338 



FORM WORK 



: " 



FIG. 11 



concrete floor system that is particularly well constructed. 

 It may be readily set up and taken apart. The sheathing 

 ^g ,,. of the beam and girder forms 



and the plank used for the slab 

 centering are 2 in. in thickness. 

 The forms are supported by 

 4" X 4" studs. 



Wall Forms With Wire Ties. 

 A type of wall-form con- 

 struction that is frequently 

 used is illustrated in Fig. 8. In 

 order to prevent the sides of the 

 forms from spreading when 

 the concrete is tamped in place, 

 a wire tie c is used. This 

 tie is made taut by twisting 

 with a bar, or stick, d. To keep the form boards the proper 

 distance apart for the thickness of the wall, a block or stick 

 e of wood is sometimes inserted. 



Wall-Form Construction With Clamp Bolts. A wall-form 

 construction similar to that shown in Fig. 8 is illustrated in 

 Fig. 9. In this form, however, a clamp bolt a, instead of 

 a wire tie, is used to prevent spreading. If a bolt of this 

 character is used, it must be knocked out before the concrete 

 has finally set and when the form boards are to be raised to 

 form the next course of concrete. The bolt is preferable to 

 the wire tie, because it is removed from the concrete. Wire 

 ties are usually cut off close to the concrete work after the 

 form boards have been re- 

 moved, and as the ends fre- 

 quently project, they rust and 

 thus stain the wall. 



In Fig. 10 is shown the 

 construction of a wall form 

 in which a pipe separator a 

 is used with the clamp bolt. 

 The pipes may be driven out 

 of the concrete after it has obtained its initial set, or they 

 may be left in place. 



FIG. 12 



