Frame Generation Menu

 

The frame generation menu appears and gives you the option to pick a basic frame as the starter for creating your own frame.

 

The various starter frames include:-

 

Grid lines – set up a series of orthogonal grid lines as a basis for a new frame

Floor Plate – plan floor layout which can be easily copied up into a 3D frame

Snap Grid – draw a series of structural elements manually

Simple Beam – an easily set up single beam

Continuous Beam – multi-span continuous beam

Sub-Frame – useful for analysing a part of a structure

Multi-Storey and Grillage – elevation of a multi-storey frame which can be copied horizontally into the 3rd dimension, and plane grillages

Multi-Portal – used to generate single or multi-bay portal frames

Tower Frame – 3D tower frames and domes

Roof Truss – 3D roof truss

Fink Truss, N Lattice and V Lattice trusses – starter trusses

 

Each of these basic frames can be quickly modified to suit your particular frame layout and copied upwards or horizontally to create a 3D frame.

We recommend starting with one of these frame pre-processors as this is usually easier than starting a model from scratch.

 

 

Grid Lines

 

See – MasterFrame Space Frame > Creating a Model > Grid Lines > Grid Line Wizard for full explanation.

 

 

Floor Plan

 

Initially a plan view of a floor plan appears on screen along with a side panel where the floor layout can be defined.

 

 

It starts with 9 bays in the X direction and 3 bays in the Z direction, with the X spacing defined as 3m and the Z spacing as 9m. If you drop the down arrow next to the X 01 line you will display all the X bay spacings, which can then be altered where required so that all spacings can vary in the X direction. The same can be achieved for the Z spacings.

The Y level for the floor can be defined. This initially starts off at 3.5m so that columns can be later added below this first floor level.

The Grid Spacing X and Z allow you to space the gridlines in both the X and Z axes. For example, the X gridlines are spaced at 1;3 meaning the first grid will start at line 1 and the next grid a further 3 lines across, as shown above. In the Z direction the gridlines are spaced at 1;1 meaning the first grid starts at line 1 and the next one line along and so on.

The gridlines can be skewed in one direction using the skew angle option. You can also select the box to allow the X grids to change from numbered to lettered – Grid X .. A,B,C. The direction of the lettering or numbering can also be reversed for both X and Z grids.

 

You can select the type and size of basic section that you want to start the frame off with. These can be steel, T-shaped concrete, rectangular concrete or rectangular timber. The orientation (beta angle) of the members can be defined. They will normally sit at 0 degrees, major axis vertical.

 

Origin and orientation.

By clicking on the Origin and Orientation button you can manipulate the position of the frame. This isn’t usually necessary when initially starting a frame but can be used later to resize, shift or rotate the frame or when importing another frame into the existing frame – see ‘Modifying Geometry - Change Coordinate Tools’ and ‘Creating a Model – Add Frame – Import a Frame’ in the main MasterFrame manual for details on how to use these options.

 

Preview & Apply

The Frame Data button will take you out of the Origin and Orientation option, back to the original input panel. You can always Preview the changes before Applying them if you are happy with these changes.

 

 

Snap Grid

 

See ‘MasterFrame – Creating a Model – Add Members (General)’ in manual for explanation of right hand ‘Define Members’ panel.

In the bottom right of the graphics area there are several icons which relate to the snap grid. These are:-

          Snap grid – on/off

          Show CAD Layer – your view must be on the CAD Layer plane

          Object Snaps – on/off – right click for quick settings

          Polar Snaps – on/off – set the polar angles in settings

          Snap settings – snap grid, object snaps and tracking

 

 

Snap Grid Settings

For further details see Object Snaps and Snap Settings Setup

 

Snap Grid General Settings:-

The first tick box allows you to switch on/off the snap grid. The grid spacings can be set in metres. If equal spacing is ticked then the snap grid will be square, otherwise you can set different spacings in the 2 directions. Also see Snap Grid Spacing

 

Snap Grid Plane Settings:-

You can select which snap grid plane you wish to display – XZ, XY or YZ planes. The fourth option allows you to set a plane that is not in any of the 3 orthogonal planes by specifying angles in the options below. The red X button sets the snap grid origin back to 0, 0, 0. Alternatively you can specify an origin using X, Y and Z coordinates or pick an origin position off the existing frame.

