92 feet span. Length, 153 feet. Five main trusses, 25 feet apart. Height to eaves, 24 feet. Height to ridge, 50 feet.

Fig. 223.   Elevation.

Fig. 223. - Elevation.

Fig. 224.   Plan.

Fig. 224. - Plan.

Quantities.

Lbs.

3 trusses, at 17,860 ..............................

53,580

2 trusses, at 19,700 .................................

39,400

6 cast shoes...................

2,100

4 cast shoes........................

1,400

3 tie rods...........

2,457

2 tie rods.....................

1,980

28 purlins....................

19,100

8 "

9,600

18 " ........................................

22,400

8 " ...........................................

. 5,184

4 " .............

2 876

44 struts in bracing..............

4,488

36 struts in bracing..................

. 3,300

72 rods .........................

3,540

Total..........................

.171,400

Fig. 226.   Plan of Roof Framing.

Fig. 226. - Plan of Roof Framing.

This weight corresponds to 9.7 lbs. per square foot of sloping roof surface, or 11.7 lbs. per square foot of ground covered. -

The trusses in this case were built strong enough to carry a 13-foot gallery, on two sides and one end, to be added in future.

PHOENIX HALL, at Brockton, Mass., is 100 feet wide, and 144 long, outside. It has 5 main arches, 94 feet, c. to c. Distance between trusses is 24 feet. It is 33 feet high to eaves, and 67 feet to ridge. It has a gallery 17 feet wide. The only steel included for the gallery is the ten gallery brackets.

Quantities.

Lbs.

42 purlins.............

28,700

48 struts.............

6,600

Rod bracing.........

2,600

5 tie rods................

4,680

5 arches...............

99,500

10 shoes..................

3,100

10 gallery brackets...........

6,060

Total...........................

151,240

This weight is equal to 8.6 lbs. per square foot of sloping roof surface, or 10.6 lbs. per square foot of ground covered.

NORTHAMPTON ARMORY is 100 feet square. It has 3 main trusses, and 11 lines of trussed purlins. It has no gallery.

Quantities are as follows:

Lbs.

3 trusses, at 17,000..............

51,000

6 cast shoes, at 350.............

2,100

3 tie rods, at 780................

2,340

44 purlins, at 670....................

29,500

Struts in bottom chord................

5,200

Ties in bottom chord..................

2,100

Total........................

92,240

The sloping roof area = 11,600 sq. ft. . . Weight per sq. ft. = 92,240 11,600 = 7.95 lbs.

THE PALACE AMUSEMENT CO.'S RINK, at Hartford, Conn., is 104 feet wide and 124 feet long. It has 4 main ribs 54 feet high, c. to c, pins. It is 24 feet high to eaves. It has a gallery 16 feet above the floor. There are 7 lines of trussed purlins. The gallery in this case is framed of steel, the main brackets being included with the trusses.

Quantities.

Lbs.

Trusses and rafters.....................

132,400

Purlins.....................

34,400

Rods...........................

18,000

Total.........................................

184,800

Gallery.........................

67,600

Fig. 227.   Section, 13th Regiment Armory, Scranton, Pa.

Fig. 227. - Section, 13th Regiment Armory, Scranton, Pa.

The total exposed roof area is 15,600 square feet. Hence the weight per square foot is:

Roof..........................

184,800

15,600

=

11.8 lbs.

Gallery........................

67,000

15,600

=

4.4 lbs.

PROVIDENCE EXPOSITION HALL. - This is 118 feet wide, and 196 feet long. It has 7 main trusses, 20 feet high to eaves. Figure 103 illustrates the design.

Quantities.

Lbs.

7 trusses at 25 000 ..........

175,000

104 purlins, at 580...............................

60,300

7 tie rods, at 1,100

7,700

Rod bracing on rafters..................

4,000

96 spacing struts, at 100.........................

9,000

14 cast shoes, at 600.....................

8,400

Total...........................................

265,000

This weight corresponds with 9.5 lbs. per square foot sloping, or 11.5 lbs. per square foot horizontal.

The following illustrations and descriptions give a good idea of the manner in which some of the largest armories and coliseums have been roofed: