained to.
If no blocking is entered for the interior side of a shearwall, it shows a blocking factor of 1.00 rather than the actual factor in the shear results table. However, the design capacity shown is factored correctly
Shearwalls were not always listed in order as they occur from west to east or south to north. This has been corrected.
The total shear resistance V shown in the shear results segments for a wall or shearline was the total force on all segments multiplied by the lowest aspect ratio factor, rather than the sum of the force multiplied by the aspect ratio for each segment individually. It thus understates the force on the wall.
As V is just output for your information and is not used for design, this was a display issue only. It has been corrected.
When perforated and non-perforated walls were on the same shearline, the force v shown in the shearline row was the highest force on any wall, but the allowable shear could be from a different perforated wall with a Co factor. Thus, the design ratio compared results from two different walls.
This was not a problem for non-perforated walls because for that case, all walls on the shearline had the same capacity.
It didn’t not affect shearwall design because the results that were used to design the shearwalls are shown on the shearwall row. The design ratio in the shearline row was just extra information and has been removed.
The reference to vmax in the legend was SDPWS 4.3-8 when it should be 4.3-9. This has been corrected.
The descriptions in the legend for shearline force has been modified to indicate ASD forces are now used for MWFRS wind deflections, and shows the load factors 0.6 D and 0.6 L.
The note for perforated walls now says that T from SDPWS 4.3-9 is used for the hold-down force, rather than saying it is factored by Co, and the note below the table has been expanded to explain the relation between T, Co and ∑Li, and where to find these values elsewhere in the output results.
The hold-downs were not always listed in order as they occur from west to east or south to north. This has been corrected.
When Applied loads are selected as the Collector force method, the legend to the drag strut table now refers to vmax from SDPWS 4.3.6.4.1.1 rather than the perforation factor Co.
Co was previously referred for both Applied loads and Shearwall capacity because using vmax was equivalent to dividing by Co, but due to changes in aspect ratio calculations for perforated walls, vmax now also depends on a variable ∑Li.
The drag struts were not always listed in order as they occur from west to east or south to north. This has been corrected.
Separate tables are now shown for Serviceability deflections and MWFRS deflections. A subtitle to each table explains the use of the former for story drift and the latter for force distribution for design.
The legend to the Serviceability table has been modified when compared to the MWFRS table to explain the serviceability wind loads Wa, the dead and wind load factors, and the factor used in the calculation of Ga for the 3-term deflection equation.
If the newly added 3-term deflection equation from SDPWS 4.2-1 is chosen, the Deflection table shows only one deflection value called Shear defl, rather than separate shear and nail slip deflection. The Ga value is also shown, and the Vn and en values for nail slip show the values at shearwall capacity vs or vw used to calculate Ga
The legend at the bottom of the table has been modified to reflect these changes.
The descriptions in the legend for shearline force v and nail force Vn have been modified to indicate ASD forces are used for MWFRS wind deflections.
The legend has been modified to indicate that the segment length b has been modified for aspect ratio factors, and that the shear force v used is vmax from SDPWS 4.3-9, as per 4.3.2.1.
This is not a new provision in the SDPWS, however, the definition of b and vmax now includes a variable ∑Li due to aspect ratio factors.
If there is any fiberboard in the structure, the legend indicates that, as per the new SDPWS provision 4.3.2.3, for segments with an aspect ratio greater than 1:1, the total deflection is multiplied by (h/b) ½. The value of this factor is not listed in the table.
Separate tables are now shown for Serviceability deflections and MWFRS hold-down displacements. A subtitle to each table explains the use of the former for story drift and the latter for force distribution for design.
The legend to the Serviceability table has been modified when compared to the MWFRS table to explain the serviceability wind loads Wa and load combination.
The descriptions in the legend for the uplift force P and fastener slippage Pf have been modified to indicate ASD forces are used for MWFRS wind deflections.
In the legend, it is now noted that for perforated walls, T from SPDWS 4. 3-8 is used for the overturning component of the uplift force P.
Extra spaces have been removed and missing spaces between words added.
A table has been added to show the Story Drift results for wind loads. It is a simplified adaptation of the one that currently appears for seismic design, showing the wind direction, max deflection on each shearline at each level, maximum allowable deflection, and the ratio between them. A warning appears if drift limits are exceeded on any line, with an asterisk beside the line failing drift ratio.
For some cases in which not all the wall design groups are standard walls, and when only one of rigid or flexible design is performed, the program output an extra row with 0 load and 0 capacity for each C&C result in the output table, and added wall design groups not related to any of the actual walls, also with 0 load and 0 capacity. These problems have been corrected
Occasionally, one of the diaphragm force Fpx values in the Seismic Information table would show a nonsensically high number. This was a rarely occurring bug due to unusual configurations of program memory, and has been corrected.
The following changes have been made to the log file header block:
Main Wind Force and C&C loads have been split into separate tables for readability. Previously there were two sets of headers for the tables and you had to correlate information for the type of load being read with the correct header line.
Pressing log file button for a new project displayed the results from the last unsaved session. The log file button is now enabled until loads have been generated.
The output of Site Information for seismic load generation has been made consistent with wind by removing the words "User Input" and placing it first in the sequence of information reported.
The Symbols table has been renamed Legend, consistent with Wind output
Where a subsection of the report contains more than one simple table, a blank line has been placed after the heading to the subsection to indicate that all the information below it pertains to that heading.
The Distribution of Base Shear to Stories table often appeared in a puzzling, ragged format because an earlier format with the stories arrayed horizontally was shown along with the current format with the rows arranged vertically. This has been corrected, and the following changes have also been made:
After generating low-rise wind loads on a structure with a flat roof, the log file would sometimes show nonsensical output for the rigid distribution torsional forces for low-rise Case B wind loads. As this case has a net zero wind load in the direction with nonsensical output, this did not affect design. It has been corrected.