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Unless otherwise indicated, the following applies to input in all modes, Beam, Column, and Concept.
Load Types
Includes dead (D), live (L), snow (S), wind (W), live roof (Lr), storage live (Ls), impact (I) and earthquake (E) loads.
Storage live and Impact loads are not defined as such in the IBC or ASCE, but have been added to Sizer to deal with design code provisions relating to these circumstances. Impact loads have a different load duration factor (ASD) or time effect factor (LRFD), for glulam are subject to a 0.72 Cvr factor, and these loads are not patterned. Storage live loads have a different LRFD time-effect factor than other live loads and are treated as permanent loads in deflection calculations. Both types of loads are treated as live loads in terms of the load combination factors that are applied
Construction loads are to be entered as live loads, and you indicate that they are construction loads by using the check box "All live loads are construction loads." This applies the Construction load duration factor.
Live roof loads are restricted to 20 psf by IBC 1602.1; the remainder of the live load on the roof should be entered as an ordinary live load. A message upon load input prompts you to do this, changing the live roof load to 20 psf. Note that this limitation is not in ASCE 7.
Creating Loads in Beam and Column Mode
You must first specify one at least one beam span or the height of the column before the Loads button or Design Loads menu item becomes active.
After pressing the Loads button, you can enter a load name or let Sizer create a default name. Next select the load type (dead, live, snow, etc.) from the list. Next, select the load distribution (UDL, Point Load, etc.) from the adjacent list. This selection will determine what other fields will be active- the starting and ending position and magnitude of the load, the eccentricity of axial loads, or the tributary width of area loads.
Once all of the data have been entered, press Add to create the load. The load will appear in a list below the input fields along with all other loads on the member.
The diagram at the bottom of the screen displays all the loads in the list.
Pattern Loads
In Beam and Column modes, for live, live roof, and snow loads, it is possible specify whether each individual load is patterned - see Pattern Loading.
Repeating Point Load
In Beam and Column modes, the Repeating… button allows you to create a regularly spaced set of point loads of the same magnitude and type on a beam.
Concentrated Load Check
When the checkbox Add moving concentrated live load in Beam mode is checked, the program automatically adds a partial area load to the load list, and disables all other loads. The partial area load is a moving load that will be applied at intervals over the length of the joist. You can modify the magnitude of the concentrated live load and the area over which it is applied.
Note that if this is the first load you place on the member with will not be able to add another loads on the member. Load the member with other loads first and then check the Concentrated Load option.
This is possible for floor joists only. By default, the program applies a 2000 pound live load for over a 2.5' x 2.5' area.
Refer to Concentrated Load Check for more details.
Save as Default Load
Certain applications have a standard set of loads e.g. 40 Live, 15 dead floor loads, that are mandated by design codes and standards for certain types of buildings. This feature allows you to apply standard loads that are activated upon creation of new files and initial change of member type, to avoid the repetitive task of entering these loads for every new file created
When this button is pressed, the loads currently on the member are saved to a file, and are later applied when a new file is created of a type for which default loads exist, or if you subsequently change the member type (e.g. from Beam to Floor Joist).
The original default loads are removed and replaced with the default loads of the changed type. Existing loads that are not default loads remain and appear after the newly added default loads.
Other Input Fields
Refer to Loads Settings and Options and its subtopics, for descriptions of other inputs in the Loads View of beam and column mode.
Creating Loads in Concept Mode
For Concept Mode load input, see Create Loads.