ASDIP WOOD is a structural engineering software for design of wood members. It includes a module for multistory Shear Wall Design based on the latest NDS and SDPWS provisions.
But how do you enter the information in the program? How do you check the results? How do you optimize the design in a real-life example? The following is a step-by-step shear wall design example using ASDIP WOOD.
Shear wall example
As an example, consider the 3-story wood building shown below. Calculate the shear strength and determine the required size and number of the chord studs, using LRFD, for the first story shear walls. Assume dry service conditions and normal temperature range. The design loads include gravity and lateral loads as shown.
Shear wall geometry
In the Geometry tab enter the dimensions given in the statement of the problem, such as the story height and wall segment width, as well as the opening sizes. In this case we have three stories and three wall segments. Click on the database button to select the desired sheathing configuration, for example 19/32" wood structural panels with 10d nails @ 2". This configuration has a shear strength of 4080 plf for sheathing on both sides.
Go to the Studs tab to specify the stud size for sawn lumber western species. In this example we have selected 2x4 studs spaced at 12" along the wall segments, and 4 studs at each chord member, bolted together.
The At-a-Glance tab shows a summary of the results, with the most important information, for a quick overview of the design. If a deficiency is identified, it can be further investigated in the other reports which offer a more detailed information.
Specifying the material properties
In the Materials tab specify the material properties. Click on the Select from Database button to show the corresponding table of products from the manufacturer. Select Douglas Fir Grade No. 1 for this example. The program will transfer the material properties to the template.
ASDIP WOOD generates a condensed report in the Condensed tab, showing detailed calculations organized by topic in a tabular format This is excellent for a deeper check of the design as you go.
Enter the applied loads
Go to the Loads tab to enter the applied loads on the wall. In this case the loads are given in the statement of the problem as dead, live, wind, and seismic loads. Specify LRFD as the design method. Enter the following loads in the corresponding load case tabs.
Note that you can enter the loads at one story, say Story 1, and then copy these loads to all stories just with a click on a button. This will expedite the input.
ASDIP WOOD generates a detailed presentation of the results in the Detailed tab, showing step-by-step calculations organized by topic and load combination, with exposed formulas and references to the NDS code. This is excellent for a deep granular check of the design.
Optimizing the design
As you enter the information, the program calculates the shear strength of the system per story, and it compares it versus the story shear per load combination. In addition, the program calculates the chord axial forces in tension and compression per load combination.
Go back to the Studs tab and click on the Select from Database button. Select a section to be tested. The software calculates the adjustment factors for the different design conditions per the NDS and the product manufacturer. These factors affect the reference design values for the specified material. With this information the program calculates the design ratios for compression, bending, shear, and bearing. Finally it calculates the interaction for combined stresses.
Please note that the sheathing provides continuous lateral support to the studs in the weak direction, so the slenderness effects are calculated using the strong-axis section properties. In this example, the optimal chord section that passes all checks is (4) 2x4 studs. The user can select other preferred sections or materials easily from the database.
Takeaway
ASDIP WOOD includes the design of shear walls. This step-by-step design example shows how fast the design can be completed and optimized using ASDIP WOOD. The results are shown instantly in both text and graphics format for an immediate granular check.
For our collection of blog posts about wood design please visit Structural Wood Design.
Detailed information is available about this structural engineering software by visiting ASDIP WOOD. You are invited to download the Free 15-day Software Trial or go ahead and Place your Order.
Best regards,
Javier Encinas, PE
ASDIP Structural Software