MStower V6
User’s Manual
Engineering Systems
COPYRIGHT NOTICE
(C) Copyright Engineering Systems Pty Limited 1997-2008. All rights are reserved. The copyright applies to this manual and to the corresponding software (together referred to herein as the “licensed material”).
DISCLAIMER
Subject to limitations imposed by law, Engineering Systems Pty Limited makes no warranty of any kind in connection with the licensed material. Engineering Systems Pty Limited shall not be liable for any errors contained in the licensed material nor for any incidental or consequential damages resulting from the use of the licensed material. Engineering Systems Pty Limited is not engaging in the provision of consulting services in supplying the licensed material. Users of the licensed material are advised that output from computer software should be subjected to independent checks. Engineering Systems Pty Limited reserves the right to revise and otherwise change the licensed material from time to time without notification, or provision of revised material.
SOFTWARE LICENCE
The software is supplied to the user under licence. It may be installed on as many computers as required but the number of concurrent users must not exceed the number of licences held. For network licences, use is permitted only in the country for which the licence was supplied. The software may not be sub-licensed, rented, or leased to another party. The licence can only be transferred to another party at the discretion of Engineering Systems Pty Limited.
Engineering Systems Pty Limited 14 Eastern Road
PO Box 85
Turramurra NSW 2074 Australia
Tel: +612 9488 9622 Fax: +612 9488 7883
E-mail: [email protected] Web: www.mstower.com.au
April, 2008
Crystal Palace Tower, London
This is Britain’s tallest unguyed steel tower. It was checked for structural adequacy using MStower.
Preface
MStower is a software package for the analysis and design of towers, masts, and poles. This software incorporates the very latest in Windows technology to make it easier to use and improve your productivity.
“1:Introduction” provides an overview of the capabilities of MStower. Whether you are installing MStower for the first time or updating an existing system, you will find all the necessary information in “2:Getting Started”. “3:Menus & Toolbars” provides a summary of the commands available and other chapters provide reference and technical information.
This manual is available to the MStower user on-line, together with “pop-up” help for toolbar buttons and dialog boxes. The on-line Help system provides a synchronized table of contents and powerful methods of searching for topics.
If the file Readme.txt is present in the MStower program folder after installation, you should read it for information that became available after the manual was printed. The file is automatically displayed during installation but it may be displayed in Notepad at any time by double-clicking the file in Windows Explorer.
MSTowerV6 Contents• i
Contents
1:Introduction 1
General... 1
Responsibility ... 4
Acknowledgement ... 5
Enhancement Record ... 5
2:Getting Started 9
Installing MStower ... 9Hardware Lock ... 9
Folders ... 10
Starting MStower... 11
Commands ... 12
Right-Clicking Away from Any Part of the Tower ... 12
How to Make a Shortcut on the Desktop... 13
Launch with Double-Click... 13
Configuration... 14
Printing in MStower ... 15
Print and Print Preview Commands... 15
The Windows Print Dialog Box ... 15
The Page Setup Dialog Box ... 16
Configurable User Graphic... 18
Steel Section Libraries ... 18
Data from Earlier Versions ... 19
Technical Support ... 19
Web Update ... 20
3:Menus & Toolbars 21
Layout... 21File Menu Commands... 22
View Menu Commands ... 23
Tower Menu Commands ... 24
Member Checking Menu Commands ... 24
Structure Menu Commands ... 25
Analyse Menu Commands... 26
Results Menu Commands ... 27
Reports Menu Commands ... 27
Show Menu Commands... 28
ii• Contents MSTowerV6
Query Menu Commands ... 29
Window Menu Commands...30
Help Menu Commands...31
Main Toolbar Commands...31
View Toolbar Commands ... 32
Display Toolbar Commands...33
Help Toolbar Commands ... 33
Draw Toolbar Commands ... 34
Attributes Toolbar Commands ...34
Results Toolbar Commands ...35
OK/Cancel Toolbar Commands ...35
Extra Buttons Toolbar Commands...36
Selecting Which Toolbars Are Displayed...36
Customizing Toolbars ... 37
The Ouput Window...37
4:Operation 39
Data Files ... 39Units...40
Coordinate Systems ...40
Sections...41
Member Checking...41
Export to Microstran Archive File...41
Errors...41
5:Tower Data 43
General...43The Tower Data (TD) File ... 44
Title Block ... 45
Component Block ... 45
Profile Block ... 46
Supports Block...53
Guys Block ...54
Sections Block ... 55
Material Block ... 58
Bolt Data Block ... 58
Guy Library...61
Steel Poles ... 62
TD File Examples ... 65
Example 1 ... 65
Example 2 ... 66
Example 3 ... 67
Example 4 ... 68
Example 5 (Plan Bracing)...70
6:Standard Panels 71
General...71MSTowerV6 Contents• iii
Index – Face Panels ... 72
Index – Plan Bracing ... 76
Index – Hip Bracing & Cross-Arms ... 77
D & V Face Panels ... 78
X Face Panels ... 79
K Face Panels ... 84
M Face Panels... 94
W Face Panels... 96
XMA Face Panel... 98
XDMA Face Panel... 99
DM, DM2 Face Panel ... 100
DMH, DMH2 Face Panel ... 101
DLM, DLM2 Face Panel ... 102
KXM, KXM2 Face Panel ... 103
SH3, SH4 ... 104
Plan Bracing ... 105
Hip Bracing... 112
Cross-Arms... 115
7:User-Defined Panels 117
General... 117The UDP File... 118
Making A UDP Using Graphics Input... 122
UDPs for Poles ... 122
Modifying An Existing UDP ... 123
Towers With Unequal Length Legs... 123
Creating a UDP from a Microstran Job ... 124
UDP File Names... 125
8:Graphics Input for UDPs 127
General... 127Basic Drawing ... 128
The Drawing Snap Mode... 130
The Drawing Plane ... 131
Automatic Removal of Duplicate Nodes and Members ... 131
Cursors... 132
Shortcut Keys ... 133
Selecting Nodes and Members ... 133
Right-Clicking on Nodes and Members ... 134
The Node Properties Dialog Box... 135
The Member Properties Dialog Box ... 135
Properties Dialog Boxes with Multiple Selection... 136
