1964_BUILDING_(CONSTRUCTION)_REGULATIONS — Page 73

1985 Ed.]

Building (Construction; Regulations

[CAP. 123

B 73

(2) In a slender beam to which regulation 116(2) applies, the stress in any compression steel shall not exceed the permissible stress specified in Table XXIX for compression in main reinforcement multiplied by the appropriate coefficient specified in Table XXVIII.

(3) For the purpose of this regulation the modular ratio shall be taken as 15.

118. (1) Where a reinforced concrete column has a ratio of effective column length to least lateral dimension not exceeding 15. the stresses in that column shall not exceed the maximum permis- sible stresses specified in regulations 116 and 117.

(2) Where a reinforced concrete column has a ratio of effective length to least lateral dimension exceeding 15 and not exceeding 36, the stresses in that column shall not exceed the maximum permis- sible stress specified in regulations 116 and 117 multiplied by the coefficient specified in Table XXX for the appropriate ratio.

(3) The stress in a column due to a combination of direct load and bending action shall not exceed the maximum permissible stress for bending specified in regulations 116 and 117 multiplied by the coefficient specified in Table XXX for the appropriate ratio of length to least lateral dimension:

Provided that the direct/stress shall not exceed the stress specified in paragraph (2).

TABLE XXX

Stress reduction coefficients for slender columns

[Subsidiary]

Stresses in reinforced

concrete columns.

2

Ratio of effective column length

Coefficient

to least lateral dimension

IS

LO

18

9

21

.8

1.

24

.7

27

.6

30

.5

33

36

.4

.3

Note: The coefficient for intermediate ratios of effective column length to least

lateral dimension shall be determined by interpolation.

(4) The ratio of effective column length to least lateral dimen- sion for any reinforced concrete column or strut shall not exceed 36.