mudturk37
Structural
- Apr 9, 2009
- 3
I am referencing the 2012 IBC but I have checked the commentary for the past couple code cycles and it was the same in each.
Table 1604.3 Deflection Limits
The commentary states "In computing deflections to verify compliance with Table 1604.3 limits, the loads shown in the column headings of Table 1604.3 are the only loads that must be applied to the member......It is not necessary to use the load combinations of Section 1605.3 for verifying that the deflection limits have been met."
Lets assume a floor joist for example. Per the table, Live Load deflection is L/360 and Dead Load plus Live Load deflection is L/240. The column heading S or W simply has a "---" for the deflection for floor members.
Is it safe to assume that if you have a floor joist that may be supporting a wind or snow load, that you don't have to check deflections under those loading conditions, only strength?
For example, a floor joist(s) underneath an interior shear wall with an overturning moment applied midspan on the joist. In the past, I have calculated the joist with live and dead loads from floor loading in addition to the concentrated load from the OTM. In these cases, deflection is normally controlling. Have I been too conservative in the past?
Is it necessary to check the deflection limit against the deflection from a wind load?
Table 1604.3 Deflection Limits
The commentary states "In computing deflections to verify compliance with Table 1604.3 limits, the loads shown in the column headings of Table 1604.3 are the only loads that must be applied to the member......It is not necessary to use the load combinations of Section 1605.3 for verifying that the deflection limits have been met."
Lets assume a floor joist for example. Per the table, Live Load deflection is L/360 and Dead Load plus Live Load deflection is L/240. The column heading S or W simply has a "---" for the deflection for floor members.
Is it safe to assume that if you have a floor joist that may be supporting a wind or snow load, that you don't have to check deflections under those loading conditions, only strength?
For example, a floor joist(s) underneath an interior shear wall with an overturning moment applied midspan on the joist. In the past, I have calculated the joist with live and dead loads from floor loading in addition to the concentrated load from the OTM. In these cases, deflection is normally controlling. Have I been too conservative in the past?
Is it necessary to check the deflection limit against the deflection from a wind load?