In-Plane/Off-Plane Settings:-

When any of the Snap Grid Plane axes are chosen, you can offset the grid from the chosen plane using the Grid in-plane rotation (degrees) option, eg, 45 degrees will rotate the plane from the original plane position through 45 degrees.

When the 4th button along in the Snap Grid Plane Settings is in use, the grid can be offset from the 3 orthogonal axes using the off-grid rotation (rotates the grid about the Y axis) and off-grid angle (set angle between grid and vertical) options.

The bottom option to Set in-plane grid angle (two points) allows you to graphically pick 2 points to set the snap grid angle and/or plane.

Also see Snap Grid Orientation

 

Object Snaps Settings

 

 

Member / Line Snaps On:-

The Object Snaps settings dictate to the program which snaps are on or off when using functions such as Add Column or Add Member. Most of these are fairly self-explanatory.

You can snap to a point along a member or on a tracking line projecting from the member along its length. You can snap to third or mid points along a member and set a snap spacing default dimension.

You can also set new members perpendicular to existing members or orthogonal to them or have them snapping to grid line intersections.

Show and Snap to CAD Layer:-

If CAD Layers have already been added to the model, you can select which layer to make active.

Also see Snap Points

 

Tracking Settings

Also see Tracking Lines and Points - 2nd end of member and

Tracking Lines and Points - 1st end of member

 

Polar Tracking On:-

Polar tracking can be used to position end nodes of members. There are a set of common angles or you can set your own custom angles where required. Polar tracking lines can also be used. These usually adhere to the nearest principal plane.

Also see Polar Tracking

 

Tracking Settings:-

A number of additional tracking possibilities can be switched on to aid placement of members.

Also see Parallel Tracking and Top Level Nodes

 

 

Simple Beam

 

 

In the simple beam starter frame, you initially see a beam with no section size or loadings. The section type and size can be set and the beam length and loading applied as set out in the MasterFrame manual in the Properties > Member Sections and Materials section and the Loads > Member Loading.

 

 

Continuous Beam

 

 

The number of spans can be defined along with a default span length. The droplist of spans allows you to select a particular span and change its length. A general dead and live loading can be added. This can be specified in kN/m2 and a spacing perpendicular to the beams entered to produce a UDL on the beams. Alternatively, set the spacing to 1.0m and enter the loads as line loads.

The static supports default to vertical Y restraints. The first restraint also has an X direction restraint to prevent the beams moving in the X direction. Z direction restraints are also provided to prevent the beams moving in the Z direction, into the screen. The extreme end restraints can be changed to fully fixed or set as cantilevers by ticking the appropriate boxes.

Alternate loading can also be easily set up if required.

In the continuous beam starter frame, you can change the section type and size and the beam length and loading applied as set out in the MasterFrame manual in the Properties > Member Sections and Materials section and the Loads > Member Loading section.

 

 

Sub-Frame

 

 

The Sub-Frame can be set up in a similar way to the continuous beam. The main difference is that the columns can be placed above and below the beams to provide frame stiffness. Any end moments in the beams will partially redistribute to the columns in relation to their individual stiffnesses.

In the starter sub-frame, you can change the section type and sizes and the beam length and loading applied, etc, as set out in the MasterFrame manual in the Properties > Member Sections and Materials section and the Loads > Member Loading section.

 

 

Multi-Storey Frame

 

 

The Multi-Storey Frame basic data can also be set up in a similar way to the continuous beam. The main difference is that a number of storeys can be added to the frame. Any end moments in the beams will partially redistribute to the columns in relation to their individual stiffnesses.

In the multi-storey frame you can change the section types and sizes and the beam length/column heights and loading applied as set out in the MasterFrame manual in the Properties > Member Sections and Materials section and the Loads > Member Loading section. Member end releases and base restraints can also be added or modified.

The positions of the beams and columns can be easily moved and additional members added where required. The frame can be copied in the 3rd dimension to make a full 3D structure on to which area loading, etc can be added – see chapter on 'Creating a Model'.

