Technical information for Users of PrecisionPlus


  • RealDWG is an Autodesk product, the makers of AutoCAD, and is actually used in other Autodesk products such as Autodesk?s Inventor 3D MCAD.
  • Compatibility between AutoCAD and drawings generated using RealDWG is always assured.
  • For future editions of AutoCAD, RealDWG will be updated in parallel to AutoCAD to handle any file format changes or new features.
  • Fully compatible drawing files of R14, 2000, 2004/2005/2006, or 2007 format can be generated using RealDWG (this will be a user-selectable option in PrecisionPlus).
  • PrecisionPlus? implementation of RealDWG allows users to define template drawings containing their own layers, line types, dimension styles, and text styles that will be used when generating new drawings.
  • Drawings generated using RealDWG may be modified in AutoCAD as desired just like any other drawing created in AutoCAD directly.

RealDWG was implemented into PrecisionPlus as part of a version release 8.8.1 in 2007.

SUBJECT: Hardware recommendations for the current version of PrecisionPlus

Processor: 1.5 GHz Pentium or better
RAM: 1 Gig
Video Card: AGP
Printer: HP Deskjet or Laser
Plotter: 11 X 17 or 24 X 36 (D size) for printing plots
Operating System:
Windows 2000 (service pack 3)
Windows Server 2003
Windows XP (service pack 1 or greater)
Windows 7 and Vista (32-bit and 64-bit)

The hard drive should be large enough to handle current usage plus AutoCad or AutoCad LT, PrecisionPlus (approximately 300MB), structure files you may wish to store, and have at least 400 MB of free space to accommodate operation of applications.

Printers and plotters must have Windows drivers. A physical parallel printer port (LPT) or USB port is required, depending on the type of sentinel (hardware lock).

The plotting modules of the program generate drawings as DWG form, compatible with AutoCad LT (98 and newer) and full AutoCad (R14 and newer.)

SUBJECT: Hardware requirements for the current version of PresentationPlus 3D

Processor: 1.5 GHz Pentium or better
RAM: 1 Gig
Monitor: High resolution
Video card: must support 16 bit graphics or better
Microsoft DirectX must be installed.
Operating System:
Windows XP (service pack 2 recommended)
Windows 98
Windows Me
Windows 2000 (service pack 3 or greater)
Note: Windows 95, NT and Vista are not supported

SUBJECT: Frame Design Program

The frame design program provides the user with an effective tool for selecting member sizes for determinate and indeterminate frames of structures.

INPUT There are numerous input options. In the most general form, the user has complete control over the geometry of the frame and most code-dependent factors such as applied loads, load combinations, wind coefficients and bending coefficients.

FORCE DETERMINATION Stiffness factors for all prismatic sections are evaluated using closed form integrals. Tapered members are solved using numeric integration techniques. All tapered members are broken into segments at all points of discontinuity. Each of these segments is evaluated using a thirteen-point numeric integration procedure. Equations are solved using the Gauss Elimination Method. For all indeterminate structures, interaction between member sizes and member forces is accounted for by cycling between the design routines and the force routines until convergence is reached.

MEMBER DESIGN Points are placed to ensure that all critical points will be checked. Forces at each analysis point is determined from the end forces using statics.

The user has an option of either a design or analysis mode. In the analysis mode, member sizes are specified by the user. In the design mode, members are selected from the user's inventories. For built-up members, the inventory consists of the user's individual flange and web sizes. For mill circular members and mill M and W shapes, the inventory of available sections is in user-controlled files.

Effective length factors for major axis buckling of tapered members are modified linearly by the tapered factor for the member.

OUTPUT Output is in a tabular form that is clearly labeled. Sufficient information is included to permit hand checking of stress levels at all stress check points. Output includes:

1) stress analysis
2) geometric properties
3) properties for stress analysis
4) member forces

1) structure geometry
2) forces acting on supports (reactions)
3) external member loads
4) end translations (deflections)
5) member and total weights

SUBJECT: Flange braces on the mainframe cross section plot

Review the related drawings in the Plotting Manual. You may modify these drawings using AutoCad or AutoCad LT to create drawings reflecting your own product line.

The flange brace attachment (bolted or welded clip) is specified in the GFUSER02 setup. The location of the flange brace holes in the purlins or girts is specified in the DRFT46.INP file, as well as the hole locations setup.

If your purlins and girts contain more than one hole location for attaching flange braces (which you will denote by specifying up to three different FBH values), the program will select a hole location which places a flange brace at 45 degrees, or as close to that as possible. If only one hole location is available, you should specify that location for all FBH values.

The notation NS and FS denote Near Side and Far Side, indicating if a flange brace is to be placed on one or both sides of the web at a specified location. The placement of flange braces on one or both sides depends on the member depth at that location. You specify in file DRFT46.INP the maximum depth for placing a flange brace at one side only. If the member depth exceeds this value, flange braces will be indicated NS and FS, for both near and far side placement.