Extrusion... 136
Interrupting Commands ... 136
The Stretch Command ... 137
The Limit Command... 138
Removing an Intermediate Node ... 139
UDP Graphical Example ... 140
iv• Contents MSTowerV6
Step 1 – Create Data File for a Small Tower ... 140
Step 2 – Build Tower ... 142
Step 3 – Isolate UDP Members...142
Step 4 – Add Members to UDP ...143
Step 5 – Define Attributes of New Members...144
Step 6 – Copy New Members to Other Faces ... 144
Step 7 – Set Reference Nodes for New Members...145
Step 8 – Check UDP ...145
Step 9 – Convert Graphics to UDP File... 145
9:Tower Loading 147
General...147The Tower Loading (TWR) File ...148
Parameters Block ... 148
Damping ... 152
Basic Velocity...152
Terrain Block ... 153
Velocity Profile Block ...159
Named Node Block... 160
Guy List Block...161
External Factor Block ...162
Loads Block ... 162
Wind Load Cases ... 163
Cross-arms and Similar Members External to the Main Tower Body ...165
Guyed Mast Patch Loadings ...165
Dead Loads ... 166
Ice Loads...166
Miscellaneous Loads...167
Additional Node Loads ... 167
Additional Member Temperatures ...167
Eathquake Load Cases ...168
Combination Load Cases ...170
Panel Block...170
Ancillary Block...171
Output...178
Computation of Wind Resistance...179
BS 8100 ... 179
AS 3995 ... 180
AS 1170 ... 180
Malaysian Electricity Supply Regulations 1990... 180
EIA/TIA-222-F ...181
TIA-222-G ... 181
Computation of Deflections ...182
BS 8100 ... 182
Other Codes ... 182
Dynamic Amplification of Wind Loads...183
BS 8100 ... 183
AS 3995 ... 183
AS 1170 ... 184
MSTowerV6 Contents• v
EIA-222-F ... 184
TIA-222-G... 184
ASCE 7... 184
IS 875 ... 185
BNBC ... 185
ILE TR7... 185
Ancillary Libraries... 186
Large Ancillary Library... 186
Linear Ancillary Library... 188
Drag Coefficients ... 189
10:CAD Interface 191
General... 191Exporting a CAD DXF ... 191
Exporting a Steel Detailing Neutral File... 192
Section Alias File... 193
Windows Clipboard Operations... 193
11:Analysis 195
General... 195Method ... 196
Consistency Check ... 196
Accuracy... 196
Linear Elastic Analysis ... 197
Non-Linear Analysis... 197
Second-Order Effects ... 198
Running a Non-Linear Analysis ... 200
Troubleshooting Non-Linear Analysis ... 203
Elastic Critical Load Analysis ... 204
Selecting Load Cases for ECL Analysis... 205
Analysis Control Parameters ... 205
Why ECL Analysis May Give High k Factors ... 206
Dynamic Analysis... 207
Analysis Control Parameters ... 207
Dynamic Modes ... 208
Response Spectrum Analysis... 209
Defining Load Cases ... 209
Running a Response Spectrum Analysis ... 209
Response Spectrum Curves ... 212
Errors ... 213
12:Member Checking 215
General... 215Operation ... 216
Loading Parameters ... 216
BS 8100 Part 3... 216
BS 449 ... 216
vi• Contents MSTowerV6
ASCE 10-90, ASCE 10-97, ASCE Manual 72 ... 217
EIA-222-F...217
TIA-222-G ... 217
AS 3995 ... 217
IS 802...217
ILE TR7 ... 217
BS 5950 ...218
AS 4100 ... 218
Design Loads...218
Member Checks to BS 8100 Part 3 ...219
Member Checks to BS 449...220
Member Checks to AS 3995 ... 221
Member Checks to ASCE 10-90 1991 & ASCE 10-97 1991...222
Member Checks to EIA-222-F 1998...223
Member Checks to TIA-222-G 2005 ...225
Member Checks to IS 802...226
Member Checking to ILE Technical Report 7 ...226
Member Checking to BS 5950...227
Member Checking to AS 4100...227
Member Checking to ASCE Manual 72...227
Obtaining Design Results...228
Steel Detailing...228
Editing Ancillary & Guy Libraries...228
13:Editing the Section Library 229
General...229Section Library...229
Section Library Manager...233
Compiling a Library...236
Editing a Library with a Text Editor ...236
Library Viewer...237
14:Reports 239
Report Types ... 239Display and Printing of Files...240
Input/Analysis Report ... 240
Error Report ...241
Static Log ... 241
Dynamic Log...241
Design Summary...241
Detailed Design Report ... 242
Reaction Report...242
Rotation Report ... 242
15:Examples 243
General...243TWEX1 ...246
MSTowerV6 Contents• vii
15:Ancillary Programs 253
CTIDATA... 253
Index 255
MSTowerV6 1:Introduction• 1
1:Introduction
General
MStower is a specialized program that assists in the analysis and checking of latticed steel communication and power transmission towers and guyed masts and steel monopoles.MStower contains options for defining the geometry, loading, analysis, plotting of input, results, and member checking.
Loading may be computed in accordance with:
• BS 8100 Part 1 1986
• BS 8100 Part 4 1995
• AS 3995-1994
• AS/NZS 1170.2:2002
• Malaysian Electricity Supply Regulations 1990
• EIA/TIA-222-F-1996.
• TIA-222-G-2005.
• Institution of Lighting Engineers Technical Report No. 7 – High Masts for Lighting and CCTV – 2000 Edition.
• IS 875 (Part 3):1987
• BNBC 93 – Bangladesh National Building Code
• ANSI/ASCE 7-95
• NSCP C101-01 – Philippines National Building Code
Member capacities may be checked against the requirements of:
• BS 8100 Part 3
• BS 449
• AS 3995-1994
• ASCE 10-90, ASCE 10-97
• EIA/TIA-222-F-1996
• TIA-222-G-2005.
2• 1:Introduction MSTowerV6
• Institution of Lighting Engineers Technical Report No. 7 – High Masts for Lighting and CCTV – 2000 Edition.
• BS 5950-1:2000 (for tubular poles)
• IS 802 (Part 1 / Sec. 2):1992
Towers, which may be of three or four sides or a single cantilevered tubular pole, are assembled by combining a series of standard face, plan, hip, and cross-arm panels. The tower profile is defined by giving the height of individual panels and the width at “bend” points. All other widths are obtained by interpolation. The range of standard panels is being regularly increased with over 100 different panel types available at present. A number of the standard panels are parameterised so that the
user may readily modify the configuration.
If a suitable standard panel is not available the system accepts “user- defined panels” (UDP). While these require much more data than a standard panel, they allow the system to be used for virtually any tower configuration. A UDP may consist of anything from a few members that make up half a face panel to a full three-dimensional section of the tower.
