3DFrameCalc TW

Generate a straight series

Enter the first node and its X/Y/Z coordinates. Use No. of Inc for the number of additional nodes, Node Inc for the node-number step, and X-inc / Y-inc / Z-inc for the coordinate steps in metres.

Enter Y in End / Inc to treat the three increment cells as the final coordinates instead. The generated nodes are spaced evenly up to that endpoint.

Copy a block — B

B1 copies the generated block starting at node 1. B1-5 copies all nodes produced by input lines 1 to 5, including nodes generated within those lines. The current row supplies the coordinate increments for each copy.

Leave Node Inc blank to number copies after the highest existing node. Enter a value to apply a specific node-number offset per copy.

Move a block — M

M1-4 moves the existing nodes generated by input lines 1 to 4 by the offsets entered in X-inc, Y-inc and Z-inc. Leave No. of Inc, Node Inc and End / Inc blank. Each node moves once, even if it appears on more than one referenced line; deleted nodes are skipped.

Generate a polar array — R

R1 rotates the nodes produced by input line 1. R1-4 rotates the nodes produced by lines 1 to 4. The R row's X/Y/Z coordinates define the rotation centre. No. of Inc is the number of additional copies.

For an R row, X-inc / Y-inc / Z-inc are angles in degrees about the corresponding global axis. For example, Y-inc = 45 with No. of Inc = 7 creates seven copies around the vertical Y axis.

Node Inc is the node-number offset per copy. For source nodes 1–4, an offset of 4 creates nodes 5–8, then 9–12, and so on. Choose an offset that avoids existing node numbers, or leave it blank for automatic numbering.

Enter Global in an R row's End / Inc cell to generate coordinates while retaining standard member-section and global support directions. Condense uses this setting for recognised rotational copies.

Condense imported definitions

After a DXF import, a Condense preview opens automatically when shorter definitions are available. Choose Nodes, Members or both, then Apply. Straight sequences, translated blocks and single-axis rotational blocks are recognised; irregular nodes remain explicit. Node numbers and member order are retained. Coordinates are checked within 0.000001 m. Undo restores the previous tables.

Automatic radial section alignment

Members joining consecutive nodes in the R source chain, and the matching segments in each rotated copy, automatically align their section depth (local Y) with the radius from the rotation axis. Beta adds a rotation to this alignment.

For a source chain 1-2-3-4, members 1–2, 2–3 and 3–4 and their rotated copies qualify. A connection between copies, such as 30–2, keeps the standard Beta orientation.

Automatic alignment requires a single rotation axis and a radial direction across the member. Compound rotations, conflicting R axes and members with no transverse radial direction keep the standard Beta orientation.

Delete or paste nodes

To remove a sequence, enter its first node, No. of Inc and Node Inc, then enter Delete in End / Inc. You can also paste a rectangular block of cells from Excel into the node grid.

Define a node chain

1-2-3 creates members 1→2 and 2→3. Shorthand 1-2--6 expands to 1-2-3-4-5-6. Add a final node to close a chain: 1-5--29-1 expands through 1, 5, 9 … 29 and adds member 29→1.

Copy members

No. of extra and Node increment repeat the chain with an offset to every node number. B1-12 copies every member produced by member input lines 1 to 12. For example, No. of extra = 2 and Node increment = 20 produces copies at +20 and +40.

The DXF import Condense preview recognises chains and repeated member blocks. It preserves member order, section references, Beta, releases and active settings. Existing generators are left as entered.

Rigid links

Enter Rigid in the Section column for a weightless link with axial, bending and torsional stiffness set to 10 times the strongest defined member section. This is a very stiff frame member, so its end releases still apply.

Automatic radial alignment and Beta

A member joining consecutive nodes in an R generator's source chain, or the corresponding pair in any angular copy, automatically aligns its section depth (local Y) radially with that generator's axis. Beta is an additional rotation about the member.

For source chain 1-2-3-4, segments 1–2, 2–3 and 3–4 and their copies qualify. Connections between copies, such as 30–2, retain the standard Beta orientation. Click a member to see its alignment source in the status bar, or inspect its section in Properties.

Single-axis R commands about X, Y or Z are supported. If there is no unique rotation axis or transverse radial direction, the member keeps the standard Beta orientation.

End releases and Group

Releases normally apply to every segment. Entering P at both ends of 8-5-2 therefore pins both adjoining ends at node 5. Enter Y in Group to release only the two outside ends of the whole chain.

Use yz for a beam-style pin (releases My and Mz), or xyz to release torsion as well. P, PIN, PINN and PINNED are aliases for yz. Translational releases use codes such as UX, UY and UZ.

Axial-only members

Enter C for compression-only struts or T for tension-only ties. They are drawn as red/blue dashed members; inactive one-way members are grey dotted.

C and T members resist axial force only. They have no bending, shear or torsional stiffness. Member loads, including self-weight, are transferred to the two end nodes as equivalent joint forces, whether the member is active or inactive. This is a joint-load approximation; use ordinary frame members where bending from a load along the span matters.

Active

Leave blank to include a member row, or enter X to exclude it and all its generated copies. A node used only by excluded members, and supports at that node, are also excluded. This is separate from an inactive compression-only or tension-only member in an analysis result.

Copy and paste

Click-drag to select a rectangular range and press Ctrl+C to copy. Paste a rectangular block from Excel starting at the selected cell.

Fixity

Leave Active blank to include a support row, or enter X to exclude it and all its generated copies. A support on a node still used by permanent members must be switched off here explicitly.

Uppercase letters restrain translation (X, Y, Z); lowercase letters restrain rotation (x, y, z). XYZ = pin, XYZxyz = fixed, Y = vertical roller, and YZ = roller free in X. At nodes created by an R row, the support axes follow that radial generator: X is radial, Y follows the rotation axis, and Z is tangential. At other nodes, they are the global axes.

Spring supports

Enter a numerical stiffness in any X/Y/Z/x/y/z spring cell to make that direction an elastic spring support. The same radial axes apply at R-generated nodes. Leave Fixity blank for a row containing only springs.

Gap / one-way restraint

Leave blank for restraint in both directions. For Y, enter + for bearing/downforce-only support (no reaction in the negative direction), or − for uplift/hold-down-only support. X/Z use the same sign convention in their support axes, including the radial axes at R-generated nodes.

Generate supports

Node accepts a single number, list, range or B-row reference such as B1-3. Use No. extra and Node inc. to repeat supports: node = 1, No. = 4, Inc. = 5 creates supports at 1, 6, 11, 16 and 21.

Stage structures

Mark optional members X in the Members table. In Stages, enter X against the load cases and combinations where those members are absent. Blank keeps all members. Both ULS and SLS use the chosen structure; the factors in Loadings are unchanged.

Analysis stops if a combination contains cases with different structure settings, or its setting differs from those cases. Support rows marked X remain excluded in every stage.