The bolts (and clip, if one is used), as well as the flange brace material, are all specified in file DRFT46.INP. The clip part number must match the first 3 digits of the part number in your clip inventory. If you do not wish to use a clip, the part number 000 should be entered in the DRFT46.INP file. The bolt part number must match the first 3 digits of the part number in your hardware inventory. The flange brace record number is a record number in your c-section inventory.

The location of the girt and purlin flange brace attachment (relative to the web of the girt or purlin) is specified in the GFUSER01 setup.

SUBJECT: Sample Insulation Calculation

The following is a calculation showing how the program determines the square footage of insulation. For this sample, we used a 38x32x14 building with a 1/12 slope.

Roof Insulation: Roof area = WIDTH x AMP x LENGTH x 1.05 / 144
where WIDTH = building width in inches
AMP = roof slope length amplification factor
LENGTH = building length in inches
1.05/144 (= 0.00729166) adds overage and converts to square feet.
Ex. Roof area
= 456 x 1.003466 x 384 x .00729166
= 1281 sq. feet

Endwall Insulation: Height at Peak (HPK) = SWL + WIDTH / 24 x SLOPEL
where SWL = left sidewall height in inches
WIDTH = building width in inches
SLOPEL = roof slope
Ex. Height at peak
= 168 + 456 / 24 x 1
= 187

Endwall area = WIDTH x (SWL + HPK) x .5 x ..00729166
where WIDTH = building width in inches
SWL = left sidewall height in inches
HPK = Height at Peak
Ex. Endwall area
= 456 x (168 + 187) x .5 x ..00729166
= 590

Sidewall Insulation: Sidewall area = SWL x LENGTH x .00729166
where SWL = left sidewall height in inches
LENGTH = building length in inches
Ex. Sidewall area
= 168 x 384 x ..00729166
= 470

Total insulation for building: Total = Roof area + (2 x Endwall area) + (2 x Sidewall area)
Ex. Total for
= 1281 + (2 x 590) + (2 x 470)
= 3401

SUBJECT: Brace Points

When determining the Laterally Braced Capacities for Z-sections, the inflection point is used as a brace point. The inflection points and associated Ly values are reported in the capacities tables. The following illustrates a case where the number of brace locations is 3. Arrows on the sketches indicate the locations of braces. The reference line for the moment curve is the bottom of the section. Ly is equal to SPAN divided by the number of brace locations (# Brace Locs). The lateral support distances for each region are computed as shown.



SUBJECT: Full versus reduced stiffness option


The above drawing shows the full (dashed line) versus reduced (solid line) stiffness moment curves for purlins (or girts).

Full stiffness considers the extra material at the lap area when calculating internal forces including moments. More moment at the support may result in a longer lap. Less moment at midspan may result in lighter sections. The reduced option ignores the extra material in the lap for forces. This sometimes results in heavier sections.

The LGSI (Light Gage Structural Institute) uses the full stiffness option in the 1998 publication. The 1992 publication was based on reduced stiffness.

Possible result summary table:

Stiffness option Section Lap
Full Smaller Longer
Reduced Larger Shorter

SUBJECT: Endwall Design Report (DESNEW01)

The DESNEW01 report provides properties used in endwall rafter design and endwall reactions. The following is a list of values that are output and a reference or description for each. For reactions, positive is down and toward the center of the building.

DESNEW01 report (rafters)

SUPPORT NUMBER Joint number for which reaction is reported. Joint numbers is 1 at left sidewall, 2 at midspan between left sidewall and adjacent endwall column, 3 at endwall column, etc.

LOAD DESCRIPTION Load combinations, as specified in the building code, or as modified at run time on the Load Combinations screen.

VERTICAL Reaction at the specified support number (KIPS). These reactions correlate to the vertical reactions at the base of the endwall columns.

SUBJECT: Design of Endwall Report (DESNEW03)

The DESNEW03 report provides information about endwall column reactions, endwall column design and properties used in endwall column design.

DESNEW03 report

ENDWALL COLUMN DATA FOR COLUMN # Identification of endwall and column. Column number is the interior endwall column identification numbering from left to right sidewall.

LOAD NUMBER # WIND CASE NUMBER # This identifies the load number and wind case number. The values for load number correspond to values under the heading LD in the General Geometry report.

BASE REACTIONS HORIZ VERT These are horizontal and vertical base reactions for the current column and endwall. Vertical is positive down, horizontal is positive toward the center of the building. (KIP/FT)

LOAD LOCATIONS Loads to the endwall columns are applied as concentrated loads at all girt locations. (FT)

LOAD MAGNITUDES Load values are included for each girt location. (KIP/FT)

The base reactions, load locations and load magnitudes are repeated for each load combination and wind case.