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

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Pressure of Concrete on Formwork 29
Rate of
Filling
Forms
ft per hr
Lateral Pressure, lb per sq ft for the Temperature Indicated
40çF 50çF 60çF 70çF 80çF 90çF 100çF
1 600 600 600 600 600 600 600
2 600 600 600 600 600 600 600
3 825 690 600 600 600 600 600
4 1,050 870 750 664 600 600 600
5 1,275 1,050 900 793 713 650 600
6 1,500 1,230 1,050 921 825 750 690
7 1,725 1,410 1,200 1,050 938 850 780
8 1,795 1,466 1,247 1,090 973 882 808
9 1,865 1,522 1,293 1,130 1,008 913 836
10 1,935 1,578 1,340 1,170 1,043 944 864
11 2,005 1,634 1,387 1,210 1,078 975 892
P m
= C w
C c
[150
+ 9,000R/T ]
↑
↓
P m
= C w
C c
[150
+ 43,400/T
+ 2,800R/T ]
12 2,075 1,690 1,434 1,250 1,113 1,006 920
13 2,145 1,746 1,450 1,290 1,148 1,037 948
14 2,215 1,802 1,522 1,330 1,183 1,068 976
15 2,285 1,858 1,574 1,370 1,218 1,099 1004
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Notes:
1. Do not use design pressure greater than wh.
2. Concrete placement with normal internal vibration to a depth of 4 ft or less.
3. Values are based on concrete with C w
= 1 and C c
= 1.
4. Concrete without additives with a maximum slump of 7 in.
5. Minimum pressure is 600C w
lb per sq ft, but in no case greater than wh.
6. For pour rates greater than 15 ft per hr, use pressure P m
= wh.
7. Reference ACI Committee 347 for additional information on concrete form pressures [1].
TABLE 3-3 Relation between Rate of Filling Wall Forms, Lateral Pressure, and
Temperature for Placement Heights Up to 14 Feet
pressure will not exceed the pressure of wh = 150(6) = 900 lb per sq ft.
It should be noted that the left-hand column in Table 3-3 is the rate of
filling wall forms and not the height of wall.
Table 3-4 gives the relationship between the rate of filling wall
forms, lateral pressure, and temperature for placement heights greater
than 14 ft. The pressures are based on 150 lb per cu ft density concrete
with no additives, a maximum slump of 7 in., and vibration to a depth
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