D8.B.13 Column With Lacings And Battens

For columns with large loads it is desirable to build rolled sections at a distance and inter-connect them. The joining of element sections is done by two ways:

Lacing
Batten

Double channel sections (back-to-back and face-to-face) can be joined either by lacing or by batten plates having riveted or welded connection.

The following table gives the parameters that are required for Lacing or batten design. These parameters will have to be provided in unit NEW MMS along with parameters defined in D8.B.4 Design Parameters.

Note: Once a parameter is specified, its value stays at that specified number until it is specified again. This is the way STAAD.Pro works for all codes.

Table 1. Parameters used in Indian Lacing or Batten steel member design.
Parameter Name	Default Value	Description
CTYPE	1	Type of joining 1) implies single lacing with riveted connection 2) implies double lacing with riveted connection 3) implies single lacing with welded connection 4) implies double lacing with welded connection 5) implies batten with riveted connection 6) implies batten with welded connection
COG	0.0 mm	Center of gravity of the channel. This parameter is used when member properties are defined through user provided table using GENERAL option.
DBL	20 mm	Nominal diameter of rivet
DCFR	0.0	Used when member properties are defined through user provided table using GENERAL option. 0) double channel back-to-back. 1) double channel face-to-face.
EDIST	32 mm (riveted connection) 25 mm (welded connection)	Edge Distance.
FVB	100 N/mm²	Allowable shear stress in rivet
FYB	300 N/mm²	Allowable bearing stress in rivet
SPA	0.0 mm	Spacing between double channels. This parameter is used when member properties are defined through user provided table using GENERAL option.
THETA	50 degree	Angle of inclination of lacing bars. It should lie between 40 degree and 70 degree.
WMIN	6 mm	Minimum thickness of weld
WSTR	108 N/mm²	Allowable welding stress