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Additional FAQ drafts for section cut FAQs are availablelisted onin the [Section cut FAQ DRAFT|kb:Section cut FAQ DRAFT] pagearticle.
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This page containsis devoted to *frequently asked questions* (FAQ) related to *[section cuts|kb:sectionSection cut]*.
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h1. General FAQ

h2. Can the program display force diagrams be baseddisplayed onfor a sequence of section cuts?

*Extended Question:*: I have developedmade aand 3dsaved sticksection modelcuts of a slab bridge with along the uselength of shell elements to model the a bridge slab. Can I have made and saved various section cuts through the slab and wanted to view the shear and bending -moment diagrams withfor quantitativethis values.series Isof thissection possiblecuts?

*Answer:* While there is no built-in capability within the program to display shear and moment diagrams for aThis series of section cuts (as of SAP2000 V15.0.0 and CSiBridge V15.1.0), you can obtain these diagrams outsidemay ofbe the programobtained with some additional pre-processing and post-processing.

(1) Use, described as follows:

# Define multiple section cuts using [interactive database editing|kb:Interactive database editing] (", available through Edit > Interactive Database Editing") to conveniently define multiple section cuts. TheData datamay can evenalso be imported from Excel in which you can setup formulas to automate defining the sections cuts at desired intervals along the span.
, where section-cut data may be automated over a series of intervals. These controls are shown in Figure 1:
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!Section_cut_definition_tables.png|align=center,border=0!
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{center-text}Figure 1 - Section-cut 
(2)definition tables{center-text}
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# Run the analysis and use ", then display section-cut forces in tabular format by selecting Display > Show Tables > ANALYSISAnalysis RESULTSResults > Structure Output > Other Output Items > Section Cuts > Table: Section Cut Forces - Analysis" menu command to display the section cut forces in a tabular format. Then you can export the .
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# Export data to Excel for post-processing and plotting theof momentshear and shearmoment diagrams.
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This may require significant effort if done manually, but it would be a reasonable approach if it is automated using using macros, some \\
Macros, basic programming, or the [Application Programming Interface|kb:API] (API). Themay discretizationhelp shouldexpedite bethis refined as needed in orderprocess. [Discretization|kb:Discretization] should be refined to adequately define the section cuts.

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A new feature, is planned (collection of section cuts along a line) that, is in development. This control will enable you to do thisthe plotting of response quantities for a series of section cuts within the programsoftware interface.
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h1. Section Cutcuts Defineddefined by a Cuttingcutting Planeplane

h2. What is the orientation of the positive 3 axis offor quadrilateral forelements quadrilaterals located in the vertical plane?

*Answer:* The positive 3 axis refers toof quadrilateral elements follows the same positiveconvention 3as axisthat of the quadrilateral, using the same convention as for shell elements. Therefore, the positive 3 axis is always uniquely defined. {verify}for [shell|kb:Shell] objects, where axis orientation is normal to the element area, and positive projection aligns with the cross product.


h2. Can I define the cutting plane be defined through any joints?

*Answer:* If possible, the cutting plane to cut though any joints?
 should not pass directly through [joints|kb:Joint] such that the software may determine the side of the cutting plane on which joints are located. For section cuts defined by a quadrilateral cutting planesplane, [SAP2000|sap2000:home] calculates the section -cut forces by summing the element joint forces fromwithin the frame[frame|kb:Frame], [shell|kb:Shell], and [link|kb:Link] membersobjects thatwhich are fullyentirely cutwithin by the cutting plane and included in the group that defines the section-cut cutgroup. The joints that are Joints considered areinclude those thatwhich (1). belong to the section -cut group; (2). are assigned to objects entirely within the fullycutting cut elementsplane; and (3). are on the specified side of the cutting plane.
In
order for the program to determine on which side of cutting plane the joints
are, the cutting plane should not directly pass through any joints, if possible.

h1. Section Cutcuts defined Definedusing inthe Graphicalgraphical Useruser Interfaceinterface

h2. The magnitude of the Integrated Forces for the right side is different fromWhy is the magnitude of the integrated forces different for the left and side.right Whysides?

*Expanded Question:*: AfterAccording usingto "Drawequilibrium, > Draw Section Cut",should not the magnitude of integrated theforces Integratedbe Forcesequivalent for theboth rightleft sideand isright differentsides?
from
the magnitude of the integrated forces for the left side? Based on equilibrium, should not the magnitude of these two sets of forces be the same?

*Answer:* The section cut forces on the left side and on the right side can be different, because the section cut forces are based on the forces at the joints (of the element cut by the section cut) at each side of the section cut. Create simple example of cantilever wall with two member and determine the section cut forces at the middle of each member.

h2. When *Answer:* Section-cut forces may be different on either side of a [section cut|kb:Section cut] because they are based on joint forces which occur in the global system. Globally, these forces are in equilibrium, but their relation to a section cut is arbitrary and does not necessarily serve the function and conditions of a free-body diagram.

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h2. How is the plane of the section cut defined when drawn in a 3D view?

*Expanded Question:* When a section cut is drawn in a 3D view, only the X and Y coordinates are provided. How exactly is the section -cut plane defined?
for
this case?

For*Answer:* When using the "Draw > Draw Section Cut" menu command, the forces are reported in the [section-cut|kb:Section cut] coordinate system, which is defined by three axes (1,2,Z) as follows:

* section Section-cut 1 axis is located inwithin athe plane thatparallel isto parallelthe with global XY plane; it is rotated by user-specified "X-Y plane, and rotates counterclockwise from the global X axis according to the user-defined parameter Angle (X to 1)" counterclockwise from.
the
global X axis
* section Section-cut 2 axis is also located inwithin athe plane thatparallel isto parallel withthe global XYX-Y plane;, though it is rotatedoriented 90 degrees90° counterclockwise from the section -cut 1 axis.

* section Section-cut Z axis is parallel to withthe global Z axis.

Integrated forces are reported either on the left side or on the right side of the section cut using, according to the right -hand rule. Take, Forfor example, if thea section cut is drawn infrom aleft horizontalto planeright fromalong leftthe tohorizontal rightplane inwithin ana XZX-Z view,. thenIntegrated integrated forces on the left side represent the effect from the structure behavior above the section cut, while expressedthose inon the section cut (1,2,Z) coordinate system, using right hand rule. Similarly, integrated forces on the right side represent the effect from the structure below the section cut, expressed in the section cut right side, below. Using the right-hand rule, these forces are expressed in the section-cut coordinate system (1,2,Z).
coordinate system, using right hand rule. {verify}
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h2. ForWhy draware section cut option, why are the-cut integrated forces shown in 1, 2,Z and Z directions? Why not 1, 2,3 anddirections?
3?
*Answer:* For the section cuts drawn inwithin the graphical user interface, the section -cut 3 axis is always parallel withto the global Z. Thereforeaxis, thetherefore integrated forces are shown in 1, 2 and Z directions. {verify}
2,Z directions since this notation is more precise.

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*Related incidentsIncident:*

* {incident:no=41578|comment=Section cut results for response spectrum analysis}
** {email:date=1/12/2012|from=ok|to=hf|subject=Section cuts for response spectrum load case|comment=|id=8094858}
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