Shearwalls:
Sizer:
Data Base Editor
The Shearwalls help files can not be properly viewed if the Windows operating system is one of Windows NT, Windows 98 or Windows 95. To obtain a copy of the help files compatible with these operating systems please do the following:
Download a copy of the self-extracting file SW_Help_NT_9x.exe to a permanent folder on your computer
Run this file (double click). A box will appear where you specify a temporary folder on your computer, and "Unzip" the file to that folder.
This will result in the placement of the files Shearwalls.hlp and Shearwalls.cnt in the temporary folder.
Copy these two files to the Shearwalls folder of your Design Office installation, replacing the existing files of the same name.
The problem could be the print driver. We suggest you download the most recent print driver for your printer. Using a different printer (if available on a network) may also resolve the issue.
If you are still experiencing problems with the newest print driver, do the following as a temporary work around.
Click Start / Printers and Faxes.
Select “Add Printer” and click Next.
Select "Local Printer" and click Next.
When prompted for port, highlight “FILE” and click Next.
Select "HP" as manufacturer, "HP LaserJet 4" as printer and click Next.
Select "Yes" for default printer and click Next.
Select "Do not share this printer" and click Next.
Select "No" to print test page, click Next and then Finish.
Start Shearwalls, open your project file and click the Run Design button.
When the Design Report appears on the screen, click File / Save Results As PDF.
Start Adobe Reader and open your PDF file (same file name and folder as Shearwalls file).
Print the PDF file using your actual printer and not the default printer.
To print the Log File or graphics, change the default printer back to your actual printer.
When you close Shearwalls be sure to change the default printer back to your actual printer.
Should the problem persist, or you have any other questions about the software, contact Woodworks® Technical Support at 1-800-844-1275.
Distribution of shear to shear lines based on the "rigidity" of the various shear lines is only relevant when the diaphragm is "rigid enough" (see building code for this definition). Flexible diaphragm analysis assumes that shear is distributed only by tributary area and therefore the force allocated to each shearline is not affected by a proprietary wall section.
By default for rigid diaphragm analysis (see WoodWorks® Settings/Design menu for other options) WoodWorks® approximates the "rigidity" of each shearline with its "capacity", or strength x length, instead of using deflection to calculate the actual rigidity.
Using the capacity method is recognized as a legitmate alternative in the 2000 IBC Structural/Seismic Design Manual - Volume 2, p67, Published by Structural Engineers Association of California (SEAOC) and edited by the International Conference of Building Officials (ICBO).
Once the shear is allocated to a shear line, however, the shear force can be distributed to each shear wall within the shear line based on the wall's rigidity (regardless of the diaphragm's rigidity) by checking the "Design shear force based on wall rigidity" located in the WoodWorks® Settings/Design menu.
Normally, proprietary walls are narrow sections not meeting the code required aspect ratios of 3.5:1, so stretching the proprietary wall to meet the ratio is a good approach.
Selecting the "Disregard shearwall height-to-width limitations" in the WoodWorks® Settings/Design menu would allow shear to be distributed to the proprietary wall product, but will also attract load to other narrow wall sections that may not be shear resisting.
Try to stretch the wall to simulate the correct relative "rigidity" approximated as "strength x length" compared to the standard wood walls. This way, the appropriate load is attracted / distributed to the shearline, and to the proprietary product within.
Generate and/or apply desired loads and run the design using the default "capacity" approach to determine the rigidity the software assigns to each wall segment. Print these results, especially the elevation showing the shearline that includes the proprietary wall. Ensure that the design results for that wall section are showing the rigid diaphragm results by first selecting the Loads and Forces plan view results (where you can also enter loads manually), then selecting the Show menu/Forces and select "Rigid".
An alternate method to stretching the proprietary wall in proportion to the relative rigidity of it versus the regular wood wall is to manually input relative rigidities. Under the "Shearwall Rigidity" in the Settings/Design menu, select "Manual input of relative rigidity". Then select the Walls button, highlight the desired wall segment and modify the Relative Rigidity fields in the Wall and Shearline Input dialog for the affected walls.
Rerun so the appropriate force is distributed to that shearline.
Run the Design, click the Plan View button, highlight the modified wall segment, click the Elevation View button and note that the shear is distributed according to the rigidities.
Delete all generated loads.
