Page Comparison

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      Normal wt. concrete, minimum reinforcement                      0.37Öf’_c 37(f’_c)^1/2 (5^th Edition)

      Normal wt. concrete, minimum reinforcement                      0.24Öf’_c24(f’_c)^1/2

      Sand-lightweight concrete                                                     0.20Öf’_c20(f’_c)^1/2

      All-lightweight concrete                                                         0.17Öf’_c17(f’_c)^1/2

      All concrete types                                                                   0.24Öf’_c 24(f’_c)^1/2 (7^th Edition)

      Normal-density concrete                                                        0.40Öf’_c 40(f’_c)^1/2 (CHBDC)

      Semi-low-density concrete                                                     0.34Öf’_c 34(f’_c)^1/2 (CHBDC)

      Low-density concrete                                                              0.30Öf’_c 30(f’_c)^1/2 (CHBDC)

For normal weight concrete, the resistance factor for shear, f_v, is 0.90. For both types of lightweight concrete f_v is set to 0.70, but has been increased to 0.80 in the 6^th Edition, and to 0.90 in the 7^th Edition.  For CHBDC, f_s (steel) is 0.90, and f_c (concrete) is 0.80.

In accordance with LRFD Article 5.8.2.2/5.4.2.8, if lightweight concrete is specified, all occurrences of the term “Öf’_c“(f’_c)^1/2” within LRFD Articles 5.8.2/5.7.2 and 5.8.3/5.7.3 are modified by the following factors:

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