The result of the tower building process is a complete MStower data file, Job.mst, where “Job” is the MStower job name.
The loading module of MStower computes loads due to self-weight, ice, and wind on the tower. As well as computing wind loads on the bare tower the program is able to take account of a wide range of ancillary items found on communication towers.
Ancillaries are classified into the following categories:
• Linear ancillaries, normally within the body of the tower and consisting of items such as ladders, feeders and wave-guides.
• Face ancillaries, attached to the face of the tower and consisting of small items such as minor antennae, gusset plates and platforms.
• Large ancillaries, mounted out from the face of the tower and consisting of large dishes whose wind resistance is significant compared with that of the structural members of the tower.
• Resistance.A group of ancillaries may be described by their wind resistance over a height range of the tower.
• Insulators, located between the segments of multi-segment guys.
Ancillary libraries containing data describing the physical and drag characteristics of a wide range of antennae types are provided with MStower. The libraries are plain text files and may be easily added to by users. For a dish antenna the library would typically include its diameter, mass, location of center of gravity, surface area that may be coated with
MSTowerV6 1:Introduction• 3 ice, and its projected area and a drag coefficients for a range of angles of incidence.
Six aerodynamic coefficients are specified for each angle of incidence to enable antenna forces and moments to be computed automatically.
The use of ancillary libraries simplifies the preparation of the data needed to compute the loads on the tower. To fully describe an antenna its library reference, its location on the tower, and its bearing are required. MStower will extract all other data from the library, compute the forces acting on the antenna (dead load, ice-load, and wind loads) and transfer them into the tower as a set of statically equivalent forces.
To assist in checking of input data MStower displays the tower and all linear and large ancillaries. As well as the visual display, any ancillary may be queried by “picking” with the graphics cursor to obtain its identification, location, library reference, and other pertinent data.
The strength of members may be checked against the rules of the codes listed above, with the results available as a summary report giving the critical load case and condition or a larger detailed report suitable for checking the computations for each member. The results of the member check may be shown as a graphical display with the color in which a member is displayed depending on its maximum load/capacity ratio.
Foundation reactions and ancillary rotations may also be reported.
4• 1:Introduction MSTowerV6
Responsibility
MStower is intended to assist designers in performing the necessary calculations for checking and designing towers, guyed masts, and steel monopoles. Users must have an understanding of these structures and a good knowledge of the codes of practice to which they are working.
MStower cannot replace sound and responsible engineering judgement and practice.
The interpretation of the output from MStower and the application of this data is solely the responsibility of the user.
Good engineering practice requires fully triangulated bracing systems in towers. Tower design codes do not check for bending stresses in
members or their bending stiffness, so members in bending should not be used to restrain compression members. Features to check for include:
• Plan bracing must be fully triangulated to provide restraint and maintain the plan shape of the tower.
• Hip bracing must be fully triangulated and connected to the
plan bracing system within a panel to resist twisting of the whole leg/hip bracing assembly.
• Bend points in K brace arrangements must have the knee fully braced in two directions.
• The ends of K brace members must be restrained and coincide with plan bracing members at the top of the panel.
• Leg bend points must be fully braced in two directions.
• Where leg members join in towers with staggered face bracing, restraint should be provided in the unbraced face by plan bracing or a similar system.
MStower is not able to detect automatically the lack of restraint in non- triangulated arrangements. If non-triangulated bracing is used, additional manual checks to the relevant design code must be made to ensure that there is sufficient strength and stiffness to provide adequate restraint to other members.
Designers should consider the safety of any temporary arrangements during construction.
MSTowerV6 1:Introduction• 5
Acknowledgement
Initial development of sections of MStower was done under contracts with the Independent Broadcasting Authority, Eastern Electricity, British Telecom, and the British Broadcasting Corporation.
Particular recognition is due to Mr M J Lambert of the Independent Broadcasting Authority who initiated this work.
Enhancement Record
Version 3.1
New menu introduced.
TWR file format revised.
Terrain blocks introduced.
Linear and large ancillary libraries introduced.
32 bit version of programs introduced.
Additional standard panels introduced.
GUST and MEAN keywords added to TWR file.
Graphical input of UDPs introduced.
Version 3.15
Screen querying of linear ancillary, large ancillary, and ancillary groups introduced with graphical representation of larger ancillaries.
Ancillary libraries extended to include Andrew information.
HP LaserJet printers now supported for plotting.
PostScript format available for output files.
Ancillary deflections and rotations calculated.
Foundation reactions calculated.
CROSS and BARE keywords added.
Total mass and additional mass of ancillaries in TWR file.
XIP, plan bracing at intersection point of face bracing.
Optional Velocity Profile.
Version 4
Masts including catenary cables to BS 8100 Part 4 and AS 3995.
Additional standard panels.
Named node block introduced.
Supports block.
6• 1:Introduction MSTowerV6 Version 4.1
EIA/TIA-222-F-1996.
ASCE 10-90 1991 (Manual 52).
Bolt checking to DD133/BS5950.
Deflections/rotations.
Version 4.15
Manual re-set in Microsoft Word.
Examples revised.
Partial safety factors for materials now applied at member checking stage.
Database utilities added.
Bolt data file included.
Version 4.20
Shade factor introduced for linear and large ancillaries.
Job.out file enhanced for results checking.
Version 4.21
Tension-only members now available in UDPs; non-linear analysis module required.
Version 5
New 32-bit Windows version. Ancillary display improved; split view with ancillary labelling. Database recognition and automatic loading from CSV files. Enhanced metafile export of views. Non-linear analysis convergence parameters added. Smear loading for wind on guys. UDP input completely revised. Support for DOS discontinued.
Generation of TD and TWR files. Multi-segment guys and guy
insulators supported. Asymmetrical ice loading added. Bolt checking to AS 3995, EIA-222, and ASCE 10-90 added.
Version 6
Rectangular towers may be generated directly from standard panels.
Different bracing patterns and sizes may be generated on X and Y faces of four sided towers using standard panels.
Loading to AS/NZS 1170.2:2002, IS 875, BNBC, ASCE 7-95, Philippines NBC.
Earthquake loading.
MSTowerV6 1:Introduction• 7 Greater user control over the manner in which ancillary resistance is used.
Generation, loading, and checking of steel monopoles.
Virtual reality graphics.
Gust response factor calculations for dynamically sensitive towers for some codes.
Member checking to ASCE 10-97, IS 802.
Member checking to BS 8100 Part 4 replaces DD133-1986.
Panels may have one or two sets of plan bracing.
UDP member classes specified directly.