Apply the previously generated point load only to the proprietary product shearline, and adjust the previously stretched segments to the actual narrower width, and change the settings to ignore 3.5:1 ratio.
Run design again, print the new wall elevation. This new design will have the correct drag strut forces, base shear, and hold-down forces shown.
Click Settings/Design, and enter "0.9643" (which is 1.35/1.4) in the Seismic field under the Load Combination Factors section.
Enter "0.75" in the Seismic field under the Local Building Code Capacity Reduction Factor section
WoodWorks® U.S. Shearwalls generates ASCE 7 low-rise wind loads. The software calculates load cases for wind acting on any corner of the building. Once wind loads are generated, arrows will appear on the windward corners of the building representing the load case displayed.
Other load cases may be viewed using the Show button. To change the windward corner, select a direction in the Wind Reference Corner drop down menu that appears when you click the Show button.
The seismic reliability factor ? takes into account structural redundancy in the lateral force resisting system, and is used to modify any forces induced by horizontal earthquake loads as described in Section 9.5.2.4, pp 128-9 of ASCE-7 and Section 1630.1.1, p 2-13 of the UBC.
In general, this factor applies to buildings that are much longer than they are wide, or have very short shear resisting elements along the shearlines.
Applicable Seismic Zones
The application of this factor is restricted to UBC Seismic Zones 3 and 4, and ASCE-7 Seismic Design Categories D, E, and F. Shearwalls implements these restrictions.
Most heavily loaded element
The calculation of ? involves the shear applied to the most heavily loaded element on a story. Shearwalls considers an “element” to be a full height sheathing segment between openings.
Maximum Element-to-Storey Shear Ratio rMAX or r,
This is the ratio of the design storey shear resisted by the most heavily loaded single element, to the total design storey shear. For shearwalls, the ratio is modified so that concentrations of load in short segments result in a higher ratio.
Where: c1 = 10.0 ft, or 3.3 m
lW = the length of the element. Calculation of ?
According to UBC 1630.1.1 (pg. 2-13), and ASCE-7 9.5.2.4.2 (pg. 128)
where c2 = 20 ft, or 6.1 m
and A = floor area.
Limits for ?
Shearwalls limits this value to 1.0 and 1.5 in both codes.
Structure ?
Shearwalls implements the following methods:
The ASCE-7 method determines a maximum ? and floor area A for each floor to determine the ? value for that floor. The maximum ? value for all floors is then taken.
The UBC method determines the greatest ? for all floors at or less than 2/3 of building height, and then uses it and the base floor area A determine the ? value for the structure.
Design cases A separate calculation is performed for each direction of earthquake force, and for both rigid and flexible distributions.
Sequence of operations
The program calculates ? on each storey for the flexible diaphragm method, and then calculates a structure ? for the flexible method. It then redistributes the flexible forces to the shearlines with this ? value, designs the flexible method walls, and uses their capacity as relative rigidities for the rigid method. Finally, it calculates ? for the rigid method, applies this value to the rigid shearline forces, and designs the shearwalls for the rigid method.
This procedure relies on the fact that the value of ? will not effect the relative distribution of forces to the shearlines based on the flexible method, but does for the rigid method.
Display
The program displays the loads un-factored by ?, and the shearline forces factored by ?. It also displays a line on the screen, which indicates the ? value in the earthquake load combination. Design results
The program outputs a new Seismic Information table that lists Building Mass and Floor Area, as well as Story Shear, Shear Ratio rMAX, and the Reliability factor ? for each direction, each story and for the entire structure. It also displays separate tables for rigid and flexible design.
WoodWorks® Shearwalls provides default settings, however the user should verify the suitability of these settings and change them as required. Shearwalls includes a comprehensive Settings dialog box that is accessed by pressing the Design button in the data bar. It allows the user to control graphical interface options such as the unit format, font sizes, viewing area and snap increments; to specify design settings; and to filter what will be shown in the Plan, Elevation and Results Views. For each tab of the dialog box, there is a button to ‘Reset Original Settings’, and a checkbox to ‘Save As Default for New Files’ any settings changed by the user.
