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Design Settings
In the Design Settings Table, to reflect the changes in the Settings Input, Rigid Diaphragm Analysis is renamed Shearwall Relative Rigidity. The choices have been modified to be more explanatory. The new input field for deflection says Deflection-based stiffness of wall elements,
This corresponds to the new checkbox in the input Distribute Forces to Wall Segments based on Rigidity. If this is checked, it says Deflection-based stiffness of wall elements, if not it says Based on Wall Capacity.
Shearwalls Materials Table
Because of the need to add information for deflection design, the shearwalls materials table has been split into two tables, one for sheathing materials and one for framing materials.
For the framing materials table, only one line is needed for each wall design group, instead of the two needed for sheathing materials on each side of the wall. The fields that have been added are
A note has been added below the table saying
Check manufacturer requirements for stud size, grade, and specific gravity (G) for all shearwall hold- downs.
Storey Information Table
Columns have been added for the anchor bolt length and the length subject to shrinkage, as input in the Structure Input view.
Hold-down Displacement Table
A table has been added to show the components of vertical hold-down displacement da due to the main elongation, displacement, slippage, shrinkage, crush, and additional sources. It has the following fields.
Wall and Segment
The wall segment between openings is shown as e.g. B-3, 2 = second segment on Wall 3 on Shearline B.
Force Direction
E->W, N->S, etc. Can be “Both” if the data is identical in both directions because forces and hold-downs used are the same. In that case only one line is output instead of two.
Hold-down
The hold-down name from the database that is selected at the tension end of the segment. There is limited space for the name, so it may be truncated.
Uplift Force
The unfactored hold-down force at that location, including force transferred from floors above, and including the dead, shear and overturning components..
Elong/Disp
This gives the vertical displacement for hold-downs, that is, the combined elongation and slippage
Slippage
This input does not apply to the Canadian version of the program, and dashes (-) appear in these columns.
Shrinkage da
The calculated displacement due to wood shrinkage. The moisture contents appear in the legend below, and the length subject to shrinkage on each level appear in the Story Information table.
Crush + Extra
The value of wood crushing plus any additional components entered in the hold-down settings appears in one column. Although this column usually holds the same value for all segments, it is possible that at some locations the crush is zero because there is no compression force at the usual compression end of the shearwall.
Total da
The total vertical displacement for each segment, or sum of the displacement, shrinkage, crush, and additional displacements, is output in a column.
Hold-down deflection
The resulting horizontal in-plane segment deflection from the hold-downs, or da multiplied by the segment aspect ratio Hs/Ls, is output in a column. This value is then transferred to the Deflection table. ‘
Anchorages
For anchorages, in place of the displacement value, the program outputs, e.g.
(nu = 153 )
giving the value of the unit lateral nail resistance N from O86 10.9.4, needed in the equation for anchorages in 9.7.1.1.
Legend
The legend spells out the calculations that are used to arrive at each value, giving the value of any needed data not in the table such as percent moisture content and steel modulus of elasticity.
Deflection Table
Wall and Segment
The wall segment between openings is shown as e.g. B-3, 2 = second segment on Wall 3 on Shearline B.
Wall Group
The wall design group
Force Direction
E->W, N->S, etc. Can be “Both” if the data is identical in both directions because forces and hold-downs used are the same. In that case only one line is output instead of two.
Wall Surface
Some of the columns ( shear deflection and nail slip) have different values for different sides of the wall. To calculate them, different v values for each side of the wall are used as well. Therefore for each segment, if it is a composite wall, there are two lines output.
Wall surfaces are output as they are in the shear table, as Int or Ext for perimeter walls, and 1 or 2 for interior walls.
Shear v
The unfactored unit shear value on the segment ( that is, strength level shear for seismic design) is output. The proportion that goes into each side of the wall for composite walls is given.
This value depends on the distribution method input in the Design Settings, and when deflections are equalised, in many cases it can be zero. See .
Segment width L
This is the full length of the segment between the outside edges of the wall end studs.
Wall height H
Although this does not change for all segments within a level, it is output in a column as it is integral to the calculations.
Bending
For the bending component, the following are output on the first of the two lines for the wall segment:
Shear Deflection
The calculated shear deflection is output on both lines for the wall segment. The legend shows the calculation.
Nail slip
The following values are shown for the nail slip:
If the value exceeds the maximum value in the Table A.9.7, the maximum value is used. The program places an asterisk beside the value and issues the following warning.
*WARNING - Maximum load per fastener Vn from Table A.9.7 exceeded. Maximum Vn used but it underestimates actual deflection.
Hold-down Deflection
This value is transferred from the Hold-down Displacement table, where the components of hold-down displacement are given.
Total Deflection
Deflection from bending + shear + nail slip + hold-down, as per O86 9.7.1.1
Note that shear + nail slip should be the same for both sides of a composite wall, or else one side has zero force and the shear + nail slip for the other side is used. If his is not the case because the numerical procedure failed, the largest shear + nail slip is used.
Legend
The legend spells out the calculations that are used to arrive at each value, giving design code references and where to find data not in this table, e.g. the Stud modulus of elasticity in the Framing materials table.
Storey Drift Table
A table has been added to the program to show the storey drift calculations ASCE 7 equation 12.8-15 and the allowable storey drift from ASCE 7 Table 12.2-1. The allowable drift is shown for each level; the maximum storey drift for any shearwall on the level is shown on one line for each force direction below the allowable values.
Wall height
The wall height h is shown for each building level, along with the storey height hsx for that level, which is the wall height plus the upper floor thickness.
Allowable drift
The allowable drift calculated according to NBC 4.1 8.13 (3) is shown for each level only.
Amplification Factor Rd Ro
The value of the force modification factors Rd * Ro as they are used for the amplification in 4.1 8.13 (2), are entered on each line. Note that these values can be different for different force directions.
Importance Factor I
The importance factor I calculated from the Occupancy category entered in the sited dialog. This is the same for the entire structure, but is repeated in the table to show all variables for a calculation on the same line.
Maximum Deflection and Line
For each force direction on each level, the table shows the largest of the deflections on any shearline in the force direction as well as the line the maximum was on.
Amplified Deflection
The program shows the maximum amplified deflection on the same line.
Response Ratio
The ratio of the maximum amplified deflection to the maximum allowable is shown.
Failure Message
The program places an asterisk (*) beside any response ratio that is greater than 1.00. A red failure message appears below the table.
Legend
A legend has been added explaining each column in the table.
Table Legends
To all the above tables a legend has been added to the table or an existing legend improved such that it shows detailed information pertaining to each column on a separate line.
Show Menu and Display Options Toggles
For all the above tables, items have been added to the Show menu and the Display checkboxes in the Options settings that allow you to turn off the tables in the screen display and in the printed output, to reduce the volume of output, similar to all other tables.
Elevation View
Segment Forces
The force on each shearwall segment arising from the distribution of forces described in B: 3 above are depicted by small arrows at the top of the wall at each segment, with the force in pounds on that segment shown.