Section Library Manager.
Web downloads.
TIA-222-G-2005 implemented.
8• 1:Introduction MSTowerV6
MSTowerV6 2:GettingStarted• 9
2:Getting Started
Installing MStower
The Setup program will install MStower on your computer. Usually, Setup will begin when you insert the CD. If Setup does not begin automatically you must perform these steps:
• Click on the WindowsStart button and selectRun.
• Browse to theSetup program on the distribution CD.
• Execute theSetup program.
Setup will guide you through the installation process, prompting you for a name for the program folder (the default is C:\Mstower), and then copying the required files to the hard disk. Necessary fonts will be installed.
Hardware Lock
MStower is normally supplied with a USB hardware lock that must be attached to the computer before you can start the program. Additional set-up procedures are required for systems with a network lock. These are described on a separate data sheet.
10• 2:GettingStarted MSTowerV6
Folders
The Setup program will establish a number of folders under the specified MStower folder. If you use the default name the folders as displayed in Windows Explorer will look like this:
MSTOWER FOLDERS
Folder Name Comment
Mstower MStower folder – you can choose this name during installation. “Mstower” is the default.
...Data Default data folder – you can open MStower files in other folders if you wish.
...Examples Example files – useful for testing and learning.
...PDF Contains documentation in PDF format, including full user manual.
...Program All MStower program files, library files, and Help files.
...Service For network version only, this folder contains network support and documentation files.
Library File Folder
You may use theFile > Configure > General > Library File Folder command to specify a folder for library files anywhere on the computer or in the Network Neighborhood. Files in this folder will be accessed when you refer to a library file with the “L:” prefix. Using the “P:”
prefix will cause MStower to look in the Program folder for library files.
Library file references that do not have a prefix cause MStower to look in the data folder for library files.
MSTowerV6 2:GettingStarted• 11 Temporary File Folder
By default, MStower writes intermediate data to the Windows temporary file folder. This is usually most satisfactory for all types of installation.
You may, however, use theFile > Configure > General > Temporary File Folder command to specify a different folder anywhere on the computer or in the Network Neighborhood.
Starting MStower
The Setup program creates an MStower item on the Windows Programs menu (clickStart, thenPrograms). Click on this item to start MStower.
If you have not previously used MStower you should start with some of the examples supplied with MStower to familiarize yourself with the operation of the principal menu and toolbar items (see
Chapter 15:Examples on page 243). To run an example, use theFile >
Open command and click on the required file in the dialog box.
You may open any existing MStower job with theFile > Open command. To start a new job based on an old job, open the old job and save a copy with another name using theFile > Save Copy As command. You may now close the old job and open the new copy by selecting its name from the most recently used list on theFilemenu.
Note the following powerful Help features, which make it easier for you to use MStower:
• There aretooltips on all toolbar buttons. Move the mouse cursor over the button for a moment and a little pop-up window displays the function of the button.
• There is a prompt displayed on the left side of the status bar (at the bottom of the MStower window) whenever the cursor is positioned over a toolbar button or a menu item. Look here for prompts while you are performing input operations.
• Context-sensitive help is available for all toolbar buttons by clicking the button. Once you have clicked this button, move the new cursor to any item and click.
• Context-sensitive (pop-up) help is available in dialog boxes. Some items in dialog boxes also have tooltips.
Use theHelp > MStower Help Topics command to display the Help Topics dialog box. With this, you can browse the table of contents, look through an index, or search all Help topic keywords.
12• 2:GettingStarted MSTowerV6
Commands
MStower commands are available from:
• The main menu.
• Toolbar buttons.
• The context menu.
Generally, all the commands are available on the main menu, while, for convenience, some of them are also available on toolbar buttons or the context menu. Commands selected from the main menu are referred to in this manual as shown in this example:
View > Zoom > Window
Commands selected by clicking a toolbar button are referred to by the name of the button, as shown in the tooltip.
Right-Clicking Away from Any Part of the Tower
When you right-click in the main window, away from any node or member, the pop-up menu below appears.
MAIN CONTEXT MENU
This provides a very convenient alternative to the main menu for many commands. In effect, you can perform some operations in three different ways. For example, you can display the section number on all members by clicking a button on the Display toolbar, by selecting theView >
Display Options command, or by right-clicking and then selecting Section Numbers.
MSTowerV6 2:GettingStarted• 13
How to Make a Shortcut on the Desktop
To make a shortcut to MStower on yourdesktop (the background that is visible when no programs are running), drag the MStower icon from the Start > Programs menu while holding down the Ctrl key.
Launch with Double-Click
MStower job files (Job.mst, where “Job” is the job name) should be identified in Explorer with a distinctive icon. It is convenient to be able to double-click on one of these files in Explorer to start MStower with the job. To do this, the MST file type must be associated with MStower.
The association between MStower and the MST file type may be established when MStower is installed. You may also establish the association with the procedure set out below.
Here are the steps necessary to make MStower launch with a double- click:
• In Explorer select theView > Folder Options orView > Options command.
• Select the File Types tab.
• In the list box search for the MStower job file type, which may be shown as “MST File” or “MStower Document”. If found, select this file type and click the Remove button. Close the dialog box.
• In Explorer browse to the MStower data folder and double-click on any MStower job file (if the file name extension “mst” is not visible you may see it by right-clicking and checking the properties of the file).
• The Open With dialog box appears. Click on the Other button and browse to Mst.exe in the MStower program folder.
• In the Description box type “MStower Job File” and click OK.
• In Explorer select theView > Folder Options orView > Options command.
• Select the File Types tab, then select “MStower Job File” in the list box and click the Edit button.
• Click the Change Icon button and then select the second icon.
• Click OK to close the Edit File Type dialog box.
• Click OK to close the Folder Options dialog box.
Now, check that you have successfully set up your system by browsing to an MStower job file and double-clicking.
14• 2:GettingStarted MSTowerV6
Configuration
The first time you start MStower it will run in a partial screen window.
Maximize the Window (use the button next to theX button at the top right of the MStower window) and the system will thereafter start in a full- screen window.
Toolbars may be activated or de-activated using theView > Toolbars command and they may also be floated or moved to different locations on the main window if desired (“docked”). Toolbar buttons may be dragged from one toolbar to another while theAlt key is held down.
Chapter 3 contains more information on how you can customize the toolbars.
TheFile > Configurecommand allows you to set program parameters such as colors, default library files and design codes, and maximum job size. The default settings for maximum job size will be sufficient for the majority of jobs. Increasing limits unnecessarily can result in slightly reduced operating speed.
