Original
General Order
95
Section
IV
Strength Requirements for All Classes of
Lines
48.3 Reinforced Concrete
Values used for ultimate strengths of reinforced concrete, in conjunction with safety factors given in Rule 44, shall not exceed the following:
Reinforcing steel, tensile or compressive strength, pounds per square inch - 55,000
Concrete, 1:2:4 mixture |
Age |
Compressive Strength |
|
|
7 days |
900 lbs per sq in. |
|
|
30 days |
2,400 lbs per sq in. |
|
|
90 days |
3,100 lbs per sq in. |
|
|
6 mos |
4,400 lbs per sq in. |
If reinforced concrete is designed for higher strength values which are proven by test, such values may be used in lieu of the figures given.