The Settings menu options are organized into eight tabs:
Design – Controls the engineering design options upon choosing a design code. The U.S. Shearwalls program has many design options and settings to provide design flexibility to the user. This flexibility allows the user to make design decisions in order to meet local building code requirements and to select the design methodology of choice. The Design tab of the Settings menu has pre-defined settings based on the model building code selected, however these values may be modified, and should be verified for their applicability in the jurisdiction you are designing for.
Default Values – Controls the default values for new files. Default values can be specified for member dimensions, self-weights for seismic building mass determination, roof geometry, site information for load generation, and the standard wall type to be used.
View – Controls the viewing area limits, the snap increment (it can only be decreased, and once decreased it can not be increased), and the intervals at which gridlines are displayed, if at all.
Format – Controls the unit format and the font size for the screen and printer output.
Options – Control the text to be shown in the Plan and Elevation Views, and the tables included in the Results View.
Loads and Forces – Controls the loads and forces to be shown in the Plan, Elevation and Results Views.
Company Information – Controls the input of company information to appear in the Design Results output for all projects.
Project Description – Controls the input of the individual project description to appear in the Design Results output.
Note that additional settings can be set with the data bar Show button. This tab should be used to adjust for the configuration of loads and forces you wish to view.
The group of settings on each tab can be saved as the default settings used by new files by selecting ‘Save As Default for New Files’. The settings that came with the program can also be restored using the ‘Reset Original Settings’ button.
In WoodWorks® Shearwalls, you can specify the maximum plan or elevation offset for walls to be considered on the same shearline.
These settings are found under Maximum Shearline Offset in the Design tab of the Settings menu. For example, the engineered design provisions of the IBC do not allow plan or vertical offsets. If you select the IBC, then unless otherwise specified, Shearwalls will use the values of:
Maximum Plan Offset = 0.5 ft
Maximum Elevation Offset = 0.5 Joist depths
The above values are recommended to provide tolerance for the automatic shearline generation routine. However, the software allows you to change any of these default values at your discretion. Note that a plan offset of 4 ft and elevation offset of 4 joist depths was originally included in Shearwalls based upon the prescriptive design provisions of the 1995 Wood Frame Construction Manual.
So what does this mean?
Maximum Plan Offset
Walls that are on the same level and separated by no more than the maximum shearwall plan offset will be considered to be on the same shearline. In this case, walls that are within 4 ft of each other will be considered on the same shearline.
In Plan view, you can quickly see which walls are on the same shearline by clicking on any wall. When you select a wall, all of the other walls on its shearline will be highlighted in purple. In the example shown below, wall 3-1 was selected and walls 3-2 and 3-3 appear in purple, since all three walls are within the specified 4 ft maximum plan offset from each other.
Maximum Elevation Offset
Walls that are on different levels will be considered to be on the same shearline as long as they are separated horizontally by no more than the maximum shearwall elevation offset, in this case 4 joist depths.
The first character of the names of the wall segments along the shearline indicates the shearline name. For instance, in the figure below, the second storey walls labeled 3-1 and 3-2 are on the same shearline as lower storey walls 3-1, 3-2 and 3-3 shown above.
In WoodWorks® Shearwalls, when you click the "Generate and Add to Loads" button on the "Generate Loads" form, a log file detailing the load calculations is created. The log file is saved under the same name (with extension .log) as your project file and in the same folder. To view the file, select "File" then "Log File" from the main menu. You can save the log file under a new name and folder, and open it with your word-processing software.
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With Caution. Shearwalls has been programmed to follow the codes with respect to code defined "regular" shaped buildings. Certain "irregular" shapes will not provide expected results, and engineering intuition will be required to determine if the results are acceptable for each situation.
An example of an L-Shaped building design is posted in the Support and Training section of this website. This shape is handled adequately by the software.
Caution must be used in the case of a gap between two walls, where the gap is actually external to the building such as in a U shaped structure (Refer to image). Two situations occur:
a) Where the walls are along the same shearline and separated by a gap, diaphragm shearline force/unit length is assumed to continue across the gap (even though there is no diaphragm external to the building at the gap) and drag strut forces are shown. In other words, the software assumes the gap is really an opening such as a window or door and can transfer shear across it.
b) Where the walls belong to two separate shearlines, (ie, the walls are offset from each other by more than the Settings/Design "Maximum Shearline offset, Plan" entry, the shear force distributes the shear force based on the tributary area associated to the wall.