FILE > CONFIGURE
MSTowerV6 2:GettingStarted• 15
Printing in MStower
Print and Print Preview Commands
MStower differs from many standard Windows application in that there is a requirement to print both files (reports) and pictures. As in a standard Windows application, MStower has a Print command on the File menu (File > Print File). This is for printing files and reports. Also, there is a Print command on the View menu (View > Print View) and this is used for printing pictures of the structure. The File menu is shown in “File Menu Commands” on page 22 and the View menu is shown in “ View Menu Commands” on page 23.
In addition to Print commands on the File and View menus, MStower has Print Preview commands on each of these menus. The print preview shows an exact image on the screen of the printed page.File > Print Preview shows you how a report will be printed whileView > Print Preview is for MStower graphics.
The main toolbar, usually located right under the menu, contains a Print
button, , and a Preview button, . These buttons are for MStower
graphics, not files or reports. Thus, they correspond to the Print and Preview commands on the View menu – notice that the tooltip for the Print button is “Print View”. The main toolbar is shown in “Main Toolbar Commands” on page 31.
The Windows Print Dialog Box
While the Preview button acts exactly the same way as the
corresponding menu command, the Print button does not. TheView >
Print View command displays the Windows Print dialog box so you can change the target printer, the number of copies, or printer settings with the Properties button.When you click OK in this dialog box the selected printer becomes the current printer. TheFile > Print File command also displays the Windows Print dialog box before printing. Clicking the print button on the main toolbar, however, initiates a graphics printwithout
the display of the Windows Print dialog box. The view is printed immediately to the current printer.
WINDOWS PRINT DIALOG BOX
16• 2:GettingStarted MSTowerV6 Preview commands,File > Print Preview,View > Print Preview, and the Preview button, all do not display the Windows Print dialog box.The preview is always for the current printer. When you see a print preview
on the screen, you will notice a Print button at the top left of the preview window. Clicking this will initiate printing on the current printer. If you want to change the target printer after seeing a preview, close the preview window and then select the Print command on either the File or
the View menu. When previewing a multi-page report file, the Print button prints the whole file. If you want to print less than the full report
use theFile > Print File command and select the pages to be printed in the Windows Print dialog box.
The Page Setup Dialog Box
The Page Setup dialog box allows you to change settings affecting the layout of printed output, either graphical or reports.
The current printer, shown in the Page Setup dialog box, is initially the Windows default printer and remains so until a different printer is selected. A new current printer may be selected in the Windows Print Setup dialog box that is shown when you click the Change button. You may also change the current printer in the Windows Print dialog box shown when you select eitherView > Print View orFile > Print File.
MSTOWER PAGE SETUP DIALOG BOX
Text Size
The text size, in points, for both reports and graphical output. There are 72 points to the inch. The default value is 8.
MSTowerV6 2:GettingStarted• 17 Orientation
Mstower does not use the orientation setting stored with the printer properties. These two settings, one for reports and one for graphics, are
used instead.
Margins
Margins may be set independently for reports and graphics.
Logo
Check this box if you want MStower to print a logo at the top of each page of printed output. When the box is checked you may choose one of
the available bitmap files from the adjacent combo box. See
“Configurable User Graphic” on page 18.
Report Style
When the number of columns is greater than 1 MStower will print multi- column reports, as long as there is room on the page. When there is insufficient room for the number of columns selected the number of columns is automatically reduced, as required. To increase the density of printing in a report you may increase the number of columns and reduce
the text size and margins.
Graphics Style
No color
With the exception of the configurable user graphic, which is always printed in its own colors, printing is in black only, even if using a color printer.
Heavy lines
Structure geometry is shown with heavy lines. This is more suitable for high-resolution printers, which otherwise print a very fine line.
Legends
Color legends for sections and load cases may be shown.
The section legend is only shown when section numbers are included on the plot. The load case legend is only shown for the load cases for which loads are plotted.
Scale
The scale at which structure geometry is shown. With a scale of 100, for example, 1 m on the structure is represented as 10 mm on the plot. When the scale is zero (default) the structure is plotted to fill the space available.
18• 2:GettingStarted MSTowerV6
Configurable User Graphic
You may use this feature to place your company logo at
the top of all printed output.
MStower allows you to have a small graphic at the top of each page of printed output. Any valid Windows bitmap file existing in the program folder may be selected in the Page Setup dialog box. With this option selected the graphic is printed on each page. If the option is not selected no graphic will be printed and no space will be allowed for it. On installation MStower is configured to use the graphic shown below. You can unselect the option in Page Setup if you do not want a graphic.
DEFAULT GRAPHIC
The specification of the bitmap is:
• Width – 1200 pixels
• Height – 200 pixels
• Colors – 256
Bitmaps that do not match these requirements are not shown in the Page Setup dialog box. MStower prints the graphic in a space 50.8 mm wide by 8.5 mm high.
Note: The Windows drivers for some printers do not support the printing of bitmaps.
Steel Section Libraries
A source file is supplied with each steel section library. The source file is a text file with the file name extension “asc” and the corresponding library file has a file name extension of “lib” (e.g. As.asc, As.lib).
Section Library Manager may be used to edit existing section libraries and create new ones.
TheFile > Configure > Section Library Manager command gives access to powerful facilities for editing an existing library or making a new library by merging sections from existing libraries – see “Chapter 13:Editing the Section Library” on page 229. When a library is saved it may be compiled into a library file accessible to MStower (see
“Compiling a Library” on page 236). It is recommended that you do not modify the standard libraries supplied with MStower – it is preferable to copy the source file to a file with a different name and then modify that.
Steel section libraries used with previous versions of MStower are compatible with those used by V6.
MSTowerV6 2:GettingStarted• 19
Data from Earlier Versions
All data files (TD, TWR, UDP) and section and ancillary libraries from previous versions and .mst files from V5 are compatible with MStower
V6.
To open a V3 or V4 job:
Select File > New then navigate to the data area and enter the job name.
SelectTower > Build Tower > Process Tower File. The job should now be displayed graphically.
To open a V5 job:
SelectFile > Open, and select the job. It should be displayed in the state in which it was last saved. Because the format of some work files has been changed to allow the addition of new capabilities, you must re- build the tower if you wish to do anything more than view the structure.
Technical Support
Click the Check Version button in the Help About MStower dialog box to
determine whether your software needs updating.
Microstran technical support is available by telephone, fax, and e-mail.
Use theHelp > About MStowercommand to display the serial number, the version number, and licence details for your software. This
information is required when you ask for technical support. The Help About dialog box contains links to the MStower website, where you may submit a support request or update your software.
