Formwork for Concrete Structures by R.L.Peurifoy and G.D- By EasyEngineering.net

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Shores and Scaffolding 171
FIGURE 6-5 Spacing of shores for concrete beam (refer to section A−A in Figure 6-4).
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stem will be 18 in. deep and 15 in. wide. Thus, the total depth of the
beam is 23 in., 18-in. stem, plus the 5-in. slab. The concrete beam is 18 ft
0 in. long, which is the clear span between columns (see Figure 6-5).
The clear height from the lower floor to the bottom of the slab will be
10 ft 6 in.
In addition to the weight of the concrete, assume a temporary
construction live load of 50 lb per sq ft. Because the shoring for the
slab will be placed 2.5 ft, or 30 in., from the centerline of the shoring
for the beam, the load on the beam shoring must sustain the live load
acting over this distance along the beam form (Figure 6-5).
Consider the 23-in.-deep by 15-in.-wide beam and that portion of
the 5-in. slab adjacent to the shores that support the slab. The weight,
including the live load that will be applied to the beam shores can be
calculated:
Beam weight = [23 in. × 15 in.]/144 × (150 lb per cu ft)
= 360 lb per lin ft
Slab weight = 5 in. × [30 in. − 15 in.]/144 × (150 lb per cu ft)
= 78 lb per lin ft
Assume dead load of formwork = 8 lb sq ft × 2.5 ft = 20 lb per lin ft
Live load = 50 lb per sq ft × 2.5 f = 125 lb per lin ft
Total load = 583 lb per lin ft
Total load from beam = 583 lb per lin ft × 18 ft
= 10,494 lb
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