RAM Structural System Help

Steel Joist Tables — Standard Joists

For Standard joists, those loaded with a single uniform load, RAM Steel Beam Design is capable of selecting steel joists from joist load tables. Four joist tables are supplied with the Beam Design module. RAMSJIK.JST, RAMSJILH.JST, and RAMSJIDH.JST contain the Steel Joist Institute K-series, LH-series, and DLH-series respectively. The RAMSJI.JST file is a combination of the three previously mentioned files.

The tables are based on the load tables published by the Steel Joint Institute (S.J.I.). The members in these tables are ordered most economically by cost. Since this varies from manufacturer to manufacturer the user should review the joist table files and make adjustments as appropriate.

The tables may be in either English or SI units.

The tables must be in the Tables directory.

Steel joist tables can be created or modified by the user. Use spaces, not tabs, between items. The file must have the extension .JST.

CAUTION: Do not use a word processor as it might embed control characters into the file.

The file has the following format:

The character in the first line indicates the system of units used in the table: an E indicates English units and an S indicates SI units.

For each joist a section is created with the following format:

Label Depth W
Length1 TL1 LL1
Length2 TL2 LL2
Length3 TL3 LL3
…
Lengthn TLn LLn

where:

Label
is the name of the joist (13 characters or less),
Depth
is the depth (in. or mm),
W
is the weight per unit length (lb/ft or kg/m),
Lengthi
is the length for which the uniform load capacity is TLi and LLi (ft or m),
TLi
is the total uniform load capacity (lb/ft or kN/m),
LLi
is the uniform live load capacity which causes a deflection of L/360, not to exceed TLi (lb/ft or kN/m).

Joists are listed in order of ascending cost. For each joist, each line of Length, TL, and LL is listed in order of ascending length.

Each joist section is separated by a blank line.

The following is an example listing of a portion of a joist file.

E
10K1 10 5.0
10 550 550
11 550 542
.
.
.
20 199 97
12K1 12 5.0
12 550 550
13 550 510
.
.
.
24 166 81

If no member in the table is adequate for a given member, the last joist in the table will be selected whether it is adequate or not. It is necessary, therefore, that a "dummy" joist be included at the end of the table. The "dummy" joist label will serve as a flag that no sizes were found adequate for the conditions. The weight of the dummy joist should be 0.0 so that it is not included in the takeoff, and the depth of the member should be 0.0 so that it is not affected by depth restrictions.

An example of a "dummy" joist entry.

xxSJxx 0 0.0
9999 0 0

The file may contain 2000 different joist sizes and a maximum of 8100 joist entries.