HELP ABOUT MSTOWER
20• 2:GettingStarted MSTowerV6
Web Update
From time to time, minor updates are provided without charge on the MStower website. You may use the web update facility to determine when an update is required. While your computer is connected to the internet, clicking the Check Version button in the Help About dialog box displays the dialog box shown below. This shows the dates of your MStower software and dates of the current web downloads, making it very easy to see whether an update is required.
MSTOWER WEB UPDATE DIALOG BOX
You can connect to the MStower website by clicking the Downloads hot link in the Help About dialog box. Here, you will recognize the
components you need to download. Each download is an executable file – run it to unpack the update files. If prompted for a password when this
executable runs you must e-mail MStower Support to obtain it. A new CD may be purchased as an alternative to using the internet download facility.
When new versions (or majorupgrades) become available they are not available on the MStower website – they must be purchased on a CD.
MSTowerV6 3:Menus&Toolbars• 21
3:Menus & Toolbars
Layout
The diagram below shows the layout of the MStower screen. Commands may be initiated from the main menu, any toolbar, or a context (pop-up) menu. The main menu comprises amenu bar , each item of which gives access to adrop-down menu. Some items on drop-down menus lead to sub-menus. Each toolbar button usually corresponds to a command
accessible from the main menu. Context menus, which appear when you click the right mouse button, contain a selection of commands from the main menu. This chapter lists all the commands available on the main menu and all toolbars.
LAYOUT OF MSTOWER WINDOW
22• 3:Menus&Toolbars MSTowerV6
File Menu Commands
FILE MENU
The File menu offers the following commands:
Command Action
New Creates a new job.
Open Opens an existing job.
Close Closes the current job.
Save Saves the current job using the same file name.
Save As Saves the current job to a specified file name and changes the name of the current job accordingly.
Save Copy As Saves a copy of the current job to a specified file name.
Delete Deletes job files, optionally keeping source files.
List/Edit File Opens the selected file with the MsEdit text editor for viewing or editing.
Page Setup Change the printing options.
Print Preview Displays the selected file on the screen, as it would appear printed.
Print File Prints the selected file.
Import Reads data into MStower from a file (e.g. Microstran Archive file or CAD DXF). This command is only available when editing a UDP.
Export Writes MStower data to a file. File types include MStower archive file, results file, CAD DXF, and SDNF detailing file.
Configure Configuration of program capacity, section library, material library, colors, intermediate file folder, and timed backup interval. Also used for editing of section and material
MSTowerV6 3:Menus&Toolbars• 23 libraries and dynamic response spectra.
Recent Job Selects recently used job.
Exit Exits MStower
View Menu Commands
VIEW MENU
The View menu offers the following commands:
Command Action
Toolbars Shows or hides the toolbars.
Status Bar Shows or hides the status bar.
Redraw Redraws the current view.
Viewpoint Change the orientation of the structure in the view by selecting a new viewpoint.
Zoom Change the scale of the view or select a rectangular part of the view to fill the display window.
Pan Displace the view by the selected distance.
Limit Select a part of the structure by one of several available methods. Unselected parts are shown in light grey or hidden.
Full Redraws the current view so that it fills the window.
Copy Copy view to Windows clipboard in EMF format.
Print Preview Displays the view as it would appear printed Print View Prints the view.
Display Options Select options for displaying node numbers, member numbers, etc.
Ancillary Sort Order
Specify whether ancillaries will be sorted by serial number or height.
24• 3:Menus&Toolbars MSTowerV6 Virtual Reality Displays a rendered 3-D interactive view of the tower
model. You must have a VRML “plug-in” installed in your browser to use this facility.
Tower Menu Commands
TOWER MENU
The Tower menu offers the following commands:
Command Action
Build Tower Opens the tower data (TD) file for editing and processing. Includes graphical creation of user-defined panels.
Load Tower Opens the tower loading (TWR) file for editing and processing.
Analyse Analyses the tower.
Gust Factor Applies BS 8100 gust factoring to wind forces in tower members.
Build/Load/Analyse Runs all the previous items sequentially.
Member Checking Menu Commands
MEMBER CHECKING MENU
MSTowerV6 3:Menus&Toolbars• 25 The Member Checking menu offers the following commands:
Command Action
BS 8100 Part 3 Checks members to the rules of BS 8100 Part 3.
BS 449 Checks member to the rules of BS 449.
ASCE 10-90 Checks member to the rules of ASCE 10-90.
ASCE 10-97 Checks member to the rules of ASCE 10-97.
EIA-222-F Checks member to the rules of EIA-222-F.
TIA-222-G Checks member to the rules of TIA-222-G.
AS 3995 Checks member to the rules of AS 3995.
IS 802 Checks member to the rules of IS 802.
ILE Tech. Report 7 Checks poles to the rules of ILE Tech. Report.
ASCE Manual 72 Checks poles to the rules of ASCE Manual 72.
BS 5950 Checks poles to the rules of BS 5950.
AS 4100 Checks poles to the rules of AS 4100.
EIA-222-F Checks poles to the rules of EIA-222-F.
TIA-222-G Checks poles to the rules of TIA-222-G.
Structure Menu Commands
STRUCTURE MENU
The Structure menu becomes active only when graphically inputting a UDP. It offers the following commands:
Command Action
Draw Members Draw members or input node coordinates.
Erase Members Erase selected members.
Select All Selects all members, including any that may not be visible.
Drawing Settings Snap modes for drawing members, grid spacing etc.
26• 3:Menus&Toolbars MSTowerV6 Attributes Input attributes of the structure, such as restraints,
section numbers, etc.
Move Move a node, move members, rotate members, stretch nodes.
Copy Linear copy, polar copy, reflect members.
Sub-divide Sub-divide selected members into a number of equal parts.
Insert Node Insert a new node in a member.
Intersect Insert new node(s) at intersection of selected members.
Renumber Renumber nodes and members (sort or compact).
Analyse Menu Commands
ANALYSE MENU
The Analyse menu offers the following commands:
Command Action
Check Input Check structure and load data (normally automatic).
Linear Perform linear analysis (first-order).
Non-Linear Perform non-linear analysis (second-order).
Elastic Critical Load Determine frame buckling load factors and buckling mode shapes.
Dynamic Determine natural frequencies and mode shapes.
Response Spectrum Add response spectrum and static analysis results.
MSTowerV6 3:Menus&Toolbars• 27
Results Menu Commands
RESULTS MENU
The Results menu offers the following commands:
Command Action
Select Load Cases Select load cases for display of loads or results.
