The Arsenal Files 8/The Arsenal Files Collection #8 (Arsenal Computer) (1996).ISO/sci_calc/sb2us208.zip/REVIEW.TXT

Text File | 1996-09-20 | 8KB | 147 lines

                 SuperBeam 2 USA Lite shareware version 2.08

         Some notes for shareware vendors and non-technical reviewers
         ------------------------------------------------------------
Thank you for looking at SuperBeam 2. Like many vertical market applications
it is difficult for anyone who will not be using it in their business to
assess it properly but we hope that these notes will help. If some of the
explanatory text below is too simple please do not be offended.  If you do
understand these things please accept that we have tried to make the
explanations as simple as possible, thus the less than rigorous definitions.

The files that make up the package are supplied in the self-extracting
archive INSTALL.EXE which has been assembled using LHA. When run this
extracts most of the program files to \SDA and forms subdirectories
\SDA\SB2USPRJ and \SDA\TEXT below it.

SuperBeam 2 is a DOS application written using the Borland Pascal Turbo
Vision application framework so it works in a very similar way to most
Windows applications (it can be run as a DOS application under OS/2 or
Windows). A mouse is stromgly recommended, and a coprocessor will speed up
calculations significantly. The number displayed at the bottom right of the
screen is the amount of free memory available to the program - we recommend
a minimum of 500K free memory.

What does SuperBeam 2 do
------------------------
SuperBeam 2 is aimed at architects and engineers who design or check houses
and small commercial buildings. Most such buildings will incorporate one or
more beams, (lintels and floor joists are technically beams). Many of these
are designed using rules of thumb or standard tables but in many cases
calculations are needed to satisfy the building code inspectors (and others)
that the proposed size of beam will safely carry the loads on it.

SuperBeam was first released in the UK in 1989 and there are nearly one
thousand registered copies in use: the majority of UK building control
(building code enforcement) departments have one or more copies. The USA
version was first released in December 1994 and is specifically tailored for
American users (apart from anything else the majority of American design is
carried out in imperial units, whilst metric units are used in the UK and
Canada).

Beam design for non engineers
-----------------------------
SuperBeam 2 considers simply supported beams carrying uniformly distributed
loads (UDL's) and point loads (PL's). A simply supported beam is a beam that
rests on two supports - imagine a plank resting on two bricks. A line of
bricks laid out along the plank would act as a UDL, someone standing in the
middle would be called a PL. SuperBeam 2 lets you enter up to 15 loads per
beam - a beam in a house may be holding up a wall, a floor and a roof, and
these loads may need to be subdivided.

Beams can fail in one of three ways so we need to check that the proposed
section is satisfactory in all three respects. If it is not SuperBeam 2
displays a warning message.

If our plank was short (say 2' span = distance between the bricks supporting
it) and the load on it was progressively increased it would ultimately fail
in shear: the forces within it would be so great that the wood sheared along
the line of the grain. To make sure this does not happen we need to make sure
that the shear force generated by the load is less than what is permissible.

If the plank was of medium length (say 6' span) then it would probably fail
in bending before it failed in shear: either the wood on the top edge which
is in compression would start to crush or the wood on the bottom would start
to separate under the tensile forces resulting from the bending. To make sure
this does not happen we need to make sure that the bending stress generated
by the load is less than what is permissible.

If you had a very long plank then the acceptable load would be limited by the
deflection. Deflection (the amount by which a beam moves under the imposed
loads) is particularly important for beams supporting brickwork (as it would
crack if the beam deflected too much) and for beams that support floors: if a
floor moves up and down too much it tends to worry people, notwithstanding
the fact that the floor may be technically quite safe and nowhere near
collapsing.

The factors that govern the permissible stresses on steel and wood beams are
quite complicated: for wood beams the species and wood grade are important;
for steel beams the steel grade and shape of the member. Rules for designers
are set out in the two documents on which SuperBeam 2 USA is based: the
American Institute of Steel Construction (AISC) Manual of Steel Design, and
the American Forest & Paper Association National Design Specification (NDS)
for the Design of Wood Structures (the UK version of SuperBeam uses British
Standards which differ in many respects).

Usually the designer will want to choose the cheapest suitable section, but
sometimes other factors are more important: for example the depth of the
beam. The various options in the steel and wood beam design dialogs let users
select the important criteria.

OK - how do you use SuperBeam 2
-------------------------------
Enough of the crash course in structural engineering. Here's how you would
use SuperBeam 2 and produce the calculations for a steel beam spanning 15
feet carrying a UDL of 1000 lb/ft run:

1. Press [Alt-R] to activate the Project menu and select "New". Enter some
   details in the dialog that appears details, pressing [Tab] to move from
   one field to the next, and click on OK to confirm your entries.

2. Enter a filename under which your work is to be saved (or enter NUL to
   disable saving)

3. Press [Ctrl-S] to create a steel beam. The Load Entry dialog will appear.
   Enter a description for the beam (e.g. 'Test'), press [Tab], enter the
   span (15), press [Tab] again, press 'U' (for UDL), enter a description for
   this load (e.g. 'UDL'), press [Tab] again and enter the loading (1000). At
   this point you could enter additional loads, but for now press [Enter] to
   confirm the load entry.

4. A window appears showing the maximum bending moment, shear force and
   deflection.

5. Press [Alt-S] (or click on 'Steel' on the status line) to display the
   calculations for the lightest steel section capable of carrying the load,
   probably a W8 x 24. You can change the design parameters by pressing
   [Alt-D], check a particular section by choosing from the dialog that
   appears when you press [Alt-C], or you can move forward and backwards
   through the section table with [Ctrl-Left] and [Ctrl-Right]. These options
   are all shown on the status line.

6. If you are using an Epson compatible printer you can now press [Alt-P] to
   print out the calculation. If not press [Alt-V] to display the Print
   Preview window - this displays the calculation as it would be printed
   (press [Esc] or [F4] to close this window). If you are using any other
   sort of printer select the "Printer List" option from the Configuration
   menu and replace printer driver 1 (Default) with one appropriate to your
   printer.

7. Feel free to explore the other menu options. We would humbly suggest that
   we have the most useable calculator out - press [Alt-Equal] and see if you
   agree.

8. Press [Alt-X] to exit (or [Alt-R] to access the Project menu then exit.

Press [F1] (or the mouse right button) to access the context sensitive
on-line help.

If you have any queries please do not hesitate to contact us. We generally
check our CompuServe section (UKSHARE s.9 SDA/ZEPHYR) several times each day
so CompuServe users will probably find this the most cost effective way of
getting an answer.

                       Survey Design Associates Limited
            5A Waldegrave Gardens, Twickenham, Middx. TW1 4PQ  U.K.
               Tel: [phone]  Fax: [phone]