Rectangular section shuttering tunnel - has frame formed of standard rails and brackets

摘要

The brackets (1a, 1b) made of metal tubing with square or rectangular cross-section have uprights (2a, 2b), horizontal arms (3a, 3b) and struts (4a, 4b). A slide-piece (5), of square or rectangular metal tubing, is placed in the two facing horizontal arms of two brackets. The brackets are joined by rails (6a, 6b) fixed by means of U-bolts (7c, 7d) onto the horizontal arms (3a, 3b). Wooden or metal vertical guide-pieces (8a, 8b) are fixed by means of U-bolts (9a, 9b) onto the rails (6a, 6b). Plywood panels (10a, 10b) are nailed or screwed onto the vertical guide-pieces (8a, 8b). Two sets of wooden or metal horizontal guide-pieces (11a, 11b) are fixed by means of U-bolts (19a, 19b) onto the rails (6c, 6d). Plywood panels (12a, 12b) are screwed or nailed onto each set of horizontal guide-pieces (11a, 11b).