Select Natural Modes Select modes for display of vibration mode shapes.
Select Buckling Modes Select modes for display of buckling mode shapes.
Undisplaced Shape Display structure in undisplaced position.
Member Actions Display bending moment, shear force, axial force, torque, or displaced shape.
Natural Modes Display vibration mode shapes.
Animate Modes Show each currently displayed mode (natural or buckling) in alternate extreme positions. Press the
space bar to show the next mode, Esc to cancel.
Buckling Modes Display buckling mode shapes.
Design Ratios Display results of member design check with colors representing range of design ratios. The legend in the Output window shows the range of values represented by each color.
Reports Menu Commands
REPORTS MENU
The Reports menu offers the following commands:
Command Action
Input/Analysis Create report on structure and current analysis results.
28• 3:Menus&Toolbars MSTowerV6
Show Menu Commands
SHOW MENU
The Show menu offers the following commands:
Command Action
Section Highlight members with specified section number.
Material Highlight members with specified material number.
Member Type Highlight members of specified type (tension-only etc.).
Member Class Highlight members of specified classes such as legs, braces, etc.
Members Highlight specified members.
Panels Highlight members in a panel.
Wind Panels Highlight members to show how tower is sub-divided for wind load calculations.
Nodes Highlight members connected to specified nodes.
Master Nodes Show master nodes.
Slave Nodes Show slave nodes.
Node Masses Show all nodes with non-zero added mass.
Design Members Show all defined design members.
Cancel Cancel current “Show” selection.
MSTowerV6 3:Menus&Toolbars• 29
Query Menu Commands
QUERY MENU
The Query menu offers the following commands:
Command Action
Node Data List data for selected node (coordinates etc.).
Node Displacements List displacements for selected node.
Support Reactions List reactions for selected (support) node.
Master Node List slave nodes for selected master node.
Slave Node List constraints for selected slave node.
Member Data List member data for selected member.
Member Displacements List displacements for selected member.
Member Forces List member forces for selected member.
Node Loads List loads for selected node.
Member Loads List loads for selected member.
Design Member Highlight design member containing selected member.
Linear Ancillary List properties of linear ancillary.
Large Ancillary List properties of large ancillary.
Ancillary Group List properties of ancillary group.
Note: Query data is displayed in the Output window.
30• 3:Menus&Toolbars MSTowerV6
Window Menu Commands
WINDOW MENU
The Window menu offers the following commands, which enable you to arrange multiple views in the application window:
Command Action
Cascade Arranges windows in an overlapped fashion.
Tile Horizontally Arranges windows side-by-side.
Tile Vertically Arranges windows above and below.
Output Window Show or hide the Output window.
Window All open windows are listed. Clicking one of these will move the focus to the selected window.
MSTowerV6 3:Menus&Toolbars• 31
Help Menu Commands
HELP MENU
The Help menu offers the following commands:
Command Action
MStower Help Topics Display the Help Topics dialog box. This has three tabs, Contents, Index, and Find, so you can easily find help topics.
What’s This? Display help for clicked buttons, menus, and windows.
Tip of the Day Show Tip of the Day.
About MStower Display details about this copy of MStower and system resources. Also contains links to Internet.
Main Toolbar Commands
MAIN TOOLBAR
The Main toolbar offers the following commands:
• Open a new job.
• Open an existing job. MStower displays the Open dialog box, in which you can locate and open the desired file. This command is for opening an existing job – one for which there is already a Job.mst file, where “Job” is the name of the job as it was saved.
• Save the job with its current name.
• Print the view; i.e. print a picture showing the current view of the structure. Use theFile > Print command to print a file.
• Print preview; i.e. display exactly how the graphics will be printed.
Use theFile > Previewcommand to preview a file.
32• 3:Menus&Toolbars MSTowerV6
View Toolbar Commands
VIEW TOOLBAR
The View toolbar offers the following commands:
• Display front view.
• Display right view.
• Display top view.
• Display oblique view.
• Move viewpoint to left.
• Move viewpoint to right.
• Move viewpoint up.
• Move viewpoint down.
• Zoom to extents/limits of structure. If theView > Limit command is in effect, clicking this button alternately displays the full structure and the limited part of the structure.
• Zoom to selected window.
• Zoom in.
• Zoom out.
• Dynamically zoom view.
• Dynamically rotate view.
• Pan.
• Limit > Window command.
• Full View command.
• Show the Output window.
MSTowerV6 3:Menus&Toolbars• 33
Display Toolbar Commands
DISPLAY TOOLBAR
The Display toolbar offers the following commands:
• Display node symbols.
• Display of node numbers.
• Display member numbers.
• Display section numbers.
• Display supports.
• Display pins.
• Display rendered view of members.
• Display annotation of loads.
• Display annotation of member force or displacement diagrams.
• Increase scale for plotting loads, member forces, or displaced shape.
• Decrease scale for plotting loads, member forces, or displaced shape.
Help Toolbar Commands
HELP TOOLBAR
The Help toolbar offers the following commands:
• Help Topics. Starts HTML Help providing access to on-line help with display of User Manual contents, index, and search facility.
• Help About MStower. MStower version and licence details – includes links to internet.
34• 3:Menus&Toolbars MSTowerV6
Draw Toolbar Commands
DRAW TOOLBAR
The Draw toolbar is available during graphical input of UDPs only. It offers the following commands:
• Draw members.
• Erase members.
• Move members.
• Copy members.
• Reflect members.
• Sub-divide members.
• Rotate members.
• Display grid points and set Grid snap mode.
• Set Middle/End snap mode.
• Set Intersection snap mode.
Attributes Toolbar Commands
ATTRIBUTES TOOLBAR
The Attributes toolbar offers the following commands:
• Input section numbers.
• Input member releases.
• Input member orientation reference node/axis.
MSTowerV6 3:Menus&Toolbars• 35
Results Toolbar Commands
RESULTS TOOLBAR
The Results toolbar offers the following commands:
• Display undisplaced structure.
• Select load cases for display.
• Display applied loads.
• Display member actions. You must turn on this “switch” before you are able to select member forces for display.
• Display axial force, Fx.
• Display shear force, Fy.
• Display shear force, Fz.
• Display torque, Mx.
• Display bending moment, My.
• Display bending moment, Mz.
• Display displaced structure.
• Display natural vibration modes.
• Display buckling modes.
• Display design ratios. Design ratios are displayed graphically with different colors representing distinct ranges of values for the percentage of code capacity. For example, members shown bright
red are loaded in excess of 110% of the design code capacity.