Most 3D frames will start out using either the Floor Plan or the Multi-Storey Frame as their starter frame.

You can also set the multi-storey frame as a grillage of beams in the horizontal plane rather than as a frame in the vertical plane.

 

 

Multi-Bay Portal Frame

 

 

In the Multi-Bay Portal Frame basic data, a single or multi-bay plane portal frame is initially set up. This plane portal frame can later be developed into the 3rd direction to create a full 3 dimensional frame which can be loaded with gravity loads and wind loads.

 

The number of bays across the plane portal frame can be entered and the default span in metres. All the bays will default to this span unless you untick the ‘Equal Bays (Spans)’ box. Unticking the box will open up a droplist containing each of the spans. Move to the appropriate span number and alter its data individually.

The height to eaves and the additional rise to the apex should be entered. Note that these are to the centrelines of member sections for the columns and rafters. If there is to be an eaves haunch, the haunch depth (from the intersection of the column/rafter to the bottom of the haunch where it touches the column flange) and length (on the slope from the centreline of column/rafter intersection to where the haunch touches the rafter bottom flange) are added.

 

An apex haunch length can also be added (slope dimension from centreline to rafter bottom flange). Enter the spacing between the frames in the 3rd dimension. This is used to calculate the UDL member loads for the Dead and Live loads which are entered as area loads in kN/m2 in plan.

Suggested section sizes for the rafters, external and internal columns are entered along with the base fixity. 0% represents a pinned base and 100% a fixed base. Should you wish to make use of some base fixity for sway and service load combinations, please see section on partial fixity.

If you click on the wording ‘Rafter Section’, ‘External Column’ or ‘Internal Column’ a Steel Sections dialog box will open in which you can select the section type, grade and size for each.

The frame can be added to and manipulated using the functions along the top menu – see the MasterFrame manual for further details.

 

 

Tower Frame

You can develop several types of towers and trusses in the Tower Frame starter frame option. These include N, V and Vierendeel trusses and X, V, Vierendeel and Pi shaped towers. We will initially look at the 3 truss types and their basic input data.

 

N, V and Vierendeel Trusses

 

Having selected the Tower Frame, you can drop the list of trusses/towers and pick from the N or V type lattice or the Vierendeel truss.

 

The input for each is essentially the same.

 

Enter the number of panels to the left of the middle of the truss. These will be mirrored about the truss centreline. Enter the overall span, the height at the supports and the centre and any camber height at the centre.

In the example below the centre height is greater than the support height.

In the next example the support and centre heights are the same but the centre camber has been set to 1m so as to raise the centre of the truss.

 

For the truss you can release the internal members and ensure frame symmetry.

The truss can also be set up as a space triangular shaped truss. On choosing this option you will also be asked to enter the truss depth into the 3rd dimension.

 

You can also choose to have all the panels equally spaced in the horizontal direction, or allow the program to auto space the panels depending on the shape of the truss.

The truss can also be ‘Positioned between two nodes’. This is useful if you are adding a truss to an existing model and wish to place it between 2 specific node points in the model. You will be asked for the 2 specific node numbers.

 

X, V, Vierendeel and Pi Towers

 

 

The data to be entered for the towers is very similar to that for the trusses above.

For the PI towers the Ratio for PI is the ratio for the distance the diagonal member is across the horizontal member. For example, in the frame below right, the ratio is 0.333. In the second example, the Vertical Ratio is the ratio up the leg that the diagonal starts at, 0.5 in this case.

 

 

              

 

 

Roof Truss

The space roof truss – enter the number of panels in the X and Z directions and the panel lengths. Enter the vertical height of the truss. The truss can be inverted if required.

 

 

Fink Truss

The Fink truss can be set up easily by entering the span and max height of the truss. Usually, you would also release the internals so they only take axial loads. The truss can also be placed in an existing frame between 2 specified nodes.

 

 

 

N & V Lattice Trusses

These have both been covered under the Tower Frame above.

 

 

Library

There is a library of frames in a Library directory containing different shaped trusses and other starter frames for the user to choose from as the basis of a structure.