open timbering
open timbering
[′ō·pən ′tim·bə·riŋ] (mining engineering)
A method of supporting the ground in a mine shaft or tunnel; supports are several feet apart, with the ground between them secured by struts.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
open sheeting, open sheathing, open timbering

open sheeting
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.