As an example to the second case, considering only the walls in the east/west direction (see image), given a U-shaped building with a flexible diaphragm. Two north walls (C-1 and D-1) on either side of the gap are offset from each other by 6" such that they are on separate shear lines. The south wall (A-1) is 25 feet away. The central wall (B-1) is 10 feet from the two north walls:
Of the two northern walls, the wall furthest north (D-1) will receive a load based on a tributary area of only 3" (ie will receive almost no load), while the other north wall (C-1) will receive the other 3" of load + 120"/2 (the tributary area shared with shearline B-1) = 63".
"Main Wind Force Resisting System" (MWFRS) Design Wind Load Cases does Shearwalls Analyze
ASCE7-02 "All heights" method shows 4 cases that require consideration in designing for MWFRS, as per Figure 6-9 and Section 6.5.12.3.
Shearwalls accounts for Case 1 (full, non-torsional loading for each orthogonal direction independently) and Case 2 (partial torsional loading for each orthogonal direction independently). Shearwalls does not account for Cases 3 and 4 (with diminished loading in each direction simultaneously) which analysis showed would not govern for structures modelled by Shearwalls.
Distribution of shear loads based on a Flexible diaphragm analysis only uses the Case 1 loading, while for Rigid diaphragm analysis, both Case 1 and 2 loads are used. Both rigid and flexible design is done simultaneously, but it is up to the user to determine which distribution method is appropriate; the software does not do a direct comparison.
For the All-heights Rigid diaphragm analysis, the user must run the analysis engine two times in order to view results from case 1 and case 2. Switching between the two cases is done in the Settings/Design menu, and selecting either Case 1 or 2 under "ASCE7 all-heights wind load case for rigid analysis". In the future the software will do this comparison automatically.
The Low-Rise Rigid diaphragm analysis does not account for torsional load cases as described in Note 5 of Figure 6-10. Users are directed to the All heights method for torsional analysis.
The software also calculates the code required "10 psf minimum wind pressure" as per ASCE7-02 6.1.4.1. For the All-heights method, the software compares the wind generated loads with the 10 psf minimum pressure, and applies the greater of the two automatically. For the Low-rise method, the software generates loads based on either the 10 psf pressure or the wind speed generated pressures, but does not compare the results. Comparison was not possible with the low-rise method due to the end zone effects which can create different critical cases on particular shearlines.
The 10 psf minimum pressure can be ignored by de-selecting the checkbox in the Wind Load Generation dialog box. The All-heights method has the 10 psf minimum case selected as default, and the Low-rise method does not.
Typically, where design roof snow loads are less than 30psf, they are not required to be included in seismic load calculations. For higher roof snow loads, a percentage of the snow load is used to calculate seismic loads (20% for IBC (1617.5.1) and SPDWS (ASCE7-02 9.5.3) and 25% for UBC (1630.1.1). In fact, local building authorities may overrule the code and require up to 100% of the roof snow load to be used.
To include the correct snow load for seismic loads generation, input the total roof snow load and the percentage of roof snow load to be included in the Settings/Default Values dialog box in the "Weights for Seismic Load Generation".
In the "Generate Loads" dialog box, under the "Seismic Loads" column the total roof snowload entered in the Settings/Default values will appear with a note under it indicating what percentage of that load will be used to calculate the total roof self-weight for seismic purposes.
Remember to base the dead load and snow load on the horizontal projection of the roof. The snow load is considered to extend over the entire projected area of the roof minus the overhangs, as if it were a flat-roof load.
Note, that modifying the default values in the Settings menu requires the user to start a "New" file to take effect.
Glulam allows the manufacturer to place wood species in the lay-up to the material’s best advantage in resisting applied stresses. The whole premise of a glued laminated beam is that you are trying to put the high strength material in the extreme zones of the cross sectional member, so when the beam is loaded, the high strength material is located where the stresses would be the highest.
In an unbalanced beam lay-up, the grade and stress values for the lams on the compression side are not as high as the stress rating for the tension lams. Since wood is weaker in tension, higher strength material is placed on the tension lams than in the compression lams. This particular beam would definitely have a top and a bottom to it, and is popular in simple span applications. Thus, "Glulam Unbalanced" is used where the top is in compression.