• Display member force envelope.
• Animate modes (natural or buckling). Each mode is displayed in turn. Press the space bar to move to the next mode or Escape to exit mode animation.
OK/Cancel Toolbar Commands
OK/CANCEL TOOLBAR
The OK/Cancel toolbar is an alternative to the context menu for confirming or cancelling selections. Display or hide it with theView >
Toolbars command. This toolbar is not displayed initially.
36• 3:Menus&Toolbars MSTowerV6
Extra Buttons Toolbar Commands
EXTRA BUTTONS TOOLBAR
The Extra Buttons toolbar contains a number of buttons that may be added to other toolbars during customization. It is not displayed initially.
The buttons available are:
• Display back view.
• Display left view.
• Display y axis for all members.
• Polar copy.
• Intersect members.
• Insert node.
• Redraw (F5).
Selecting Which Toolbars Are Displayed
You may easily determine the toolbars that are displayed with theView
> Toolbars command. This displays the dialog box shown below. All checked toolbars are displayed.
TOOLBARS DIALOG BOX
Any toolbar that has been customized may be reset to the original configuration by selecting it and then clicking the Reset button.
MSTowerV6 3:Menus&Toolbars• 37
Customizing Toolbars
As well as being dockable, toolbars in MStower are customizable in two ways.
Firstly, while pressing the Alt key you may drag any button to any position on the same or another toolbar. If you drag a button to a new position not on a toolbar, it will disappear.
Secondly, you may click the Customize button in the Toolbars dialog box (View > Toolbars command). This displays the Customize property
sheet. Clicking the New button creates a new empty toolbar with any specified name. On the Commands tab you may now select any existing toolbar and drag its buttons onto the new toolbar (or any other toolbar).
CUSTOMIZING TOOLBARS
The Ouput Window
The Output window, normally at the bottom of the main window, is dockable. You may click on any part of the edge of the Output window and drag it, so that it floats inside the main window or docks on any edge of the main window. You may double-click on the title bar of the floating Output window and it will return to its previous docked position. Click the Output Window button to hide or display the Output window.
38• 3:Menus&Toolbars MSTowerV6
MSTowerV6 4:Operation• 39
4:Operation
Data Files
The tower is described in data files by the minimum number of key dimensions and a description of the types of panel in the tower. Panel types are described by mnemonics of one to four characters. Panels may be selected from a set of built-in face, plan, hip, and cross-arm patterns
or may be defined by the user.
The following data files are used:
• Job.td
Thetower data file.
• Job.udp
An optional file containing the description of non-standard or user- defined panels.
• Job.twr
Thetower loading file.
When a job is saved the above files and others associated with the job are copied into the job.mst file.
It may be convenient to copy the data files from an existing MStower job and edit these, rather than creating them from the beginning. This may be done by opening the existing job and selecting theFile > Save Copy
As command to create the new job.
The data files are text files, usually created and edited with the built-in text editor, MsEdit. Data is set out in blocks identified by keywords.
Blank lines may be used as required to improve the readability of the file. The “$” character may be used to introduce comments; the “$”
character and all text following on that line are ignored as input data.
Individual items of data may be separated by one or more blank spaces.
Each line of data must be no longer than 80 characters.
40• 4:Operation MSTowerV6 The following conventions are used to describe the input data:
Square brackets are used to indicate optional data items. A and B may be omitted in this example:
...[ A ] [ B ]...
Braces are used to indicate where a choice must be made from a list of items. Items may be shown vertically, or horizontally when separated by vertical bars. For example:
...{ item 1 }...
{ item 2 } { item 3 } or
...{ item 1 | item 2 | item3 }...
One of the items must be chosen.
An ellipsis, “…”, indicates that the data description in this manual is continued on the next line. Unless otherwise noted, the data in the file must be on one line.
Two dots, “..”, are used to indicate that there is a range of values between those shown, or that a series continues.
The “&” character at the end of a line indicates that the data continues on the next line.
Note: Square brackets, braces, the vertical line symbol, and the ellipsis are used to specify input – these characters do not appear in MStower data files.
Units
MStower accepts two sets of units:
• Metric – using meters, kilonewtons, tonnes, and degrees Celsius, with some data items being input and/or reported in the more customary units of mm and kg.
• US – using feet, kips, kip.sec2/ft, and degrees Fahrenheit, with some data items being input and/or reported in the more customary units of inches and pounds.
Entries in the ancillary and guy libraries are required in metric units.
Coordinate Systems
The vertical axis of the tower is parallel to the global Z axis. The X and Y axis of the tower lie in the horizontal plane and do not need to be aligned with the geographic north. The X axis is always normal (in plan) to one face of the tower.
Each member in MStower has its own set of member orlocal axes. The local x axis is aligned along the member while the local y and z axes correspond to the rectangular section axes. The reference node or axis defines the plane of the local y axis.
MSTowerV6 4:Operation• 41
Sections
All sections in the tower must be described in an MStower section library file. Dimensions and properties are automatically extracted to compute surface and projected areas when calculating ice and wind loads and for determining member capacities.
Member Checking
You must ensure that wind velocities and other factors used to compute loads are consistent with the code method chosen to check member strengths.
BS 8100 Part 3, AS 3995, ASCE10, TIA-222-G, and IS-802 are limit states codes, whereas EIA/TIA-222-F uses permissible stresses.
Export to Microstran Archive File
The MStower model may be exported to a Microstran archive file. This permits running of the model in the Microstran frame analysis and
design program.
Errors
After assembly of the tower, MStower checks for the following conditions:
Overlaid Members and Unconnected Nodes
These occur when a node is coincident with a member but not connected to it. When this occurs it is usually at the junction between panels and happens either because a horizontal has not been deleted or because of an incompatibility between panels. For example if a PL1 plan brace is used with an X face brace the PB1 member will overlay the H1 member.
The duplicated member will not be detected by the assembly process because of the mid-side node in PB1. A list of such members will be
displayed.
Floating Members
These are members that are not connected to the structure. If not removed they will result in errors during analysis. They can result if members are deleted; for example if PL1 plan bracing is used with XO face bracing and the PB1 member is deleted, the internal plan bracing members will not be connected to the tower. A list of such members will be displayed.
You may readily locate overlaid and floating members using MStower screen plots. Select theShow > Members command and then enter the list of offending members. The full tower will now be displayed with the listed members highlighted. You may zoom to inspect the members more closely and determine the reason for the error. The TD or UDP file should be modified as necessary.
