The MiTek 20/20 repair tool is a good tool for improving turn around time. Repairs can potentially be turned around as quickly as seals. It can give the user an idea of what type, as well as how extensive, a repair may be. One major point that needs to be made is that all repairs still need to be reviewed by an engineer before being applied to a truss in case changes are required.
Using the repair tool is easy to learn. Users can take the materials that they have set in their individual lumber and connector files to do the repair. A very short amount of time will have to be taken to set the files up to include any lumber, gusset material, nails and or screws that the user prefers. After setting up these files, the user can input damage ranging from simple breaks and missing plates to sections of chords and webs or completely missing members.
You can also input notches and holes. The damage information can also be modified in the case where a measurement or size changes. Damage conditions can be removed from a truss in a situation such as having to change the wind criteria for the code used. Any manipulation in the original design of a truss requires all damage to be removed before making changes. Right click on the damage condition, the slide down to “Damage Condition”, then “Remove” as shown in the example here:
To input damage on a truss, simply right click on the member or joint that you want to apply the damage to. Go down to the damage condition selection, then add, and then you will see break, hole, notch, and damaged section if you are on a chord or web and you will see plate damage if you are on a plate at a joint.
This example shows what you will see when you right clicked on the peak joint:
When Plate Damage is selected you will be required to fill in the appropriate information as shown in this window:
Please note that the repair will be the same no matter what is selected in the damaged plate window.
This example shows what you will see when you right clicked in the middle of the diagonal web:
Simply fill in the appropriate information for the selection you made and click ok.
Please note that the program will only repair up to a 12” long break.
The following example shows the selection for a damaged section. This is sometimes used when there is a crack or breaks greater than twelve inches in length.
This example shows the required input for a notch.
This example shows required input for a hole.
Please note that all of the damaged sections will receive the same repair based on the full design forces in the member.
After you have all of the damage information applied, go to your toolbar and click Analyze/Go to see your repair results. If you do a print preview, you will see in bold letters, REPAIR(S) REQUIRED. Down below the drawing, in the notes section, you will see note 1 describing the damage condition and note 2 describing the repair instructions which will include lumber or gusset material, connector type and size, and the connection schedule as seen here:
You may occasionally see, “Damage condition(s) cannot be repaired.”
Do not be alarmed, this simply means that within the parameters given, the program could not calculate a repair. It could also mean that the materials or connectors that are required are not in the user’s files. As mentioned earlier, these things can be added but all damage has to be removed first. Regardless of which situation you may encounter, your engineer should still be able to produce a repair just as before.
If you have any questions on the repair tool contact your MiTek engineer.