In a balanced beam lay-up, the laminations that are used on the extreme ends of the section on either side are the same grade and stress rating. This means that this beam has no designated top or bottom and could be used in either orientation. Balanced beams are popular in continuous spans and cantilevers because of moment reversals. Thus, "Glulam Balanced" is used where the top is in tension.
In a uniform beam lay-up, the grade and stress values of the laminations in the compression zone, the tension zone and the inner zone are the same throughout. "Glulam Uniform" is used mainly for resisting axial loads.
The following website contains online courses on wood:
http://www.awc.org/HelpOutreach/eCourses
It may be that the actual size you wish to enter is the same as a nominal size in the Sizer database.
Example: if you wish to enter the full 2" width of undressed lumber, rather than the 1.5” planed width. Sizer will in this case select the nominal size when you type in the number "2". However, if you type in 2.01, Sizer will interpret this as an actual size, and even though it rounds the number and shows it as "2" the next time it updates, it will show just “in.” rather than “nom in” as the label and treat it as an actual size.
Prior to Sizer 2004 Service Release 1, installing a Windows 2000 or XP update from Microsoft would cause the logo to disappear from the Design Check output. This issue has been resolved in the most current release, Service Release 1. If you don’t have the most current release, please contact WoodWorks® Sales.
The Point of Interest button located on the toolbar is used to investigate the shear and moment at any point along the length of a beam or column.
A point of interest is generated by specifying a "Location from Left" to perform the analysis, and clicking “Add” to add this to your list. Several points of interest can be specified.
After performing a design, the results for the points of interest will be shown in the Diagrams window and in the Analysis results output.
Designers may require shear or moment forces at specific points of interest. For example, for many types of connections, designers are required to check the shear capacity of the member at the connection location.
WoodWorks® Connections provides the effective shear capacity of a wood member at a connection location. Using the Point of Interest function, a designer could determine the corresponding design shear force
Data Base Editor FAQs
To create a new custom beam database, follow the steps below:
Start WoodWorks® Database Editor.
Change Database Type to “Custom” and Member Type to “Beam”.
Highlight a Material and click the Add button.
Enter unique Material and File names. Check desired Material Type (use I-joist, if member selection is performed according to moment and shear capacities) and click on “Add First Species”.
Enter a Species Name, Weight and click Add First Grade.
Enter Grade Name, fill in all other fields and click Add First Section.
Enter Section size, fill in all other fields and click OK. Nominal Size is used for the pick list in Sizer.
To create a new custom beam database based on an existing custom database, follow the steps below:
Start WoodWorks® Database.
Change Database Type to “Custom” and Member Type to “Beam”.
Highlight the Material that is the basis for the new database, click the Save As button, enter a unique file name, and click OK.
Double click on the new material, change the material name to a unique name and click OK. Click the Use button.
Edit a Species by double clicking on the Species name. To add a new Species, highlight a Species name and click the Add button.
Edit a Grade by double clicking on the Grade name. To add a new Grade, highlight a Grade name and click the Add button.
Edit the Section by double clicking on the Section name. To add a new Section, highlight a Section name and click the Add button.
To create a new custom database based on an existing standard database, follow the steps below:
Start WoodWorks® Database Editor.
Select the desired Member Type from the drop-down menu.
Highlight the material to be copied.
Start a second session of WoodWorks® Database Editor.
Change Database Type to “Custom”, select the same Member Type as in the first session, and click the New button.
In the Material Name field, input the material name (14 characters or less), as you would like it to be displayed in Sizer.
In the Filename field, input a file name (14 characters or less) that is different from other standard or custom filenames of the same member type.
Check “Can be used in multi-ply members” if desired, modify CoVE as necessary, select Material Type, and click the “Add First Species” button.
Click Alt-Tab to return to the first session of Database Editor and double-click on the initial species of material chosen.
Click Alt-Tab to return to the second session of Database Editor, enter the species data and click “Add First Grade”.
Click Alt-Tab to return to the first session of Database Editor and double click on the first grade of species chosen.
Click Alt-Tab to return to the second session of Database Editor, enter the grade data and click “Add First Section”.
Click Alt-Tab to return to the first session of Database Editor and double click on the first section of grade chosen.
Click Alt-Tab to return to the second session of Database Editor, enter the section data and click “OK”.
Add additional species, grades or sections by highlighting an entry and clicking the “Add” button.
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